Online automatic measuring system for environment air quality based on low-temperature condensing method sampling

Abstract

The invention belongs to the measurement technical field of atmosphere environment quality, which specifically relates to an online automatic measuring system for environment air quality based on low-temperature condensing method sampling. The system is composed of a low-temperature condensing sampling system and an analyzing system; the low-temperature condensing sampling system comprises a drying pipe, an electronic cold trap and a low-temperature low trap that are connected in turn; the drying pipe is connected with an air inlet pipeline for removing vapor and condensing the environment air sample at low temperature; the analyzing system comprises a light source, a sampling battery, an optical spectrum instrument and a computer; the analyzing system splits and detects the air condensed by the sampling system through the optical spectrum instrument by the ultraviolet function from the light source and then analyzes the air by the computer. The system is high in integrated degree and measuring efficiency, which is suitable for continuous, real-time and online measurement of various pollutants of atmosphere environment (including sulfur dioxide, nitrogen dioxide, ozone, ammonia, formaldehyde and part of benzene series) in environment air.

Description

technical field [0001] The invention belongs to the technical field of atmospheric environment quality measurement, and in particular relates to an online automatic measurement system for ambient air quality. Background technique [0002] At present, in the field of atmospheric environmental quality measurement, the measurement of atmospheric pollutant gases, such as nitrogen dioxide, sulfur dioxide, and ozone, mainly includes air nitrogen dioxide, sulfur dioxide, and ozone automatic monitors, and long-range differential absorption spectroscopy gas pollution monitoring devices. [0003] When the automatic monitor is monitoring, the gas to be tested is directly pumped into the instrument through the sampling tube to make it chemically react with certain substances to emit light, or irradiate with ultraviolet light to produce fluorescence or use the principle of ultraviolet absorption for measurement. For example, when the nitrogen dioxide analyzer is working, the nitrogen dio...

AI Technical Summary

Problems solved by technology

However, the disadvantage of this type of instrument is that each instrument can only measure one kind of pollutant gas. If you want to build an ambient air quality monitoring station, you need a variety of such instruments to form a monitoring system. The construction cost is high and the system is complicated. , the instrument maintenance workload is heavy

[0004] For the existing long-range differential absorption spectroscopy gas pollution monitoring device, it works on the principle of characteristic absorption of certain wavelengths of light by gas molecules, and its working process is that the transmitting / receiving telescope is fixed at one end and placed at a distance of about 500m A corner reflector, the light emitted by the telescope reaches the corner reflector after being transmitted by the atmosphere, is reflected by the corner reflector and then received by the telescope, and then transmits the light to the spectrometer through the optical fiber for splitting. The light signal is detected by the detector and sent to the The computer performs spectral analysis to calculate the concentration of pollutants in the area where the light path passes. Because the measurement is performed with an open light path, the problem that this technology faces is that the measurement is greatly affected by meteorological conditions. If it is in a foggy day, severe haze In weather or heavy rain, due to the reduction of atmospheric visibility, the light attenuates greatly when it is transmitted in the atmosphere, and the light intensity returned to the instrument is too small for analysis, so the instrument cannot work, resulting in a decrease in the working efficiency of the instrument. Unable to work for longer than normal working hours

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