Instrumentation for Monitoring and Control of Cycle Chemistry for the Steam-Water Circuits of Fossil-Fired and Combined Cycle Power Plants

摘要

A guidance document on the instrumentation for monitoring and control of cycle chemistry for the steam-water circuits of fossil-fired and combined cycle power plants was developed within the lAPWS Power Cycle Chemistry Working Group. This technical guidance document was first issued in 2009. In response to comments received, the 2012 revision includes a small number of minor updates and clarifications. These do not constitute significant changes to the scope of the document or to the guidance contained in it. This technical guidance document was authorized by the International Association for the Properties of Water and Steam (lAPWS) at its meeting in Boulder, Colorado, USA, 30 September to 5 October, 2012, for issue by its Secretariat. The members of the lAPWS are: Britain and Ireland, Canada, the Czech Republic, Germany, Japan, Russia, Scandinavia (Denmark, Finland, Norway, Sweden), and the United States of America. Associate Members are Argentina and Brazil, Australia, France, Greece, Italy, New Zealand, and Switzerland. The document represents the accumulated experience of the lAPWS Power Cycle Chemistry (PCC) Working Group with representation from 15 countries. In order to achieve suitable chemical conditions in steam-water circuits it is essential to establish reliable monitoring of key parameters on every plant. This enables the demonstration of operation within cycle chemistry targets, and alerts the operators to the need to take corrective action when the target conditions are compromised. This technical guidance document considers conventional fossil and combined cycle/HRSG plants and identifies the key instrumentation and monitoring techniques required for each plant type and cycle chemistry treatment. It is emphasized that this is an lAPWS guidance document and that, depending on local requirements, the use of simpler instrumentation may be adequate, whereas more complex techniques and instrumentation may be necessary when specific issues arise.