With the demand or higher efficiencies, lower maintenance and operating costs for boilwers and turbines, high-purity water treatment systems are becoming more crucial to the operation of power plants.
Modern power plants, operating at supercritical and ultra upercritical boiler pressures and temperatures, require high-purity water that approaches quality levels at the theoretical levels. High-efficiency gas-fired combustion turbines (CTs) use high-purity water for nitrogen oxide (NOx) control and sprint mode. Heat recovery steam generators (HRSGs) and once-through steam generators (OTSGs) also require high-purity water for the same reasons as boilers and steam turbines.
The versatility and efficiency of counter-current regenerated short-bed ion exchange (IX) deionizer systems produce high-purity water from feeds of variable characteristics, with lower chemicals consumption and waste volumes, and without the need for final polishing using mixed beds.
Effective pretreatment for reverse osmosis (RO) and IX deionizer systems is a crucial requirement that not only contributes to the production of highpurity water, but also helps to reduce the operating and maintenance costs of the entire system.
This article discusses the use of short bed IX deionizer systems for the production of high-purity boiler feed make-up water, and condensate polishing. The article also examines the use of micro media filtration (MMF) as a pretreatment for RO or IX systems. The experiences of several installations are outlined for applications in power generation and cogeneration plants.