Gas capture concentration device and working method thereof for improving gas measurement sensitivity

Abstract

The invention discloses a gas capture concentration device for improving gas measurement sensitivity. The gas capture concentration device comprises a flow-controllable mass flowmeter, at least three stages of semiconductor cold traps, a pump, a piston type gas collecting device, a rod type stepper motor, a valve a, a valve b, a valve c, a valve d and a valve e. The gas capture concentration device has the advantages that multiple gases within a temperature range can be simultaneously frozen and captured, the influence of moisture and other gas components is avoided and the gases can be analyzed one after one by adjusting different analysis temperatures, refrigeration is rapid, operation is simple, reliability is strong, high-control precision over temperature is realized, pollution is avoided, and the like.

Description

(1) Technical field: [0001] The invention relates to a gas-capturing and concentrating device and a working method thereof, in particular to a gas-capturing and concentrating device and a working method thereof for improving the measurement sensitivity of volatile organic gases and toxic and harmful gases in the atmosphere. (two) background technology: [0002] At present, the methods of trapping volatile organic gases and toxic and harmful gases in the atmosphere include trapping with deactivated quartz empty capillary cryogenic traps, trapping at room temperature in adsorption tubes, trapping with liquid nitrogen refrigeration in adsorption tubes, and trapping with mechanical refrigeration. [0003] In the patent ZL201410223586.8 of Li Hongjie et al., the capture method for polar and non-polar organic gases has been described. The metal tube wound on the cooling head is used to refrigerate through heat conduction. The temperature of the metal capture tube can be adjusted. ...

AI Technical Summary

Problems solved by technology

The disadvantage is that the area required for the quartz hollow capillary must be large enough to fully capture the gas, which makes the equipment relatively bulky and cumbersome, and not flexible enough

[0005] With the decrease of evaporating temperature of mechanical refrigeration, the initial investment cost of equipment will be higher and higher, which increases the cost of obtaining unit cooling capacity to a large extent. It is difficult for mechanical refrigeration to precisely control the temperature in a short time. When it is low (in the temperature range above -70°C), the equipment investment of liquid nitrogen refrigeration method is higher than that of mechanical refrigeration method, which is not economical

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