A guidance document on volatile treatments for the steam-water circuits of fossil and combined cycle/HRSG power plants was developed within the IAPWS Power Cycle Chemistry Working Group. This technical guidance document has been authorized by the International Association for the Properties of Water and Steam (IAPWS) at its meeting in Niagara Falls, Canada, 18–23 July 2010, for issue by its Secretariat. The members of IAPWS are: Britain and Ireland, Canada, the Czech Republic, Denmark, France, Germany, Greece, Japan, Russia, and the United States of America; associate members are Argentina and Brazil, Italy, and Switzerland.

In order to control corrosion throughout the steam/water circuits of fossil and combined cycle/HRSG plants, it is essential for the operator of the plant to choose and optimize a chemical treatment scheme that is customized to that plant. Normal target values for the appropriate level of instrumentation around the cycle must be chosen. This technical guidance document considers fossil and combined cycle/HRSG plants and identifies the normal target values for each plant type when operating with a volatile treatment. It is emphasized that this is an IAPWS guidance document and that, depending on local requirements, the normal or target values will need to be customized for each plant depending on the actual conditions of operation, the equipment and materials installed, and the condenser cooling media.

This paper discusses the cycle chemistry improvement program being undertaken at Eraring Power Station in the state of New South Wales, Australia. This program commenced in 2007 following an external benchmarking audit that found the cycle chemistry performance was low compared with other worldwide organisations. The aim of the program is to achieve the best practice in cycle chemistry within the limitations of the plant. Details are given on why this improvement program was necessary, what problems were discovered by plant investigations, how change is being achieved, and what is planned for the future.

In June this year, the 30th Annual University of Illinois Electric Utility Chemistry Workshop took place in Champaign, IL, U.S.A. The content of the workshop and abstracts of the papers presented at this event are compiled in this paper.

The surveillance of wall thinning effects caused by flow-induced degradation in piping and vessels is one of the key issues for the safe operation of thermal power plants, as wall thinning may cause spontaneously occurring component failures. For the safe identification of system areas which are sensitive to wall thinning, a comprehensive plant-wide strategy needs to be applied, considering the effects and superposition of different degradation modes. Flow-induced corrosion (FIC), e.g., flow-accelerated corrosion (FAC), liquid droplet impingement corrosion (LDI) and cavitation corrosion is a degradation process resulting in wall thinning of piping, vessels, heat exchanger and further equipment made of carbon and low-alloy steel. The FIC degradation mechanism occurs only locally under specific condition of flow, water chemistry, temperature and materials applied.
In some cases combined effects can occur. These are for single-phase flow conditions FAC and cavitation corrosion or for two-phase flow conditions, the combined occurrence of FAC and LDI.
Within the scope of this paper two examples will be given for the identification and detailed evaluation of a sub-system affected by the superposition of FAC with cavitation erosion and LDI.

Much has been presented about analytical instrumentation, its use in making on-line measurements, and plant control based on the results. This presented a summary of practical recommendations for achieving good results and verifying them for parameters of conductivity, pH, ORP and dissolved oxygen. The old saying GIGO (garbage in: garbage out) certainly applies to analytical measurements. Means to assure quality of the input to improve the reliability and accuracy of the output were provided.