هزینه‌ها و مزایای اتوماسیون کامل تصفیه‌خانه آب: گزارش AwwaRF 91213

Water utilities are facing a number of trends that are having a broad impact on operations, maintenance, and capital expenditures including increasing labor, energy, and chemical costs. Advanced automation is viewed as a tool that can help to minimize the impacts of many of these. Complete automation of water treatment plants, where the facilities run unattended for some period of time, is used by many utilities as a cost savings strategy. However, many utilities have not implemented complete automation yet for a variety of reasons. An economic assessment methodology for automation projects would be useful to utility decision makers. The objectives of the project were to (1) identify costs, benefits, and risks associated with complete water treatment plant (WTP) plant automation; (2) identify the levels of automation needed for unattended operation; (3) review regulatory requirements related to unattended operation; (4) develop an economic analysis method useful to utility decisions makers for evaluating the life-cycle cost/benefits of automation investments; and (5) develop automation case studies demonstrating the approach. The study included questionnaires, a review of literature and applicable regulations, an evaluation of current economic analysis techniques, industry best practices, and case studies. A water utility focus group provided guidance during the project. The intent of this project was not to perform a statistically representative survey of the water industry regarding this topic, but to provide several utility automation experiences for consideration. To that end, six automation case studies were completed and are documented in the report. This report includes information on the current levels of automation available, other industry experience, and cost information; utility case studies and sample economic calculations to enhance understanding the issues and concepts; and tools that will allow a tailored analysis to the unique utility automation situations. The authors believe that the report provides a unique and comprehensive source of information, methodologies, and examples for use by decision makers involved in the evaluation and planning of water treatment plant automation projects, specifically, automation projects that facilitate unattended operations. The report provides information not only on the technical aspects of automation but also from a business perspective. Efficient and Customer Responsive Organization: Utility Management Tools TITLE PAGE 5 DISCLAIMER - COPYRIGHT 6 TABLE OF CONTENTS 7 LIST OF TABLES 11 LIST OF FIGURES 13 FOREWORD 15 ACKNOWLEDGMENTS 17 EXECUTIVE SUMMARY 19 CHAPTER 1: INTRODUCTION AND BACKGROUND 25 Introduction 25 Objectives 25 Report Organization 25 Chapter 1 – Introduction and Background 25 Chapter 2 – WTP Automation Regulations and Industry Practices 25 Chapter 3 – Costs and Benefits of WTP Automation Systems 26 Chapter 4 – Automation Considerations 26 Chapter 5 – WTP Unit Process Considerations 26 Chapter 6 – “Balanced Approach” Methodology 26 Appendix A – NPV Examples 26 Appendix B - Case Studies 26 Appendix C – Cost Database and Example Cost Estimate 27 Appendix D – Literature Review and Search 27 Drivers of Unattended Plant Operations 27 Regulations and Unattended Plant Operation 27 Drivers of Economic Analysis 28 Understanding the Costs and Benefits 29 Tangible Costs 29 Economic Life Cycle Cost Analysis 31 Strategic Costs and Benefits 32 Balanced Scorecard 32 Asset Management 33 Literature Review 33 Technology Trends 34 Automation Planning, Design, Procurement, and Implementation 34 Water Treatment Process Optimization 34 Energy Management 35 Cost-Benefit Analysis 35 Water Industry Regulations 36 Non-Water Industry Automation 36 Significance of the Project 37 Summary 38 CHAPTER 2: WTP MONITORING AND CONTROL REGULATIONS AND INDUSTRY PRACTICES 39 Overview 39 State and Federal Regulations Governing Operational Monitoring of Water Treatment Plants 39 Regulations Governing Plant Staffing and Unattended Operation 41 Federal Regulations 41 State Regulations 41 Classification of CWS 41 Staffing Requirements 42 Industry Practice 43 CHAPTER 3: COST AND BENEFIT CONSIDERATIONS OF AUTOMATION SYSTEMS 45 Introduction 45 Quantifying the Costs and Benefits 45 Water Treatment Plant Automation Systems 45 Process Monitoring and Control 47 Process Automation 47 Plant-wide SCADA 47 Remote Monitoring 47 Cost and Benefit Categories 48 Tangible Costs 48 Intangible Costs 48 Tangible Benefits 48 Intangible Benefits 48 Control System Project Phases 48 Procurement Approaches 49 Automation Cost Estimating 49 Planning 49 Design 50 Bid Services 52 Construction Phase Support 52 Contracting Method Best Practices 52 Implementation Costs 53 Generic Implementation Cost Model 53 Automation Package Spreadsheets 54 Component Cost Estimate Database 55 Direct Costs 55 Indirect Costs 56 Implementation Cost Estimating 57 Additional Factors Affecting Cost 58 Market Conditions 58 Working Conditions 58 Automation Requirements 59 Procurement Methods 59 Reliability and Expected Life 59 Post-Acceptance Costs 60 Maintenance Costs 60 Spare Parts Inventory 62 Total Project Cost 62 Estimating the Benefits 62 Life-Cycle Cost Best Practices 63 Summary 63 CHAPTER 4: AUTOMATION CONSIDERATIONS 65 Water Treatment Plant Automation Components 65 Risk and Failure Analysis 65 Risk, Reliability and Failures 66 Automation Design Reliability Considerations 67 Electrical Power 68 Hardware 68 Communications Network 68 Local Control Panels 69 Master Control Computers 69 Software Considerations 69 Operating Systems 69 Application Software 70 Configuration Files 70 Data Considerations 70 Accuracy 70 Timeliness and Availability 71 Data Security 71 Treatment Plant Reliability Considerations 71 Risks Analysis and Mitigation Measures 72 Risk Analysis Approach 72 Probability of Failure 72 Consequences of Failure 73 Risk Evaluation 73 Identify and Develop Alternatives 75 Barriers to Unattended Operations 75 Recommendation Summary 76 CHAPTER 5: UNATTENDED WTP PROCESS SPECIFIC CONSIDERATIONS 79 General Considerations 79 Plant Operation and Maintenance Costs 79 Plant Types and Processes 83 Representative WTP Processes 84 Raw Water Pumping 84 Coagulation/Flocculation/Sedimentation 88 Dual/Multimedia Filtration 95 Chlorine Disinfection 99 Finished Water Pumping 103 Additional Energy Considerations 106 Energy Rates 106 Energy Charges 106 Demand Charges 107 Monitoring Your Energy Use 109 Considering VFDs for Control 109 Financing Opportunities 110 Summary 110 CHAPTER 6: ASSESSMENT METHODOLOGIES 113 Introduction 113 Methodology Overview 113 Methodology Steps 114 Step 1 – Research and Define the Project 114 Step 2 – Brainstorm and Document Benefits 119 Step 3 - Analyze Financial Benefits 122 Step 4 – Develop Project Costs 123 Step 5 – Calculate Project NPV 124 Develop the Business Case Document 125 Business Case Outline 126 Summary and Recommendations 126 Future Research 127 APPENDIX A: EXAMPLE BUSINESS CASE ANALYSIS 129 APPENDIX B: CASE STUDIES 147 APPENDIX C: COST DATABASE AND EXAMPLE COST ESTIMATE 173 APPENDIX D: LITERATURE RESEARCH AND REVIEW 193 REFERENCES 223 ABBREVIATIONS 233 Planning,Management,Information Management,Planning,Capital Improvement Planning,Information Technology,AwwaRF