Other Separations Techniques for Suspensions
PRESSURE-DRIVEN MEMBRANE SEPARATION
PROCESSES
1.1 INTRODUCTION
1.2 MEMBRANES
1.3 OPERATION
1.4 FACTORS AFFECTING PERFORMANCE
1.4.1 Polarization / Fouling
1.4.2 Pressure
1.4.3 Crossflow
1.4.4 Temperature
1.4.5 Concentration
1.4.6 Membrane Pore Size
1.4.7 Particle Size
1.4.8 Particle Charge
1.4.9 Other Factors
1.5 ADVANTAGES / LIMITATIONS
1.6 SUMMARY OF SYMBOLS USED
2 ELECTRO-DIALYSIS
2.1 INTRODUCTION
2.2 EQUIPMENT
2.3 IMPORTANT PARAMETERS IN ED
2.4 EXAMPLES
3 ELECTRODEWATERING AND ELECTRODECANTATION
3.1 INTRODUCTION
3.2 PRINCIPLES AND OPERATION
3.3 EQUIPMENT AND OPERATING PARAMETERS
3.4 EXAMPLES
4 MAGNETIC SEPARATION METHODS
5 REFERENCES
FIGURES
1 APPLICATION RANGES FOR MEMBRANE SEPARATION TECHNIQUES
2 SIMPLE UF / CMF RIG
4 FLUX VERSUS PRESSURE
5 ELECTRODIALYSIS PROCESS
6 ELECTRODIALYSIS PLANT FOR BATCH PROCESS
7 DEPENDENCE OF MEMBRANE AREA AND ENERGY ON
CURRENT DENSITY
8 DIFFUSION ACROSS THE BOUNDARY LAYER
Biological Systems: A Special Case
Up till now we have discussed various aspects of the separation and processing of fine solids without too much reference (except in the examples) to the specifics of the properties of the materials concerned. Though the material properties are the dominant influence on efficient process design and operation, it has been postulated that the necessary characteristics for process selection and optimization can be found fairly readily using easily-applicable rheological and other techniques. This underlying assumption also seems to hold good for biological suspensions; however, certain aspects of the behavior of these systems are sufficiently specialized for them to merit a separate discussion viz:
1 TYPES OF BIOLOGICAL SEPARATION
1.1 Whole-Organism Case
1.2 Part-Cell Separations
1.3 Isolation of Individual Molecular Species
2 SETTING ABOUT DEVISING AN EFFECTIVE
PROCESS FOR SEPARATION OF A BIOLOGICAL MATERIAL
2.1 Whole-Organism Case
2.1.1 Characterization of Biopolymers in the Liquor
2.1.2 Release of Internal Water
2.2 Part -Cell Separations
2.2.1 Selectivity
2.2.2 Cost
2.3 Isolation of Individual Molecular Species
3 Examples
3.1 Effective Design and Operation of a Process for Harvesting of Single Cell Protein
3.2 Harvesting of Mycoprotein for Human Consumption
3.3 Thickening of a Filamentous Organism Suspension
3.4 Separation of Poly-3-hydroxybutyrate Polymer (PHB) from Alcaligenes Eutrophus Biomass
3.5 Isolation of Organic Acid Produced by an Enzymatic Process
4 REFERENCES
Table
Figures
High Temperature Shift Catalyst Reduction ProcedureGerard B. Hawkins
High Temperature Shift Catalyst Reduction Procedure
The catalyst, as supplied, is Fe2O3. This reduces to the active form, Fe3O4, in the presence of hydrogen when process gas is admitted to the reactor.
1. The mildly exothermic reactions are:
3 Fe2O3 + H2 ========= 2 Fe3O4 + H2O
3 Fe2O3 + CO ========= 2 Fe3O4 + CO2
Catalytic Reforming technology - Infographics
IFP Fixed-bed Semi-regenerative Unit Revamps, Troubleshooting
IFP (CCR) Technology Optimization
In trying to determine the potential benefits from revamping a Fixed-bed Semi-Regenerative catalytic reformer, a refiner must evaluate several areas of operation:
— What is the unit operating objective?
— What degrees of freedom are available for revamp /optimization?
— Can refinery margins, and the discretionary capital budgeting program support the revamp / optimization?
Refiners must select the catalytic reformer operating point that will maximize profit within the following:
1) the mechanical constraints of the unit and
2) the short term unit operating objectives.
projects that improve operating profit are compared with the required capital investment.
This is done using discounted cash flow, or one of a number of other capital budgeting analysis tools, and those projects with the greatest return are put at the top of the capital budget list.
EMERGENCY ISOLATION OF CHEMICAL PLANTS
CONTENTS
1 Introduction
2 When should Emergency Isolation Valves be Installed
3 Emergency Isolation Valves and Associated Equipment
3.1 Installations on existing plant
3.2 Actuators
3.3 Power to close or power to open
3.4 The need for testing
3.5 Hand operated Emergency Valves
3.6 The need to stop pumps in an emergency
3.7 Location of Operating Buttons
3.8 Use of control valves for Isolation
4 Detection of Leaks and Fires
5 Precautions during Maintenance
6 Training Operators to use Emergency Isolation Valves
7 Emergency Isolation when no remotely operated valve is available
References
Glossary
Appendix I Some Fires or Serious Escapes of Flammable Gases or Liquids that could have been controlled by Emergency Isolation Valves
Appendix II Some typical Installations
The Selection of Flocculants and other Solid-Liquid Separation AidsGerard B. Hawkins
The use of chemical additives, such as flocculants, is a common step in solid-liquid separation operations. The correct selection of agent is an essential part of the design of such processes. Many excellent reviews and guides deal with this topic, and the interested reader is referred to works such as [l-4]. In particular the Harwell-Warren Spring Report “The Use and Selection of Flocculants" provides a good overview on the application of coagulants and flocculants. This section does not attempt to reproduce a detailed treatment of that kind; instead it is our intention to state a few general rules and principles concerning methods of choosing an additive, and to illustrate briefly their application in practice.
The types of agents employed in solid-liquid separation fall into three principal classes:
Low Temperature Shift Catalyst Reduction Procedure
VSG-C111 as supplied contains copper oxide; it is activated for the low temperature shift duty by reducing the copper oxide component to metallic copper with hydrogen. The reaction is highly exothermic. In order to achieve maximum activity, good performance and long life, it is essential that the reduction is conducted under correctly controlled conditions. Great care must be taken to avoid thermal damage during this critical operation.
Determination of Residue on Evaporation in Anhydrous AmmoniaGerard B. Hawkins
Determination of Residue on Evaporation in Anhydrous Ammonia
1 SCOPE AND FIELD OF APPLICATION
This method is suitable for the determination of the residue left after evaporation i.e., the non-volatile material in ammonia solution.
2 PRINCIPLE
A known weight of sample is evaporated to dryness in a platinum dish on a steam bath. The increase in mass of the dish is measured.
Biological Systems: A Special Case
Up till now we have discussed various aspects of the separation and processing of fine solids without too much reference (except in the examples) to the specifics of the properties of the materials concerned. Though the material properties are the dominant influence on efficient process design and operation, it has been postulated that the necessary characteristics for process selection and optimization can be found fairly readily using easily-applicable rheological and other techniques. This underlying assumption also seems to hold good for biological suspensions; however, certain aspects of the behavior of these systems are sufficiently specialized for them to merit a separate discussion viz:
1 TYPES OF BIOLOGICAL SEPARATION
1.1 Whole-Organism Case
1.2 Part-Cell Separations
1.3 Isolation of Individual Molecular Species
2 SETTING ABOUT DEVISING AN EFFECTIVE
PROCESS FOR SEPARATION OF A BIOLOGICAL MATERIAL
2.1 Whole-Organism Case
2.1.1 Characterization of Biopolymers in the Liquor
2.1.2 Release of Internal Water
2.2 Part -Cell Separations
2.2.1 Selectivity
2.2.2 Cost
2.3 Isolation of Individual Molecular Species
3 Examples
3.1 Effective Design and Operation of a Process for Harvesting of Single Cell Protein
3.2 Harvesting of Mycoprotein for Human Consumption
3.3 Thickening of a Filamentous Organism Suspension
3.4 Separation of Poly-3-hydroxybutyrate Polymer (PHB) from Alcaligenes Eutrophus Biomass
3.5 Isolation of Organic Acid Produced by an Enzymatic Process
4 REFERENCES
Table
Figures
High Temperature Shift Catalyst Reduction ProcedureGerard B. Hawkins
High Temperature Shift Catalyst Reduction Procedure
The catalyst, as supplied, is Fe2O3. This reduces to the active form, Fe3O4, in the presence of hydrogen when process gas is admitted to the reactor.
1. The mildly exothermic reactions are:
3 Fe2O3 + H2 ========= 2 Fe3O4 + H2O
3 Fe2O3 + CO ========= 2 Fe3O4 + CO2
Catalytic Reforming technology - Infographics
IFP Fixed-bed Semi-regenerative Unit Revamps, Troubleshooting
IFP (CCR) Technology Optimization
In trying to determine the potential benefits from revamping a Fixed-bed Semi-Regenerative catalytic reformer, a refiner must evaluate several areas of operation:
— What is the unit operating objective?
— What degrees of freedom are available for revamp /optimization?
— Can refinery margins, and the discretionary capital budgeting program support the revamp / optimization?
Refiners must select the catalytic reformer operating point that will maximize profit within the following:
1) the mechanical constraints of the unit and
2) the short term unit operating objectives.
projects that improve operating profit are compared with the required capital investment.
This is done using discounted cash flow, or one of a number of other capital budgeting analysis tools, and those projects with the greatest return are put at the top of the capital budget list.
EMERGENCY ISOLATION OF CHEMICAL PLANTS
CONTENTS
1 Introduction
2 When should Emergency Isolation Valves be Installed
3 Emergency Isolation Valves and Associated Equipment
3.1 Installations on existing plant
3.2 Actuators
3.3 Power to close or power to open
3.4 The need for testing
3.5 Hand operated Emergency Valves
3.6 The need to stop pumps in an emergency
3.7 Location of Operating Buttons
3.8 Use of control valves for Isolation
4 Detection of Leaks and Fires
5 Precautions during Maintenance
6 Training Operators to use Emergency Isolation Valves
7 Emergency Isolation when no remotely operated valve is available
References
Glossary
Appendix I Some Fires or Serious Escapes of Flammable Gases or Liquids that could have been controlled by Emergency Isolation Valves
Appendix II Some typical Installations
The Selection of Flocculants and other Solid-Liquid Separation AidsGerard B. Hawkins
The use of chemical additives, such as flocculants, is a common step in solid-liquid separation operations. The correct selection of agent is an essential part of the design of such processes. Many excellent reviews and guides deal with this topic, and the interested reader is referred to works such as [l-4]. In particular the Harwell-Warren Spring Report “The Use and Selection of Flocculants" provides a good overview on the application of coagulants and flocculants. This section does not attempt to reproduce a detailed treatment of that kind; instead it is our intention to state a few general rules and principles concerning methods of choosing an additive, and to illustrate briefly their application in practice.
The types of agents employed in solid-liquid separation fall into three principal classes:
Low Temperature Shift Catalyst Reduction Procedure
VSG-C111 as supplied contains copper oxide; it is activated for the low temperature shift duty by reducing the copper oxide component to metallic copper with hydrogen. The reaction is highly exothermic. In order to achieve maximum activity, good performance and long life, it is essential that the reduction is conducted under correctly controlled conditions. Great care must be taken to avoid thermal damage during this critical operation.
Determination of Residue on Evaporation in Anhydrous AmmoniaGerard B. Hawkins
Determination of Residue on Evaporation in Anhydrous Ammonia
1 SCOPE AND FIELD OF APPLICATION
This method is suitable for the determination of the residue left after evaporation i.e., the non-volatile material in ammonia solution.
2 PRINCIPLE
A known weight of sample is evaporated to dryness in a platinum dish on a steam bath. The increase in mass of the dish is measured.
GE / Texaco Gasifier Feed to a Lurgi Methanol Plant and its Effect on Methano...Gerard B. Hawkins
GE / Texaco Gasifier Feed to a Lurgi Methanol Plant and its Effect on Methanol Production
CONTENTS
0 Methanol Synthesis Introduction
1 Executive Summary
2 Design Basis
2.1.1 Train I Design Basis
2.1.2 Train II Design Basis
2.1.3 Train III Design Basis
2.2 Design Philosophy
2.2.1 Operability Review
2.3 Assumptions
2.4 Train IV Flowsheet
2.4.1 CO2 Removal
3 Discussion
3.1 Natural Gas Consumption Figures
3.1.1 Base Case
3.1.2 Case 1 – Coal Gasification in Service
3.1.3 Case 2 – Coal Gasification in Service – No CO2 Export
3.2 Methanol Production Figures
3.2.1 Base Case
3.2.2 Case 1 – Coal Gasification in Service
3.2.3 Case 2 – Coal Gasification in Service – No CO2 Export
3.3 85% Natural Gas Availability
3.4 100% Natural Gas Availability
3.5 CO2 Emissions
3.5.1 Base Case
3.5.2 Case 1 – Coal Gasification in Service
3.5.3 Case 2 – Coal Gasification in Service – No CO2 Export
3.6 Specific Consumption Figures
3.6.1 Base Case
3.6.2 Case 1 – Coal Gasification and CO2 Import
3.6.3 Case 2 – Coal Gasification and No CO2 Import
3.7 Train IV Synthesis Gas Composition
4 Further Work
5 Conclusion
APPENDIX
Important Stream Data – Material Balance Stream Data
Texaco Gasifier with HP Steam Raising Boiler
CHARACTERISTICS OF COAL
Material Balance Considerations
SYNGAS CONDITIONING UNIT FEASIBILITY CASE STUDY: COAL-TO-LIQUIDSGerard B. Hawkins
SYNGAS CONDITIONING UNIT FEASIBILITY CASE STUDY: COAL-TO-LIQUIDS
Case Study: #0953616GB/H
HT SHIFT REACTOR CATALYST SPECIFICATION
Process Specification
This process duty specification refers to a Syngas Conditioning Unit which utilizes HT Shift reaction technology on a slip stream of raw gas to produce a recombined gas stream with a H2:CO ratio of 1.57:1. This is an important consideration as the Shift reactor is not required to minimize CO at outlet, and this specification refers to the expected performance that can be achieved in a single stage reactor scheme.
The Syngas Conditioning Unit is part of a proposed coal-to-liquids complex in which synthesis gas is produced by gasification of coal for downstream processing in a Fischer Tropsch reactor and Hydrocracker unit.
BENFIELD LIQUOR:Determination of Diethanolamine Using an Auto TitratorGerard B. Hawkins
BENFIELD LIQUOR:Determination of Diethanolamine Using an Auto Titrator
1 SCOPE AND FIELD OF APPLICATION
This method is suitable for the determination of diethanolamine in Benfield Liquor.
2 PRINCIPLE
Diethanolamine is converted quantitatively into ammonia by boiling in the presence of sulfuric acid and copper sulfate. The ammonia is distilled from an alkaline medium and absorbed into boric acid. The solution is titrated with standard acid.
Procedure for Steam Reforming Catalyst Reduction with LPG Feed
Scope
This procedure may be used for the reduction of VULCAN Series Catalysts for the general steam reforming of LPG.
It is strongly advised that this procedure is adopted only where there is no other option available to use hydrogen, a hydrogen-rich gas or natural gas for the reduction stage. Reduction using the cracking of heavier hydrocarbons carries an extreme risk of catastrophic carbon formation in the event of any error in execution of the procedure.
Introduction
LPG is not normally utilized for steam reforming catalyst reduction although it can be used successfully. Caution is required if heavier hydrocarbons are used for catalyst reduction. Although operators have been able to reduce catalysts by using heavier hydrocarbon cracking, this has only been adopted where no other reductant option is available. The risk of carbon formation greatly increases as the carbon number of the feed increases when the catalyst is in the unreduced state. For the purposes of this procedure, LPG may range from a hydrocarbon mixture which is predominantly propane to one which is predominantly butane.
Calculation of an Ammonia Plant Energy Consumption: Gerard B. Hawkins
Calculation of an Ammonia Plant Energy Consumption:
Case Study: #06023300
Plant Note Book Series: PNBS-0602
CONTENTS
0 SCOPE
1 CALCULATION OF NATURAL GAS PROCESS FEED CONSUMPTION
2 CALCULATION OF NATURAL GAS PROCESS FUEL CONSUMPTION
3 CALCULATION OF NATURAL GAS CONSUMPTION FOR PILOT BURNERS OF FLARES
4 CALCULATION OF DEMIN. WATER FROM DEMIN. UNIT
5 CALCULATION OF DEMIN. WATER TO PACKAGE BOILERS
6 CALCULATION OF MP STEAM EXPORT
7 CALCULATION OF LP STEAM IMPORT
8 DETERMINATION OF ELECTRIC POWER CONSUMPTION
9 DETERMINATION OF THE TOTAL ENERGY CONSUMPTION OF THE AMMONIA PLANT ISBL
10 ADJUSTMENT OF ELECTRIC POWER CONSUMPTION FOR TEST RUN CONDITIONS
11 CALCULATION OF AMMONIA SHARE IN MP STEAM CONSUMPTION IN UTILITIES
12 CALCULATION OF AMMONIA SHARE IN ELECTRIC POWER CONSUMPTION IN UTILITIES
13 DETERMINATION OF THE TOTAL ENERGY CONSUMPTION OF THE AMMONIA PLANT OSBL
14 DETERMINATION OF THE TOTAL ENERGY CONSUMPTION OF THE AMMONIA PLANT
Study 2: Front-End Engineering Design and Project DefinitionGerard B. Hawkins
Study 2: Front-End Engineering Design and Project Definition
CONTENTS
2.0 PURPOSE
2.0.1 Team
2.0.2 Timing
2.0.3 Documentation
HAZARD STUDY 2: APPLICATION
2.1 Study of Process and Non-Process Activities
2.2 Study of Programmable Electronic Systems (PES)
2.3 Risk Assessment
2.4 Defining the Basis for Safe Operation
2.5 Review of Hazard Study 2
APPENDICES
Appendix A Hazard Study 2 Method
A.1 Significant Hazards Flowsheet
A.2 Event Guide Diagram
A.3 Consequence Guide Diagram
A.4 Typical Measures to Reduce Consequences
Appendix B Programmable Electronic Systems (PES) Guide Diagram
Appendix C Risk Assessment
C.1 Risk Assessment Procedure
C.2 Risk Matrix
C.3 Risk Matrix Guidance for Consequence Categories – Safety and Health Incidents
C.4 Risk Matrix Guidance for Consequence Categories – Environmental Incidents
Appendix D Key Hazards and Control Measures
Appendix E Content of Hazard Study 2 Report Package.
Determination of Oxygen in Anhydrous Ammonia
SCOPE AND FIELD OF APPLICATION
This method is suitable for the determination of trace amounts of oxygen in Liquefied anhydrous ammonia.
The trace oxygen analyzer provides for trace oxygen analysis in decade steps ranging from 0 - 10 to 0 - 10,000 ppm v/v (full scale).
The Design and Layout of Vertical Thermosyphon ReboilersGerard B. Hawkins
The Design and Layout of Vertical Thermosyphon Reboilers
0 INTRODUCTION/PURPOSE
1 SCOPE
2 FIELD OF APPLICATION
3 DEFINITIONS
4 THE DESIGN PROBLEM
5 COMPUTER PROGRAMS
6 GENERAL CONSIDERATIONS
6.1 Heating Medium Temperature
6.2 Fouling Resistance
7 DESIGN PARAMETERS
7.1 Overall Arrangement and Specifications
7.2 Geometry Elements
8 ANALYSIS OF COMMERCIALLY AVAILABLE
PROGRAM RESULTS
8.1 Main Results
8.2 Supplementary Results
8.3 Error Analysis
8.4 Adjustments to Design
9 OPERATING RANGE
10 CONTROL
10.1 Control of Condensing Heating Medium Pressure
10.2 Control of The Condensate Level
10.3 Control of Sensible Fluid Flow Rate
11 LAYOUT
11.1 Factors Influencing Design
11.2 A Standard Layout
12 BIBLIOGRAPHY
Determination of Inert Gas in Anhydrous Ammonia
ANHYDROUS AMMONIA: DETERMINATION OF INERT GASES
SCOPE AND FIELD OF APPLICATION
This packed-column GC method is suitable for the determination of hydrogen, nitrogen, oxygen, argon and carbon monoxide in anhydrous ammonia. The determinations of the gases are linear in the range O-100 ppm v/v.
Debottlenecking Claus Sulfur Recovery Units: An Investigation of the applicat...Gerard B. Hawkins
Debottlenecking Claus Sulfur Recovery Units: An Investigation of the application of Zinc Titanates
1 Executive Summary
2 Claus Process
2.1 Partial Combustion Claus
2.2 Split Flow Claus
2.3 Sulfur Recycle Claus
3 Zinc Titanates
4 Application of Zinc Titanate to Debottleneck Partial Combustion Claus by 10%
4.1 Process
4.2 ASPEN Modeling Results
4.3 Cost of Zinc Titanate Bed Installation
4.3.1 Basis of Costing
4.3.2 Zinc Titanate Beds
4.3.3 Regen Cooler
4.3.4 Blowers
4.3.5 Results
4.4 Alternative Debottlenecking Technology for Partial Combustion Claus
4.5 Cost of 10% Debottlenecking Using COPE Process
5 Debottlenecking Claus Split Flow System by 10% with Zinc Titanates
6 Debottlenecking Claus Sulfur Recycle System With Zinc Titanate
7 Effect of Zinc Titanate Debottlenecking on Existing Tail; Gas Treatment Systems
7.1 Selectox
7.2 SuperClaus99
7.3 Superclaus 99.5
7.4 SCOT Process
7.5 Zinc Titanate as a Claus Tail Gas Treatment
7.6 H2S Removal Efficiency With Zinc Titanate
8 Effects on COS and CS2 Formation
9 Questions for further Investigation
FIGURES
Figure 1 Claus Unit and TGCU
Figure 2 Claus Process
Figure 3 Typical Claus Sulfur Recovery Unit
Figure 4 Two-Stage Claus SRU
Figure 5 The Super Claus Process
Figure 6 SCOT
Figure 7 SCOT/BSR-MDEA (or clone) TGCU
REFERENCES: PATENTS
US4333855_PROMOTED_ZINC_TITANATE_CATALYTIC_AGENT
US4394297_ZINC_TITANATE_CATALYST
US6338794B1_DESULFURIZATION_ZINC_TITANATE_SORBENTS
DESIGN OF VENT GAS COLLECTION AND DESTRUCTION SYSTEMS Gerard B. Hawkins
DESIGN OF VENT GAS COLLECTION AND DESTRUCTION SYSTEMS
CONTENTS
1 INTRODUCTION
1.1 Purpose
1.2 Scope of this Guide
1.3 Use of the Guide
2 ENVIRONMENTAL ISSUES
2.1 Principal Concerns
2.2 Mechanisms for Ozone Formation
2.3 Photochemical Ozone Creation Potential
2.4 Health and Environmental Effects
2.5 Air Quality Standards for Ground Level Concentrations of Ozone, Targets for Reduction of VOC Discharges and Statutory Discharge Limits
3 VENTS REDUCTION PHILOSOPHY
3.1 Reduction at Source
3.2 End-of-pipe Treatment
4 METHODOLOGY FOR COLLECTION & ASSESSMENT OF PROCESS FLOW DATA
4.1 General
4.2 Identification of Vent Sources
4.3 Characterization of Vents
4.4 Quantification of Process Vent Flows
4.5 Component Flammability Data Collection
4.6 Identification of Operating Scenarios
4.7 Quantification of Flammability Characteristics for Combined Vents
4.8 Identification, Quantification and Assessment of Possibility of Air Ingress Routes
4.9 Tabulation of Data
4.10 Hazard Study and Risk Assessment
4.11 Note on Aqueous / Organic Wastes
4.12 Complexity of Systems
4.13 Summary
5 SAFE DESIGN OF VENT COLLECTION HEADER SYSTEMS
5.1 General
5.2 Process Design of Vent Headers
5.3 Liquid in Vent Headers
5.4 Materials of Construction
5.5 Static Electricity Hazard
5.6 Diversion Systems
5.7 Snuffing Systems
6 SAFE DESIGN OF THERMAL OXIDISERS
6.1 Introduction
6.2 Design Basis
6.3 Types of High Temperature Thermal Oxidizer
6.4 Refractories
6.5 Flue Gas Treatment
6.6 Control and Safety Systems
6.7 Project Program
6.8 Commissioning
6.9 Operational and Maintenance Management
APPENDICES
A GLOSSARY
B FLAMMABILITY
C EXAMPLE PROFORMA
D REFERENCES
DOCUMENTS REFERRED TO IN THIS PROCESS GUIDE
TABLE
1 PHOTOCHEMICAL OZONE CREATION POTENTIAL REFERENCED
TO ETHYLENE AS UNITY
FIGURES
1 SCHEMATIC OF TYPICAL VENT COLLECTION AND THERMAL OXIDIZER SYSTEM
2 TYPICAL KNOCK-OUT POT WITH LUTED DRAIN
3 SCHEMATIC OF DIVERSION SYSTEM
4 CONVENTIONAL VERTICAL THERMAL OXIDIZER
5 CONVENTIONAL OXIDIZER WITH INTEGRAL WATER SPARGER
6 THERMAL OXIDIZER WITH STAGED AIR INJECTION
7 DOWN-FIRED UNIT WITH WATER BATH QUENCH
8 FLAMELESS THERMAL OXIDATION UNIT
9 THERMAL OXIDIZER WITH REGENERATIVE HEAT RECOVERY
10 TYPICAL PROJECT PROGRAM
11 TYPICAL FLAMMABILITY DIAGRAM
12 EFFECT OF DILUTION WITH AIR
13 EFFECT OF DILUTION WITH AIR ON 100 Rm³ OF FLAMMABLE GAS
BENFIELD LIQUOR: DETERMINATION OF IRON
SCOPE AND FIELD OF APPLICATION
This method is suitable for the determination of the total iron in Benfield liquor samples up to a concentration of approximately 100 ppm m/v.
Determination of Residue and Oil in Anhydrous AmmoniaGerard B. Hawkins
Plant Analytical Techniques
Determination of Residue and Oil in Anhydrous Ammonia
This method is suitable for the determination of residue and oil in anhydrous ammonia.
FIELD OF APPLICATION
This method may be applied to standard and premium grade anhydrous ammonia having residue content in the range 10-5000 micrograms per gram and oil content in the range l-500 micrograms per gram
Operational Problems
Catalytic Reactor Process - Prompt List
- Feed Issues:
- Pipe work type Issues
- Operational Issues
- Vessel Loading
- Vessel Designs
- Wider Process Issues
- Material Issues
- Discharge issues
- Things to look at
- Things to consider trying
0 INTRODUCTION
The four main sources of Fugitive Emissions on most plants are valves, machine seals, re-makable joints and pressure relief devices. Other possible sources include open-ended lines, sampling connections, drains and vents.
Sometimes special precautions are taken to minimize Fugitive Emissions, for example the use of bellows seal valves. However, generally no special precautions are taken and the subsequent Fugitive Emissions to atmosphere represent a significant amount of plant losses.
Regulatory requirements covering Fugitive Emissions exist in many countries and therefore a leak reduction program should be implemented. Fugitive Emissions also represent financial losses to the business as well as potential damage to the environment.
"SEDIMENTATION"
INTRODUCTION - THE PHENOMENON OF SEDIMENTATION
Sedimentation is the physical process whereby solid particles, of greater density than their suspending medium, will tend to separate into regions of higher concentration under the influence of gravity. As a solids/liquids separation technique it therefore possesses the great advantage of utilizing a natural, and therefore costless, driving force. This section of the suspension processing Guide is Intended to provide an Introduction to the science of the subject, and the means to judge where and how best to exploit sedimentation as a separation (or other processing) technique.
As a scientific discipline the subject of sedimentation is vast with perspectives ranging from the field of chemical engineering through to theoretical physics being covered In the literature [1-11]. Good reviews of the subject, with a bias towards the engineering aspects, have been written by Fitch and Koz [12, 13]. A short summary of some of the more relevant contributions from the literature is also provided in GBHE-SPG-PEG-302 “Basic Principles & Test Methods”, of the Suspensions Processing Guides.
.
The sedimentation process is traditionally divided into ..."
Process Synthesis
INTRODUCTION
1 A SUGGESTED GENERAL APPROACH
2 EXAMPLES OF PROCESS SELECTION
2.1 Harvesting and Thickening of Single Cell Protein
2.2 Dewatering of a Specialty Latex
3 REFERENCES
TABLES
1 THE ADVANTAGES AND DISADVANTAGES OF DIFFERENT RANGE OF PH FOR “PROTEIN” ORGANISM FLOCCULATION
2 THE ADVANTAGES AND DISADVANTAGES OF VARYING EXTENTS OF CELL BREAKAGES
3 PREDICTED AND OBSERVED FILTER CAKE SOLIDS CONTENTS FOR THE VARIOUS LATICES AFTER COAGULATION
FIGURES
1 THE “PROTEIN” BACTERIAL HARVESTING SYSTEM
2 PROCESS FOR MANUFACTURE OF CALCIUM CARBONATE FILTERS
3 H-ACID ISOLATION
4 A SUGGESTED APPROACH TO DETERMINING FEASIBLE PROCESS OPTIONS, AND OPERATING CONDITIONS FOR SEPARATION OF FINE SOLIDS FROM SUSPENSION
5 MODULI VERSUS SOLIDS CONTENT FORTYPICAL FORWARD FLOCCULATED “PROTEIN” SUSPENSIONS
6 DECISION TREE FOR SELECTION OF AS1 HARVESTING CONDITIONS WHEN PRINCIPAL CONSTRAINT CONCERNS THE DEGREE OF THICKENING REQUIRED IN THE CONCENTRATE
7 DECISION TREE FOR SELECTION OF AS1 HARVESTING CONDITIONS WHEN PRINCIPAL CONSTRAINT CONCERNS THE USE OF FLOTATION AS A UNIT OPERATION FOR THICKENING
8 DECISION TREE FOR SELECTION OF AS1 HARVESTING CONDITIONS WHEN PRINCIPAL CONSTRAINT CONCERNS THE QUALITY OF THE RECYCLED LIQUOR
9 MODULUS SOLIDS CONTENT CURVES FOR THEVARIOUS COAGULATED LATICES
GE / Texaco Gasifier Feed to a Lurgi Methanol Plant and its Effect on Methano...Gerard B. Hawkins
GE / Texaco Gasifier Feed to a Lurgi Methanol Plant and its Effect on Methanol Production
CONTENTS
0 Methanol Synthesis Introduction
1 Executive Summary
2 Design Basis
2.1.1 Train I Design Basis
2.1.2 Train II Design Basis
2.1.3 Train III Design Basis
2.2 Design Philosophy
2.2.1 Operability Review
2.3 Assumptions
2.4 Train IV Flowsheet
2.4.1 CO2 Removal
3 Discussion
3.1 Natural Gas Consumption Figures
3.1.1 Base Case
3.1.2 Case 1 – Coal Gasification in Service
3.1.3 Case 2 – Coal Gasification in Service – No CO2 Export
3.2 Methanol Production Figures
3.2.1 Base Case
3.2.2 Case 1 – Coal Gasification in Service
3.2.3 Case 2 – Coal Gasification in Service – No CO2 Export
3.3 85% Natural Gas Availability
3.4 100% Natural Gas Availability
3.5 CO2 Emissions
3.5.1 Base Case
3.5.2 Case 1 – Coal Gasification in Service
3.5.3 Case 2 – Coal Gasification in Service – No CO2 Export
3.6 Specific Consumption Figures
3.6.1 Base Case
3.6.2 Case 1 – Coal Gasification and CO2 Import
3.6.3 Case 2 – Coal Gasification and No CO2 Import
3.7 Train IV Synthesis Gas Composition
4 Further Work
5 Conclusion
APPENDIX
Important Stream Data – Material Balance Stream Data
Texaco Gasifier with HP Steam Raising Boiler
CHARACTERISTICS OF COAL
Material Balance Considerations
SYNGAS CONDITIONING UNIT FEASIBILITY CASE STUDY: COAL-TO-LIQUIDSGerard B. Hawkins
SYNGAS CONDITIONING UNIT FEASIBILITY CASE STUDY: COAL-TO-LIQUIDS
Case Study: #0953616GB/H
HT SHIFT REACTOR CATALYST SPECIFICATION
Process Specification
This process duty specification refers to a Syngas Conditioning Unit which utilizes HT Shift reaction technology on a slip stream of raw gas to produce a recombined gas stream with a H2:CO ratio of 1.57:1. This is an important consideration as the Shift reactor is not required to minimize CO at outlet, and this specification refers to the expected performance that can be achieved in a single stage reactor scheme.
The Syngas Conditioning Unit is part of a proposed coal-to-liquids complex in which synthesis gas is produced by gasification of coal for downstream processing in a Fischer Tropsch reactor and Hydrocracker unit.
BENFIELD LIQUOR:Determination of Diethanolamine Using an Auto TitratorGerard B. Hawkins
BENFIELD LIQUOR:Determination of Diethanolamine Using an Auto Titrator
1 SCOPE AND FIELD OF APPLICATION
This method is suitable for the determination of diethanolamine in Benfield Liquor.
2 PRINCIPLE
Diethanolamine is converted quantitatively into ammonia by boiling in the presence of sulfuric acid and copper sulfate. The ammonia is distilled from an alkaline medium and absorbed into boric acid. The solution is titrated with standard acid.
Procedure for Steam Reforming Catalyst Reduction with LPG Feed
Scope
This procedure may be used for the reduction of VULCAN Series Catalysts for the general steam reforming of LPG.
It is strongly advised that this procedure is adopted only where there is no other option available to use hydrogen, a hydrogen-rich gas or natural gas for the reduction stage. Reduction using the cracking of heavier hydrocarbons carries an extreme risk of catastrophic carbon formation in the event of any error in execution of the procedure.
Introduction
LPG is not normally utilized for steam reforming catalyst reduction although it can be used successfully. Caution is required if heavier hydrocarbons are used for catalyst reduction. Although operators have been able to reduce catalysts by using heavier hydrocarbon cracking, this has only been adopted where no other reductant option is available. The risk of carbon formation greatly increases as the carbon number of the feed increases when the catalyst is in the unreduced state. For the purposes of this procedure, LPG may range from a hydrocarbon mixture which is predominantly propane to one which is predominantly butane.
Calculation of an Ammonia Plant Energy Consumption: Gerard B. Hawkins
Calculation of an Ammonia Plant Energy Consumption:
Case Study: #06023300
Plant Note Book Series: PNBS-0602
CONTENTS
0 SCOPE
1 CALCULATION OF NATURAL GAS PROCESS FEED CONSUMPTION
2 CALCULATION OF NATURAL GAS PROCESS FUEL CONSUMPTION
3 CALCULATION OF NATURAL GAS CONSUMPTION FOR PILOT BURNERS OF FLARES
4 CALCULATION OF DEMIN. WATER FROM DEMIN. UNIT
5 CALCULATION OF DEMIN. WATER TO PACKAGE BOILERS
6 CALCULATION OF MP STEAM EXPORT
7 CALCULATION OF LP STEAM IMPORT
8 DETERMINATION OF ELECTRIC POWER CONSUMPTION
9 DETERMINATION OF THE TOTAL ENERGY CONSUMPTION OF THE AMMONIA PLANT ISBL
10 ADJUSTMENT OF ELECTRIC POWER CONSUMPTION FOR TEST RUN CONDITIONS
11 CALCULATION OF AMMONIA SHARE IN MP STEAM CONSUMPTION IN UTILITIES
12 CALCULATION OF AMMONIA SHARE IN ELECTRIC POWER CONSUMPTION IN UTILITIES
13 DETERMINATION OF THE TOTAL ENERGY CONSUMPTION OF THE AMMONIA PLANT OSBL
14 DETERMINATION OF THE TOTAL ENERGY CONSUMPTION OF THE AMMONIA PLANT
Study 2: Front-End Engineering Design and Project DefinitionGerard B. Hawkins
Study 2: Front-End Engineering Design and Project Definition
CONTENTS
2.0 PURPOSE
2.0.1 Team
2.0.2 Timing
2.0.3 Documentation
HAZARD STUDY 2: APPLICATION
2.1 Study of Process and Non-Process Activities
2.2 Study of Programmable Electronic Systems (PES)
2.3 Risk Assessment
2.4 Defining the Basis for Safe Operation
2.5 Review of Hazard Study 2
APPENDICES
Appendix A Hazard Study 2 Method
A.1 Significant Hazards Flowsheet
A.2 Event Guide Diagram
A.3 Consequence Guide Diagram
A.4 Typical Measures to Reduce Consequences
Appendix B Programmable Electronic Systems (PES) Guide Diagram
Appendix C Risk Assessment
C.1 Risk Assessment Procedure
C.2 Risk Matrix
C.3 Risk Matrix Guidance for Consequence Categories – Safety and Health Incidents
C.4 Risk Matrix Guidance for Consequence Categories – Environmental Incidents
Appendix D Key Hazards and Control Measures
Appendix E Content of Hazard Study 2 Report Package.
Determination of Oxygen in Anhydrous Ammonia
SCOPE AND FIELD OF APPLICATION
This method is suitable for the determination of trace amounts of oxygen in Liquefied anhydrous ammonia.
The trace oxygen analyzer provides for trace oxygen analysis in decade steps ranging from 0 - 10 to 0 - 10,000 ppm v/v (full scale).
The Design and Layout of Vertical Thermosyphon ReboilersGerard B. Hawkins
The Design and Layout of Vertical Thermosyphon Reboilers
0 INTRODUCTION/PURPOSE
1 SCOPE
2 FIELD OF APPLICATION
3 DEFINITIONS
4 THE DESIGN PROBLEM
5 COMPUTER PROGRAMS
6 GENERAL CONSIDERATIONS
6.1 Heating Medium Temperature
6.2 Fouling Resistance
7 DESIGN PARAMETERS
7.1 Overall Arrangement and Specifications
7.2 Geometry Elements
8 ANALYSIS OF COMMERCIALLY AVAILABLE
PROGRAM RESULTS
8.1 Main Results
8.2 Supplementary Results
8.3 Error Analysis
8.4 Adjustments to Design
9 OPERATING RANGE
10 CONTROL
10.1 Control of Condensing Heating Medium Pressure
10.2 Control of The Condensate Level
10.3 Control of Sensible Fluid Flow Rate
11 LAYOUT
11.1 Factors Influencing Design
11.2 A Standard Layout
12 BIBLIOGRAPHY
Determination of Inert Gas in Anhydrous Ammonia
ANHYDROUS AMMONIA: DETERMINATION OF INERT GASES
SCOPE AND FIELD OF APPLICATION
This packed-column GC method is suitable for the determination of hydrogen, nitrogen, oxygen, argon and carbon monoxide in anhydrous ammonia. The determinations of the gases are linear in the range O-100 ppm v/v.
Debottlenecking Claus Sulfur Recovery Units: An Investigation of the applicat...Gerard B. Hawkins
Debottlenecking Claus Sulfur Recovery Units: An Investigation of the application of Zinc Titanates
1 Executive Summary
2 Claus Process
2.1 Partial Combustion Claus
2.2 Split Flow Claus
2.3 Sulfur Recycle Claus
3 Zinc Titanates
4 Application of Zinc Titanate to Debottleneck Partial Combustion Claus by 10%
4.1 Process
4.2 ASPEN Modeling Results
4.3 Cost of Zinc Titanate Bed Installation
4.3.1 Basis of Costing
4.3.2 Zinc Titanate Beds
4.3.3 Regen Cooler
4.3.4 Blowers
4.3.5 Results
4.4 Alternative Debottlenecking Technology for Partial Combustion Claus
4.5 Cost of 10% Debottlenecking Using COPE Process
5 Debottlenecking Claus Split Flow System by 10% with Zinc Titanates
6 Debottlenecking Claus Sulfur Recycle System With Zinc Titanate
7 Effect of Zinc Titanate Debottlenecking on Existing Tail; Gas Treatment Systems
7.1 Selectox
7.2 SuperClaus99
7.3 Superclaus 99.5
7.4 SCOT Process
7.5 Zinc Titanate as a Claus Tail Gas Treatment
7.6 H2S Removal Efficiency With Zinc Titanate
8 Effects on COS and CS2 Formation
9 Questions for further Investigation
FIGURES
Figure 1 Claus Unit and TGCU
Figure 2 Claus Process
Figure 3 Typical Claus Sulfur Recovery Unit
Figure 4 Two-Stage Claus SRU
Figure 5 The Super Claus Process
Figure 6 SCOT
Figure 7 SCOT/BSR-MDEA (or clone) TGCU
REFERENCES: PATENTS
US4333855_PROMOTED_ZINC_TITANATE_CATALYTIC_AGENT
US4394297_ZINC_TITANATE_CATALYST
US6338794B1_DESULFURIZATION_ZINC_TITANATE_SORBENTS
DESIGN OF VENT GAS COLLECTION AND DESTRUCTION SYSTEMS Gerard B. Hawkins
DESIGN OF VENT GAS COLLECTION AND DESTRUCTION SYSTEMS
CONTENTS
1 INTRODUCTION
1.1 Purpose
1.2 Scope of this Guide
1.3 Use of the Guide
2 ENVIRONMENTAL ISSUES
2.1 Principal Concerns
2.2 Mechanisms for Ozone Formation
2.3 Photochemical Ozone Creation Potential
2.4 Health and Environmental Effects
2.5 Air Quality Standards for Ground Level Concentrations of Ozone, Targets for Reduction of VOC Discharges and Statutory Discharge Limits
3 VENTS REDUCTION PHILOSOPHY
3.1 Reduction at Source
3.2 End-of-pipe Treatment
4 METHODOLOGY FOR COLLECTION & ASSESSMENT OF PROCESS FLOW DATA
4.1 General
4.2 Identification of Vent Sources
4.3 Characterization of Vents
4.4 Quantification of Process Vent Flows
4.5 Component Flammability Data Collection
4.6 Identification of Operating Scenarios
4.7 Quantification of Flammability Characteristics for Combined Vents
4.8 Identification, Quantification and Assessment of Possibility of Air Ingress Routes
4.9 Tabulation of Data
4.10 Hazard Study and Risk Assessment
4.11 Note on Aqueous / Organic Wastes
4.12 Complexity of Systems
4.13 Summary
5 SAFE DESIGN OF VENT COLLECTION HEADER SYSTEMS
5.1 General
5.2 Process Design of Vent Headers
5.3 Liquid in Vent Headers
5.4 Materials of Construction
5.5 Static Electricity Hazard
5.6 Diversion Systems
5.7 Snuffing Systems
6 SAFE DESIGN OF THERMAL OXIDISERS
6.1 Introduction
6.2 Design Basis
6.3 Types of High Temperature Thermal Oxidizer
6.4 Refractories
6.5 Flue Gas Treatment
6.6 Control and Safety Systems
6.7 Project Program
6.8 Commissioning
6.9 Operational and Maintenance Management
APPENDICES
A GLOSSARY
B FLAMMABILITY
C EXAMPLE PROFORMA
D REFERENCES
DOCUMENTS REFERRED TO IN THIS PROCESS GUIDE
TABLE
1 PHOTOCHEMICAL OZONE CREATION POTENTIAL REFERENCED
TO ETHYLENE AS UNITY
FIGURES
1 SCHEMATIC OF TYPICAL VENT COLLECTION AND THERMAL OXIDIZER SYSTEM
2 TYPICAL KNOCK-OUT POT WITH LUTED DRAIN
3 SCHEMATIC OF DIVERSION SYSTEM
4 CONVENTIONAL VERTICAL THERMAL OXIDIZER
5 CONVENTIONAL OXIDIZER WITH INTEGRAL WATER SPARGER
6 THERMAL OXIDIZER WITH STAGED AIR INJECTION
7 DOWN-FIRED UNIT WITH WATER BATH QUENCH
8 FLAMELESS THERMAL OXIDATION UNIT
9 THERMAL OXIDIZER WITH REGENERATIVE HEAT RECOVERY
10 TYPICAL PROJECT PROGRAM
11 TYPICAL FLAMMABILITY DIAGRAM
12 EFFECT OF DILUTION WITH AIR
13 EFFECT OF DILUTION WITH AIR ON 100 Rm³ OF FLAMMABLE GAS
BENFIELD LIQUOR: DETERMINATION OF IRON
SCOPE AND FIELD OF APPLICATION
This method is suitable for the determination of the total iron in Benfield liquor samples up to a concentration of approximately 100 ppm m/v.
Determination of Residue and Oil in Anhydrous AmmoniaGerard B. Hawkins
Plant Analytical Techniques
Determination of Residue and Oil in Anhydrous Ammonia
This method is suitable for the determination of residue and oil in anhydrous ammonia.
FIELD OF APPLICATION
This method may be applied to standard and premium grade anhydrous ammonia having residue content in the range 10-5000 micrograms per gram and oil content in the range l-500 micrograms per gram
Operational Problems
Catalytic Reactor Process - Prompt List
- Feed Issues:
- Pipe work type Issues
- Operational Issues
- Vessel Loading
- Vessel Designs
- Wider Process Issues
- Material Issues
- Discharge issues
- Things to look at
- Things to consider trying
0 INTRODUCTION
The four main sources of Fugitive Emissions on most plants are valves, machine seals, re-makable joints and pressure relief devices. Other possible sources include open-ended lines, sampling connections, drains and vents.
Sometimes special precautions are taken to minimize Fugitive Emissions, for example the use of bellows seal valves. However, generally no special precautions are taken and the subsequent Fugitive Emissions to atmosphere represent a significant amount of plant losses.
Regulatory requirements covering Fugitive Emissions exist in many countries and therefore a leak reduction program should be implemented. Fugitive Emissions also represent financial losses to the business as well as potential damage to the environment.
"SEDIMENTATION"
INTRODUCTION - THE PHENOMENON OF SEDIMENTATION
Sedimentation is the physical process whereby solid particles, of greater density than their suspending medium, will tend to separate into regions of higher concentration under the influence of gravity. As a solids/liquids separation technique it therefore possesses the great advantage of utilizing a natural, and therefore costless, driving force. This section of the suspension processing Guide is Intended to provide an Introduction to the science of the subject, and the means to judge where and how best to exploit sedimentation as a separation (or other processing) technique.
As a scientific discipline the subject of sedimentation is vast with perspectives ranging from the field of chemical engineering through to theoretical physics being covered In the literature [1-11]. Good reviews of the subject, with a bias towards the engineering aspects, have been written by Fitch and Koz [12, 13]. A short summary of some of the more relevant contributions from the literature is also provided in GBHE-SPG-PEG-302 “Basic Principles & Test Methods”, of the Suspensions Processing Guides.
.
The sedimentation process is traditionally divided into ..."
Process Synthesis
INTRODUCTION
1 A SUGGESTED GENERAL APPROACH
2 EXAMPLES OF PROCESS SELECTION
2.1 Harvesting and Thickening of Single Cell Protein
2.2 Dewatering of a Specialty Latex
3 REFERENCES
TABLES
1 THE ADVANTAGES AND DISADVANTAGES OF DIFFERENT RANGE OF PH FOR “PROTEIN” ORGANISM FLOCCULATION
2 THE ADVANTAGES AND DISADVANTAGES OF VARYING EXTENTS OF CELL BREAKAGES
3 PREDICTED AND OBSERVED FILTER CAKE SOLIDS CONTENTS FOR THE VARIOUS LATICES AFTER COAGULATION
FIGURES
1 THE “PROTEIN” BACTERIAL HARVESTING SYSTEM
2 PROCESS FOR MANUFACTURE OF CALCIUM CARBONATE FILTERS
3 H-ACID ISOLATION
4 A SUGGESTED APPROACH TO DETERMINING FEASIBLE PROCESS OPTIONS, AND OPERATING CONDITIONS FOR SEPARATION OF FINE SOLIDS FROM SUSPENSION
5 MODULI VERSUS SOLIDS CONTENT FORTYPICAL FORWARD FLOCCULATED “PROTEIN” SUSPENSIONS
6 DECISION TREE FOR SELECTION OF AS1 HARVESTING CONDITIONS WHEN PRINCIPAL CONSTRAINT CONCERNS THE DEGREE OF THICKENING REQUIRED IN THE CONCENTRATE
7 DECISION TREE FOR SELECTION OF AS1 HARVESTING CONDITIONS WHEN PRINCIPAL CONSTRAINT CONCERNS THE USE OF FLOTATION AS A UNIT OPERATION FOR THICKENING
8 DECISION TREE FOR SELECTION OF AS1 HARVESTING CONDITIONS WHEN PRINCIPAL CONSTRAINT CONCERNS THE QUALITY OF THE RECYCLED LIQUOR
9 MODULUS SOLIDS CONTENT CURVES FOR THEVARIOUS COAGULATED LATICES
Integration of Special Purpose Centrifugal Pumps into a ProcessGerard B. Hawkins
Integration of Special Purpose Centrifugal Pumps into a Process
CONTENTS
1 SCOPE
2 PRELIMINARY CHOICE OF PUMP
SECTION A - INLET CONDITIONS
Al Calculation of Basic Nett Positive Suction Head (NPSH)
A2 Correction to Basic NPSH for Temperature Rise at Pump Inlet
A3 Correction to Basic NPSH for Acceleration Head
A4 Calculation of Available NPSH
A5 Correction to NPSH for Fluid Properties
A6 Calculation of Suction Specific Speed
A7 Priming
A8 Submergence
SECTION B – FLOW / HEAD RATING SEQUENCE
B1 Calculation of Static Head
B2 Calculation of Margins for Control
B3 Calculation of Q-H Duty
B4 Stability and Parallel Operation
B5 Corrections to Q-H Duty for Fluid Properties
B6 Guide to Pump Type and Speed
SECTION C – DRIVER POWER RATING
C1 Estimation of Pump Efficiency
C2 Calculation of Absorbed Power
C3 Calculation of Driver Power Rating
C4 Preliminary Power Ratings of Electric Motors
C5 Starting Conditions for Electric Motors
C6 Reverse Flow and Reverse Rotation
SECTION D - CASING PRESSURE RATING
D1 Calculation of Maximum Inlet Pressure
D2 Calculation of Differential Pressure
D3 Pressure Waves
D4 Pressure due to Liquid Thermal Expansion
D5 Casing Hydrostatic Test Pressure
SECTION E – SEALING CONSIDERATIONS
E1 Preliminary Choice of Seal
E2 Fluid Attributes
E3 Definition of Flushing Arrangements
APPENDICES
A RELIABILITY CLASSIFICATION
B SYMBOLS AND PREFERRED UNITS
DOCUMENTS REFERRED TO IN THIS ENGINEERING DESIGN GUIDE
Determination of Hydrocarbons in Anhydrous Ammonia By Gas ChromatographyGerard B. Hawkins
Determination of Hydrocarbons in Anhydrous Ammonia By Gas Chromatography
SCOPE AND FIELD OF APPLICATION
The method is suitable for the determination of hydrocarbons from C1 to C4 (see 6.4.2) in gaseous ammonia, or in mixtures of ammonia and air. It is valid for concentrations in the range 10-10000 ppm.
The method may be used for the analysis of the atmosphere from a ships hold After purging with ammonia and for the analysis of gasified liquid anhydrous ammonia during or after loading. In these cases, hydrocarbon contamination may arise from the previous cargo of the vessel, the nature of which should be ascertained prior to carrying out the analysis
Carbon Formation in Mixed Feed Preheat Coils:
Maximum Mixed Feed Pre-heat Temperature
What follows is a crude but effective routine, which evaluates the maximum possible temperature allowable to prevent excessive carbon laydown in the mixed feed pre-heat coils.
Reactor Modeling Tools – Multiple Regressions
CONTENTS
0 INTRODUCTION
1 SCOPE
2 THEORY
3 EXCEL 2007: MULTIPLE REGRESSIONS
3.1 Overview
3.2 Multiple Regression Using the Data Analysis ADD-IN
3.3 Interpret Regression Statistics Table
3.4 Interpret ANOVA Table
3.5 Interpret Regression Coefficients Table
3.6 Confidence Intervals for Slope Coefficients
3.7 Test Hypothesis of Zero Slope Coefficients ("Test of Statistical Significance")
3.8 Test Hypothesis on a Regression Parameter
3.8.1 Using the p-value approach
3.8.2 Using the critical value approach
3.9 Overall Test of Significance of the Regression Parameters
3.10 Predicted Value of Y Given Regressors
3.11 Excel Limitations
4 SPECIAL FEATURES REQUIRING MORE SOPHISTICATED TECHNIQUES
5 USER INFORMATION SUPPLIED
A SUBROUTINE
B DATA
C RESULTS
6 EXAMPLE
Determination of Argon in Ammonia Plant Process Gas Streams by Gas Chromatogr...Gerard B. Hawkins
Determination of Argon in Ammonia Plant Process Gas Streams by Gas Chromatography
SCOPE AND FIELD OF APPLICATION
This document is a method for the determination of argon in process gas streams in the range 0-10% v/v.
Determination of Carbon Dioxide, Ethane And Nitrogen in Natural Gas by Gas C...Gerard B. Hawkins
Determination of Carbon Dioxide, Ethane
And Nitrogen in Natural Gas by Gas Chromatography
1 SCOPE AND FIELD OF APPLICATION
This document is a method for the determination of carbon dioxide, ethane and nitrogen in natural gas in the range 0-10% v/v.
2 PRINCIPLE
The gas sample will be injected automatically by a ten port valve onto the poraplot U column. The nitrogen will elute first and be switched to the mole sieve column. The mole sieve column will be isolated and the poraplot column will elute the carbon dioxide and ethane via a restrictor column to the detector. After the elution of the carbon dioxide and ethane the poraplot column will be back flushed. Then the nitrogen will be allowed to elute from the mole sieve column (see figure 1.) ...
Determination of Anions by Ion Chromatography
1 SCOPE AND FIELD OF APPLICATION
This method is suitable for the determination of inorganic anions in Ammonia Solution in the range 100 ppb to 50 ppm m/v.
2 PRINCIPLE
The sample is passed through a column of anion exchange resin, on which the anions are absorbed and separated. They are then eluted with dilute sodium carbonate/sodium hydrogen carbonate solution and passed through a suppressor. This replaces the cations with hydrogen ions and thus reduces the background conductivity of the eluent. Final measurement is by conductivity
Application of Process to Management of Change and ModificationsGerard B. Hawkins
Application of Process to Management of Change and Modifications
Hazard Study Process: GBHE-PGP-006
CONTENTS
1.0 PURPOSE
1.1 THE NEED FOR MODIFICATIONS
1.2 GENERAL DESCRIPTION OF A MODIFICATION
1.3 PRINCIPLES TO BE FOLLOWED
1.4 REPLACEMENT OF ’LIKE WITH LIKE’
1.5 REMOTE / SMALLER SITES
1.6 GENERAL GUIDANCE TO INDIVIDUALS DOING SHE ASSESSMENTS FOR MODIFICATIONS
1.7 MODIFICATIONS HAZARD STUDY DECISION MECHANISM
1.7.1 Purpose
1.7.2 Methodology
FIGURE 1 MODIFICATION FLOWCHART
M1 Title, description, registration and process flowsheet
Gate 1 Preliminary authorization
Table 1 Difference between a Modification and a Project
M2 Risk Assessment
Gate 2 Approval
M3 Detailed design and implementation
Gate 3 Pre-Commissioning check
M4 Commissioning
Gate 4 Commissioned
M5 Final review and file
APPENDIX
APPENDIX A CHECKLIST FOR MODIFICATIONS
APPENDIX B DOCUMENTATION PROMPT LIST
APPENDIX C TYPICAL MODIFICATION FORM
G1 PRELIMINARY AUTHORIZATION
M2 PRELIMINARY SSHE ASSESSMENT
G2 REVIEW PRELIMINARY SSHE ASSESSMENT
M3 DESIGN and ESTIMATION
SSHE ASSESSMENT
G3 APPROVAL
M4 DETAILED DESIGN AND IMPLEMENTATION
G4 PRE-COMMISSIONING CHECK
M5 COMMISSIONING
G5 COMMISSIONED
M6 FINAL REVIEW AND FILE
Integration of Rotary Positive Displacement Pumps into a ProcessGerard B. Hawkins
Integration of Rotary Positive Displacement Pumps into a Process
This Engineering Design Guide deals with:
(a) The specification of the pump duty for enquiries to be sent to pump vendors,
(b) The estimation of the characteristics and requirements of the pumps in order to provide preliminary information for design work by others.
It applies to pumps in Group 2 and 3 as defined in GBHE-EDS-MAC-21 Series, and is also an essential preliminary step for a pump in Group 1 whose final duty is negotiated with the chosen pump supplier.
It may be used for general-purpose pumps in Group 4; their duties when used in a support role are often inadequately defined, whereupon such pumps can be specified by reference to the manufacturer's data for a pump satisfactorily fulfilling the same process need.
Study 1: Concept Hazard Review
CONTENTS
1.0 PURPOSE
1.0.1 Team
1.0.2 Timing
1.0.3 Preparation
1.0.4 Documentation
HAZARD STUDY 1: APPLICATION
1.1 Project Definition
1.2 Process Description
1.3 Materials Hazards
1.4 External Authorities
1.5 Organization and Human Factors
1.6 Additional Activities to be Completed
1.7 Review of Hazard Study 1
APPENDICES
A Chemical Hazard Guide Diagram
B Safety Risk Criteria - Limit Values for Tolerable Risk
C List of Additional Assessments
Tools for Reactor Modeling:
THE ELEMENT POTENTIAL METHOD FOR CHEMICAL EQUILIBRIUM ANALYSIS: STANJAN
CONTENTS
1 SCOPE
2 SUMMARY
3 INTRODUCTION
4 EXAMPLES
4.1 CARBON-RICH C-0 SYSTEM
4.2 EXAMPLE WITH TWO COMPLEX PHASES
4.3 GAS TURBINE ENGINE EXAMPLE
4.4 OTHER APPLICATIONS
APPENDIX
FIGURES
5.1 EXAMPLE RUN LOG FOR CARBON-RICH C-O SYSTEM
5.2 OUTPUT FOR EXAMPLE WITH TWO COMPLEX PHASES
5.3 FIRST STEP IN THE TURBINE EXAMPLE: CALCULATION OF THE ENTHALPY OF THE REACTANTS
5.4 SECOND STEP IN THE TURBINE EXAMPLE: CALCULATION OF THE ADIABATIC FLAME TEMPERATURE
5.5 THIRD STEP IN THE TURBINE EXAMPLE: CALCULATION OF THE NOZZLE EXIT STATE
AVAILABILITY AND IMPLEMENTATION OF STANJAN
REFERENCES
Use and Applications of Membranes
0 INTRODUCTION/PURPOSE
1 SCOPE
2 FIELD OF APPLICATION
3 DEFINITIONS
4 GENERAL
4.1 What is a Membrane Process?
4.2 What does a Membrane look like?
4.3 Why use Membranes?
4.4 Membrane Types and Polymers Used
5 REVERSE OSMOSIS
5.1 Principles of Reverse Osmosis
5.2 Limitations
5.3 Performance
5.4 Costs
5.5 Worked Example
5.6 Applications
6 MICROFILTRATION AND ULTRAFILTRATION
6.1 Microfiltration
6.2 Ultrafiltration
7 PERVAPORATION
7.1 Classes of Application
7.2 Characteristics
7.3 Costs
7.4 Example - Lurgi Design
7.5 Application - Stripping Organics from Water
8 GAS SEPARATION AND VAPOR PERMEATION
8.1 Gas Separation
8.2 Vapor Permeation
9 LESS COMMON MEMBRANE PROCESSES
9.1 Dialysis
9.2 Electrodialysis
9.3 Electrolysis
9.4 Salt Splitting
10 BIBLIOGRAPHY
TABLES
1 UTILITY CONSUMPTION AND COST COMPARISON
Synthesis Gas and Refinery Hydrogen Applications
Support balls or more accurately, support balls and hold-down balls will at times need to be specified to our customers. Advice may also be needed opposite the usage of meshes and hold-down screens. This brief report focuses on some key aspects to consider.
1. Support Balls
2. Hold-down Balls
3. Meshes over Exit Collector & Exit Screen
4. Hold-down Screens
5. Support and Hold-down Ball Compositions and Applications
6. High Surface Area Dust Collectors
Selection and Use of Printed Circuit Heat ExchangersGerard B. Hawkins
Selection and Use of Printed Circuit Heat Exchangers
0 INTRODUCTION/PURPOSE
1 SCOPE
2 FIELD OF APPLICATION
3 DEFINITIONS
4 CONSTRUCTION
5 HEAT TRANSFER AND PRESSURE DROP
6 FOULING
7 MECHANICAL AND MATERIALS ASPECTS
8 COMPACTNESS
9 FLEXIBILITY
10 COST
11 GBHE EXPERIENCE 5
12 BIBLIOGRAPHY
APPENDICES
A HEAT TRANSFER AND PRESSURE DROP IN
WAVY PASSAGES
Utilizing Tubular UF Membrane Filtration for Wastewater ReuseBerghof Membranes
Water is a valuable asset to any industry. Implementing an efficient wastewater reuse and treatment system will lower the dependency on fresh water sources.
Established in 1981,Greyhound Chromatography has been supplying high quality Chromatography consumables to Research and Analysis Laboratories around the world for 38 years. Greyhound's Managing Director, Paul Massie founded the company which operates from its UK warehouse and office facility, located in Birkenhead, Merseyside.
Greyhound supplies Certified Reference Standards and Materials, Research Chemicals; including Solvents and Reagents and Laboratory consumables. New products are constantly added to Greyhound's e-commerce website, be sure to register to the website to view product prices.
Greyhound’s extensive range covers all areas of Environmental, Petrochemical, Food, Fragrance, Forensics, Chemical and Pharmaceutical analysis, holding stock of many popular products for prompt delivery via our extensive logistics network.
General Water Treatment For Cooling Water
0 INTRODUCTION/PURPOSE
1 SCOPE
2 FIELD OF APPLICATION
3 DEFINITIONS
4 CHOICE OF COOLING SYSTEM
4.1 ‘Once through' Cooling Systems
4.2 Open Evaporative Recirculating Systems
4.3 Closed Recirculating Systems
4.4 Comparison of Cooling Systems
5 MAKE-UP WATER QUALITY
6 FOULING PROCESSES
6.1 Deposition
6.2 Scaling
6.3 Corrosion
6.4 Biological Growth
7 CONTROL OF THE COOLING SYSTEM
7.1 ‘Once through' Cooling Systems
7.2 Closed Recirculating Systems
7.3 Open Evaporative Cooling Systems
TABLES
1 RELATIVE IMPORTANCE OF FOULING PROCESSES AND INSTALLED COSTS
2 WATER QUALITY PARAMETERS
FIGURES
1 PREDICTION OF CALCIUM CARBONATE SCALING
2 CALCIUM SULFATE SOLUBILITY
3 CALCIUM PHOSPHATE SCALING INDEX
Membrane based water purification technology(ultra filteration,dialysis and e...Sanjeev Singh
This is made by keeping in mind needy students who want to know water purification technology.This slide contain brief description about membrane,ultra filtration,dialysis,electro dialysis.For further topic check my updates regularly....... .At last i would like to thanks those students who downloaded this slide.
SYNOPSIS
The principles underlying centrifugal separation of particulate species are briefly considered, and the main types of separator available are noted. The procedures available for scale-up from laboratory or semi-technical data are then discussed in detail with particular reference to perhaps the most important class of machine for fine particle processing: the disc-nozzle centrifuge.
Starting with the basic concepts behind their design, discussion follows to explain the factors which may limit centrifuge performance. It is shown how a few simple; laboratory scale tests can give a valuable insight into the design and operation of full-scale industrial machines.
Pipeline Design for Isothermal, Turbulent Flow of Non-Newtonian FluidsGerard B. Hawkins
Pipeline Design for Isothermal, Turbulent Flow of Non-Newtonian Fluids
0 INTRODUCTION/PURPOSE
1 SCOPE
2 FIELD OF APPLICATION
3 DEFINITIONS
4 DESCRIPTION OF ANOMALOUS EFFECTS
4.1 Wall Slip
4.2 Drag Reduction in Polymeric Materials
4.3 Transition Delay by Polymeric Materials
4.4 Drag Reduction in Suspensions
5 DESIGN PROCEDURE FOR PRESSURE DROP
IN TURBULENT PIPE FLOW IN THE ABSENCE
OF DRAG REDUCTION
5.1 Pressure Drop in the Absence of Wall Slip and
Drag Reduction
5.2 Wall Slip
5.3 Pipe Roughness
5.4 Pipe Fittings
6 DESIGN PROCEDURE FOR DRAG REDUCING
POLYMERIC MATERIALS
6.1 General
6.2 Transition Delay
6.3 Pipe Roughness
6.4 Pipe Fittings
7 DESIGN PROCEDURE FOR DRAG REDUCING
FIBRE SUSPENSIONS
8 BIBLIOGRAPHY
9 NOMENCLATURE
FIGURES
1 DRAG REDUCTION PHENOMENA
2 TRANSITION DELAY PHENOMENA
3 PROCEDURE FOR THE CALCULATION OF
PRESSURE DROP IN TURBULENT NON-NEWTONIAN
PIPE FLOW
4 TYPICAL RELATIONSHIP FOR Ψ VERSUS ʋ*
Membrane filtration by Akram Hossain, Food and Process Engineering, HSTUAkram Hossain
This presentation explains about membrane filtration and its type. I collected information from different source and accumulated to make this. Hope you will find it useful.
PRACTICAL GUIDE ON THE REDUCTION OF DISCHARGES TO ATMOSPHERE OF VOLATILE ORGA...Gerard B. Hawkins
PRACTICAL GUIDE ON THE REDUCTION OF DISCHARGES TO ATMOSPHERE OF VOLATILE ORGANIC COMPOUNDS (VOCs)
FOREWORD
CONTENTS
1 INTRODUCTION
2 THE NEED FOR VOC CONTROL
3 CONTROL AT SOURCE
3.1 Choice or Solvent
3.2 Venting Arrangements
3.3 Nitrogen Blanketing
3.4 Pump Versus Pneumatic Transfer
3.5 Batch Charging
3.6 Reduction of Volumetric Flow
3.7 Stock Tank Design
4 DISCHARGE MEASUREMENT
4.1 By Inference or Calculation
4.2 Flow Monitoring Equipment
4.3 Analytical Instruments
4.4 Vent Emissions Database
5 ABATEMENT TECHNOLOGY
5.1 Available Options
5.2 Selection of Preferred Option
5.3 Condensation
5.4 Adsorption
5.5 Absorption
5.6 Thermal Incineration
5.7 Catalytic Oxidation
5.8 Biological Filtration
5.9 Combinations of Process technologies
5.10 Processes Under Development
6 GLOSSARY OF TERMS
7 REFERENCES
Appendix 1. Photochemical Ozone Creation Potentials
Appendix 2. Examples of Adsorption Preliminary Calculations
Appendix 3. Example of Thermal Incineration Heat and Mass Balance
Appendix 4. Cost Correlations
Similar to Other Separations Techniques for Suspensions (20)
Pressure Relief Systems Vol 2
Causes of Relief Situations
This Volume 2 is a guide to the qualitative identification of common causes of overpressure in process equipment. It cannot be exhaustive; the process engineer and relief systems team should look for any credible situation in addition to those given in this Part which could lead to a need for pressure relief (a relief situation).
Pressure Relief Systems
BACKGROUND TO RELIEF SYSTEM DESIGN Vol.1 of 6
The Guide has been written to advise those involved in the design and engineering of pressure relief systems. It takes the user from the initial identification of potential causes of overpressure or under pressure through the process design of relief systems to the detailed mechanical design. "Hazard Studies" and quantitative hazards analysis are not described; these are seen as complementary activities. Typical users of the Guide will use some Parts in detail and others in overview.
GAS DISPERSION - A Definitive Guide to Accidental Releases of Heavy GasesGerard B. Hawkins
GAS DISPERSION - A Definitive Guide to Accidental Releases of Heavy Gases
This Process Safety Guide has been written with the aim of assisting process engineers, hazard analysts and environmental advisers in carrying out gas dispersion calculations. The Guide aims to provide assistance by:
• Improving awareness of the range of dispersion models available within GBHE, and providing guidance in choosing the most appropriate model for a particular application.
• Providing guidance to ensure that source terms and other model inputs are correctly specified, and the models are used within their range of applicability.
• Providing guidance to deal with particular topics in gas dispersion such as dense gas dispersion, complex terrain, and modeling the chemistry of oxides of nitrogen.
• Providing general background on air quality and dispersion modeling issues such as meteorology and air quality standards.
• Providing example calculations for real practical problems.
SCOPE
The gas dispersion guide contains the following Parts:
1 Fundamentals of meteorology.
2 Overview of air quality standards.
3 Comparison between different air quality models.
4 Designing a stack.
5 Dense gas dispersion.
6 Calculation of source terms.
7 Building wake effects.
8 Overview of the chemistry of the oxides of nitrogen.
9 Overview of the ADMS complex terrain module.
10 Overview of the ADMS deposition module.
11 ADMS examples.
12 Modeling odorous releases.
13 Bibliography of useful gas dispersion books and reports.
14 Glossary of gas dispersion modeling terms.
Appendix A : Modeling Wind Generation of Particulates.
APPENDIX B TABLE OF PROPERTY VALUES FOR SPECIFIC CHEMICALS
Theory of Carbon Formation in Steam Reforming
Contents
1 Introduction
2 Underpinning Theory
2.1 Conceptualization
2.2 Reforming Reactions
2.3 Carbon Formation Chemistry
2.3.1 Natural Gas
2.3.2 Carbon Formation for Naphtha Feeds
2.3.3 Carbon Gasification
2.4 Heat Transfer
3 Causes
3.1 Effects of Carbon Formation
3.2 Types of Carbon
4 What are the Effects of Carbon Formation?
4.1 Why does Carbon Formation Get Worse?
4.1.1 So what is the Next Step?
4.2 Consequences of Carbon Formation
4.3 Why does Carbon Form where it does?
4.3.1 Effect on Process Gas Temperature
4.4 Why does Carbon Formation Propagate Down the Tube?
4.4.1 Effect on Radiation on the Fluegas Side
4.5 Why does Carbon Formation propagate Up the Tube?
5 How do we Prevent Carbon Formation
5.1 The Role of Potash
5.2 Inclusion of Pre-reformer
5.3 Primary Reformer Catalyst Parameters
5.3.1 Activity
5.3.2 Heat Transfer
5.3.3 Increased Steam to Carbon Ratio
6 Steam Out
6.1 Why does increasing the Steam to Carbon Ratio Not Work?
6.2 Why does reducing the Feed Rate not help?
6.3 Fundamental Principles of Steam Outs
TABLES
1 Heat Transfer Coefficients in a Typical Reformer
2 Typical Catalyst Loading Options
FIGURES
1 Hot Bands
2 Conceptual Pellet
3 Naphtha Carbon Formation
4 Heat Transfer within an Reformer
5 Types of Carbon Formation
6 Effect of Carbon on Nickel Crystallites
7 Absorption of Heat
8 Comparison of "Base Case" v Carbon Forming Tube
9 Carbon Formation Vicious Circle
10 Temperature Profiles
11 Carbon Pinch Point
12 Carbon Formation
13 Effect on Process Gas Temperature
14 How does Carbon Propagate into an Unaffected Zone?
15 Movement of the Carbon Forming Region
16 Effect of Hot Bands on Radiative Heat Transfer
17 Effect of Potash on Carbon Formation
18 Application of a Pre-reformer
19 Effect of Activity on Carbon Formation
Ammonia Plant Technology
Pre-Commissioning Best Practices
GBHE-APT-0102
PICKLING & PASSIVATION
CONTENTS
1 PURPOSE OF THE WORK
2 CHEMICAL CONCEPT
3 TECHNICAL CONCEPT
4 WASTES & SAFETY CONCEPT
5 TARGET RESULTS
6 THE GENERAL CLEANING SEQUENCE MANAGEMENT
6.6.1 Pre-cleaning or “Physical Cleaning
6.6.2 Pre-rinsing
6.6.3 Chemical Cleaning
6.6.4 Critical Factors in Cleaning Success
6.6.5 Rinsing
6.6.6 Inspection and Re-Cleaning, if Necessary
7 Systems to be treated by Pickling/Passivation
Ammonia Plant Technology
Pre-Commissioning Best Practices
Piping and Vessels Flushing and Cleaning Procedure
CONTENTS
1 Scope
2 Aim/purpose
3 Responsibilities
4 Procedure
4.1 Main cleaning methods
4.1.1 Mechanical cleaning
4.1.2 Cleaning with air
4.1.3 Cleaning with steam (for steam networks only)
4.1.4 Cleaning with water
4.2 Choice of the cleaning method
4.3 Cleaning preparation
4.4 Protection of the devices included in the network
4.5 Protection of devices in the vicinity of the network
4.6 Water flushing procedure
4.6.1 Specific problems of water flushing
4.6.2 Preparation for water flushing
4.6.3 Performing a water flush
4.6.4 Cleanliness criteria
4.7 Air blowing procedure
4.7.1 Specific problems of air blowing
4.7.2 Preparation for air blowing
4.7.3 Performing air blowing
4.7.4 Cleanliness checks
4.8 Steam blowing procedure
4.8.1 Specific problems of steam blowing
4.8.2 Preparation for steam blowing
4.8.3 Performing steam blowing
4.8.4 Cleanliness checks
4.9 Chemical cleaning procedure
4.9.1 Specific problems of cleaning with a chemical solution
4.9.2 Preparation for chemical cleaning
4.9.3 Performing a chemical cleaning
4.9.4 Cleanliness criteria
4.10 Re-assembly - general guideline
4.11 Preservation of flushed piping
PRACTICAL GUIDE ON THE SELECTION OF PROCESS TECHNOLOGY FOR THE TREATMENT OF A...Gerard B. Hawkins
PRACTICAL GUIDE ON THE SELECTION OF PROCESS TECHNOLOGY FOR THE TREATMENT OF AQUEOUS ORGANIC EFFLUENT STREAMS
CONTENTS
0 INTRODUCTION/PURPOSE
1 SCOPE
2 FIELD OF APPLICATION
3 DEFINITIONS
3.1 IPU
3.2 AOS
3.3 BODs
3.4 COD
3.5 TOC
3.6 Toxicity
3.7 Refractory Organics/Hard COD
3.8 Heavy Metals
3.9 EA
3.10 Biological Treatment Terms
3.11 BATNEEC
3.12 BPEO
3.13 EQS/LV
3.14 IPC
3.15 VOC
3.16 F/M Ratio
3.17 MLSS
3.18 MLVSS
4 DESIGN/ECONOMIC GUIDELINES
5 EUROPEAN LEGISLATION
5.1 General
5.2 Integrated Pollution Control (IPC)
5.3 Best Available Techniques Not Entailing Excessive Costs (BATNEEC)
5.4 Best Practicable Environmental Option (BPEO)
5.5 Environmental Quality Standards(EQS)
6 IPU EXIT CONCENTRATION
7 SITE/LOCAL REQUIREMENTS
8 PROCESS SELECTION PROCEDURE
8.1 Waste Minimization Techniques (WMT)
8.2 AOS Stream Definition
8.3 Technical Check List
8.4 Preliminary Selection of Suitable Technologies
8.5 Process Sequences
8.6 Economic Evaluation
8.7 Process Selection
APPENDICES
A DIRECTIVE 76/464/EEC - LIST 1
B DIRECTIVE 76/464/EEC - LIST 2
C THE EUROPEAN COMMISSION PRIORITY CANDIDATE LIST
D THE UK RED LIST
E CURRENT VALUES FOR EUROPEAN COMMUNITY ENVIRONMENTAL QUALITY STANDARDS AND CORRESPONDING LIMIT VALUES
F ESTABLISHED TECHNOLOGIES
G EMERGING TECHNOLOGY
H PROPRIETARY/LESS COMMON TECHNOLOGIES
J COMPARATIVE COST DATA
Getting the Most Out of Your Refinery Hydrogen PlantGerard B. Hawkins
Getting the Most Out of Your Refinery Hydrogen Plant
Contents
Summary
1 Introduction
2 "On-purpose" Hydrogen Production
3 Operational Aspects
4 Uprating Options on the Steam Reformer
4.1 Steam Reforming Catalysts and Tube Metallurgy
4.2 Oxygen-blown Secondary Reformer
4.3 Pre-reforming
4.4 Post-reforming
5 Downstream Units
6 Summary of Uprating Options
7 Conclusions
Amine Gas Treating Unit - Best Practices - Troubleshooting Guide Gerard B. Hawkins
Amine Gas Treating Unit Best Practices - Troubleshooting Guide for H2S/CO2 Amine Systems
Contents
Process Capabilities for gas treating process
Typical Amine Treating
Typical Amine System Improvements
Primary Equipment Overview
Inlet Gas Knockout
Absorber
Three Phase Flash Tank
Lean/Rich Heat Exchanger
Regenerator
Filtration
Amine Reclaimer
Operating Difficulties Overview
Foaming
Failure to Meet Gas Specification
Solvent Losses
Corrosion
Typical Amine System Improvements
Degradation of Amines and Alkanolamines during Sour Gas Treating
APPENDIX
Best Practices - Troubleshooting Guide
Burner Design, Operation and Maintenance on Ammonia PlantsGerard B. Hawkins
Burner Design, Operation and Maintenance on Ammonia Plants
Brief History
Reformer Burner Types/Design
Types of Reformers
Combustion Characteristics
Excess Air/Heater Efficiency
Maintenance, Good Practice
Low Nox Equipment
Summary
DEACTIVATION OF METHANOL SYNTHESIS CATALYSTS
CONTENTS
1 INTRODUCTION
2 THERMAL SINTERING
3 CATALYST POISONING
4 REACTANT INDUCED DEACTIVATION
5 SUMMARY
TABLES
1 DEACTIVATION PROCESSES ON METHANOL SYNTHESIS CATALYSTS
2 MELTING POINT, HUTTIG AND TAMMANN TEMPERATURES OF COPPER, IRON AND NICKEL
3 SINTERING RATE CONSTANTS CALCULATED INLET AND OUTLET SIDE STREAM UNIT FOR VULCAN VSG-M101
4 COMPARISON BETWEEN CALCULATED S∞ AND DISCHARGED MEASUREMENTS ON VULCAN VSG-M101
5 EFFECT OF POSSIBLE CONTAMINANTS AND POISONS ON CU/ZNO/AL2O3 CATALYSTS FOR METHANOL SYNTHESIS
6 GUARD SCREENING TEST RESULTS ON METHANOL MICRO-REACTOR. EFFECT OF DEPOSITED METALS ON METHANOL ACTIVITY
FIGURES
1 THE HΫTTIG AND TAMMANN TEMPERATURES OF THE COMPONENTS OF A SYNTHESIS CATALYST
2 A SCHEMATIC REPRESENTATION OF TWO CATALYST SINTERING MECHANISMS
3 SIDE STREAM DATA FOR VULCAN VSG-M101. INLET TEMPERATURE 242 OC, PRESSURE 1500 PSI, GAS COMPOSITION 6% CO, 9.2% CO2, 66.9% H2, 2.5% N2 AND 15.4% CH4, SPACE VELOCITY 17,778 HR-1. MEAN OUTLET TEMPERATURE 280 OC
4 TEMPERATURE DEPENDENCE OF THE RATE OF SINTERING
5 MECHANISM OF SULFUR RETENTION
6 CORRELATION OF SULFUR CAPACITY WITH TOTAL SURFACE AREA
7 EFFECT OF DEPOSITED (NI+FE) PPM ON METHANOL SYNTHESIS CATALYST ACTIVITY
8 DISCHARGED (FE + NI) DEPOSITION LEVELS ON METHANOL SYNTHESIS PLANT SAMPLES
9 EPMA ANALYSIS OF DISCHARGED LABORATORY SAMPLE OF POISONED VULCAN VSG-M101
10 THE EFFECT OF CO2 ON SYNTHESIS CATALYST DEACTIVATION
REFERENCES
Generating a custom Ruby SDK for your web service or Rails API using Smithyg2nightmarescribd
Have you ever wanted a Ruby client API to communicate with your web service? Smithy is a protocol-agnostic language for defining services and SDKs. Smithy Ruby is an implementation of Smithy that generates a Ruby SDK using a Smithy model. In this talk, we will explore Smithy and Smithy Ruby to learn how to generate custom feature-rich SDKs that can communicate with any web service, such as a Rails JSON API.
Smart TV Buyer Insights Survey 2024 by 91mobiles.pdf91mobiles
91mobiles recently conducted a Smart TV Buyer Insights Survey in which we asked over 3,000 respondents about the TV they own, aspects they look at on a new TV, and their TV buying preferences.
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
https://sectrio.com/resources/ot-threat-landscape-reports/sectrio-releases-ot-ics-and-iot-security-threat-landscape-report-2024/
DevOps and Testing slides at DASA ConnectKari Kakkonen
My and Rik Marselis slides at 30.5.2024 DASA Connect conference. We discuss about what is testing, then what is agile testing and finally what is Testing in DevOps. Finally we had lovely workshop with the participants trying to find out different ways to think about quality and testing in different parts of the DevOps infinity loop.
Slack (or Teams) Automation for Bonterra Impact Management (fka Social Soluti...Jeffrey Haguewood
Sidekick Solutions uses Bonterra Impact Management (fka Social Solutions Apricot) and automation solutions to integrate data for business workflows.
We believe integration and automation are essential to user experience and the promise of efficient work through technology. Automation is the critical ingredient to realizing that full vision. We develop integration products and services for Bonterra Case Management software to support the deployment of automations for a variety of use cases.
This video focuses on the notifications, alerts, and approval requests using Slack for Bonterra Impact Management. The solutions covered in this webinar can also be deployed for Microsoft Teams.
Interested in deploying notification automations for Bonterra Impact Management? Contact us at sales@sidekicksolutionsllc.com to discuss next steps.
Transcript: Selling digital books in 2024: Insights from industry leaders - T...BookNet Canada
The publishing industry has been selling digital audiobooks and ebooks for over a decade and has found its groove. What’s changed? What has stayed the same? Where do we go from here? Join a group of leading sales peers from across the industry for a conversation about the lessons learned since the popularization of digital books, best practices, digital book supply chain management, and more.
Link to video recording: https://bnctechforum.ca/sessions/selling-digital-books-in-2024-insights-from-industry-leaders/
Presented by BookNet Canada on May 28, 2024, with support from the Department of Canadian Heritage.
The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
All these questions and more will be explored as we talk about matching clients’ needs with what your agency offers without pulling teeth or pulling your hair out. Practical tips, and strategies for successful relationship building that leads to closing the deal.
Connector Corner: Automate dynamic content and events by pushing a buttonDianaGray10
Here is something new! In our next Connector Corner webinar, we will demonstrate how you can use a single workflow to:
Create a campaign using Mailchimp with merge tags/fields
Send an interactive Slack channel message (using buttons)
Have the message received by managers and peers along with a test email for review
But there’s more:
In a second workflow supporting the same use case, you’ll see:
Your campaign sent to target colleagues for approval
If the “Approve” button is clicked, a Jira/Zendesk ticket is created for the marketing design team
But—if the “Reject” button is pushed, colleagues will be alerted via Slack message
Join us to learn more about this new, human-in-the-loop capability, brought to you by Integration Service connectors.
And...
Speakers:
Akshay Agnihotri, Product Manager
Charlie Greenberg, Host
GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using Deplo...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
1. GBH Enterprises, Ltd.
Suspensions Processing Guide:
GBHE SPG PEG 309
Other Separations Techniques for
Suspensions
Process Disclaimer
Information contained in this publication or as otherwise supplied to Users is
believed to be accurate and correct at time of going to press, and is given in
good faith, but it is for the User to satisfy itself of the suitability of the Product for
its own particular purpose. GBHE gives no warranty as to the fitness of the
Product for any particular purpose and any implied warranty or condition
(statutory or otherwise) is excluded except to the extent that exclusion is
prevented by law. GBHE accepts no liability for loss, damage or personnel injury
caused or resulting from reliance on this information. Freedom under Patent,
Copyright and Designs cannot be assumed.
Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
Activation Reduction In-situ Ex-situ Sulfiding Specializing in Refinery Process Catalyst Performance Evaluation Heat & Mass
Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance
Characterization Refining & Gas Processing & Petrochemical Industries Catalysts / Process Technology - Hydrogen Catalysts /
Process Technology – Ammonia Catalyst Process Technology - Methanol Catalysts / process Technology – Petrochemicals
Specializing in the Development & Commercialization of New Technology in the Refining & Petrochemical Industries
Web Site: www.GBHEnterprises.com
2. Process Engineering Guide:
Other Separations Techniques
for Suspensions
CONTENTS
1
1.5
1.6
PRESSURE-DRIVEN MEMBRANE SEPARATION
PROCESSES
INTRODUCTION
MEMBRANES
OPERATION
FACTORS AFFETCING PERFORMANCE
1.4.1 Polarization / Fouling
1.4.2 Pressure
1.4.3 Crossflow
1.4.4 Temperature
1.4.5 Concentration
1.4.6 Membrane Pore Size
1.4.7 Particle Size
1.4.8 Particle Charge
1.4.9 Other Factors
ADVANTAGES / LIMITATIONS
SUMMARY OF SYMBOLS USED
2
ELECTRODIALYSIS
2.1
2.2
2.3
2.4
INTRODUCTION
EQUIPMENT
IMPORTANT PARAMETERSIN ED
EXAMPLES
3
ELECTRODEWATERING AND ELECTRODECANTATION
3.1
3.2
3.3
3.4
INTRODUCTION
PRINCIPLES AND OPERATION
EQUIPMENT AND OPERATING PARAMETERS
EXAMPLES
4
MAGNETIC SEPARATION METHODS
5
REFERENCES
1.1
1.2
1.3
1.4
Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
Activation Reduction In-situ Ex-situ Sulfiding Specializing in Refinery Process Catalyst Performance Evaluation Heat & Mass
Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance
Characterization Refining & Gas Processing & Petrochemical Industries Catalysts / Process Technology - Hydrogen Catalysts /
Process Technology – Ammonia Catalyst Process Technology - Methanol Catalysts / process Technology – Petrochemicals
Specializing in the Development & Commercialization of New Technology in the Refining & Petrochemical Industries
Web Site: www.GBHEnterprises.com
3. FIGURES
1
APPLICATION RANGES FOR MEMBRANE SEPARATION
TECHNIQUES
2
SIMPLE UF / CMF RIG
3
FLUX VERSUS TIME
4
FLUX VERSUS PRESSURE
5
ELECTRODIALYSIS PROCESS
6
ELECTRODIALYSIS PLANT FOR BATCH PROCESS
7
DEPENDENCE OF MEMBRANE AREA AND ENERGY ON
CURRENT DENSITY
8
DIFFUSION ACROSS THE BOUNDARY LAYER
Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
Activation Reduction In-situ Ex-situ Sulfiding Specializing in Refinery Process Catalyst Performance Evaluation Heat & Mass
Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance
Characterization Refining & Gas Processing & Petrochemical Industries Catalysts / Process Technology - Hydrogen Catalysts /
Process Technology – Ammonia Catalyst Process Technology - Methanol Catalysts / process Technology – Petrochemicals
Specializing in the Development & Commercialization of New Technology in the Refining & Petrochemical Industries
Web Site: www.GBHEnterprises.com
4. 1
PRESSURE-DRIVEN MEMBRANE SEPARATION
PROCESSES
1.1
INTRODUCTION
The term "pressure driven membrane separation processes" covers three closely
related unit operations, namely, Reverse osmosis, Ultrafiltration and Crossflow
Microfiltration. All three use a semipermeable membrane to effect the separation
and a pressure gradient as the driving force, they also use crossflow, feed
pumped at high velocity across the membrane surface, to minimize the
accumulation of rejected molecules/particles on the membrane. The difference
between the techniques lies in the structure of the membranes and the sizes of
the molecules/particles rejected by them. The molecule/particle size ranges for
the application of these techniques are shown in Figure 1.
In reverse osmosis transport through the membrane is by a solution diffusion
mechanism. Particles, inorganic salts and organic molecules with molecular
weights greater than a few hundred are rejected by the membrane. With its
"tight" membranes with inherent low water flux, reverse osmosis has little use in
suspension processing and will not be considered further.
In both ultrafiltration (UF) and crossflow microfiltration (CMF) transport through
the membrane is via pores so separation is on the basis of molecule/particle size.
The pore size can be controlled during manufacture to give a range of
membranes with different separation capabilities. Applications within GBHE for
these techniques include desalting dyestuff suspensions, concentrating polymer
latex and removing (and recovering) toxic materials from effluent streams.
These techniques are mainly used for processing aqueous solutions and
suspensions. However, the development in recent years of membranes and
systems with greater chemical resistance has widened their potential area of
application to many other solvents.
Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
Activation Reduction In-situ Ex-situ Sulfiding Specializing in Refinery Process Catalyst Performance Evaluation Heat & Mass
Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance
Characterization Refining & Gas Processing & Petrochemical Industries Catalysts / Process Technology - Hydrogen Catalysts /
Process Technology – Ammonia Catalyst Process Technology - Methanol Catalysts / process Technology – Petrochemicals
Specializing in the Development & Commercialization of New Technology in the Refining & Petrochemical Industries
Web Site: www.GBHEnterprises.com
5. 1.2
MEMBRANES
One obvious difference between UF and CMF is in the general structure of the
membranes and the range of pore sizes available.
All polymeric UF membranes are of the asymmetric type first developed by Loeb
and Sourirajan in the early Sixties [1]. These membranes are of the order of 100
micron thick. On one surface of the membrane there Is a thin layer (the “active"
layer) about 1 micron thick with small pores. The size of the pores in the active
layer, in the range 10 to 200 Angstrom for commercial UF membranes,
determines the separating capability of the membrane. The rest of the membrane
has larger pores in a spongy structure and acts as a support for the active layer.
The original membranes were cast from cellulose acetate but many current
membranes are made from polymers with greater chemical and temperature
resistance including polyacrylonitrile, polyamide, and polysulfone and
polyvinylidene difluoride. Ceramic UF membranes with a metal oxide layer on a
porous carbon support are also available. These have good chemical and
temperature resistance but are expensive and not widely used at the time of
writing.
UF membranes can be cast in tubular or flat sheet form. In tubular form the
active layer is always on the inner surface. Small diameter (~ 1 mm) membrane
tubes, known as hollow fibers, are self-supporting. Supported tubular membranes
are available up to 25 mm diameter. Several membrane tubes in parallel can be
enclosed in a common permeate shroud to make a commercial UF module. The
smaller diameter tubes give greater membrane area per unit volume of module
but need to be made into shorter modules because of higher pressure drops
along the tubes. With the smallest diameter tubes an in-line coarse filter Is also
advisable to avoid blockage problems when processing suspensions. Supported
flat sheet membranes with associated feed and permeate channels can be built
into stacks. A flat sheet membrane with feed and permeate channels can also be
rolled up ‘Swiss roll” style to make a spiral wound module. These have good
membrane area per unit module volume but the spacer matrix in the feed
channel could cause blockage problems with suspensions.
CMF membranes are thicker than UF membranes, about 1000 micron, and have
a uniform porous structure. This structure is somewhat analogous to sintered
metal. In fact some CMF systems use sintered stainless steel “membranes".
However, polymeric CMF membranes can be made from polyethylene,
polypropylene and polyamide with much higher porosities than sintered metals.
These membranes are available in pore sizes down to 1 micron for metals and
0.1 micron for polymers.
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6. These are usually available in self-supporting tubular form in diameters between
1 and 10 mm. As with UF a number of parallel membrane tubes are enclosed in
a common permeate shroud to make a module. The big advantage of CMF
membranes is that they are back flushable. A short pressure pulse can be
applied periodically to reverse the permeate flow. When this happens particles
that have penetrated into the membrane matrix are ejected back into the feed
stream and particle layers that have formed on the membrane surface are
disrupted.
The membrane differences detailed above should not be considered absolute.
Asymmetric membranes can be made with pore sizes in the CMF range.
However these usually have lower surface porosities than equivalent CMF
membranes and cannot be back flushed. UF membranes in the self-supporting
hollow fibre configuration are back flushable, but other UF membranes may be
damaged if this is attempted.
1.3
OPERATION
In general the operation of both UF and CMF systems is similar. A simple rig
suitable for feasibility testing or batch operation is shown in Figure 2.
Suspension is pumped from a reservoir through the UF/CMF module and the
concentrated suspension returned to the reservoir. Since crossflow velocities (210 m/s) are much higher than permeate velocities (< 0.01 m/s) many passes are
required to give significant concentration. Module inlet pressures can be up to 10
bar for UF and 5 bar for CMF. System pressure can be controlled by a back
pressure valve at the outlet of the module. The permeate is normally piped to a
storage tank or to drain but can be returned to the reservoir during constant
concentration trials. For back flushing (usually only with CMF modules) the valve
in the permeate line is closed and a compressed air pressure pulse (a few psi
above system pressure) is applied to the permeate in the module shroud for 0.5 10 seconds. For washing applications wash liquid can be added to the reservoir
at a rate equal to the permeate rate.
The Initial target of a feasibility trial is to find out if the required separation can be
achieved by UF/CMF. If successful the effect on flux of variations in pressure,
crossflow, temperature and concentration can then be investigated. If possible a
variety of membranes and module geometries should be tested. Al though some
extrapolation from steady state conditions is possible long term effects can only
really be determined by long term trials.
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7. Increasing the flux means a smaller membrane area requirement and a smaller
plant. However, this is often only achieved by increasing energy Input (pumping
or heating). Optimum operating conditions are determined by balancing capital
and operating costs.
UF and CMF plants are designed to be modular. Capacity can be increased by
adding more membrane modules as long as the pumps and pipework can handle
the extra flows involved. A single stage plant (Figure 2) can be operated
batchwise or continuously in a feed and bleed mode. However, for continuous
operation it is usually more efficient to have several stages with the concentrate
from one stage becoming the feed for the next.
1.4
FACTORS AFFETCING PERFORMANCE
The important performance parameter is the rate at which permeate passes
through the membrane, i.e. the flux. In Europe this is normally quoted in liters of
permeate per square meter of membrane per hour (1 m-2 hr-1). Although some of
the parameters that affect flux have been modeled individually, it is not yet
possible to predict the flux that will be obtained when a particular suspension is
processed in a particular membrane module. Factors that influence flux include:
1.4.1 Polarization / Fouling
The flux obtained when an aqueous suspension is treated by UF/CMF is
always lower than the pure water flux, often by an order of magnitude or
more. This flux reduction is due to membrane fouling which can be defined
as the accumulation of deposits on or in the membrane. Fouling occurs
through polarization, bacterial growth on the membrane and various
suspension/membrane interactions. Although polarization reaches
equilibrium rapidly other fouling mechanisms tend to occur, decline with
time. Decline to an uneconomic level may take a few hours or many
months. The fouling rate will depend on suspension characteristics,
membrane characteristics and operating conditions.
Regular back flushing can improve the flux temporarily but an overall
decline with time is still usually observed (Figure 3). Fouling can
sometimes be reduced by pre-treating the suspension. For example, a
change in pH may have a beneficial effect on suspension characteristics.
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8. A different membrane material may be less prone to fouling. Altering
operating conditions can also reduce fouling. A reduction in operating
temperature or pressure will reduce Initial flux but overall flux with time
may be improved if fouling is inhibited.
Alternatively, when an uneconomic flux is reached the process can be
stopped and the membranes cleaned. Chemical cleaning is usually the
most effective but larger bore membrane tubes can be cleaned physically
in situ. A recent BIOSEP SAR report deals exclusively with the cleaning of
membranes [8].
In addition to reducing flux fouling may have a secondary effect as the
fouling layer can become the separating medium. Solutes or particles
which pass freely through the membrane may be partially or even totally
rejected by the fouling layer, thus changing the separation.
Polarization occurs when molecules/particles rejected by the membrane
concentrate at the membrane surface. Crossflow will minimize this
concentration but will never entirely eliminate it. Most polarization studies
have investigated the concentration of solutes at the membrane surface.
The solute concentration at the membrane surface quickly increases to a
maximum value when the solute precipitates or forms a thixotropic gel.
Gel formation is analogous to cake formation in conventional filtration. The
gel concentration will depend upon chemical and morphological properties
of the solute and may vary from 10 to 75%. Flux, J, under conditions of gel
polarization is described by the widely accepted Blatt [2] equation:
where Cg and Cb are the suspended solid concentrations in the gel and
the bulk respectively; ks is an empirical constant considered later.
With particulates diffusive back-transport may not be significant and
equation (1) will not apply. Constant pressure particulate filtration without
back-transport can sometimes be described by the well-known cake
filtration equation:
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9. (The derivation and interpretation of this equation is reviewed in Section
1.5.2(b)).
Schneider [3] suggests that initial flux decline in CMF can be described by
equation (2). However, as equation (2) infers that all particles convected to
the polarized layer are accumulated it is unlikely to apply in the crossflow
situation.
The Scour Model [4] is based on the analogy between suspension flow
across a filter cake and the motion of a sediment laden stream over a
layer settled sediment. For the UF/CMF of suspensions of the Scour
Model equates convective deposition and scour removal giving:
Although none of the above equations are entirely satisfactory they are
useful in relating flux to other parameters.
1.4.2 Pressure
Flux in UF and CMF can be described by a resistance in series
relationship:
where Rm and Rp are the medium and polarization resistance terms.
Pure water flux is proportional to pressure. With suspensions, increasing
pressure (and flux) tend to increase the polarized layer and hence
resistance. It is possible to reach a limiting flux where further increases in
pressure are matched by increases in Rp (see Figure 4). This is
analogous to the effects of solids compressibility during cake filtration on
the pressure-dependence of filtration rate (Section 3.5).
Many users advise running at low pressures as this has the added
advantage of avoiding fouling due to compaction of the polarized layer.
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10. 1.4.3 Crossflow
In general, flux can be increased by increasing crossflow velocity. The
Scour Model, equation (3), relates flux and crossflow. With bacterial
suspensions , Fane [4] showed that Initial flux was proportional to U’-0, as
expected. However, long term steady state flux was found to be
proportional to U2.4, This demonstrates the beneficial effect increased
crossflow velocity can have in reducing fouling rate.
1.4.4 Temperature
Flux through porous media can be described by Poiseuille’s Law:
(where the symbols are as defined in Section 1.5.2(b) (I)).
In UF/CMF flux has been shown experimentally to be inversely
proportional to permeate viscosity as predicted by this equation. For
aqueous suspensions increasing temperature will therefore Increase flux.
If increasing temperature also reduces suspension viscosity pumping
costs will be reduced.
In practice it may or may not be economic to heat the suspension but it is
certainly sensible to avoid cooling unless the suspension is thermally
unstable.
1.4.5 Concentration
Equation (1) predicts that flux is proportional to the log of concentration.
This is the generally accepted relationship and has been verified for a
number of suspensions [5].
Equation (3), however, which is probably more general for suspensions,
predicts a log/log relationship between flux and concentration. This has
also been demonstrated experimentally for a number of suspensions
[4].
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11. 1.4.6 Membrane Pore Size
From equation (5) it can be predicted that increasing pore size leads to a
dramatic increase in pure water flux (see Figure 1). Equation (4) shows
that this effect will be masked when processing suspensions as Rp
increases in relation to Rm. In practice it is normal to use the largest pore
size membrane which will retain the required components of the
suspension.
1.4.7 Particle Size
From filtration theory (see Section 1.5.2) the resistance of polarized solids,
Rp, can be written as:
where m is the mass of solids polarized over area, A,
The specific cake resistance, a, can be related to particle properties via
the Kozeny-Carman equation (Section 1.5.2(b) ):
(ds is the diameter of suspended particles)
Therefore as particle size increases, Rp decreases and flux increases
(from equation (4)). For solids small enough to experience diffusive backtransport equation (1) is more likely to apply.
For dilute solutions the diffusion constant,
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12. This predicts that flux decreases as particle size increases.
Fane [6] showed experimentally that as particle size increased from 0.025
micron to 20 micron UF flux passes through a minimum as polarization
control changed from diffusive (decreasing with particle size) to nondiffusive (increasing with particle size). The minima occurred at about 0.1
micron.
Particle size range and shape are also obviously important in determining
polarized layer permeability and flux. Their effect awaits investigation.
1.4.8 Particle Charge
Using monodisperse silica colloids of different zeta potentials, McDonogh
[7] has shown that particle charge has a substantial effect on the
permeability of polarized layers. An increase in zeta potential leads to a
decrease in specific cake resistance (presumably by increasing cake
porosity - see equation (7)). The theory developed breaks down at low
zeta potentials (< 5 mV) where particles in the concentrated zone near the
membrane are highly likely to flocculate before laydown leading to larger
deposited particles and higher fluxes.
1.4.9 Other Factors
Hany other parameters relating to suspensions, membranes and operating
conditions can influence flux and require further investigation. For
example, Fane [4] has shown that particle rigidity and the presence of
macrosolutes are important. Charged membranes have shown some
promise in reducing fouling. Unfortunately, a full understanding of the
important parameters and the ability to predict and optimize flux are still a
long way off.
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13. 1.5
ADVANTAGES / LIMITATIONS
UF and CMF offer certain advantages over other filtration techniques.
These can be summarized as follows:(i)
They can be used to process suspensions of sub-micron particles
which are difficult or impossible to process by conventional
filtration, whilst avoiding the need to flocculate the system.
(ii)
As membranes with a range of pore sizes are available, dissolved
materials can be removed in the permeate or retained in the
suspension as required.
(iii)
Concentration can be carried out at ambient temperature offering a
significant energy advantage over evaporation techniques. Also,
labile materials can be processed without damage.
(iv)
The high crossflow velocities required make these techniques
particularly suitable for processing shear-thinning suspensions.
(v)
A controlled degree of suspension concentration may be achieved
(but see below).
Unfortunately there are certain limitations to the application of UF and MP:
(i)
Shear sensitive materials can be damaged.
(ii)
Polymer membranes can be damaged by freezing. The upper
temperature limit will be in the range 50-90 0C. pH tolerance may
be as much as 0.5 - 13 at room temperature but decreases
significantly at elevated temperatures. Surprisingly, the module
materials often have less temperature and chemical resistance than
the membranes themselves.
(iii)
Since crossflow is an essential feature of these techniques the
highest achievable solids concentration will be limited by
suspension rheology and module geometry (cf (v) above).
(iv)
The size of pores in the surface of an ideal UF/CMF membrane
would be monodisperse. In reality there is always a range of pore
sizes. Thus the molecule/particle size cut-off for membranes is
never sharp. This means that a molecule/particle size ratio of at
least 10 and preferably 100 is required to achieve good separation.
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14. For the future membrane separation is a fast developing area and significant
improvements can be expected in the next few years.
The biggest problem to be overcome is membrane fouling. This is a particular
problem in the biochemical area which offers membrane separation its largest
potential market. A membrane with greatly reduced susceptibility to fouling by
proteins is available but only for small laboratory-scale units. Further
developments in the area of antifouling membranes are anticipated. Relevant
research in this area has already been reviewed in Section 1.5 (see references
[39-44]1 of that section).
Little effort has been directed towards the optimization of module geometry in
terms of energy efficiency. Work is now in progress in this area but optimum
design may turn out to be highly feed dependent.
Membrane manufacturers will probably introduce membranes with greater
chemical resistance, higher fluxes and sharper cut-offs. This should allow UF and
CMF to be used in a wider range of applications.
1.6
SUMMARY OF SYMBOLS USED
A
Cb
Cg
D
dP
ds
J
Kb
Ke
Ks
l
n
N
N
ΔP
Rm
Rp
T
t
U
membrane area
bulk concentration
gel concentration
diffusion coefficient
pore diameter (average)
particle diameter
flux
Boltzmann's constant
Scour coefficient
mass transfer coefficient
pore length (including tortuosity factor)
mass of polarized solids
number of pores per unit area
layer thickness
pressure drop across membrane
membrane resistance
polarized layer resistance
absolute temperature
time
crossflow velocity
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15. V
a
ƹ
n
ρ
2
volume of permeate
specific cake resistance
porosity
viscosity of permeate
density
ELECTRODIALYSIS
2.1
INTRODUCTION
Under the influence of an electric field Ions in solution move towards the
electrodes where electrolysis takes place. If, however, membranes permeable
only to cations or anions are placed as barriers in the path of the migrating ions,
such that a series of compartments are formed, then it is possible to trap
electrolyte in some compartments whilst removing it from adjacent compartments
(see Figure 5).
This technique is termed electrodialysis (ED) [9] and was originally developed by
the water treatment industry as a means of purifying brackish supplies. In recent
years ED has been used in the food industry (whey processing), in recovery of
metals from electroplating solutions and in the de-ashing of pharmaceuticals.
Hence chemical processing by electrodialysis involves removing dissolved salts
from slurries or suspensions or from dissolved neutral molecules. The GBHE
Engineering Group has studied the application of ED to problems ranging from
the de-ashlng of catalyst slurries through biological and pharmaceutical materials
to the desalting of dyes. One of the essential criteria for such applications is that
the liquor to be treated should be capable of being pumped through the channels
of the ED stack without causing blockages. This requirement obviously
constrains the viscosity range of the fluid as well as limiting particle size, colloidal
stability and sedimentation characteristics.
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16. 2.2
EQUIPMENT
(i) Membrane Stack
The membrane stack forms the heart of an electrodialysis unit. It comprises a
number of repeating units or cell pairs (see Figure 5) sandwiched between
electrodes. The electrodes are separated from the main part of the stack by
electrode rinse compartments which carry away the waste products
generated by the electrode reactions. The unit is held together in the manner
of a filter press by metal strong backs.
A cell pair comprises a cation exchange membrane, a spacer, an anion
exchange membrane and a second spacer. The area of the membranes
ranges from a few centimetres square in small laboratory units to ~ 2 meters
square in commercial stacks. The number of cell pairs ranges from one in
small laboratory equipment to several hundred in the large commercial plants.
(ii) Membranes
Permselective ion exchange membranes are chemically very similar to ion
exchange resins. The most common types are based on a crosslinked
polystyrene matrix which has been sulfonated in the case of cation exchange
membranes or chloromethylated and quaternized in the case of anion
exchange membranes. Membranes based on other polymer substrates are
easily available.
In all cases the membranes are swollen by water and counter ions are able to
move freely throughout the matrix. In ionic solutions of less than ~0.2 M, coions are prevented from entering the membrane by Donnan exclusion. For
example, the transport number for cations in a cation exchange membrane is
typically greater than 0.9. (Similarly for anions in anion exchange
membranes.)
Non polar solutes may pass into or through the membrane depending on their
size and molecular weight and on the tightness of the membrane. All
membranes may be expected to block the transport of colloids or proteins.
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17. (iii) Spacers
Inter-membrane spacers serve to hold the membranes apart and define the
liquid flow across the membrane surface. Two main types are available.
Tortuous path spacers have been developed by the American company,
Ionics Inc. They consist of a narrow convoluted channel with cross braces.
The combined effect of high linear flow rate and the cross braces promotes
high mass transfer to the membrane surface.
Sheet flow spacers are generally used by Japanese and some European
manufacturers. The linear velocity and pressure drop across the spacer is
much lower than the case of tortuous path spacers. Turbulence and hence
mass transfer are promoted by a plastic mesh set into the spacer. This type of
spacer maximizes the area of membrane available for ion transfer but is more
liable to fouling by suspensions.
(iv) Hydraulics and DC Power Supply
The hydraulic and electrical circuits are schematically shown in Figure 6. The
voltage and current rating of the DC power supply will vary with the size of
membrane stack. Requirements may be estimated by assuming a maximum
potential difference of 2.5 volts per cell pair and a current requirement of 2040 m.A cm-2.
The pumping rates will also depend on stack size, but may be estimated
assuming required linear velocities in each compartment of 5-10 cm
sec-1 for sheet flow spacers and 20-40 cm sec-1 for tortuous path spacers.
2.3
IMPORTANT PARAMETERS IN ED
Electrodialysis is a process which depends on mass transfer at the
membrane surface. Several inter-related factors govern this process; these
are listed in Table 1.
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18. Table 1
2.3.1 Energy Demand and Stack Throughput
The area of membrane and the energy required for a particular separation are
interdependent. The cost of the equipment is closely related to the membrane
area while the power cost is proportional to the cell pair voltage.
The optimum cost for any separation can be determined by comparing plots
of energy per unit throughput against current density with plots of membrane
area against current density (Figure 7).
The optimum current density may be obtained from the expression:
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19. 2.3.2 Current Efficiency
Current or electrical efficiency is the proportion of the total charge passed
used to transport the required ionic species.
Poor current efficiency increases the membrane area required for the
separation and also results in higher energy costs.
Some of the factors influencing current efficiency include leakage currents in
manifolds, polarization at the membrane surface, breakdown of Donnan
exclusion and the presence of competing ions.
2.3.3 Concentration Polarization and Limiting Current Density
Concentration polarization occurs when the flux of Ions to and from the
membrane surface is insufficient to sustain the required current. Similar mass
limiting transport effects are experienced in other membrane processes, in
catalysis and in electrode reactions.
Polarization at the surface of ion exchange membranes arises from the fact
that the transport number of the counter Ion in the membrane is close to unity
whereas it only has approximately half this value in solution.
The flux of a cation through a cation exchange membrane, Jm+, Is given
by
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20. Obviously the total flux of the cation arriving at the membrane surface must be
equal to the flux through the membrane. The deficiency is made up by diffusional
flow across a depleted, stagnant boundary layer at the membrane surface.
Figure 8 illustrates this effect.
Clearly, a limiting condition occurs as the current density is increased. At the
limiting condition:
The current density at this point is termed the limiting current density. Any
attempt to increase the current density beyond this point results in concentration
polarization and excessive energy usage.
The onset of limiting conditions is dependent on the conductivity of the
electrolyte, spacer geometry and the velocity of the solution over the membrane
surf ace. To a first approximation the limiting conditions are described by the
expression:
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21. If the applied voltage is increased in an attempt to exceed the limiting current
density water splitting will occur. The effect of this process is to cause extremes
of pH at the surface of the membrane and to cause a reduction in current
efficiency. Extremes of pH may damage the membranes as well as affecting pH
sensitive materials in solution.
2.3.4 Water Transport and Non Polar Solute Transfer
Movement of water through the membranes occurs contiguously with ionic
transport. Net water transport is the sum of three processes, namely the
movement of Ionic hydration shells, osmosis due to concentration gradients and
electro-osmosis. The net water transport may not always be in the direction of
current flow.
Non polar materials dissolved in the process liquors may be transported across
the Ion exchange membranes, largely by this water flux. The actual amount of
transfer will depend upon the molecular weight of the solute. Species with
molecular weights greater than the low hundreds are less likely to pass through
the majority of ion exchange membranes, for example soluble dyes and sugars
may be successfully desalted.
Colloidal and suspended materials are unable to pass through the membrane but
may be deposited on the membrane surface causing fouling problems. For this
reason, when attempting to desalt suspensions of low dissolved solids content, it
is important to limit the applied electrical field gradient in order to prevent
electrophoretic membrane fouling. In addition high flow rates are often used to
promote turbulence and good mixing. The electrophoretic effect is put to use in
the technique of electrodecantation which will be separately described.
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22. 2.4 EXAMPLES
Two applications of electrodialysis in current GBHE process technology are of
interest. An electrodialysis operation was being employed to remove calcium ions
(and traces of HCl) from glucose solution in the Cellulose Hydrolysis
development project of a European Conglomerate. In addition the technique has
been used to desalt dyestuff suspensions [11]. Further details may be found in
the references.
3
ELECTRODEWATERING AND ELECTRODECANTATION
3.1
INTRODUCTION
Both techniques are practical manifestations of the application of electrophoresis
to large scale concentration of sols or suspensions. The two techniques differ
mainly in the configuration of the engineering that effects the electrophoreticallydriven separation. GBHE uses electrodecantation to concentrate PTFE
suspensions while the IEEE has expertise in application of these techniques to a
wide range of separation problems including the concentration of protein and
cellular material.
The main pre-requisite for these methods is a solution of low ionic strength
(typically < low-3 m).
3.2
PRINCIPLES AND OPERATION
An electrodecantation unit (see Figures 1 and 2 of Reference [12]) is basically a
tank with electrodes at either end or a large number of membranes interposed
between and parallel to the electrodes. When the unit is filled with a suspension
and the electric field is applied, charged particles move towards their opposite
poles. When the particles reach a membrane (the membrane acts as a physical
barrier to particles but conducts electricity) they pile up forming a dense layer
which then sediments. At a partner membrane particles are repelled forming a
less dense layer which gravitates to the surface. A flow pattern is established in a
membrane channel analogous to convection current. Thus a dense phase is
formed at the bottom of the unit and clear water at the top.
Both layers are drawn off and the cell volume is maintained by adding
suspension at the vertical midpoint of the tank.
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23. Other variations of the technique use moving membranes from which the
deposited material is removed with a doctor blade, or collecting laminae from a
stream flowing between electrodes.
3.3
EQUIPMENT AND OPERATING PARAMETERS
Electrodecantation typically uses GRP or similar tanks of 1-2 m3 capacity. The
membrane is generally cellulose acetate dialysis type sheet placed in the tank in
sheets, held apart by non-conductive rods. The electrodes may be any of the well
known coated types now available.
The range of final solids concentrations that can be handled is very much
controlled by the rheological properties of the slurry and may range from a few
percent for clay up to 60 or 70% for polymer latex.
Typical electrical field strengths lie in the region of 1 to 5 volts cm-1 while the
current density ranges from 1 to 10 mA cm-2.
3.4
EXAMPLES
Electrodewatering using the Dorr-Oliver Electrically-Assisted Vacuum Filtration
(EAVF) rig is currently being employed for PVC latex thickening on a Pilot Scale
at European Company [12]. It has also been considered as an isolation method
for certain fluoropolymer latex suspensions. This latter example illustrates an
important suspension processing strategy. EAVF is a valuable separation
technique for stable, colloidal suspensions where flocculation via addition of
surfactants, flocculants or salts is to be avoided. Thus polymer latex suspensions
whose intended use is for insulating materials are well dewatered by this means.
4 MAGNETIC SEPARATION METHODS
It has not proved possible to provide a contribution on the application of magnetic
methods of solid/liquid separation at this time. Since many of the potential outlets
for such methods are in Biotechnology, a useful introduction to the subject may
be found in the reference [13].
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24. Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
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25. Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
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26. Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
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27. Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
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28. Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
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29. Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
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Process Technology – Ammonia Catalyst Process Technology - Methanol Catalysts / process Technology – Petrochemicals
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30. Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
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