Application Note: Determination of Trace Anions in Nuclear Power Plant Secondary Feed Water Containing Polyacrylic Acid
7 June 2013
In 2011, nuclear power plants (NPPs) provided 12.3% of the world’s electricity production. In the U.S., pressurized water reactors (PWRs) comprise approximately two-thirds of the NPPs. The PWR consists of a primary reactor system and a secondary steam system. The chemistry of the feed water must be strictly controlled in both the primary and secondary systems. To protect the secondary steam system from corrosion, an amine such as ethanolamine (ETA) is added to the feed water to obtain an alkaline pH,4 while a volatile oxygen scavenger such as hydrazine is used to ensure a reducing environment to form protective magnetite on the surfaces of the steam generator. Since 2009, polyacrylic acid (PAA) has been used at several NPPs as a dispersant in the secondary system to inhibit corrosion on the boiler surfaces. In this application note read how ion chromatography is used to detect ionic impurities in order to prevent corrosive conditions.