Using Water Chemistry Technology to Improve the Reliability of Nuclear Power Plants

摘要

As of 1999, there were 28 BWR units and 23 PWR units operating in Japan, and light water reactors accounted for 35 percent of the country's total electric power. Since the beginning of commercial operations in 1970, however, Japan's light water reactors have experienced many corrosion problems, and a variety of countermeasures have been utilized. In the case of BWRs, nuclear-grade 316 LC stainless and new weld methods were developed to prevent recirculating pipes from cracking. Hydrogen is injected to prevent SCC of in-reactor materials. In the case of PWRs, thermally treated alloy 690 (690TT) was developed and employed to prevent IGA/SCC of steam generator tubing. The use of zinc injection to control radiation build-up BWRs and PWRs is being investigated.This report reviews efforts to enhance the reliability of nuclear power plants by improving materials performance, water chemistry, and plant design. Issues likely to come up in the future are also discussed.