Volatile organic compound online monitoring system

Abstract

The invention discloses a volatile organic compound online monitoring system. The volatile organic compound online monitoring system comprises a sampling probe, a tracing pipe, a preprocessing system, a monitoring host, a sampling pipeline, a carrier gas pipeline, a carrier gas source, a fuel gas source, a combustion-supporting gas source and a data processing and displaying unit, wherein the sampling probe is connected with the preprocessing system by the tracing pipe; the preprocessing system is connected with the sampling probe and the monitoring host; the monitoring host is connected with the preprocessing system, the carrier gas source, the fuel gas source, the combustion-supporting gas source and the data processing and displaying unit; the carrier gas source is connected with the monitoring host; the fuel gas source is connected with the monitoring host; the combustion-supporting gas source is connected with the monitoring host; the data processing and displaying unit is connected with the monitoring unit. According to the volatile organic compound online monitoring system disclosed by the invention, at most 15 minutes are spent for obtaining a group of sampling data of benzene series, higher time resolution is obtained, the running cost and the maintaining cost are low, the operability is strong, and the volatile organic compound online monitoring system is particularly suitable for continuous and automatic online detection of volatile organic compounds discharged by a stationary source.

Description

technical field [0001] The invention relates to the technical field of gas monitoring, in particular to a system capable of continuously monitoring the concentration of volatile organic compounds on-line. Background technique [0002] According to the definition of the World Health Organization, volatile organic compounds (volatile organic compounds, VOCs) refer to a class of organic compounds with a boiling point of 50-250 °C, a saturated vapor pressure of more than 133.32 Pa at room temperature, and existing in the air in the form of vapor at room temperature. VOCs have a wide range of polarity and concentration, and at a certain concentration, they have the risk of carcinogenesis, teratogenicity, mutagenesis and leukemia. VOCs are the decisive precursors of photochemical smog and the main precursors of PM2.5. Reliable VOCS measurement data is the basis for studying its impact on the environment and human health. The monitored VOCs are affected by factors such as source ...

AI Technical Summary

Problems solved by technology

[0004] 1) The current various sampling methods have certain defects in the sampling process, for example: air bag sampling is not used much now due to the adsorption and analysis effects on the inner wall; the stainless steel sampling tank needs to be sent back to the laboratory for adsorbent concentration Or low-temperature pre-concentration treatment, although it can avoid the penetration and artificial pollution of adsorbent sampling, but it is expensive to perform multiple analyzes and requires complex equipment cleaning

Although adsorbent sampling and low-temperature sampling can complete the pre-concentration of samples at the same time as sampling, they require low-temperature transportation and storage

[0005] 2) The above-mentioned sample collection method must be pretreated before it can be used for analysis. Due to the complexity of the pretreatment process and the artificial contamination of the sample during pretreatment, the entire process takes a long time. , and will bring some error

[0006] 3) For the detection of volatile organic compounds, the most commonly used methods are gas chromatography and gas chromatography-mass spectrometry, but most of them use off-line analysis technology, which has low time resolution and cannot reflect the concentration of various substances in VOCs over time. Fine changes, at the same time, the sampling and analysis process has high technical requirements for personnel

[0007] In my country, the research on volatile organic compounds started relatively late, and the collection and analysis of volatile organic compounds mainly relied on large-scale analysis equipment and instruments from abroad, which were not only expensive, but also complicated in the analysis process, and the time resolution of sampling and analysis was very poor. There is still a large gap between actual needs

Images