Method for calculating containment leakage rate under special working conditions

Abstract

The invention belongs to the technical field of nuclear leakage rate calculation, and particularly relates to a method for calculating a containment leakage rate under special working conditions, themethod comprises seven steps. The method is characterized by comprising the following steps: step 1, drawing a limit value curve of the leakage rate deltaP-Qleak of a new containment; step 2, queryingQp historical data of a unit needing to be monitored, and selecting a relatively large value; 3, comparing the calculated value with a limit value; step 4, performing result judgment; step 5, performing pressure change analysis; step 6, performing temperature change analysis; and step 7, ending the reverse calculation. The method has strong executability, can accurately calculate the leakage rateof the containment under special working conditions, and can realize timely and effective monitoring of the integrity of the containment every day, i.e., the effective monitoring of the integrity ofthe containment is shortened from 5 days to 1 day, and the timeliness is realized.

Description

technical field [0001] The invention belongs to the technical field of nuclear leakage rate calculation, and in particular relates to a method for calculating the leakage rate of containment under special working conditions. Background technique [0002] 1) Brief introduction of containment leakage rate [0003] The containment vessel is the third safety barrier of a nuclear power plant and is a prestressed concrete structure with a steel liner that limits the release of radioactive gases to the environment. During the normal operation of the unit, the containment vessel was in a closed state, but the leakage of the containment vessel was caused due to the incorrect online status of the penetrating parts. In order to protect the radiation safety of the public, the power plant has set up an online monitoring system for the containment leakage rate (hereinafter referred to as the "monitoring system") to monitor the containment leakage rate during the operation of the unit on-...

AI Technical Summary

Problems solved by technology

[0018] In the actual monitoring process, it is found that when the monitoring system is restarted in the initial stage and the unit is in special working conditions such as the state change of the primary circuit before and after the overhaul, the calculation of Ql60 by the monitoring system has a problem of insufficient timeliness

[0019] From the two conditions for calculating Ql60, it can be seen that after the monitoring system is restarted and the unit is overhauled, the △P-Qld leakage rate curve needs to be re-fitted. Monitoring of containment integrity is inactive

[0020] At the same time, if there is a real abnormality in the integrity of the containment, the range of △P cannot meet the condition of greater than 1.5kPa, and the monitoring system will always be unable to calculate Ql60, which will affect the judgment of the technicians on the integrity of the containment, and delay the inspection of the completeness of the containment. The timely handling of abnormal problems brings risks to the safe and stable operation of the unit, and also loses the significance of monitoring the integrity of the containment

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