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Dynamic Simulation for the Qatar Pertroleum Propane and Butane Storage Facilities
김영배(STEP Engineering & Consulting 대표, 약력)
I. 공정설명
Up-stream으로 생산된 Propane 및 Butane은 각각 500㎥/hr 유량으로 Run-down 되어 Tank Terminal로 이송된다. Run-down 된 Propane 및 Butane은 각각 -45˚C 및 -1˚C이다. 각 저장 탱크는 온도의 변화 및 기후조건에 따라 Boil Off되는 Bog Propane 및 Bog Butane을 Centrifugal Compressor로 압축하여 Condenser로 보내서, C4refrigerator 이용하여 Condensing하여 저장 Tank로 회수하여 저장한다. Propane Bog Compressor는 Centrifugal Type이며 Maximum Load때는 2대가 운전되며 1대는 Stand-by이며, Model은 동일 하다. Butane Bog Compressor는 Centrifugal Type이며 Maximum Load때는 2대가 운전되며 1대는 Stand-by이며 ,model은 3대가 서로 다르다. 대기온도는 10˚C~52˚C이다. 저장탱크는 Dome Roof Type이며 운전 압력은 0Kg/㎠G이며, 운전온도는 Propane Tank는 -45˚C이며 Bytane Tank은 0˚C이다.
저장 탱크는 각각 4대로 운전된다. 또한 저장된 Propane 및 Butane은 수출 부두로 Loading Pump 의해 4000㎥/hr로 LPG Tanker에 이송된다.
기존공장의 냉동기가 고장 시 Run-down된 Propane Cooling되지 않고 40˚C로 이송 되었을 때 저장 탱크에서 BOIL OFF 량.
저장탱크에서 기후변화와 운전MODE 변화에 따른 각 탱크에서 BOIL -OFF GAS량에 따른 CASE STUDY.
PRopane Refrigerator의 Settle Out Pressure 및 Settle Out Pressure에서 Compressor의 Start-up시 각 운전인자에 대한 고찰.
II. 강의 목적
위 공정을 Dynamic Simulation을 할 경우,
필요 자료
준비 자료
DYNAMIC SIMULATION을 위한 절차 및 방법을 Dynamic Simulator은 HYSIS을 기준으로 설명하고자 한다.
III. Contents
-
공정설명 (PDF, 261 KB, 8 pages)
- Introduction
- Operating Philosophy For Propane System
- 각 UNIT OPERATION에 대한 고찰 (PDF, 713 KB, 14 pages)
- SYSTEM DERSIGN BASIS ((PDF, 169 KB, 3 pages)
-
UNIT OPERATION ((PDF, 115 KB, 2 pages)
- Tank
- Pump
- Compressor
- Safety Facilities
-
DYNAMIC MODEL DATA (PDF, 288 KB, 10 pages)
- Unit Operation Summary
- Dynamic Model Details
-
DYNAMIC SIMULATION (PDF, 846 KB, 51 pages)
- Dynaic Simulation Case
- Simulation PFD
- Settle Out Pressure
- Start-up Duty Compressor From Settle Out Pressure
- Load Transfer from Duty to Stand-by Compressor
- Case Studites for Each Load Changes
- Case Study for All Possible Changes
- Load Transfer at Each Cases
- Settle Out Case With Liquid Filled Surge Drum
-
SUMMARY AND RESULTS (PDF, 222 KB, 3 pages)
- Settle Out Pressure Results
- Start-up Results from Settle Out Conditions
- Load Transfer Results
- Case Study Results
모델예측제어 특별강좌
I. Overview of Process Control
Full-TEXT(PDF, 939 KB, 80 pages)
PDFs(page): 1-12 | 13-19 | 20-28 | 29-40 | 41-49 | 50-63 | 64-73 | 74-80
1. Basic Low-Level Control / 4 1.1 Basic Idea of Feedback/Feedforward Control / 4 1.2 Motivation- Why(negative) Feedback Control? / 9 1.3 Elements of a Feedback System / 13 1.4 Pid Formulations / 20 1.4.1 Integral(I) Control / 20 1.4.2 Proportional(P) Control / 21 1.4.3 Proportional Integral(PI) Control / 24 1.4.4 Proportional Integral Derivative(PID) Control / 25 1.4.5 Digital Implementation / 27 1.5 Quantitive PID Tuning Methods / 29 1.5.1 Continuous Cycling Method / 29 1.5.2 Reaction-curve-based Method / 38 1.5.3 Fopdt-based Tuning Rules / 41 1.5.4 Direct Synthesis Method - IMC Tuning / 46 1.6 Practical Considerations / 50 2. Multi-loop Control and Further Practical Issues / 55 2.1 Feedforward-feedback Control / 55 2.2 Cascade Control / 57 2.3 Override Control / 61 3. Control of Multi-input Multi-output(MIMO) Processes / 62 3.1 MIMO Process? / 62 3.2 Interaction and I/O Pairing / 64 3.2.1 Interaction / 64 3.2.2. I/O Pairing / 67 3.3 Decoupling / 70 3.4 Current Trends / 74 3.4.1 Computer Integrated Process Management / 74 3.4.2 Model-based Approaches / 75 3.4.3 Computing Environment / 77 3.4.4 Computer Control System / 78 3.4.5 Smart Instrument and Field Bus / 79
II. Overview of Industrial MPC Techniques
Full-TEXT(PDF, 1,112 KB, 141 pages)
PDFs(page): 1-8 | 9-24 | 25-34 | 35-49 | 50-56 | 57-67 | 68-84 | 85-97 | 98-106 | 107-119 | 120-126 | 127-131 | 132-141
1. Introduction To Model Predictive Control / 5 1.1 Background for MPC Development / 5 1.2 What's MPC? / 6 1.3 Why MPC? / 8 1.3.1 Some Examples / 9 1.3.2 Summary / 24 1.4 Industrial Use of MPC: Overview / 25 1.4.1 Motivation / 25 1.4.2 Survey of MPC Use / 31 1.5 Historical Perspective / 32 1.6 Challenges / 34 1.6.1 Modeling & Identification / 34 1.6.2 Incorporation of Statistical Concepts / 41 1.6.3 Nonlinear Control / 48 1.6.4 Other Issues / 49 2. Dynamic Matrix Control / 50 2.1 Finite Impulse and Step Response Model / 50 2.1.1 Overview of Computer Control / 50 2.1.2 Impulse Response and Impulse Response Model / 52 2.1.3 Step Response and Step Response Model / 54 2.2 Multi-step Prediction / 57 2.2.1 Overview / 57 2.2.2 Recursive Multi-step Prediction for an Fir System / 58 2.2.3 Recursive Multi-step Prediction for an Fir System with Differenced Input / 62 2.2.4 Multivariable Generation / 66 2.3 Dynamic Matrix Control Algorithm / 67 2.3.1 Major Constituents / 67 2.3.2 Basic Problem Setup / 68 2.3.3 Definition and Update of Memory / 69 2.3.4 Prediction Equation / 70 2.3.5 Quadratic Criterion / 73 2.3.6 Constraints / 75 2.3.7 Quadratic Programming / 79 2.3.8 Summary of Real-time Implementation / 83 2.4 Additional Issues / 84 2.4.1 Feasibility Issue and Constraint Relaxation / 84 2.4.2 Guidelines for Choosing the Horizon Size / 85 2.4.3 Bi-level Formulation / 86 2.4.4 Property Estimation / 89 2.4.5 System Decomposition / 91 2.4.6 Model Conditioning / 98 2.4.7 Blocking / 102 3. System Identification / 107 3.1 Dynamic Matrix Identification / 107 3.1.1 Step Testing / 107 3.1.2 Pulse Testing / 111 3.1.3 Random Input Testing / 112 3.1.4 Data Pretreatment / 118 3.2 Basic Concepts of Identification / 120 3.3 Model Description / 124 3.3.1 Nonparametric Model / 124 3.3.2 Parametric Method / 125 3.4 Experimental Conditions / 128 3.4.1 Sampling Interval / 128 3.4.2 Open-loop Vs. Closed-loop Experiments / 129 3.4.3 Input Design / 130 3.5 Identification Methods / 132 3.5.1 Prediction Error Method / 132 3.5.2 Subspace Identification / 137 3.6 Identification of a Process with Strong Directionality / 138
III. Background for Advanced Issues
Full-TEXT (PDF, 1,112 KB, 165 pages)
PDFs(page): 1-10 | 11-22 | 23-29 | 30-40 | 41-51 | 52-58 | 59-66 | 67-78 | 79-91 | 92-101 | 102-115 | 116-126 | 127-133 | 134-143 | 144-158 | 159-165
1. Basics of Linear Algebra / 5 1.1 Vectors / 5 1.2 Matrices / 11 1.3 Singular Value Decomposition / 23 2. Basic of Linear Systems / 30 2.1 State Space Description / 30 2.2 Finite Impulse Response Model / 38 2.3 Truncated Step Response Model / 41 2.4 Reachability and Observability / 44 2.5 Static State Feedback Controller and State Estimator / 47 3. Basics of Optimization / 52 3.1 Introduction / 52 3.2 Unconstrained Optimization Problems / 55 3.3 Necessary Condition of Optimality for Constrained Optimization Problems / 59 3.4 Convex Optimization / 67 3.5 Algorithm for Constrained Optimization Problems / 71 4. Ramdom Variables / 79 4.1 Introduction / 79 4.2 Basic Probability Concepts / 81 4.2.1 Probability Distribution, Density:Scalar Case / 81 4.2.2 Probability Distribution, Density:Vector Case / 83 4.2.3 Expectation of Random Variables and Random Variable functions:Scalar Case / 86 4.2.4 Expectation of Random Variables and Random Variable functions:Vector Case / 87 4.2.5 Conditional Probability Density:Scalar Case / 92 4.2.6 Conditional Probability Density:Vector Case / 97 4.3 Statistics / 99 4.3.1 Prediction / 99 4.3.2 Sample Mean and Covariance, Probabilistic Model / 100 5. Stochastic Processes / 102 5.1 Basic Probability Concepts / 102 5.1.1 Distribution Function / 102 5.1.2 Mean and Covariance / 103 5.1.3 Stationary Stochastic Processes / 103 5.1.4 Spectra of Stationary Stochastic Processes / 104 5.1.5 Discrete-time White Noise / 106 5.1.6 Colored Noise / 106 5.1.7 Integrated White Noise and Nonstationary processes / 108 5.1.8 Stochastic Differences Equation / 109 5.2 Stochastic System Models / 111 5.2.1 State-space Model / 111 5.2.2 Input-output Models / 114 6. State Estimation / 116 6.1 Linear Observer Structure / 117 6.2 Pole Placement / 119 6.3 Kalman Filter / 120 6.3.1 Kalman Filter as the Optimal Linear Observer / 121 6.3.2 Kalman Filter as the Optimal Estimator for Gaussian Systems / 123 7. System Identification / 127 7.1 Problem Overview / 127 7.2 Parametric Identification Methods / 128 7.2.1 Model Structures / 129 7.2.2 Parameter Estimation via Prediction Error minimization / 134 7.2.3 Parameter Estimation via Statistical Methods / 143 7.2.4 Other Methods / 150 7.3 Nonparametric Identification Methods / 151 7.3.1 Frequency Response Identification / 152 7.3.2 Impulse Response Identification / 156 7.3.3 Subspace Identification / 158
IV. Advanced Issues in MPC
Full-TEXT(PDF, 559 KB, 36 pages)
PDFs(pg): 1-8 | 9-26 | 27-30 | 31-32 | 33-36
1. State-space Model Predictive Control / 3 1.1 Shortcomings of Current Industrial MPC Practice / 3 1.2 State Space MPC / 5 1.3 Disturbance Estimation via State Estimation / 7 1.4 MPC Formulation Using State-space Model / 12 2. Nonlinear and Adaptive Model Predictive Control / 13 2.1 Motivation / 13 2.2 Issues in Nonlinear MPC / 15 2.3 Linearization Based Nonlinear MPC / 17 2.4 Example: Paper Machine Headbox Control / 24 2.5 Additional Issues / 27 2.6 Recursive Parameters Estimation / 28 2.7 Adaptive MPC Formulation / 29 2.8 Example: Binary Distillation Column / 30 2.9 Potential Improvements in System Identification / 33
V. Statistical Process Monitoring and Quality Control
Full-TEXT(PDF, 442 KB, 63 pages)
PDFs(page): 1-8 | 9-15 | 16-25 | 26-38 | 39-49 | 50-60 | 61-63
1. Overview and Fundamentals of SPC / 5 1.1 Introduction / 6 1.1.1 Motivation for SPC / 6 1.1.2 Main Points / 7 1.2 Traditional SPC Techniques / 8 1.2.1 Milestones / Key Players of SPC / 8 1.2.2 Shewart Chart / 9 1.2.3 Cusum Chart / 12 1.2.4 Ewma Chart / 14 1.3 Multivariate Analysis / 15 1.3.1 Motivation / 15 1.3.2 Basics of Multivariable Statistics and Chi-square monitoring / 17 1.3.3 Principal Component Analysis / 21 1.3.4 Examples: Multivariate Analysis Vs. Single Variate analysis / 25 1.4 Time Series Modeling / 25 1.4.1 Limitations of Rhe Traditional SPC Methods / 25 1.4.2 Motivating Example / 27 1.4.3 Time-series Models / 30 1.4.4 Computation of Prediction Error / 31 1.4.5 Including the Determinstic Inputs Into the Model / 32 1.4.6 Modeling Drifting Behavior Using a Nonstationary Sequence / 33 1.4.7 Multivariable Time-series Model / 36 1.5 Regression / 38 1.5.1 Problem Definition / 38 1.5.2 The Method of Least Squares / 39 1.5.3 Limitations of Least Squares / 41 1.5.4 Principal Component Regression / 42 1.5.5 Partial Least Squares (PLS) / 44 1.5.6 Nonlinear Extentions / 46 1.5.7 Extensions to the Dynamic Case / 49 2. Application and Case Studies / 50 2.1 Pca Monitoring of an Sbr Semi-batch Reactor System / 51 2.1.1 Introduction / 51 2.1.2 Problem Description / 52 2.1.3 Results / 53 2.2 Data-based Inferential Quality Control in Batch Reactors / 61 2.2.1 Introduction / 61 2.2.2 Case Study in Details / 62 2.3 Inferential Quality Control of Continuous Pulp Digester / 63 2.3.1 Introduction / 63 2.3.2 Case Study in Details / 63