Abstract: Abstract:In a power plant, the reductive allvolatile treatment mode was adopted to treat the feedwater for the 660MW supercritical unit. The method has some disadvantages, such as higher scaling rate on the boiler heating surface and shorter chemical cleaning period of the boiler. In order to solve above problems, the experiment of feed water oxygen treatment for the unit was carried out. The experiment result shows that after oxygen treatment, the iron content of the watersteam system reduced obviously. In the feed water in inlet of the economizer, the iron content reduced from 8.0～13.5μg/L to below 1.0μg/L, the ammonia addition to the feed water reduced by 60%, the operation period of the precision treatment mixed bed lengthened by 2 to 3 times, and expected treated water quantity may be above 200000 tons in a period. The acid and alkali consumption for resin regeneration and selfused water in precision treatment mixed bed were reduced, and the discharge of waste regeneration liquid was reduced, which is useful for environment protection.

Key words: Keywords:supercritical unit, reductive all volatile treatment mode, feedwater oxygen treatment, precision treatment mixed bed