Mine Gas Sensor Unattended Calibration And Exhaust Gas Treatment System

Coal mine production safety is related to the life safety of the operators andstate property, mine gas sensor is the primary detecting element for mine safetymonitoring system and the top priority of the coal mine safety monitoringsystem, which is used for monitoring a variety of toxic and harmful gasconcentration of coal mine, the coal mine gas sensor’s sensitivity and reliabilityis the key technical index of coal mine safety monitoring system. During thelong-term use process, the gas sensor may show zero drift, so the coal minesafety regulation formulates that gas sensor should be calibrated regularly.Currently, the manual adjustment reduced the accuracy and increased the workintensity, automatically adjusts only achieve5-8sets of sensors simultaneouslydetected and sequentially adjusted by infrared remote control, which unable tomeet the present situation of a large number of gas sensors’ calibration by coalmining enterprises. According to calibration requirements, there should pass intocalibration gas three times, and each time continued for90~120s, so the gaswould be spread in the calibration laboratory, and most manufacturersdischarged directly to the outside by the fan, which can affected the health of theoperators and polluted the air quality. Therefore, the development of a set ofunmanned calibration and exhaust gas treatment system has important practicalsignificance, which can achieve a mass of sensors’ calibration and process theexhaust gas to ensure safety and environmental quality.Based on the gas sensor working principle, the waste gas treatmenttechnology, developed the design scheme of the system, designed a set ofunattended calibration and exhaust gas treatment system, which select C8051F020microcontroller as the core control unit. The information collectionsubsystem was mainly to complete the acquisition of output signals of mine gassensors, the acquisition of output signals of gas sensors and temperature sensorfor monitoring. The automatic control subsystem was mainly to complete thecontrol of intake calibration gas, hardware design of the system, compiled eachfunction module of the system, the control of driver of exhaust gas treatmentdevice, the control of infrared output signals, the expansion of ecternal datamemory. The system can achieve verification and calibration for64mine gassensor, designed a real-time system on various types of sensor to send variousinfrared calibration instruction, which can realize automatic closed-loopverification and calibration, used TiO2loaded on ACFS photochemical catalysisoxidation to decompose toxic exhaust, used BP neural networks to predict thedosage of purifying material.The system realizes the large quantities of coal mine gas sensor closed-loopautomatic adjustment, which can improve work efficiency and calibrationprecision and reduce labor and the cost of invesrment and maintenance ofadjustment equipment. The system also realizes to decompose and purify thetoxic and harmful waste gas in the calibration chamber, which can ensure theoperators’ physical safety and the environment quality. The system is in thestage of trial operation, the test result shows that the system is running well, hashigh accurate of the control process, strong ability of real-time data, has goodanti-jamming capability and stability, the effect of exhaust gas treatment isobvious and in accordance with the national emission standards, it realizes thefunction of mine gas sensor unattended calibration and exaust gas treatment.