Pressurized water reactor nuclear power plant first circulation starting primary loop deoxidization method based on acid condition

Abstract

The invention relates to the technical field of coolant deoxidization, in particular to a pressurized water reactor nuclear power plant first circulation starting primary loop deoxidization method based on an acid condition. The method comprises the following steps: L1, subjecting an effluent temporary storage tank to nitrogen purging; L2, vacuumizing a primary loop coolant system; L3, filling theloop with water; L4, dynamically exhausting the primary loop; L5, establishing nitrogen coverage of the effluent temporary storage tank; L6, establishing degassing circulation between a vacuum degassing tower and the effluent temporary storage tank; L7, starting a main pump to measure the total gas content; L8, calculating the addition amount of hydrazine; L9, adding the hydrazine in a voltage stabilizer main spraying mode; L10, judging the leakage of a check valve to confirm whether the hydrazine is added and uniformly mixed or not, if so, closing the spraying of the pressure stabilizer andentering L11 and otherwise, returning to L9. On the premise that no volume control box or acid condition exists, through combination of an improved physical deoxidization technology and a chemical deoxidization technology, the deoxidization speed is greatly increased, the occupied critical path time is shortened, and the deoxidization difficulty without the volume control box or the acid conditionis relieved.

Description

technical field [0001] The invention relates to the technical field of coolant deoxygenation, in particular to a method for deoxygenating a primary circuit of a pressurized water reactor nuclear power plant based on acidic conditions. Background technique [0002] Dissolved oxygen exists in the coolant of the primary circuit of the pressurized water reactor power station. Dissolved oxygen will cause uniform corrosion of system equipment under high temperature conditions, increase the sensitivity of metal materials to SCC (stress corrosion cracking), and shorten the service life of equipment. And the corrosion products will generate activated products under the irradiation conditions of the primary circuit, which will increase the radiation dose of personnel during the overhaul. Therefore, the dissolved oxygen content is required to be less than 100ppb before the temperature of the primary circuit rises to 121°C. [0003] Existing deaeration methods for the primary circuit o...

AI Technical Summary

Problems solved by technology

In the deoxygenation process of the first cycle start-up and temperature rise of the primary circuit, there is no irradiation condition, which greatly restricts the chemical deoxygenation speed and seriously affects the critical path of unit startup

Images