Atmosphere volatile organic compound condensation and concentration sampling device and method

Abstract

The invention discloses an atmosphere volatile organic compound condensation and concentration sampling device which comprises a low-temperature environmental cabinet and an atmosphere sampler, wherein a low-temperature cold trap device is arranged in the low-temperature environmental cabinet, and comprises a first-stage cold trap and a second-stage cold trap, the first-stage cold trap comprises a first condensation pipe and a first semiconductor chilling plate group, a first heating wire is wound on the first condensation pipe, the second-stage cold trap comprises a second condensation pipe and a second semiconductor chipping plate group, and a second heating wire is wound on the second condensation pipe. The invention also discloses an atmosphere volatile organic compound condensation and concentration sampling method. The atmosphere volatile organic compound condensation and concentration sampling device and method disclosed by the invention are capable of meeting the demand on online automatic monitoring of the content of a volatile organic compound, and can be used in on-site online automatic monitoring of the content of the atmosphere volatile organic compound.

Description

technical field [0001] The invention relates to the technical field of atmospheric environment detection equipment, in particular to a sampling device and sampling method for condensing and concentrating atmospheric volatile organic compounds. Background technique [0002] Most of the volatile organic compounds contained in the atmosphere have teratogenic, carcinogenic, mutagenic and other hazards, and are important culprits of atmospheric photochemical hazards and greenhouse effects. Real-time detection of volatile organic compound content is increasingly important, especially online monitoring of volatile organic compound content in the field is increasingly important. At present, the detection of volatile organic compounds in the atmosphere is mainly done through chromatographic analysis. Since there are many types of volatile organic compounds in the atmosphere and their concentrations are low, enrichment and concentration treatment must be carried out to meet the detec...

AI Technical Summary

Problems solved by technology

However, this method consumes a lot of liquid nitrogen, and the cost of refrigeration is high. At the same time, liquid nitrogen is replaced in the field, storage is difficult, and the analysis cycle is long, which brings great inconvenience to use and maintenance. Therefore, it is not suitable for continuous on-line monitoring in the field.

Moreover, porous adsorbents are commonly used in low-temperature cold traps in the current technology, which can quickly thermally desorb volatile organic compounds after low-temperature adsorption. In this process, cross-contamination and "memory effect" are easy to occur.

Therefore, the current condensation concentration device and condensation concentration method cannot meet the needs of online monitoring of volatile organic content

In addition, the use of porous adsorbents to adsorb volatile organic compounds takes a long time for desorption, which prolongs the entire analysis cycle and is prone to cross-contamination problems between different sample analyses.

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