Photoacoustic Combined Method Research Sensing For Gas And Dust In The Putty Room

gas(1,2-xylene) and dust(unsaturated polyester resin) particles are mainly caused by occupational factors,in the putty room, current 1,2-xylene gas concentration and the concentration of the unsaturated polyester resin is a separate independent testing, which employees work safety and prevention of occupational diseases is very unfavorable. This paper presents a photoacoustic method to meter 1,2-xylene and dust concentration simultaneously in the putty room. The putty room gas, including gaseous components and dust particles, were metered in the measuring cell between the light source and the photoacoustic cells. Based on gas filter technology and particle scattering theory, a 1,2-xylene gas cell and a reference gas cell(phenylethylene gas cell) were used together to meter the light attenuation caused by 1,2-xylene absorption and dust particles extinction at two different wavelengths. When the mine gas and coal dust entered the measuring cell, 1,2-xylene concentration and dust optical density were obtained by processing the photoacoustic signal attenuation of the two cells.According to the related photoacoustic filtering technology and principle of extinction, designed for use in the experiment of light spoke size. By the microphone and phase-locked amplifier device build the photoacoustic compound 1,2-xylene-dust concentration risk judgment device. Using this system to test each performance of the system, experiments show that the system of 1,2-xylene and dust concentration has very good response. Finally, through the establishment of the acousto-optic scattering light composite detection system of three layers BP neural network model, combined the BP network and fuzzy reasoning properly, alarm time composite algorithm is established. The experimental data show that the photoacoustic combined method can sense for 1,2-xylene and dust particles more accurately.