Energy and Process Optimization for the Process Industries

FRANK (Xin X.) ZHU is a Senior Fellow at UOP LLC, where he has led innovation efforts to optimize industrial process design and operation to achieve higher energy efficiency and lower capital cost. Before joining UOP, Dr. Zhu served as a research professor at the Centre for Process Integration at the University of Manchester in the UK. He is also a former editor-in-chief of CACS Communications, the magazine of the Chinese-American Chemical Society.He is the recipient of the 2014 AIChE Energy and Sustainability Award.

• PREFACE xvPART 1 BASIC CONCEPTS AND THEORY 11 Overview of this Book 31.1 Introduction, 31.2 Who is this Book Written for?, 41.3 Five Ways to Improve Energy Efficiency, 51.4 Four Key Elements for Continuous Improvement, 71.5 Promoting Improvement Ideas in the Organization, 82 Theory of Energy Intensity 92.1 Introduction, 92.2 Definition of Process Energy Intensity, 102.3 The Concept of Fuel Equivalent (FE), 112.4 Energy Intensity for a Total Site, 132.5 Concluding Remarks, 153 Benchmarking Energy Intensity 163.1 Introduction, 163.2 Data Extraction from Historian, 173.3 Convert All Energy Usage to Fuel Equivalent, 173.4 Energy Balance, 213.5 Fuel Equivalent for Steam and Power, 233.6 Energy Performance Index (EPI) Method, 293.7 Concluding Remarks, 324 Key Indicators and Targets 354.1 Introduction, 354.2 Key Indicators Represent Operation Opportunities, 364.3 Define Key Indicators, 394.4 Set up Targets for Key Indicators, 454.5 Economic Evaluation for Key Indicators, 494.6 Application 1: Implementing Key Indicators into an "Energy Dashboard," 534.7 Application 2: Implementing Key Indicators to Controllers, 564.8 It is Worth the Effort, 57PART 2 ENERGY SYSTEM ASSESSMENT METHODS 595 Fired Heater Assessment 615.1 Introduction, 615.2 Fired Heater Design for High Reliability, 625.3 Fired Heater Operation for High Reliability, 685.4 Efficient Fired Heater Operation, 735.5 Fired Heater Revamp, 806 Heat Exchanger Performance Assessment 826.1 Introduction, 826.2 Basic Concepts and Calculations, 836.3 Understand Performance Criterion—U Values, 896.4 Understanding Pressure Drop, 946.5 Heat Exchanger Rating Assessment, 966.6 Improving Heat Exchanger Performance, 1067 Heat Exchanger Fouling Assessment 1127.1 Introduction, 1127.2 Fouling Mechanisms, 1137.3 Fouling Mitigation, 1147.4 Fouling Mitigation for Crude Preheat Train, 1177.5 Fouling Resistance Calculations, 1197.6 A Cost-Based Model for Clean Cycle Optimization, 1217.7 Revised Model for Clean Cycle Optimization, 1257.8 A Practical Method for Clean Cycle Optimization, 1287.9 Putting All Together—A Practical Example of Fouling Mitigation, 1308 Energy Loss Assessment 1388.1 Introduction, 1388.2 Energy Loss Audit, 1398.3 Energy Loss Audit Results, 1478.4 Energy Loss Evaluation, 1498.5 Brainstorming, 1508.6 Energy Audit Report, 1529 Process Heat Recovery Targeting Assessment 1549.1 Introduction, 1549.2 Data Extraction, 1559.3 Composite Curves, 1569.4 Basic Concepts, 1599.5 Energy Targeting, 1609.6 Pinch Golden Rules, 1609.7 Cost Targeting: Determine Optimal DTmin, 1629.8 Case Study, 1659.9 Avoid Suboptimal Solutions, 1699.10 Integrated Cost Targeting and Process Design, 1719.11 Challenges for Applying the Systematic Design Approach, 17210 Process Heat Recovery Modification Assessment 17510.1 Introduction, 17510.2 Network Pinch—The Bottleneck of Existing Heat Recovery System, 17610.3 Identification of Modifications, 17910.4 Automated Network Pinch Retrofit Approach, 18110.5 Case Studies for Applying the Network Pinch Retrofit Approach, 18311 Process Integration Opportunity Assessment 19511.1 Introduction, 19511.2 Definition of Process Integration, 19611.3 Plus and Minus (+/-) Principle, 19811.4 Grand Composite Curves, 19911.5 Appropriate Placement Principle for Process Changes, 20011.6 Examples of Process Changes, 205PART 3 PROCESS SYSTEM ASSESSMENT AND OPTIMIZATION 22512 Distillation Operating Window 22712.1 Introduction, 22712.2 What is Distillation?, 22812.3 Distillation Efficiency, 22912.4 Definition of Feasible Operating Window, 23212.5 Understanding Operating Window, 23212.6 Typical Capacity Limits, 25312.7 Effects of Design Parameters, 25512.8 Design Checklist, 25712.9 Example Calculations for Developing Operating Window, 25712.10 Concluding Remarks, 27613 Distillation System Assessment 28113.1 Introduction, 28113.2 Define a Base Case, 28113.3 Calculations for Missing and Incomplete Data, 28413.4 Building Process Simulation, 28713.5 Heat and Material Balance Assessment, 28813.6 Tower Efficiency Assessment, 29213.7 Operating Profile Assessment, 29513.8 Tower Rating Assessment, 29813.9 Column Heat Integration Assessment, 30013.10 Guidelines for Reuse of an Existing Tower, 30214 Distillation System Optimization 30514.1 Introduction, 30514.2 Tower Optimization Basics, 30614.3 Energy Optimization for Distillation System, 31214.4 Overall Process Optimization, 31814.5 Concluding Remarks, 326PART 4 UTILITY SYSTEM ASSESSMENT AND OPTIMIZATION 32715 Modeling of Steam and Power System 32915.1 Introduction, 32915.2 Boiler, 33015.3 Deaerator, 33315.4 Steam Turbine, 33415.5 Gas Turbine, 33815.6 Letdown Valve, 33915.7 Steam Desuperheater, 34115.8 Steam Flash Drum, 34215.9 Steam Trap, 34215.10 Steam Distribution Losses, 34416 Establishing Steam Balances 34516.1 Introduction, 34516.2 Guidelines for Generating Steam Balance, 34616.3 AWorking Example for Generating Steam Balance, 34716.4 A Practical Example for Generating Steam Balance, 35716.5 Verify Steam Balance, 36216.6 Concluding Remarks, 36417 Determining True Steam Prices 36617.1 Introduction, 36617.2 The Cost of Steam Generation from Boiler, 36717.3 Enthalpy-Based Steam Pricing, 37117.4 Work-Based Steam Pricing, 37217.5 Fuel Equivalent-Based Steam Pricing, 37317.6 Cost-Based Steam Pricing, 37617.7 Comparison of Different Steam Pricing Methods, 37717.8 Marginal Steam Pricing, 37917.9 Effects of Condensate Recovery on Steam Cost, 38417.10 Concluding Remarks, 38418 Benchmarking Steam System Performance 38618.1 Introduction, 38618.2 Benchmark Steam Cost: Minimize Generation Cost, 38718.3 Benchmark Steam and Condensate Losses, 38918.4 Benchmark Process Steam Usage and Energy Cost Allocation, 39418.5 Benchmarking Steam System Operation, 39618.6 Benchmarking Steam System Efficiency, 39719 Steam and Power Optimization 40319.1 Introduction, 40319.2 Optimizing Steam Header Pressure, 40419.3 Optimizing Steam Equipment Loadings, 40519.4 Optimizing On-Site Power Generation Versus Power Import, 40719.5 Minimizing Steam Letdowns and Venting, 41219.6 Optimizing Steam System Configuration, 41319.7 Developing Steam System Optimization Model, 417PART 5 RETROFIT PROJECT EVALUATION AND IMPLEMENTATION 42320 Determine the True Benefit from the OSBL Context 42520.1 Introduction, 42520.2 Energy Improvement Options Under Evaluation, 42620.3 A Method for Evaluating Energy Improvement Options, 42920.4 Feasibility Assessment and Make Decisions for Implementation, 44221 Determine the True Benefit from Process Variations 44721.1 Introduction, 44721.2 Collect Online Data for the Whole Operation Cycle, 44821.3 Normal Distribution and Monte Carlo Simulation, 44921.4 Basic Statistics Summary for Normal Distribution, 45622 Revamp Feasibility Assessment 45922.1 Introduction, 45922.2 Scope and Stages of Feasibility Assessment, 46022.3 Feasibility Assessment Methodology, 46222.4 Get the Project Basis and Data Right in the Very Beginning, 46522.5 Get Project Economics Right, 46622.6 Do Not Forget OSBL Costs, 47022.7 Squeeze Capacity Out of Design Margin, 47122.8 Identify and Relax Plant Constraints, 47222.9 Interactions Between Process Conditions, Yields, and Equipment, 47322.10 Do Not Get Misled by False Balances, 47422.11 Prepare for Fuel Gas Long, 47522.12 Two Retrofit Cases for Shifting Bottlenecks, 47722.13 Concluding Remarks, 48023 Create an Optimization Culture with Measurable Results 48123.1 Introduction, 48123.2 Site-Wide Energy Optimization Strategy, 48223.3 Case Study of the Site-Wide Energy Optimization Strategy, 48723.4 Establishing Energy Management System, 49223.5 Energy Operation Management, 49623.6 Energy Project Management, 49923.7 An Overall Work Process from Idea Discovery to Implementation, 500References, 502INDEX 503