CIBO ENERGY EFFICIENCY HANDBOOK COUNCIL OF INDUSTRIAL BOILER OWNERS (CIBO) 6035 BURKE CENTRE PARKWAY, SUITE 360 BURKE, VA 22015 EDITED BY RONALD A. ZEITZ Notice of Disclaimer This Energy Efficiency Handbook has been prepared by the Council of Industrial Boiler Owners (CIBO). Neither CIBO nor any of its members, nor any person acting on behalf of them, make any representation or warranty whatsoever, whether express or implied, or assume any legal liability, regarding the completeness or accuracy of the information contained herein, with respect to the use of any information, apparatus, method, process, or similar item disclosed in this handbook, including merchantability and fitness for a particular purpose; or that any such use does not infringe on or inter­ fere with privately owned rights, including any party’s intellectual property. Furthermore, neither CIBO nor any of its members, nor any person acting on behalf of them, assume any responsibility resulting from any person’s selection or use of this re- port or of any information, apparatus, method, process, or similar item described in this report. Reference to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorse­ ment, recommendation, or favoring. The views and opinions of the authors expressed herein do not necessarily state or reflect those of the United States Government, any state government, or any federal or state agency thereof. Any person wishing to use the information, technologies, or procedures described herein should consult with a quali­ fied expert to ascertain their fitness for the intended use. November 1997 Copyright 1997 Council of Industrial Boiler Owners All rights reserved. The reproduction of this work in any form whether by copying in printed or machine format, including xerography, photocopy, sound recording, or ma- chine readable format, and in any information storage and/or retrieval system is strictly prohibited without the prior written approval of the publisher. ii Council of Industrial Boiler Owners Table of Contents List of Figures and Tables: ............................................................... v Acknowledgments ......................................................................vii Chapter 1: Introduction .............................................................. 1 Chapter 2: Water Treatment .......................................................... 3 Boiler Water Problems ........................................................ 3 Deposit-Related Problems ..................................................... 3 Corrosion-Related Problems ................................................... 5 Boiler Water Treatment ....................................................... 7 Benefits From a Proper Water Treatment Program .......................... 11 Operator’s Checklist for Water Treatment Systems Maintenance ............ 11 Chapter 3: Combustion .............................................................. 13 Air Infiltration ............................................................... 13 Combustion Air Temperature ............................................... 13 Fuel and Air Linkages ....................................................... 14 Types of Combustion Systems and Their Particular Requirements ........... 14 Operator’s Checklist for Combustion Systems Efficiency and Maintenance ... 18 Chapter 4: Boilers ................................................................... 19 Boiler Efficiency ............................................................. 19 Conservation of Energy ...................................................... 19 Heat Loss Sources ........................................................... 19 Turbulators and Firetube Boilers ............................................ 21 Operator’s Checklist for Efficient Boiler Operation and Maintenance ....... 21 Chapter 5: Controls .................................................................. 25 Burner Controls ............................................................. 25 Supervisory Monitoring and Control Strategies .............................. 29 Chapter 6: Heat Recovery ............................................................ 33 Economizers ................................................................. 33 Air Heaters .................................................................. 33 Other Sources of Heat Recovery ............................................. 34 Energy Efficiency Handbook iii Chapter 7: Auxiliaries ............................................................... 35 Fans ......................................................................... 35 Boiler Feedwater Pumps ..................................................... 35 Motors and Turbines ........................................................ 36 Electronic Motor Drives ..................................................... 36 Materials Handling Equipment .............................................. 37 Boiler Sootblowers .......................................................... 37 Cogeneration ................................................................ 38 Sale of Excess Electricity ..................................................... 39 Chapter 8: Energy Auditing .......................................................... 41 Steam Systems ............................................................... 41 Steam Utilization ............................................................ 41 Cooling Towers ............................................................. 41 Compressed Air ............................................................. 42 Fans ......................................................................... 42 Pumps ....................................................................... 42 Chapter 9: Flue Gas Treatment ...................................................... 43 NOx Reduction Techniques ................................................. 43 Solid Particle Removal ....................................................... 44 Chapter 10: Steam Systems ............................................................ 47 General Operational Procedures ............................................ 47 Steam Traps ................................................................. 48 Insulation ................................................................... 48 Leaks ........................................................................ 49 Pressure ..................................................................... 49 Chapter 11: Compressed Air Systems and Diesel Engine Power Cogeneration .......... 51 Operator’s Checklist for Compressed Air Systems ........................... 52 Diesel Engine Power Cogeneration .......................................... 52 Chapter 12: Electrical Distribution Systems ........................................... 55 Monitoring and Metering Techniques ....................................... 56 Chapter 13: Cooling Systems .......................................................... 57 Cooling Tower Inspection Process ........................................... 57 Energy Efficiency in Cooling Tower Operations ............................. 58 Appendix A: Excess Air Levels ......................................................... 59 Appendix B: Savings Possible through Heat Recovery on Continuous Blowdown and Improved Blowdown Control ......................................... 61 Appendix C: References ............................................................... 63 iv Council of Industrial Boiler Owners List of Figures and Tables Figures: 2-1 Effects of boiler scale on tube metal temperature ................................... 4 2-2 Effect of CaSO4 scale on high heat flux boiler plate ................................ 5 2-3 Clarifier ............................................................................ 7 2-4 Two-bed demineralizer ............................................................ 8 2-5 Deaerator .......................................................................... 8 3-1 Underfeed stoker ................................................................ 16 3-2 Spreader stoker .................................................................. 17 3-3 Mass-feed stoker ................................................................. 17 4-1 Heat loss sources in a stoker boiler ............................................... 19 4-2 Operator’s log for twice-daily readings ........................................... 22 4-3 Operator’s log for hourly readings ............................................... 22 5-1 Typical computer-monitored metered combustion control system ................ 26 5-2 Carbon monoxide content compared to a preset point ........................... 27 5-3 Relationship between boiler efficiency, steam cost, and incremental steam cost ... 31 7-1 Static pressure rise and power versus air flow .................................... 38 7-2 Industrial steam-electric cogeneration, system thermal efficiency 80 to 90% ...... 38 7-3 Industrial combination turbine combined cycle cogeneration, system thermal efficiency 80 to 90% .............................................................. 39 7-4 Generation and cogeneration operation and benefits comparisons ............... 39 11-1 An ebullient system .............................................................. 53 12-1 Electrical power distribution system .............................................. 55 B-1 The production of flash steam from