Domestic Fourier transform infrared spectroscopy monitoring technology opens a new era of vehicles

[ China Instrument Network Instrument Development ] In mid-October, the “VOCs Monitoring System for Vehicle Open Light Pavement Sources”, developed by Anguang and jointly promoted by Guoxin Juyuan Technology Service (Beijing) Co., Ltd., successfully delivered to Taiwan-funded enterprises, marking The domestic Fourier transform infrared spectroscopy monitoring technology system has opened the "new era of vehicles".

Fourier transform infrared spectroscopy technology has the characteristics of measurable spectral bandwidth, high spectral resolution, high signal-to-noise ratio and fast scanning speed. It has real-time, online, continuous and unattended monitoring capabilities for multi-component gases. At present, most of the Fourier transform infrared spectroscopy monitoring technology monitors the VOCs (volatile organic compounds) gas of fixed pollution sources in the upper and lower vents of industrial parks through ground fixed stations, and inverts the discharge flux of industrial parks.

With the frequent expansion of industrial parks, explosions and fires, and other sudden air pollution accidents, fixed ground station monitoring has limitations in locating emission sources. In response to the urgent need for rapid and accurate identification of pollutants under complex and dynamically changing environmental conditions in emergency emergencies in chemical parks, and to meet the requirements of use in harsh environmental conditions such as high temperature and high humidity at the accident site, the FTIR project of Anguang Institute The group set out to develop a vehicle open light pavement source emission monitoring system to quickly obtain the trend of pollutant diffusion in the accident area.

The vehicle open light pavement source emission monitoring system has the advantage of quick and flexible, and can perform non-contact, fast and automatic measurement of various pollutant gas emissions. The monitoring vehicle carrying the main engine and the array corner mirror are placed on both sides of the accident site in a short time, and the pollution gas emission situation at the accident site can be quickly obtained. In addition, the monitoring equipment has been widely used in the patrol inspection of toxic and harmful gases in the high-density pollution source area of ​​the chemical park, the monitoring of toxic and harmful gas leakage in the plant area, and the early warning of toxic and harmful gases in the perimeter of the plant.

The vehicle open optical path monitoring system puts higher requirements on the stability of the instrument and the accuracy of the optical system. The R&D personnel must ensure that the instrument can adapt to long-distance transportation bumps and maintain the spectral stability in the vehicle starting state. In the face of the challenge, the FTIR team of Anguang has ingeniously designed the structure of the spectrometer: because the structure of the classic Michelson interferometer is very demanding on the precision of the optical system, the alignment of the mirror and the scanning drive system, in order to reduce the classic Michelson interference. In the structure of the instrument, the influence of the tilt of the moving mirror reduces the alignment of the mirror and the driving performance of the moving mirror. The monitoring system adopts the structure of the double-arm swiveling interferometer independently developed. The interferometer structure uses a plane mirror to realize the original return of the beam, is insensitive to tilting, and is convenient for calibration of the device; in addition, it converts the linear motion of the moving mirror into the sweeping motion of the platform, compared with the linear motion of the classical Michelson interferometer. The sweeping motion can reduce the complexity of the moving mirror drive and is easy to implement, which can avoid the spectral distortion caused by the shape change during the movement of the classic Michelson interferometer. In March 2018, the in-vehicle system completed the demonstration of the vehicle, completed the vehicle modification in June, completed the joint debugging test of the vehicle-related equipment in September, and delivered it to the user in October for the inspection of toxic and harmful gas leaks.

Today, the first on-board open optical path monitoring system has been officially in operation. The introduction of this instrument has provided new technical support for the construction of monitoring capacity in China's parks, and will also enhance China's international competitive position in the field of high-end monitoring instruments.

(Original title: Anguang Institute "Car open light pavement source emission VOCs monitoring system" successfully delivered the domestic Fourier transform infrared spectrum monitoring technology system to open "car new era")