Method for controlling concentration of sulfate radical of pressurized water reactor nuclear power plant unit-loop

Abstract

The invention provides a method for controlling concentration of sulfate radical of a pressurized water reactor nuclear power plant unit-loop. The method comprises the following steps of (1) clearing cation resin in a purification unit B of a spent fuel pool and boron box water purification system (3); (2) circulating according to an order of a boron water storage system (2), the spent fuel pool and boron box water purification system (3), the spent fuel pool (1) and the boron water storage system (2) after a nuclear power plant unit is shut down in a cold state; (3) restoring a mode of two cation beds and an anion bed of the spent fuel pool and boron box water purification system (3) to run when the concentration of the sulfate radical of a loop cooling agent is controlled below 500mug / L; and (4) stopping circulating when the concentration of the sulfate radical is greater than 500mug / L, clearing the cation resin in the purification unit C, and running in a mode of a single anion bed. An extra system facility does not need to be increased; the extra chemical agent does not need to be added to change the water quality; and the target of removing the sulfate radical can be achieved by adjusting the running mode of the purification system.

Description

technical field [0001] The invention belongs to the technical field of nuclear power plant operation, and in particular relates to a method for controlling sulfate radical concentration in a primary circuit of a pressurized water reactor nuclear power plant unit. Background technique [0002] The Tianwan Nuclear Power Plant in Jiangsu Province, China uses pressurized water reactor nuclear power plant units imported from Russia. During the overhaul period, the primary circuit coolant and the spent fuel pool of the two units of the Tianwan Nuclear Power Plant experienced an abnormal increase in sulfate radicals during the overhaul period, and the trend was year by year. The upward trend, from the highest concentration of 300 μg / L during the second overhaul of Unit 1, to the highest concentration of the two units during the third overhaul is close to 1500 μg / L. If the excessively high sulfate radicals are not removed in time, the fuel cladding and the primary circuit pipeline m...

AI Technical Summary

Problems solved by technology

[0005] Judging from the research information of domestic and foreign counterparts, there is no information and experience that can be used to remove sulfate radicals. Russian nuclear power plants have also encountered the same problem. Some nuclear power plants have a maximum concentration of sulfate radicals of 3000 micrograms per liter, and some power plants have carried out 2 years of scientific research, but the real source has not been identified so far, and the removal of sulfate radicals is naturally impossible to start

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