Study Of Coal Dust Concentration Detection System Based On The Principle Of Transmission

In the process of coal mining operations, a lot of dust will be produced in the roadway, not only affects the operation of production, can also cause great harm to the health of workers mining, causing lung disease.And when the coal dust concentration reaches a certain limit and there is fire, it may cause a coal dust explosion, threating mine safety. Therefore, mine coal dust concentration monitoring has become an important part of coal mine production safety, timely and effectively monitoring of coal dust in the production process is necessary to take effective dust removal measures to ensure the safety of workers.In this paper, Twelfth Five-Year National Support Program "Real-time monitoring of the mine explosion hazard warning technology research2013BAK06B08" under-funded, developed around the target coal dust monitoring and early warning device, commonly used in the analysis and comparison of coal dust concentration at home and abroad on the basis of the detection method is proposed based on the combination of Lambert-Beer law and Mie scattering theory of coal dust concentration measurement methods.Based on the analysis of the coal dust concentration measurement principle on the basis of a transmission type, measured by the Mie theory of two small-angle scattering intensity ratio, the average diameter of the particles get coal dust, and then measure the degree of attenuation of the transmitted laser beam to calculate the concentration of coal dust, coal dust concentrations to achieve online measurement. Based on the analysis of the measurement system to measure a variety of factors that may cause errors, targeted design of the measurement system, will double the proportion of the optical path difference is applied to the measurement system to effectively eliminate measurement errors temperature changes, light fluctuations and other factors. In the coal dust concentration signal acquisition and analysis process for photoelectric sensors weak signal amplification and conversion process by adding a variety of noise signal processing using digital filtering algorithm by simulation and experiments validate the performance and reliability of the filtering algorithm.This paper completed coal dust measurement system software and hardware design, hardware includes a pre-amplifier circuit, A/D converter circuit, FPGA master control module, CAN bus communication circuits, display and sound and light alarm circuit and power supply circuit. FPGA design software design, including the mainprogram design, A / D data acquisition and data processing module filter design and CAN bus communication modules, etc.Finally, the coal dust concentration monitoring systems experimentally verified results in full compliance with design requirements.