Purpose
Key to good performance
Problem Areas
Catalysts, heat shields and plant up-rates
Burner Guns
Development of High Intensity Ring Burner
Case Studies
Conclusions
Purpose
Key to good performance
Problem Areas
Catalysts, heat shields and plant up-rates
Burner Guns
Development of High Intensity Ring Burner
Case Studies
Conclusions
Look at two main types
Explain mechanisms
Explain prevention of cracking
Three main types
1 Carbon cracking
2 Boudouard carbon formation
3 CO reduction
Introduction High temperature shift Catalysts
Low temperature shift catalysts
Catalyst storage, handling, charging and discharging
Health and safety precautions
Reduction and start-up of high temperature shift catalysts
Operation of high temperature shift catalysts
Reduction and start-up of low temperature shift catalysts
Operation of low temperature shift catalysts
Need to remove poisons prior to entering downstream catalyst beds, including
Pre reformers
Primary reformers
HTS
LTS
Note : no Secondary - poisons do not stick as temperature is too high
Note that methanator is a purification step
Removes CO and CO2 which poisons synthesis catalyst
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
The Benefits and Disadvantages of Potash in Steam ReformingGerard B. Hawkins
Why do we include potash ?
What are the benefits ?
What are the disadvantages ?
Catalyst Deactivation
Carbon Deposition : Thermodynamics & Kinetics
Carbon formation margin
Reaction chemistry (Tube inlet)
Hydrocarbons undergo cracking reactions on hot surfaces at the tube inlet
Products of catalytic cracking reactions can form polymeric carbon
Introduction
Catalyst breakage is a well known phenomena that occurs during operation and transients such as reformer trips, whether this be due to,
• Normal in service breakage,
• Breakage due to carbon formation/removal,
• Breakage due to steam condensation or carry over,
• Breakage during a trip.
The effect of catalyst breakage can be observed in a number of ways,
• Hot bands,
• Speckling and giraffe necking,
• Catalyst breakage and settling.
VULCAN Series VSG-Z101 Primary Reforming
Initial Catalyst Reduction
Activating (reducing) the catalyst involves changing the nickel oxide to nickel, represented by:
NiO + H2 <==========> Ni + H2O
Natural gas is typically used as the hydrogen source. When it is, the catalyst reduction and putting the reformer on-line are accompanied in the same step.
1. Introduction reasons for purification, types of poisons, and typical systems
2. Hydrogenation
3. Dechlorination
4. Sulfur Removal
5. Purification system start-up and shut-down
Catalyst Catastrophes in Syngas Production - I
The Hazards
Review incidents by reactor
Purification….
Through the various unit operations to
Ammonia synthesis
Nickel Carbonyl
Pre-reduced catalysts
Discharging catalysts
Conclusion
Look at two main types
Explain mechanisms
Explain prevention of cracking
Three main types
1 Carbon cracking
2 Boudouard carbon formation
3 CO reduction
Introduction High temperature shift Catalysts
Low temperature shift catalysts
Catalyst storage, handling, charging and discharging
Health and safety precautions
Reduction and start-up of high temperature shift catalysts
Operation of high temperature shift catalysts
Reduction and start-up of low temperature shift catalysts
Operation of low temperature shift catalysts
Need to remove poisons prior to entering downstream catalyst beds, including
Pre reformers
Primary reformers
HTS
LTS
Note : no Secondary - poisons do not stick as temperature is too high
Note that methanator is a purification step
Removes CO and CO2 which poisons synthesis catalyst
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
The Benefits and Disadvantages of Potash in Steam ReformingGerard B. Hawkins
Why do we include potash ?
What are the benefits ?
What are the disadvantages ?
Catalyst Deactivation
Carbon Deposition : Thermodynamics & Kinetics
Carbon formation margin
Reaction chemistry (Tube inlet)
Hydrocarbons undergo cracking reactions on hot surfaces at the tube inlet
Products of catalytic cracking reactions can form polymeric carbon
Introduction
Catalyst breakage is a well known phenomena that occurs during operation and transients such as reformer trips, whether this be due to,
• Normal in service breakage,
• Breakage due to carbon formation/removal,
• Breakage due to steam condensation or carry over,
• Breakage during a trip.
The effect of catalyst breakage can be observed in a number of ways,
• Hot bands,
• Speckling and giraffe necking,
• Catalyst breakage and settling.
VULCAN Series VSG-Z101 Primary Reforming
Initial Catalyst Reduction
Activating (reducing) the catalyst involves changing the nickel oxide to nickel, represented by:
NiO + H2 <==========> Ni + H2O
Natural gas is typically used as the hydrogen source. When it is, the catalyst reduction and putting the reformer on-line are accompanied in the same step.
1. Introduction reasons for purification, types of poisons, and typical systems
2. Hydrogenation
3. Dechlorination
4. Sulfur Removal
5. Purification system start-up and shut-down
Catalyst Catastrophes in Syngas Production - I
The Hazards
Review incidents by reactor
Purification….
Through the various unit operations to
Ammonia synthesis
Nickel Carbonyl
Pre-reduced catalysts
Discharging catalysts
Conclusion
The courses, subjects, labs and projects that a student must undergo in order to become a Chemical Engineer.
We divide as follows:
4 blocks:
General Engineering
Theoretical Basis
Unit Operations
Plant Design/Operation
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).
Most modern ammonia processes are based on steam-reforming of natural gas or naphtha.
The 3 main technology suppliers are Uhde (Uhde/JM Partnership), Topsoe & KBR.
The process steps are very similar in all cases.
Other suppliers are Linde (LAC) & Ammonia Casale.
A Brief Introduction to Industrial boiler. And details about Boiler of Monnet Power Company Ltd(2X525 MW) Thermal Power Plant. Details about parts of Boiler, Water & Steam path, Oil Circuit, flue Gas Circuit.
(HTS) High Temperature Shift Catalyst (VSG-F101) - Comprehensiev OverviewGerard B. Hawkins
The high temperature shift duty introduction and theory
HTS catalyst characteristics
developments over time
Typical HTS operational problems
Improved catalysts
VULCAN Series VSG-F101 Series
Summary
I have attached this report where we find out the actual reason steam turbine Deaerating Condenser Performance degradation which was written on June 06, 2012.That time I was in Haripur Power Limited (HPL) ,A 360 MW CCPP of Pendekar Energy Bangladesh Ltd.
The report outcome showed that the Steam turbine load could be reached to its maximum capacity after those valve maintenance works on the next Steam Turbine Major inspection on 2013.We hope we can increase our steam turbine load to 5-7 MW/D on that time.
The operational guys were indicating Circulating water pumps (CWP A&B) were not performing to its design capacity & Ejectors/vacuum pumps are not performing well.So,Mechanical Maintenance Team (MMT) team find this successful outcome after several study.
Condenser vacuum condition has improved a lot after maintenance of the valves on last Major Inspection on 2013.
It is a sample report where we can realize that identifying actual reason for an equipment performance is not only a job of operational people but also a responsibility of the maintenance guys.
Super critical boiler manufacturing and working. Working cycle of Steam and water. Difference between sub critical and super critical boiler. Manufacturing process and definition of parts of boiler.
Steam Reforming - The Basics of reforming, shapes and carbon:
Steam Reforming Catalysis :
Chemical reactions
Catalyst shape design
Catalyst chemistry
Carbon formation and removal
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
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
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
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
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
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
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
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
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
UiPath Test Automation using UiPath Test Suite series, part 4DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 4. In this session, we will cover Test Manager overview along with SAP heatmap.
The UiPath Test Manager overview with SAP heatmap webinar offers a concise yet comprehensive exploration of the role of a Test Manager within SAP environments, coupled with the utilization of heatmaps for effective testing strategies.
Participants will gain insights into the responsibilities, challenges, and best practices associated with test management in SAP projects. Additionally, the webinar delves into the significance of heatmaps as a visual aid for identifying testing priorities, areas of risk, and resource allocation within SAP landscapes. Through this session, attendees can expect to enhance their understanding of test management principles while learning practical approaches to optimize testing processes in SAP environments using heatmap visualization techniques
What will you get from this session?
1. Insights into SAP testing best practices
2. Heatmap utilization for testing
3. Optimization of testing processes
4. Demo
Topics covered:
Execution from the test manager
Orchestrator execution result
Defect reporting
SAP heatmap example with demo
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
PowSyBl is an open source project hosted by LF Energy, which offers a comprehensive set of features for electrical grid modelling and simulation. Among other advanced features, PowSyBl provides:
- A fully editable and extendable library for grid component modelling;
- Visualization tools to display your network;
- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
What you will learn during the webinar:
- For beginners: discover PowSyBl's functionalities through a quick general presentation and the notebook, without needing any expert coding skills;
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Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
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.
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.
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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/
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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.
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3. Introduction
This presentation details some common problems that
can occur in a methanol synthesis loop.
Examples of Converter Problems
Example Operating Problems
Example Catalyst Problems
Some typical examples include, but are not limited to,
Rapid catalyst deactivation due to poisoning, Failure of
vessel components, High by-products levels, Temperature
excursions.
5. Quench Converter: “Cold Core” Problem
The term “Cold Core” usually refers to a problem observed
with the old Quench-style converter.
This traditional converter design (as shown on the right), in
which the synthesis reaction is quenched by the addition of
shots of cold gas between catalyst beds.
The quench is added to the gas reacting within the converter
by means of banks of transverse sparge pipes which have a
regular pattern of holes.
These spargers are in void space within a horizontal mesh
covered structure whose vertical shape is that of a lozenge
6. Quench Converter: “Cold Core” Problem
However, there have been problems due to the
phenomenon known as 'Cold Cores'.
This originates from portions of the catalyst that have a
high voidage and therefore a high gas flow whilst other
portions had a low voidage and therefore a low flow.
This causes a zone that is hot (due to low flow) and a
zone that is cold (due to high flow).
When shot is added to these hot and cold zones at an equal rate
through out the converter this causes a wide variation in the
temperature inlet the next bed. As there is essentially no cross
mixing within the converter, the effect passes down through the
whole converter leading to severe operational difficulties.
7. Quench Converter: Dust in Lozenges
Some quench converters suffered from blockage of the lozenge mesh,
see figure below which illustrates the design of the lozenge.
This can lead to problems of gas distribution between the hot bed exit
gas and cool shot gas.
This causes some problems in terms of operation since
such blockages prevented good mixing between the
effluent from the previous bed and the shot gas.
8. (TCC) Tube Cooled Converter Issue
A similar problem was also evident in early TCC (Tube Cooled
Converters), due to the spread of temperatures exit the tubes / inlet the
catalyst bed.
The problem here was that if the bed side temperature was
low due to high gas flowrates, then there would be a
localized reduction in the total heat transferred.
This causes a smaller than expected temperature rise up
the tubes, thereby reducing the inlet bed (turn)
temperature.
This causes the catalyst local to that tube to have a low
inlet temperature and therefore the bed temperatures will
be low.
9. (TCC) Tube Cooled Converter Issue
This problem was resolved through
design of a gas collection / mixing
device as shown to the right.
This then caused low tubeside
temperatures and a feedback loop
was developed.
The same effect occurred for zones
of low flow which led to high
temperatures etc.
10. (TCC) Tube Cooled Converter Design Issue
Generic Design
Tubesheet installed in the
bottom of the converter
Modified Design
11. (TCC) Tube Cooled Converter: Exit Collector
During the discharge of an Asia Pacific
Methanol Plant converter, it was found that the
mesh that should have been installed over the
exit collected had never been installed.
The collector consists (as illustrated to the
right) of a truncated cone which has 1 cm
wide holes in it side to allow for gas flow out
of the converter.
During the loading and normal operation, this cone was surrounded by
inert balls and therefore there was no catalyst ingress into the cone
and downstream outlet pipe.
12. (TCC) Tube Cooled Converter: Exit Collector
To rectify this situation, the outlet pipe had to
be cut and the catalyst emptied out; this spool
piece has been fitted with flanges.
Due to the problems associated with the
Manways (only 10” diameter), it has been
impossible to place a mesh over the outlet
collector and therefore at every catalyst
discharge the spool piece will have to be
removed.
14. Operational Problems: Temperature
Excursions
On a loop trip that affects the circulator, there will be complete loss of
circulation around the loop.
Since there is still hydrogen and carbon oxides in the converter at
high temperature, there will be some methanol synthesis.
These reactions cause a volume decrease as outlined below, and
there will be a pressure reduction which will in turn lead to further
reactants being sucked into the converter.
CO2 + 3H2 CH3OH + H2O ΔH = +49 kJ/kmol
4 volumes 2 volumes
CO + 2H2 CH3OH ΔH = +90 kJ/kmol
3 volume 1 volume
15. Operational Problems: Temperature
Excursions
At an Americas Methanol plant, during a plant trip,
there was a temperature excursion.
This plant had a
separate circulator
and synthesis gas
machine, but in this
case, the minimum
stop on the valve
downstream of the
saturator water
heater (see figure)
failed and closed
shut.
16. Operational Problems: Failure of Mesh on
Exit of Quench Converters
The outlet collector of the Quench Converter is
covered in a mesh to prevent catalyst passing
through the collector during discharge.
During normal operation, the collector is
surrounded by inert balls.
However, if the mesh fails, inert balls and
catalyst will be passed into the outlet pipe of
the reactor.
This will lead to very high pressure drop, which
will cause the plant to be shut down and then
synthesis catalyst to be changed out.
17. Operational Problems: Leakage of Balls from
ARC Bottom Beds
In ARC converters, there is a sealing
ring at the bottom of the converter
which is aimed at preventing inerts
balls and subsequently catalyst
passing into the outlet pipe work and
then on to downstream equipment.
This ring is not welded to the shell (an
important feature of the ARC converter
which makes it simple to install).
Catalyst Support
Plates Individual / Separate
Catalyst Beds
Gas Mixing
System
18. Operational Problems: Oil Leaks
Many circulators use oil on the
seals to prevent damage to the
shaft of the machine.
This oil can and does leak into the synthesis gas and is passed
to the converter where it is converted into longer chained
alkanes commonly known on methanol plants as waxes.
19. Operational Problems: Impingement
Corrosion
Severe corrosion can result from the high
velocity impingement of liquid droplets
entrained in a gaseous stream on a metal
surface, even though the environment would
not be considered corrosive under still
conditions.
Mild and low alloy steels are among the metals which are
particularly susceptible to this form of attack.
Problems can often be solved simply by upgrading to a higher alloy.
Conditions which could lead to impingement attack occur in those
parts of the loop where condensation takes place, or condensate is
present.
20. Operational Problems: Impingement
Corrosion
The actions which must be taken to eliminate
this problem are:
Reduction of gas velocity by increasing of
the inlet pressure to the compressor.
Adjusting the level within the MUG separator
to maximize efficiency.
Balancing the heat load in the cooler and
condenser prior to the MUG separator.
21. Operational Problems: Fouling of Crude
Cooler
There are two ways of fouling the crude
cooler.
The first is from wax formation which will
foul the tube side.
The second is from shell side fouling – normally due to
excessively high (50-60°C) return cooling water temperatures
leading to the hardness in the cooling water plating out on
the outside of the tubes
22. Operational Problems: Make Up Gas
Compositions
There is theoretical evidence that shows that synthesis
gases with high CO2 levels can lead to surface oxidation of
the methanol synthesis catalyst.
This in turn leads to an apparent loss of activity.
Comp Mole Frac (Methane) 0.111%
Comp Mole Frac (Nitrogen) 0.490%
Comp Mole Frac (Hydrogen) 69.028%
Comp Mole Frac (CO2) 6.054%
Comp Mole Frac (H2O) 0.094%
Comp Mole Frac (CO) 24.222%
23. Operational Problems: Boiler Feed Water
Quality
At a small South American methanol
plant there was a serious failure of the
tubes within their Steam Raising
Converter.
It was found that the cause was poor
boiler feed water quality which lead to
stress corrosion cracking of the tube
sheet to tube weld.
24. Operational Problems: Deposits on the
Synthesis Gas Machine and Circulator
At a South American methanol plant it was found that the
synthesis gas machine capacity was dropping; that is for a fixed
power usage, the flowrate through the machine dropped.
On inspection, it was found that there was a thick deposit on the
blades of the machine.
This was analysed and found to be a mixture of iron of nickel.
A similar effect was seen on the circulator.
25. Operational Problems: Methanol carryover
from catchpot
Some plants have suffered from liquid carry
over from the loop catchpot which can lead
to damage to the circulator.
This also increases the methanol content of
the gas entering the converter, thereby
giving a less favorable equilibrium position.
27. Low Activity
There are a number of reasons
for apparent low methanol
synthesis catalyst activity
including:
Poisoning
Poor catalyst loading
Excessive localized breakage leading to flow mal-
distribution.
Catalyst Problems
28. Catalyst Problems
Sintering
Sintering is caused by operation at high temperatures which causes
the migration of copper between crystallites which causes a loss of
copper surface area as illustrated below;
29. Catalyst Problems
Sintering
The activity of the catalyst is
proportional to copper surface
area, and therefore with time,
activity is lost.
0.175
0.275
0.375
0.475
0.575
0 12 24 36 48
Time Months
Activity
The figure illustrates the typical effect of temperature on activity
30. Catalyst Problems
Catalyst Breakage
Catalyst breakage does occurring during loading and operation,
however it is rare that the breakage is so bad that it affects
production.
There are of course some instances were catalyst breakage does
cause a problem.
31. Catalyst Problems
Byproducts
In the synthesis loop there are a number of by-products
formed, including,
Ethanol and higher alcohol’s such as propanol, butanol etc,
Dimethyl ether,
Acetone,
Ketones including Methyl Ethyl Ketone and Methyl Iso
Propanyl Ketone,
Methyl Formate,
Alkanes from heptane through to C40’s,
Methane.
32. Catalyst Problems
Byproducts
TMA
TMA or Tri Methyl Amine is a problem in the product
methanol since is gives the methanol a fishy smell –
methanol has a limit in all product specification that it
“shall be free from odour”.
TMA is formed by the reaction of ammonia produced in
the primary reformer with methanol formed in the loop.
33. Methanol Synthesis Catalyst: Poisoning
In order to avoid poisoning of the methanol synthesis catalyst, the following
limits MUST NOT be exceeded:
COMPONENT. LIMIT. Effect
Sulfur (as H2S). Such that the maximum accumulated S on the
catalyst charge be less than 0.20% of the total
mass of catalyst.
Poison
Chlorine (as HCl). Such that the maximum accumulated Cl on the
catalyst charge be less than 0.02% of the total
mass of catalyst.
Poison
Iron. Such that the maximum accumulated Fe on the
catalyst charge be less than 0.15% of the total
mass of catalyst.
Poison and wax
formation
Carbon
(elemental).
Absent. ∆P increase
Metals e.g. V, K,
Na.
Absent. Poisons
Nickel. Such that the maximum accumulated Ni on the
catalyst charge be less than 0.04% of the total
mass of catalyst.
Poison
Ammonia. 10 ppmv in the MUG. TMA formation
Ethene. 20 ppmv in the MUG.
Ethyne. 5 ppmv in the MUG.
Particulate
matter.
Absent. ∆P increase
Hydrogen
cyanide.
Absent. Poison
34. Methanol Synthesis Catalyst: Poisoning
Oxygen
Oxygen is not normally expected to be present in the
synthesis gas.
Although oxygen is not a catalyst poison, it is advised that the
level does not exceed 0.1% (molar) in the MUG, due to the
associated temperature rise and hydrogen consumption.
If the oxygen is present at a high enough level, it will lead to
bulk oxidation of the catalyst which will be seen as a loss of
apparent activity.
35. Methanol Synthesis Catalyst: Poisoning
Sulfur
There have been a
number of instances
of sulfur poisoning of
methanol synthesis
catalyst.
The mechanism of
sulfur poisoning is
highlighted
36. Methanol Synthesis Catalyst: Poisoning
DMS Formation
DMS or Dimethyl Sulfide can be formed by the reaction of
methanol with hydrogen sulfide.
This is normally a problem on methanol plants for the
reformer since there is methanol in the purge gas added
to the HDS section.
The DMS is formed over the HDS catalyst and ZnO but is
not removed in the ZnO bed. Therefore is passes straight
on to the primary reformer where it causes hot banding.
37. Methanol Synthesis Catalyst: Poisoning
Ni/Fe Carbonyl
Iron and nickel react with carbon monoxide, under certain
conditions, to form metal carbonyls.
As the reaction is exothermic and involves a reduction of
volume in forming Fe(C0)5 or Ni(CO)4, the equilibrium
concentration of carbonyl falls with rising temperature
and increases rapidly with pressure.
Against this, the rate of reaction increases with
temperature.
38. Methanol Synthesis Catalyst: Poisoning
Ni/Fe Carbonyl
At 1 bar partial pressure of CO the rate of formation of
carbonyl is at a maximum in the range 60-100°C, and
decomposition occurs at temperatures over 150° C.
At 10 bars partial pressure of CO the rate of formation
reaches a maximum at 180-190° C.
The maximum rate is also higher, but there should be no
significant nickel carbonyl formation above 250° C at low
pressures.
39. Methanol Synthesis Catalyst: Poisoning
Chloride Poisoning
Chlorides are a very severe
poison for methanol
synthesis catalyst, however,
it is rare that they are a
problem.
The figure illustrates the
mechanism,
40. Methanol Synthesis Catalyst: Poisoning
HDS Catalyst of Choice
Some methanol plants have experienced methanation of
the CO from the hydrogen recycle gas in the HDS vessel.
The recommended catalyst to be used is CoMO but some
plants have removed the HDS catalyst completely,
thereby leaving themselves vulnerable to poisoning by
organic sulfur compounds.
41. Methanol Synthesis Catalyst: Poisoning
Catalyst Discharge
Methanol synthesis catalyst in its
reduced form is pyrophoric and as such
will heat up very rapidly to 600°C or more
in the presence of air.
There have been numerous instances of such incidents during
catalyst discharge.
With the advent of discrete catalyst bed converters such as the ARC
and CMD converter, a requirement for a safer method of catalyst
discharge has developed.
42. Methanol Synthesis Loop: Common Problems
Problem Effect Solution
Low Circulation Rate High Converter Pressure Drop. Check valve position.
Check converter DPI meter
Mesh damage and catalyst passing
into outlet pipe.
Catalyst breakage.
Low Heat Recovery Fouling of Exchanger. Chemically clean exchanger.
Low exit converter temperature.
Too little gas through heat recovery
exchanger.
High Converter
Temperature Spreads
Cold Core. Raise converter temperature.
Change catalyst and ensure good
catalyst loading.
Instability ARC Low temperatures in converter – large ATE’s exit
bed 1.
Drop circulation rate. If this fails then
raise converter inlet temperature by
0.5°C.
Instability TCC Operating below minimum stability point. Raise turn temperature.
High Turn Temperature in
TCC and loss of
Production
Too high a recycle rate.
Too high a UA.
Gag in circulator.
Modify converter internals.
High Temperature on Trip Methanation. De-pressure on loop trip.
Valve failure.
Increasing Crude Cooler
Exit Temperature
Wax deposition.
Shell side fouling.
Reduce CW flow and raise exit
temperature.
Chemically clean shellside.
Maximise CW flow to keep return CW
temperature down.
Low Catalyst Activity Catalyst poisoning
Temperature excursions.
Check for sulphur/chlorides etc.
De-pressure loop on trip.
43. Conclusions
To conclude, a number of
potential issues have been
highlighted that can affect both
the hardware (equipment) and
the catalyst in the methanol
loop