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CN-116677378-B - Quantitative coal mining control system for preventing coal mine gas from exceeding limit

CN116677378BCN 116677378 BCN116677378 BCN 116677378BCN-116677378-B

Abstract

The invention discloses a quantitative coal mining control system for preventing coal mine gas overrun, which comprises a gas volume fraction monitoring probe, a safety pre-warning and monitoring module and a gas overrun quantitative control module, wherein the gas volume fraction monitoring probe comprises a monitoring probe T 1 arranged at one end of a transportation roadway close to a coal mining working surface, a monitoring probe T 2 arranged on the coal mining working surface, a monitoring probe T 3 arranged at one end of a return air roadway close to the coal mining working surface, a monitoring probe T 3 arranged at one end of the return air roadway close to the coal mining working surface, a monitoring probe T 4 arranged at one end of the return air roadway far from the coal mining working surface, and the monitoring probe T 1 , the monitoring probe T 2 , the monitoring probe T 3 and the monitoring probe T 4 are respectively connected with the safety pre-warning and monitoring module and the gas overrun quantitative control module.

Inventors

  • YAO SHIJIE
  • GAO YOUJIN
  • LI HUAMIN
  • LI BAOCHAO

Assignees

  • 郑州普泽能源科技有限公司

Dates

Publication Date
20260505
Application Date
20220328

Claims (6)

  1. 1. The quantitative coal mining control system for preventing the coal mine gas overrun is characterized by comprising a gas volume fraction monitoring probe, a safety early warning and monitoring module and a gas overrun quantitative control module, wherein the gas volume fraction monitoring probe comprises a monitoring probe T 1 arranged at one end of a transportation roadway close to a coal face, a monitoring probe T 2 arranged at the coal face, a monitoring probe T 3 arranged at one end of a return roadway close to the coal face, a monitoring probe T 4 arranged at one end of the return roadway far from the coal face, and the monitoring probe T 1 , the monitoring probe T 2 , the monitoring probe T 3 and the monitoring probe T 4 are respectively connected with the safety early warning and monitoring module and the gas overrun quantitative control module; the control operation of the gas overrun quantitative control module comprises the following steps: S71, setting a working face gas safety volume fraction C Safety device ; S72, determining the actual working face gas concentration T 3 Actual practice is that of according to the monitoring probe T 3 ; S73, calculating absolute gas emission quantity under the safe concentration, wherein the calculation formula is as follows: Q 1 =C Safety device *Q*K/100; Wherein Q 1 is absolute gas emission quantity under the safety concentration, m 3 /min;C Safety device is the safety gas concentration,%, Q is return air quantity, m 3 /min, and K is a safety coefficient; s74, calculating the absolute gas emission quantity of the actual working surface, wherein the calculation formula is as follows: Q 2 =T 3 Actual practice is that of *Q/100; Wherein Q 2 is the absolute gas emission quantity of the actual working surface, m 3 /min;T 3 Actual practice is that of is the gas concentration of the actual working surface,%; s75, calculating the allowable gas emission amount of the working face, wherein the calculation formula is as follows: Q Allow for =Q 1 - Q 2 ; Wherein Q Allow for is the absolute gas emission amount allowed to be increased/decreased by the working surface, m 3 /min;Q 1 is the absolute gas emission amount under the safe concentration, m 3 /min;Q 2 is the absolute gas emission amount of the actual working surface, and m 3 /min; S76, calculating the working face mining-discharging coordination ratio under the current cycle, wherein the calculation formula is as follows: P Coordination of picking and placing =J Coal caving /J Coal mining ; wherein P Coordination of picking and placing is the ratio of the coal mining efficiency and the coal discharging efficiency of the current working face,% >, J Coal caving is the number of the coal discharging brackets under the current cycle, and J Coal mining is the number of the coal discharging brackets under the current cycle; s76, setting a picking and placing standard coordination ratio interval; S77, comparing the working face mining-discharging coordination ratio with a mining-discharging standard coordination ratio, if the working face mining-discharging coordination ratio is in a standard coordination ratio interval, increasing or decreasing the coal mining speed and the number of coal discharging ports simultaneously, if the working face mining-discharging coordination ratio is smaller than the standard coordination ratio interval, increasing the number of the coal discharging ports firstly when the working face needs to increase the gas emission quantity, increasing the coal cutting speed secondly, decreasing the coal cutting speed firstly when the working face needs to decrease the gas emission quantity, decreasing the number of the coal discharging ports secondly, and if the working face mining-discharging coordination ratio is larger than the standard coordination ratio interval, increasing the coal cutting speed firstly when the working face needs to increase the gas emission quantity, increasing the number of the coal discharging ports secondly, and decreasing the number of the coal discharging ports firstly and then decreasing the coal cutting speed when the working face needs to decrease the gas emission quantity; s78, calculating the variable coal cutting speed, wherein the calculation formula is as follows: V Allow for =Q Allow for /（Q Phase (C) *B Depth of cut *H Coal mining *ρ Coal ); Wherein V Allow for is the allowable increasing/decreasing coal cutter speed, m/min, Q Allow for is the allowable increasing/decreasing absolute gas emission quantity of a working face, m 3 /min;Q Phase (C) is the relative gas emission quantity of coal, m 3 /t;B Depth of cut is the cutting depth of the coal cutter, m, H Coal mining is the cutting height of the coal cutter, m, ρ Coal is the coal volume weight, t/m 3 ; S79, calculating the number of the variable coal discharge ports, wherein the calculation formula is as follows: Q Allow for =mt 2 +kt+a; ; Wherein Q Allow for is the absolute gas emission amount allowed to be increased/decreased by the working surface, m 3 /min, t is the quantity allowed to be increased/decreased by the coal discharging port, and m, k and a are constants.
  2. 2. The quantized coal mining control system for preventing coal mine gas overrun according to claim 1, wherein the safety pre-warning and monitoring module comprises a working face concentration overrun pre-warning unit, a coal and gas outburst pre-warning unit, a goaf gas emission quantity prediction unit, a coal mining gas emission quantity prediction unit, a coal discharging gas emission quantity prediction unit and a stabilization stage coal wall emission quantity prediction unit, wherein the working face concentration overrun pre-warning unit performs pre-warning operation through a pre-set pre-warning interval and detecting whether a monitoring probe T 1 , a monitoring probe T 2 and a monitoring probe T 3 are located in the pre-warning interval, and the coal and gas outburst pre-warning unit performs pre-warning operation through detecting gas concentration and gas concentration increment of the monitoring probe T 3 .
  3. 3. The quantized coal mining control system for preventing coal mine gas overrun according to claim 2, wherein the prediction operation of the steady-stage coal wall emission prediction unit includes the steps of: S31, acquiring relevant coal and rock, arranging a gas monitoring probe at a lower tuyere under laboratory conditions, performing a simulation experiment by adopting fresh air with the same flow rate as that of a roadway, and counting time variation samples of exposure time and gas volume fraction in the laboratory; S32, drawing a scatter diagram of the exposure time and the gas emission volume fraction of the coal wall through multiple experiments, and obtaining a gas emission rule curve of the coal wall by filtering and fitting the scatter diagram; S33, calculating the gas concentration C Unstable coal wall in the unstable coal wall gas release stage, the gas concentration C Coal wall in the coal wall gas stable release period T Coal wall stabilization and the gas concentration C Coal wall in the coal wall gas stable release stage according to a coal wall gas emission rule curve y=a+b×e ct , wherein y is the volume fraction of the coal wall gas, T is the exposure time, and a, b and C are parameters to be fitted; S34, calculating to obtain absolute gas emission quantity of the coal wall gas stable release stage according to the gas volume fraction value and the air quantity of the coal wall gas stable release stage, wherein the calculation formula is as follows: Q Coal wall insulation =QC Coal wall /100; Wherein Q Coal wall insulation is absolute gas emission quantity in the stable release stage of the coal wall gas, m 3 /min, Q is return air quantity, and m 3 /min;C Coal wall is gas concentration in the stable release stage of the coal wall gas.
  4. 4. The quantized coal mining control system for preventing coal mine gas overrun according to claim 3, wherein the prediction operation of the goaf gas emission prediction unit comprises the steps of: S41, stopping coal mining at the coal mining machine, stopping coal discharging at the tail of the bracket, and when the coal discharging stopping time exceeds a gas stable release period T Coal wall stabilization , the gas emission quantity of the working face=the absolute gas emission quantity of the goaf+the absolute gas emission quantity of the coal wall in the gas stable release stage; S42, a calculation formula of the absolute gas emission quantity Q Goaf insulation of the goaf is as follows: Q Goaf insulation =Q Work surface for stopping production -Q Coal wall insulation = Q（T 3 Stopping production -T 1 Stopping production ）/100- Q Coal wall insulation ; The device comprises a goaf, a working face, a coal wall gas stable release stage, a monitoring probe T 3 and a monitoring probe T 1 , wherein Q Goaf insulation is the absolute gas emission quantity of the goaf, m 3 /min;Q Work surface for stopping production is the working face gas emission quantity when the coal mining and coal release stop time exceeds T Coal wall stabilization , m 3 /min;Q Coal wall insulation is the absolute gas emission quantity of the coal wall gas stable release stage, m 3 /min, Q is the return air quantity, m 3 /min;T 3 Stopping production is the gas concentration monitored by the monitoring probe T 3 when the coal mining and coal release stop time exceeds T Coal wall stabilization , and T 1 Stopping production is the gas concentration monitored by the monitoring probe T 1 when the coal mining and coal release stop time exceeds T Coal wall stabilization .
  5. 5. The quantized coal mining control system for preventing coal mine gas overrun according to claim 4, wherein the prediction calculation formula of the coal mining gas emission prediction unit is: Q Coal mining valve =Q Phase (C) *（B Depth of cut *V Coal mining *H Coal mining *ρ Coal ); Wherein Q Coal mining valve is the absolute gas emission quantity of coal mining of the coal mining machine, m 3 /min;Q Phase (C) is the relative gas emission quantity of coal, m 3 /t;B Depth of cut is the cutting depth of the coal mining machine, m is V Coal mining is the cutting speed of the coal mining machine, m/min, H Coal mining is the cutting height of the coal mining machine, m is rho Coal is the coal volume weight, and t/m 3 .
  6. 6. The quantized coal mining control system for preventing coal mine gas overrun according to claim 5, wherein the prediction operation of the drainage gas emission amount prediction unit includes the steps of: s61, stopping mining by the coal mining machine, and under the normal coal discharging state of the tail part of the support, calculating the absolute gas emission quantity of the coal discharging of the tail part of the support according to the following formula: Q Put out 1 = Q（T 3 Stopping production -T 1 Stopping production ）/100- Q Coal wall insulation - Q Goaf insulation ; q Put out 1 is the absolute gas emission quantity of coal discharged from the tail part of the bracket in the stop state of the coal mining machine, m 3 /min, Q is the return air quantity, m 3 /min;Q Coal wall insulation is the absolute gas emission quantity of coal wall gas in the stable release stage, m 3 /min;Q Goaf insulation is the absolute gas emission quantity of a goaf, and m 3 /min; S62, normally mining by the coal mining machine, and under the state that the tail part of the bracket is normally put, calculating the absolute gas emission quantity of the unstable coal wall by the following formula: Q Unstable coal wall = QC Unstable coal wall /100; Wherein Q Unstable coal wall is the absolute gas emission quantity of the unstable coal wall, m 3 /min, Q is the return air quantity, and m 3 /min;C Unstable coal wall is the gas concentration in the gas release stage of the unstable coal wall; S63, normally mining the coal machine, and under the state that the tail of the bracket is normally put, calculating the absolute gas emission quantity of the coal put at the tail of the bracket by the following formula: Q Put out 1 = Q（T 3 Stopping production -T 1 Stopping production ）/100- Q Unstable coal wall - Q Goaf insulation ; Q Put out 1 is the absolute gas emission quantity of coal discharged from the tail part of the bracket in the stop state of the coal mining machine, m 3 /min, Q is the return air quantity, m 3 /min;Q Unstable coal wall is the absolute gas emission quantity of the unstable coal wall, m 3 /min;Q Goaf insulation is the absolute gas emission quantity of the goaf, and m 3 /min; S64, drawing a scatter diagram of the number of coal discharge ports and the emission quantity of coal discharge gas, and fitting to obtain a functional relation of the number of the coal discharge ports and the emission quantity of the coal discharge gas, wherein the functional relation is as follows: q=mn 2 +kn+a; Wherein q is the emission amount of coal-discharging gas, m 3 /min, n is the number of coal-discharging ports, and m, k and a are constants.

Description

Quantitative coal mining control system for preventing coal mine gas from exceeding limit Technical Field The invention relates to the field of coal mining, in particular to a quantized coal mining control system for preventing coal mine gas from exceeding the limit. Background Along with the continuous development of the coal mining industry, a plurality of gas emission quantity prediction analysis methods for each area of a working surface exist at present, but most of the gas emission quantity prediction analysis methods only play a role in prediction and alarm, cannot carry out self-adaptive adjustment on the coal cutting speed according to the gas concentration, have poor using effect, and the existing gas concentration feedback control method cannot accurately increase or reduce the coal cutting quantity and the coal discharge quantity according to the on-site actual coal mining and discharge coordination requirement, so that the accurate management and control of coal mining and discharge coordination and gas safety cannot be realized, and a certain trouble is brought to coal mining work. Disclosure of Invention Aiming at the problems, the invention provides a quantized coal mining control system which is simple in structure and capable of improving safety performance and preventing coal mine gas from exceeding the limit. In order to achieve the above object, the technical scheme of the present invention is as follows: The quantitative coal mining control system for preventing the coal mine gas overrun comprises a gas volume fraction monitoring probe, a safety early warning and monitoring module and a gas overrun quantitative control module, wherein the gas volume fraction monitoring probe comprises a monitoring probe T 1 arranged at one end of a transportation roadway close to a coal mining working face, a monitoring probe T 2 arranged at the coal mining working face, a monitoring probe T 3 arranged at one end of a return air roadway close to the coal mining working face, a monitoring probe T 3 arranged at one end of the return air roadway close to the coal mining working face, a monitoring probe T 4 arranged at one end of the return air roadway far from the coal mining working face, and the monitoring probe T 1, the monitoring probe T 2, the monitoring probe T 3 and the monitoring probe T 4 are respectively connected with the safety early warning and monitoring module and the gas overrun quantitative control module. The safety early warning and monitoring module comprises a working face concentration overrun early warning unit, a coal and gas outburst early warning unit, a goaf gas emission quantity prediction unit, a coal mining gas emission quantity prediction unit, a coal discharging gas emission quantity prediction unit and a stable-stage coal wall emission quantity prediction unit, wherein the working face concentration overrun early warning unit carries out early warning operation by presetting an early warning interval and detecting whether a monitoring probe T 1, a monitoring probe T 2 and a monitoring probe T 3 are positioned in the early warning interval or not, and the coal and gas outburst early warning unit carries out early warning operation by detecting the gas concentration and the gas concentration increment of the monitoring probe T 3. Further, the prediction operation of the steady-stage coal wall emission prediction unit includes the following steps: S31, acquiring relevant coal and rock, arranging a gas monitoring probe at a lower tuyere under laboratory conditions, performing a simulation experiment by adopting fresh air with the same flow rate as that of a roadway, and counting time variation samples of exposure time and gas volume fraction in the laboratory; S32, drawing a scatter diagram of the exposure time and the gas emission volume fraction of the coal wall through multiple experiments, and obtaining a gas emission rule curve of the coal wall by filtering and fitting the scatter diagram; S33, calculating the gas concentration C Unstable coal wall ,m3/min in the unstable coal wall gas release stage, the gas concentration C Coal wall ,m3/min in the coal wall gas stable release stage and the coal wall gas stable release period T Coal wall stabilization according to a coal wall gas emission rule curve y=a+b+e ct, wherein y is the volume fraction of the coal wall gas,% is the exposure time, min, and a, b and C are parameters to be fitted; S34, calculating to obtain absolute gas emission quantity of the coal wall gas stable release stage according to the gas volume fraction value and the air quantity of the coal wall gas stable release stage, wherein the calculation formula is as follows: Q Coal wall insulation ＝QC Coal wall /100; Wherein Q Coal wall insulation is absolute gas emission quantity in the stable release stage of the coal wall gas, m 3/min, Q is return air quantity, and m 3/min;C Coal wall is gas concentration in the stable release stage of the coal wall ga