Drainage system and method for underground nuclear power plant cavern group

Abstract

The invention discloses a drainage system and a drainage method for an underground nuclear power plant cavern group. The drainage method comprises the steps that accumulated water in an underground nuclear power plant cavern flowing out via a drainage hopper is monitored by means of a radioactivity monitor, a controller shuts off a first isolation valve when the radioactivity monitor monitors that the accumulated water is radioactive, the controller opens a second isolation valve, the radioactive accumulated water enters a drainage branch associated with radioactivity, and is discharged into a siphon well after being treated by a radioactive substances treatment room; when the radioactivity monitor does not monitor that the accumulated water is radioactive, the controller shuts off the second isolation valve and opens the first isolation valve, and the non-radioactive accumulated water is discharged into the siphon well; and the accumulated water is discharged to rivers outside a mounting by means of the siphon well. According to the drainage system and the drainage method, the passive drainage system is constructed by utilizing a siphon pipeline and the siphon well, negative pressure formed in a siphon device forces water in the pipeline to flow under pressure, the flow velocity is accelerated, the drainage effect is good, and the drainage system can discharge the accumulated water out of the underground cavern in an organized and efficient manner regardless of accidental water accumulation or serious accident conditions.

Description

technical field [0001] The invention belongs to the technical field of underground nuclear power, and in particular relates to a drainage system and method for cavern groups of an underground nuclear power plant. Background technique [0002] Underground nuclear power plants set up multiple caverns underground or in the mountain to accommodate the reactor building and other auxiliary buildings, and use the natural rock mass as the last physical barrier of the principle of defense in depth to ensure the safety of the reactor. [0003] The underground cavern communicates with the outside environment through inlet and outlet pipes, vents, and exhaust pipes. The existence of these passages may cause accidental water inflow into the cavern. If the water inflow cannot be discharged in time, it will cause water accumulation in the cavern, and there is a possibility of flooding. , affecting the normal operation of various systems and equipment, resulting in the failure of the specia...

AI Technical Summary

Problems solved by technology

However, this seepage and drainage method can only discharge the seepage water in the water layer of the rock mass, and cannot discharge the large amount of accumulated water in the cavern in time.

[0006] The accumulated water in caverns of underground nuclear power plants may contain radioactivity and pollute groundwater. Therefore, the existing drainage systems and methods for underground projects cannot be simply copied. Special consideration must be given to the disposal of radioactive accumulated water.

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