High-purity or toxic fluid recovery device

Abstract

The invention discloses a high-purity or toxic fluid recovery device comprising an inner-layer pressure container, a middle-layer pressure container, an outer-layer vacuum container, a thermal switchof the inner-layer pressure container, pipelines and valves of all the containers and the like. The inner-layer pressure container is used for containing high-purity or toxic fluid media; an annular closed space formed by the middle-layer pressure container and the inner-layer pressure container can be filled with liquid nitrogen or other low-temperature fluid; the outer-layer vacuum container canprovide a vacuum environment to reduce heat leakage; the thermal switch connected with corrugated pipes is designed between the inner-layer pressure container and the outer-layer vacuum container; and on and off of the thermal switch can be achieved on the premise that vacuum is guaranteed. When the middle-layer pressure container is filled with the liquid nitrogen or other low-temperature fluid,low vapor pressure is obtained in the inner-layer pressure container, and therefore recovery of the high-purity or toxic fluid is achieved. The high-purity or toxic fluid recovery device is convenient to use, easy to maintain and rapid in response, miniaturization and integration of the device are achieved, and the device can be in a standby state for a long time.

Description

technical field [0001] The invention relates to occasions where high-purity or toxic fluids are used. In industrial production or scientific experiments, these fluids need to be recycled and used because they are expensive, or cannot be discharged at will because they are toxic and harmful. Specifically, it is a recovery device for high-purity or toxic fluids , suitable for fluid recovery occasions. Background technique [0002] In the liquid xenon dark matter detection experiment represented by PandaX, xenon gas with a purity of more than 99.9995% needs to be used, and the krypton content in xenon gas has also been reduced to 1ppt or even 0.1ppt. At the same time, the price of xenon gas is very expensive, so it must be Recover high-purity xenon, and in the course of the experiment, in order to prevent accidents, you must also be prepared to recover high-purity xenon. Existing xenon gas recovery technology, one method is to use a diaphragm compressor to fill xenon gas into ...

AI Technical Summary

Problems solved by technology

The second method is to put the gas cylinder or pressure storage tank in the open Dewar, and then fill it with liquid nitrogen to cool, and the xenon gas will condense or desublimate on the inner surface of the gas cylinder or pressure storage tank. Condensation or desublimation of xenon heat resistance becomes larger and larger, so that the recovery rate decreases synchronously

This method has three shortcomings, which brings more difficulties to the operation and maintenance of the experimental device

First of all, the liquid nitrogen in the open Dewar volatilizes quickly, and the injected liquid nitrogen is quickly consumed. Most of the time, the Dewar and the internal gas cylinder or pressure storage tank are at room temperature, and an additional device is required to supply liquid nitrogen; secondly. , it takes a long time to start injecting liquid nitrogen into the Dewar until the gas cylinder or pressure storage tank has the recovery ability, and it does not have the instantaneous recovery ability, and the dynamic response characteristics are poor; third, the liquid nitrogen in the Dewar is at the bottom, and the gas The liquid xenon that condenses on the inner surface of the cylinder or pressure storage tank will also gather at the bottom. At this time, the position that needs cooling most is the middle and upper part of the gas cylinder or pressure storage tank, that is, liquid nitrogen cannot effectively cool the gas cylinder or pressure storage tank. The effective utilization rate of nitrogen is low, which is inconvenient in relatively closed underground laboratory space or occasions where it is difficult to obtain liquid nitrogen

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