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Chemical Process Dynamics and Controls Book I (Chapters 1-9)

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Chemical Process Dynamics and Controls Book I (Chapters 1-9) Chemical Process Dynamics and Controls Book I (Chapters 1-9) Welcome to the University of Michigan Chemical Engineering Process Dynamics and Controls Open Textbook. This electronic textbook is a student-contributed open-source text covering the materials used at Michigan in our senior level controls course. Follow this link to find more information about this course. If you would like to suggest changes to these pages, please email [email protected] . Click here for the 2007 version and here for the 2006 version of the text. Content is available under Creative Commons Attribution 3.0 Unported License. Table of Contents Part I Process Control Introduction.................................................................................. 1 Chapter 1. Overview......................................................................................................................... 3 Section 1. Introduction to Controls: Background and design methodology ......................... 3 1.1 Introduction ...........................................................................................................................................................3 1.2 Process Control Background...........................................................................................................................3 1.3 The Objectives of Control .................................................................................................................................4 1.4 Definitions and Terminology..........................................................................................................................5 1.5 Design Methodology for Process Control..................................................................................................6 1.6 References...............................................................................................................................................................8 Section 2. Introduction to DCS: Control system hardware ........................................................... 9 2.1 Introduction ...........................................................................................................................................................9 Section 3. Current Significance: Process controls and you .........................................................10 3.1 Introduction ........................................................................................................................................................ 10 3.2 Automation.......................................................................................................................................................... 10 Section 4. Failures in Process Control: Bhopal, Three Mile Island ..........................................11 4.1 Bhopal, India Disaster..................................................................................................................................... 11 4.1.1 Overview ..................................................................................................................................................... 11 4.1.2 Results.......................................................................................................................................................... 12 4.1.3 Reference .................................................................................................................................................... 12 4.2 Three Mile Island Disaster............................................................................................................................ 12 4.2.1 Overview ..................................................................................................................................................... 12 4.2.2 Results.......................................................................................................................................................... 13 4.2.3 Reference .................................................................................................................................................... 14 4.3 Texas City Disaster........................................................................................................................................... 14 4.3.1 Overview ..................................................................................................................................................... 14 4.3.2 Results.......................................................................................................................................................... 15 4.3.3 Reference .................................................................................................................................................... 15 Section 5. Process Controls in Everyday Life: Applying process control thinking to everyday situations......................................................................................................................................16 5.1 Introduction ........................................................................................................................................................ 16 5.2 Examples of Process Control for the Common Man........................................................................... 16 5.2.1 Consumption ............................................................................................................................................. 16 5.2.2 Hygiene........................................................................................................................................................ 17 Chapter 2. Modeling Basics..........................................................................................................19 Section 1. Verbal Modeling: process description, control specifications, and connections......................................................................................................................................................19 1.1 Introduction ........................................................................................................................................................ 19 1.2 Prerequisite Information Regarding a Process.................................................................................... 19 1.3 Step‐by‐Step Method For Describing Controls and Their Purpose............................................. 21 1.4 Alternative Method of Verbal Modeling.................................................................................................. 25 1.5 The Barkel Method of Verbal Modeling .................................................................................................. 27 1.6 Common Errors ................................................................................................................................................. 30 1.7 Worked out Example 1................................................................................................................................... 30 1.8 Worked out Example 2................................................................................................................................... 33 1.9 Sage's Corner ...................................................................................................................................................... 36 1.10 References......................................................................................................................................................... 37 Section 2. Degrees of Freedom: importance, calculation procedure, and examples .......38 2.1 Introduction ........................................................................................................................................................ 38 2.2 Definition.............................................................................................................................................................. 38 2.3 The Process.......................................................................................................................................................... 38 2.4 Applications......................................................................................................................................................... 39 2.5 Example 1: Blender.......................................................................................................................................... 39 2.6 References............................................................................................................................................................ 40 Section 3. Incidence Graphs: interpretations, consistency, and inconsistency..................41 3.1 Introduction ........................................................................................................................................................ 41 3.2 Monotonicity....................................................................................................................................................... 42 3.3 Incidence Graphs............................................................................................................................................... 44 3.3.1 Traversing .................................................................................................................................................. 45 3.4 Consistent, Inconsistent, and Partially Consistent ............................................................................
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