The document discusses feedstock purification in hydrogen plants. It covers reasons for purification such as removing poisons from feedstocks that could damage catalysts. Typical purification systems involve hydrogenation, dechlorination and sulfur removal. Hydrogenation uses catalysts like CoMo or NiMo to react impurities like sulfur compounds and chlorides. Dechlorination requires removing chlorides before sulfur removal since chlorides can poison zinc oxide catalysts used for sulfur removal. Sulfur removal uses zinc oxide catalysts to absorb hydrogen sulfide and other sulfur compounds from feedstocks. The document provides details on typical purification processes and catalyst characteristics.
- Process effects of pre-reforming
- Process benefits of pre-reforming
- Effect of Pre-reformer Inlet Temp on Primary Reformer Efficiency
- Services for Pre-reforming
Pre-Reforming Problems
- Features: Impact of Sulfur
- High Temperature Operation
- Catalyst Deactivation
- Which is Better - High or Low Inlet Temperatures ?
- Pre Reformer Loading
- Pre-Reformer Installation
- Pre-reformer Startup
- Catalyst Drying
- Catalyst Heating
- Reduction
Look at two main types
Explain mechanisms
Explain prevention of cracking
Three main types
1 Carbon cracking
2 Boudouard carbon formation
3 CO reduction
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
- Process effects of pre-reforming
- Process benefits of pre-reforming
- Effect of Pre-reformer Inlet Temp on Primary Reformer Efficiency
- Services for Pre-reforming
Pre-Reforming Problems
- Features: Impact of Sulfur
- High Temperature Operation
- Catalyst Deactivation
- Which is Better - High or Low Inlet Temperatures ?
- Pre Reformer Loading
- Pre-Reformer Installation
- Pre-reformer Startup
- Catalyst Drying
- Catalyst Heating
- Reduction
Look at two main types
Explain mechanisms
Explain prevention of cracking
Three main types
1 Carbon cracking
2 Boudouard carbon formation
3 CO reduction
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
A full package presentation about Hydrogen Production Unit including an overview about steam reformers, combustion reaction, moods of heat transfer, draft systems, reactors, chemicals used in HPU, and types of compressors. Moreover, it describes the process description, process variables, and opens the way for some possible improvements which can be implemented to develop the unit performance.
Hydrogen Plant Flowsheet - Effects of Low Steam RatioGerard B. Hawkins
Effect of Low Steam Ratio on the Steam Reformer
Effect of Low Steam Ratio on H T Shift & PSA
Effect of Low Steam Ratio on Gross Efficiency
Effect of Low Steam Ratio on Net Efficiency
Alternative schemes for improving heat recovery
(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
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
Pre-reforming
Flow-schemes
Feed-stocks
Catalyst handling, loading & start-up
Benefits of a pre-reformer
Case studies
Effects upon primary reformer
Data analysis
Reactor temperature profiles
Catalyst management
Summary
Pre-reformer in the flowsheet
* positioned upstream of the steam reformer
* uses a specialized high activity catalyst based on Ni
* reaction involves conversion of hydrocarbons to a mix of CH4, CO, CO2 and H2
Pre-reformers - sometimes included at the original design stage
- also can be added to existing units to uprate the plant
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.
Catalyst Catastrophes in Syngas Production - II
Contents
Review of incidents by reactor
Primary reforming
Secondary reforming
HTS
LTS
Methanator
Reactor loading
Support media
Some general comments on alternative actions when a plant gets into abnormal operation
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
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
A full package presentation about Hydrogen Production Unit including an overview about steam reformers, combustion reaction, moods of heat transfer, draft systems, reactors, chemicals used in HPU, and types of compressors. Moreover, it describes the process description, process variables, and opens the way for some possible improvements which can be implemented to develop the unit performance.
Hydrogen Plant Flowsheet - Effects of Low Steam RatioGerard B. Hawkins
Effect of Low Steam Ratio on the Steam Reformer
Effect of Low Steam Ratio on H T Shift & PSA
Effect of Low Steam Ratio on Gross Efficiency
Effect of Low Steam Ratio on Net Efficiency
Alternative schemes for improving heat recovery
(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
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
Pre-reforming
Flow-schemes
Feed-stocks
Catalyst handling, loading & start-up
Benefits of a pre-reformer
Case studies
Effects upon primary reformer
Data analysis
Reactor temperature profiles
Catalyst management
Summary
Pre-reformer in the flowsheet
* positioned upstream of the steam reformer
* uses a specialized high activity catalyst based on Ni
* reaction involves conversion of hydrocarbons to a mix of CH4, CO, CO2 and H2
Pre-reformers - sometimes included at the original design stage
- also can be added to existing units to uprate the plant
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.
Catalyst Catastrophes in Syngas Production - II
Contents
Review of incidents by reactor
Primary reforming
Secondary reforming
HTS
LTS
Methanator
Reactor loading
Support media
Some general comments on alternative actions when a plant gets into abnormal operation
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
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
Common poisons include
Sulfur
Chlorides and other halides
Metals including arsenic, vanadium, mercury, alkali metals (including potassium)
Phosphates
Organo-metalics
Steam Reforming - The Basics of reforming, shapes and carbon:
Steam Reforming Catalysis :
Chemical reactions
Catalyst shape design
Catalyst chemistry
Carbon formation and removal
Conference for Catalysis Webinar 2021: "The Key Role of Catalysts and Adsorb...Dr. Meritxell Vila
Energy transition is a challenge for refineries and petrochemical plants. In this sense, the role of catalysts and adsorbents will be crucial in three areas:
New schemes of refineries: crude oil to chemicals (COTC)
Production of biofuels
Production of green hydrogen
This presentation was done at Catalysis Webinar 2021, the 24th March.
Introduction and Theoretical Aspects
Catalyst Reduction and Start-up
Normal Operation and Troubleshooting
Shutdown and Catalyst Discharge
Nickel Carbonyl Hazard
Modern Methanation Catalyst Requirements
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
SiGNa Oilfield Canada is a subsidiary of SiGNa Chemistry, a US-based manufacturer of stabilized alkali metals. Based in Calgary, SiGNa Oilfield Canada is committed to bringing innovative new chemical technologies to Canada's heavy oil market.
SiGNa's ActiveEOR® and ActiveSand® products are a new class of green chemicals that increase recovery from oil & gas reservoirs. SiGNa’s oil & gas products combine the benefits of chemical, immiscible gas, and thermal flooding techniques to give producers the advantages three oil recovery techniques from one easy-to-use, pumpable chemical. Silicides can be used as a standalone chemical or injected alongside other EOR techniques. Usable at any depth and with any viscosity, silicides generate heat, pressure, and silicates downhole, within the formation. No heat is lost on the surface and only minimal losses to the wellbore casing and tubing strings. These green chemicals produce only benign by-products and deliver cleaner wastewater, causing less impact on the environment.
This is great Presentation with 3D effects which is all about production of ammonia from natural gas.
I am damn sure you will be getting everything here searching for.
its better to download it and then run in powerpoint 2013.
Production of Syngas from biomass and its purificationAwais Chaudhary
This project includes production of syngas from biomass and its purification. Firstly we discuss feasibility and availability of raw material. Then we have literature survey. A lot of techniques are there to produce syngas, we have discuss process selection. Environmental considerations are also have been discussed. Piping and instrumentation (P&ID) diagrams also have been attached. At the end we've our conclusion and our recommendations.
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
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
GraphSummit Singapore | The Future of Agility: Supercharging Digital Transfor...Neo4j
Leonard Jayamohan, Partner & Generative AI Lead, Deloitte
This keynote will reveal how Deloitte leverages Neo4j’s graph power for groundbreaking digital twin solutions, achieving a staggering 100x performance boost. Discover the essential role knowledge graphs play in successful generative AI implementations. Plus, get an exclusive look at an innovative Neo4j + Generative AI solution Deloitte is developing in-house.
Securing your Kubernetes cluster_ a step-by-step guide to success !KatiaHIMEUR1
Today, after several years of existence, an extremely active community and an ultra-dynamic ecosystem, Kubernetes has established itself as the de facto standard in container orchestration. Thanks to a wide range of managed services, it has never been so easy to set up a ready-to-use Kubernetes cluster.
However, this ease of use means that the subject of security in Kubernetes is often left for later, or even neglected. This exposes companies to significant risks.
In this talk, I'll show you step-by-step how to secure your Kubernetes cluster for greater peace of mind and reliability.
zkStudyClub - Reef: Fast Succinct Non-Interactive Zero-Knowledge Regex ProofsAlex Pruden
This paper presents Reef, a system for generating publicly verifiable succinct non-interactive zero-knowledge proofs that a committed document matches or does not match a regular expression. We describe applications such as proving the strength of passwords, the provenance of email despite redactions, the validity of oblivious DNS queries, and the existence of mutations in DNA. Reef supports the Perl Compatible Regular Expression syntax, including wildcards, alternation, ranges, capture groups, Kleene star, negations, and lookarounds. Reef introduces a new type of automata, Skipping Alternating Finite Automata (SAFA), that skips irrelevant parts of a document when producing proofs without undermining soundness, and instantiates SAFA with a lookup argument. Our experimental evaluation confirms that Reef can generate proofs for documents with 32M characters; the proofs are small and cheap to verify (under a second).
Paper: https://eprint.iacr.org/2023/1886
Goodbye Windows 11: Make Way for Nitrux Linux 3.5.0!SOFTTECHHUB
As the digital landscape continually evolves, operating systems play a critical role in shaping user experiences and productivity. The launch of Nitrux Linux 3.5.0 marks a significant milestone, offering a robust alternative to traditional systems such as Windows 11. This article delves into the essence of Nitrux Linux 3.5.0, exploring its unique features, advantages, and how it stands as a compelling choice for both casual users and tech enthusiasts.
Alt. GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using ...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.
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.
Pushing the limits of ePRTC: 100ns holdover for 100 daysAdtran
At WSTS 2024, Alon Stern explored the topic of parametric holdover and explained how recent research findings can be implemented in real-world PNT networks to achieve 100 nanoseconds of accuracy for up to 100 days.
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.
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
Observability Concepts EVERY Developer Should Know -- DeveloperWeek Europe.pdfPaige Cruz
Monitoring and observability aren’t traditionally found in software curriculums and many of us cobble this knowledge together from whatever vendor or ecosystem we were first introduced to and whatever is a part of your current company’s observability stack.
While the dev and ops silo continues to crumble….many organizations still relegate monitoring & observability as the purview of ops, infra and SRE teams. This is a mistake - achieving a highly observable system requires collaboration up and down the stack.
I, a former op, would like to extend an invitation to all application developers to join the observability party will share these foundational concepts to build on:
UiPath Test Automation using UiPath Test Suite series, part 6DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 6. In this session, we will cover Test Automation with generative AI and Open AI.
UiPath Test Automation with generative AI and Open AI webinar offers an in-depth exploration of leveraging cutting-edge technologies for test automation within the UiPath platform. Attendees will delve into the integration of generative AI, a test automation solution, with Open AI advanced natural language processing capabilities.
Throughout the session, participants will discover how this synergy empowers testers to automate repetitive tasks, enhance testing accuracy, and expedite the software testing life cycle. Topics covered include the seamless integration process, practical use cases, and the benefits of harnessing AI-driven automation for UiPath testing initiatives. By attending this webinar, testers, and automation professionals can gain valuable insights into harnessing the power of AI to optimize their test automation workflows within the UiPath ecosystem, ultimately driving efficiency and quality in software development processes.
What will you get from this session?
1. Insights into integrating generative AI.
2. Understanding how this integration enhances test automation within the UiPath platform
3. Practical demonstrations
4. Exploration of real-world use cases illustrating the benefits of AI-driven test automation for UiPath
Topics covered:
What is generative AI
Test Automation with generative AI and Open AI.
UiPath integration with generative AI
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
2. Feedstock Purification in Hydrogen
Plants
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
GBH Enterprises Ltd.
3. 1. Reasons for Feedstock
Purification
Steam reforming catalyst requirements
• process gas feed to reformer (dry basis)
sulfur <0.1 ppmv: poison
chlorides <0.1 ppmv: poison
As/V/Pb/Hg <5ppbv: poison
olefins <1-2 vol %: carbon formation
LTS catalyst requirement
• process gas feed to LTS (dry basis)
chlorides <5 ppb: severe poison
sulfur <0.1 ppmv: poison
4. 1. Reasons for Feedstock
Purification
Steam reformer catalyst poisoning
• Increased methane slip
low plant efficiency
• Hot tubes
tube life reduction or failure
• Carbons formation
increased pressure drop
increased methane slip and hot tubes
• Sulfur poisoning can be recovered by
steaming the steam reforming catalyst
GBH Enterprises Ltd.
5. 1. Reasons for Feedstock
Purification
LTS catalyst poisoning
• Reduced life
premature plant S/D due to high Co slip
and high pressure drop
• Chloride deactivates catalyst at
concentrations of only 0.05 wt%
• Cu poisoning is not reversible
GBH Enterprises Ltd.
6. Natural Gas Feeds
Mercury may be present in some NG supplies
*H2S & reactive organic S compounds (odoring agents often added)
Component NG (mol %)
CH4 93.2
C2H6 4.8
C3H8 1.2
C4H10 0.4
C5+ 0.4
Total Sulfur* 2-20 ppmv
1. Sources of Poisons
GBH Enterprises Ltd.
9. Refinery Offgas Feeds (Contd.)
1. Sources of Poisons
COS may be present
• particularly if CO2 is present
Cl may be present as NH4Cl
Significant variation in poison content may
occur
• hydrogenation duty designed for peaks
• poisons absorption capacity designed for
average concentrations
GBH Enterprises Ltd.
10. Type of Sulfur Typical Split of S
(%)
H2S Trace
RSH 36
R2S2 3
R2S 51
*Unreactive S 10
Naphtha Feeds - Sulfur Species
* Stable > 400 Deg C (752 Deg F) - e.g. Thiophene
1. Sources of Poisons
GBH Enterprises Ltd.
11. Naphtha Feeds (Contd.)
1. Sources of Poisons
Large variation in S level
• 0.1 - 500 ppm wt
Chloride level typically 0.1 - 2 ppm wt
Pb/As/Va may be present
GBH Enterprises Ltd.
13. Feedstock Purification in Hydrogen
Plants
1. Introduction
Reasons for purification, types of
poisons, and typical systems
2. Hydrogenation
3. Dechlorination
4. Sulfur Removal
5. Purification system start-up and
shutdown
GBH Enterprises Ltd.
14. Hydrogenation Reactions
CoMo or NiMo type catalysts
Exothermic reactions, but little temperature
rise due to low concentrations
C2H5Cl + H2 C2H6 + HCl
C2H5SH + H2 C2H6 + H2S
C4H4S + 4H2 n-C4H10 + H2S
NH4Cl NH3 + HCl
Hydrogen requirement fixed by feed type
2. Hydrogenation
GBH Enterprises Ltd.
15. Feed Type Min H2
Requirement
(mol %)
Typical H2
Levels
(mol %)
NG 0 2-5
LPG 10 12
Light Naphtha 20 25
H. Naphtha
<20% Aromatics
25 25
H. Naphtha
>20% Aromatics
30 30
ROG feeds usually have sufficient hydrogen content
Hydrogenation Hydrogen Requirements
2. Hydrogenation
GBH Enterprises Ltd.
16. Feedstock Temperature
SOR
Temperature
EOR
ROG 370°C (698°F) 390°C (734°F)
*LPG 360°C (680°F) 380°C (716°F)
Naphtha 375°C (707°F) 400°C (752°F)
Hydrogenation Inlet Temperatures
- Lower inlet temperatures needed
C4s can crack more readily
2. Hydrogenation
GBH Enterprises Ltd.
17. 2. Typical Hydrogenation Catalyst
Characteristics - CoMo
Typical composition (wt %):-
CoO 4.0 %
MoO3 12.0 %
Cement Balance
Form:-
Usually extruded thin cylinders
with high porosity
A true catalyst!
GBH Enterprises Ltd.
18. 2. Hydrogenation - CoMo
Most common hydrogenation catalyst
Active in the sulfided state
Side reactions
• methanation
CO + 3H2 → CH4 + H2O
CO2 + H2 → CH4 + H2O
use NiMo if CO>3 vol% or CO2 >13 vol%
• hydrocracking
very low activity - carbon slowly formed
• can achieve very long lives
6-20 years
GBH Enterprises Ltd.
19. 2. Typical Hydrogenation Catalyst
Characteristics - NiMo
Typical composition (wt, loss free):-
NiO 4.0%
MoO3 14.0%
Cement Balance
Form:-
Usually extruded thin cylinders
with high porosity
A true catalyst!
GBH Enterprises Ltd.
20. 2. Hydrogenation - NiMO
Active in the sulfided state
Side reactions
• methanation suppressed when catalyst is
sulfided
• hydrocracking
low activity - carbon slowly formed (activity
marginally higher than CoMo)
Can achieve long lives (6-20 years)
Olefin hydrogenation activity slightly higher than
CoMo so NiMo usually chosen when olefin
concentration >1 vol%
GBH Enterprises Ltd.
21. 2. Hydrogenation
Typical operating conditions (CoMo &
NiMo):
• Operating temperature range
290-430OC (550-750OF)
• Operating pressure range
1 - 50 atm (15 psig - 750 psig)
• Space velocity
300 - 8000 hour-1
more typically 1000 - 4000 hour-1
GBH Enterprises Ltd.
22. 2. Hydrogenation
Organometallic compounds absorbed by
CoMo/NiMo
• approx. 1wt% of catalyst can be absorbed
• special catalyst grades exist that can
increase metals pick-up to approx. 2 wt%
useful for high Pb content naphthas
• extra catalyst design volume required
catalyst volume for metals absorption plus
catalyst volume for hydrogenation
GBH Enterprises Ltd.
23. 2. Hydrogenation
Low sulfur feeds
• CoMo/NiMo can over-reduce if S level
<1-2ppmv
permanent partial deactivation
• Hydrocracking
carbon formation
• Need to sulfur-inject if alternate S-
containing feeds are expected
• Equilibrium charts
GBH Enterprises Ltd.
24. 826 F 665 F1040 F 540 F
1/Temperature
Co
Mo
Ni
Sulfided Phase
Reduced
Phase
2. Co, Mo & Ni Sulfur Equilibrium
Phase Diagram
GBH Enterprises Ltd.
25. 2. Hydrogenation
Aromatics Hydrogenation
• Naphtha feeds contains aromatics
• Hydrogenation rate very slow over CoMo/NiMo
in reality - negligible
Olefin hydrogenation
• Maximum olefins to steam reformer = 1-2 vol%
• Hydrogen “consumption” needs to be taken
into account (increase hydrogen R/C”
• Temperature rise implications
re-circulation system can be used to limit
impact of temperature rise
GBH Enterprises Ltd.
27. 2. Hydrogenation
Reaction of COS over CoMo/NiMo
• COS is not absorbed by amine systems
• Low temperature operation
• At temperatures <290 OC (550 OF), then
hydrogenation activity is very low
• Catalysts containing higher active metal
contents May be used for temperatures
down to 240 OC (464 OF)
COS + H2O H2S + CO2
GBH Enterprises Ltd.
28. 2.Hydrogenation - Typical Problems
Pressure drop increase
carbon formation
• formed from hydrocarbon cracking
carry-over of solids
Sulfur slippage
low temperature of operation
• e.g. small plants with high heat loss
rate Increase
sulfur level increase
• very significant if sulfur is unreactive type
GBH Enterprises Ltd.
29. Feedstock Purification in Hydrogen
Plants
1. Introduction
2. Hydrogenation
3. Dechlorination
sources of chloride
effects of chloride
removal of chloride
4. Sulfur Removal
5. Purification system start-up & shut-
down
GBH Enterprises Ltd.
30. 3. Chloride Removal
Possible sources of chlorides
• offgas from certain catalytic reformer
plants
HCI & NH4Cl
• LPG and naphtha feeds
organic chlorides
Some chlorides might originate from the process
steam due to incorrect boiler feed water quality
control
GBH Enterprises Ltd.
32. 3. Chloride Removal
ZnO catalyst
• Some of the chlorides will react with the
ZnO to form ZnCl2
this significantly reduces the ZnO capacity
to absorb sulfur
weakens the catalyst
ZnCl2 sublimes at purification section
normal operating temperatures and can
deposit Zn and Cl on downstream reforming
catalyst
Why remove the chlorides before ZnO?
GBH Enterprises Ltd.
33. HClZnO
Crystallites
Catalyst
Pore
s
Effect of Chloride on ZnO Sulfur Removal Catalyst
1. Fresh ZnO 2. Poisoned
ZnCl2 blocks
catalyst surface
and pores to
prevent sulfur
absorption
3. Chloride Removal
GBH Enterprises Ltd.
34. HCl + NaAlO2 AlOOH + NaCl
2HCl + 2NaAlO2 Al2O3 + 2NaCl + H2O
Removing chlorides at elevated temperatures
requires a chemical absorbent
Physical absorbents like activated aluminas can not
operate at normal purification system temperatures
as absorbent must operate downstream of the
hydrogenation catalyst
Need to use a promoted alumina
- e.g. Na2O/Al2O3
3. Chloride Removal
GBH Enterprises Ltd.
35. 3. Chloride Removal - Operational
Aspects
Operation very straightforward
Temperature range
• 0 - 400OC (32 - 752OF)
Pressure range
• 0 - 50 atm (14 - 750 psig)
Space velocity
• experience of up to 10000/hr
• typically 1000-4000/hr
Absorbent sensitive to condensation
• pressure drop increase could be due to
condensation
GBH Enterprises Ltd.
36. • Design Cl slip = <0.1ppmv
• (Typically 0.05 ppmv or less)
• Monitor HCl slip on a regular basis
• If inlet chloride known, then life of catalyst can
be calculated approximately
• 12-14 weight % of chloride in catalyst
• High space velocities are possible
• Catalyst can be installed as a "ZnO" top-up
• Other Halogens
• Fluoride and bromide can also be removed
3. Chloride Removal
GBH Enterprises Ltd.
39. • Fe3O4 (reduced Fe2O3) not ideally suitable due
to high S slip
• ZnO used almost universally
“black” ZnO - Lower S capacity
H2S + ZnO H2O + ZnS
Mercaptans can also crack
C2H5SH + ZnO H2O + ZnS + C + CH4
4. Sulfur Removal
Chemical Reaction of H2S with absorbent
GBH Enterprises Ltd.
40. Typical compositions:-
1. ZnO 90-94.0 wt%
Cement Balance
2. ZnO 99 wt%
Forms:-
- Large variation
•Pelleted cylinders
•Extrudates
•Granulated spheres
Typical Sulfur Removal Catalyst
Characteristics
Target is to achieve maximum accessible ZnO
GBH Enterprises Ltd.
41. 4. Sulfur Removal - Total Pick-up
Catalyst requirements (high S pick-up)
• High porosity
allows access of H2S to centre of catalyst
pellet
porosity maintained as ZnO is converted to
ZnS
upstream chloride slip has lower effect on
catalyst S capacity
• Highly accessible surface area
sharp S absorption profile at high space
velocities
GBH Enterprises Ltd.
42. 4. Sulfur Removal - Operational
Aspects
Temperature range
• 300 - 400OC (572 - 752OF)
Pressure range
• 1 - 50 atm (14 - 750 psig)
Space velocity
• experience of up to 8000hr-1
• typically 500 - 4000hr-1
Sulfur slip
• usually designed for 0.1 ppmv sulfur
• achieved S slip <0.05 ppmv for fresh beds
GBH Enterprises Ltd.
43. 4. Sulfur removal - Monitoring and Life
Assessment
Monitor for H2S regularly
• daily for “stressed” beds (6 month lives)
• or daily/weekly
Also monitor other organic S compounds
• weekly
Note:- If average inlet S is known, life of ZnO can
be predicted using expected S pick-up value (eg
20-35 wt%) - NOT theoretical pick-up based on
ZnO quantity!
Monitoring still important
GBH Enterprises Ltd.
44. Temperature Affect on Total Sulfur Absorption
100 200 300 400
0
20
40
60
80
100
Temperature (°C)
Total amount of S absorbed prior to breakthrough. % theoretical
4. Sulfur removal - ZnO Absorbent Capacity
Low pressures (<12 bar, 17 psig) also decreases
total amount of S absorbed
GBH Enterprises Ltd.
45. 4. Sulfur Removal - Typical Problems
Premature sulfur slip
• check for organic S
CoMo/NiMo problems
• check for chlorides
an operating plant achieved only 2-5 wt% S
pickup with 1-2 ppmv Cl
• check for changes in feed sulfur specification
and operating conditions
higher space velocities will decrease original
predicted sulfur pick-up
Hot reformer tubes (hot bands etc)
• cross-check S analysis results!
GBH Enterprises Ltd.
46. Lead-Lag
• Series arrangement
• Configuration can be
reversed
• Upstream reactor can be
operated with H2S slip to
maximise S pick-up
• Catalyst bed changed
on-line
4. Sulfur removal - Series Beds
GBH Enterprises Ltd.
47. 4. Sulfur removal - Carbon Beds
Beds of activated carbon promoted with
copper
Carbon removes organic sulfur and
copper removes H2S
Regenerable
• Steam generation removes organic sulfur
• H2S can not be easily removed from Cu unless
steam/air regeneration used
• Effluent problems
H2S removal capabilities decrease with
time
GBH Enterprises Ltd.
48. Feedstock Purification in Hydrogen
Plants
1. Introduction
2. Hydrogenation
3. Dechloration
4. Sulfur Removal
5. Purification system start-up and
shut down
GBH Enterprises Ltd.
49. 5. Purification System Start-up
Usually heated-up with an inert gas or NG
• Heat up rate typically 50OC/hr (90OF/hr)
• If sour NG is used, avoid passing to the steam
reformer until conditions are reached for H2S
conversion and adsorption
For re -start of naphtha/LPG based plants,
ensure that the catalyst beds have been fully
purged of hydrocarbons before reformer is
brought on line
GBH Enterprises Ltd.
50. 5. Purification System - Start-up
CoMo/NiMo usually sulfided as hydrocarbon
feed is introduced
• In some cases, in situ pre-sulfiding may be
required
Feeds with high CO2/CO content
Sulfur-free C4 stream
Involves injection of carbon disulfide or
dimethyl disulfide etc in a flow of N2 or NG at
200OC (390OF)
Purification system usually effective at
reduced rates once 300OC (572OF) is achieved
• monitoring of S slip still important however
GBH Enterprises Ltd.
51. 5. Purification System - Shut-down
Beds should be purged with inert gas
cooling to < 38OC (100OF) before
depressurization
• For naphtha/LPG type feeds, if steam is
already isolated, purging should be done
to flare and not through the reformer
Discharged catalyst should be considered
pyrophoric
• Fine carbon, residual hydrocarbons & iron
carry-over
• During discharge, have water hoses ready
GBH Enterprises Ltd.
52. Purification Catalyst for Hydrogen
Plants - Summary
Types of poisons, required poison limits,
and typical purification systems
Hydrogenation
• CoMo/NiMo
• Aromatics and Olefin hydrogenation
• Sulfur equilibrium
• Dechlorination
• Sulfur removal
• Start-up and shut-down
GBH Enterprises Ltd.