According to the mining plan requirements of the mine in 2015, the 1319 working face to be excavated is located in the north of the 1318 goaf water accumulation area. The terrain is high in the south and low in the north. The 1319 planned heading face and the 1318 goaf water floor are nearly 20 meters apart. The 1319 planning auxiliary return airway coal pillar is only 25 meters. If the water in the empty area is not discharged in advance, it will directly affect the mining safety of the 1319 working face. The company's research decided to advance the water in the 1318 goaf. In order to ensure the safety of the exploration and release of water in the empty area, the following safety technical measures are formulated. I. Overview of the 1318 goaf The 1318 goaf is located in the 350-1000m area of ​​the original 1318 working face on the east side of the 1300 track. The north side is 1319 to be excavated, the east side is 1400 track lane, and the south is 1317 goaf. The original coal seam in the empty area moves from northwest to southeast and turns east and west, tending to the northeast. According to the measured data of the roadway provided by the Geodetic Survey Section, the elevation of the lowest point of the roadway is 511m, the elevation of the 700-1000m section is basically close, the dip angle of the coal seam is 1.5-2 degrees, and the empty area is 145,000 square meters. . At the beginning of 1318, the rupture of sandstone from the top of the roof was poured into the well. The maximum water inflow was 60m3/h. After the end of mining, the water inflow was stable at 6-8 m3/h. With the increase of the empty area and the tunneling of the return airway of the new wind well, In the empty area, the water inflow from the water outlet of the 1300 track lane gradually decreased, and the flow broke out in June 2013. According to the "Report on the Classification of Mine Hydrogeological Types", since the goaf has been closed and it is impossible to conduct on-the-spot observation, the No. 3 coal seam is adopted according to the calculation formula of the old empty area water in the "Coal Safety Manual" Estimation of water accumulation in the empty area, the projected area of ​​the 1318 empty water area is 77,032 m2, the average mining height is 4.59 m, the coal seam inclination is 50, and the water accumulation is 88,732 m3. The opening height of the 1318 return air duct in the 1300 track lane is 540m, the lowest elevation of the working surface is 511m, the drop is 29m, and the hydrostatic pressure in the stagnant water area is lower than 0.3Mpa. Second, the status of mine water and drainage 1. The current water in the underground is mainly from the goaf, and the water inflow is 43m3/h. Mainly from the goaf, the new wind shaft, the 1400 roadway roof anchor cable drilling water seepage. 2. Drainage system, one main and two auxiliary water tanks in the mine, the capacity is 1522m3, the central pump house is equipped with 3 MD155-30×10 pumps, and the single pump drainage capacity is 150m3/h (combined drainage test report data). The water volume is about 43m3/h, and the average daily drainage time of the central water tank is 7-8 hours. There are two temporary water tanks in the 1400 roadway, with a volume of 54m3. A total of four D85-46×6 pumps are arranged. Two diameters of 140mm pipes are directly connected to the central water tank. The single pump drainage capacity is 70m3/h, and the original 1400 lanes are 1320. The water inflow is 10 m3/h, the water inflow is 4m3/h, the kilometer rig has an average displacement of 7m3/h, and the total is 21m3/h. The water pump has a drainage capacity of 40-50m3/h, and the 1320 is used during the discharge. Temporary water tank behind. Third, the construction location The construction location is determined according to the elevation of the floor of each exposed roadway and the most suitable water discharge location in the 1400 track lane. The 1322 auxiliary air inlet is 215-227 meters south, and the floor elevation is 500.225-502.05m (the distance is the horizontal distance has been carried out by the geodetic department). Calibration). Fourth, the construction method The water stop casing is installed at the orifice, and the ZDY-1200S full hydraulic tunnel drilling rig is used for drilling and discharging water. Fifth, the construction steps 1. Preparation before construction Before the construction, the production department coordinated the relevant teams to dredge the two temporary water tanks of the 1400 return air lane (now the intake air), clean the drainage ditch and the sedimentation tank, and arrange the power supply, switch and communication for the construction site. Electromechanical equipment such as telephones. The exploration and drainage team moved the rig to the construction site. First, at the 1400 track auxiliary lane of the 1400 track lane, 175 meters to the south, along with the slope of the roadway, the specification is 3×1.5×0.5m slag pool (brick), in the track lane 1322 Auxiliary inlet wind tunnel goes south, and the damper goes north according to the slope of the roadway to build a 3×2×0.5m sedimentation tank (brick) to prevent the water from rushing into the water tank. 2. The geotechnical technician has provided the elevation of the bottom plate of the roadway to support the drilling rig. When drilling the water hole, the azimuth of the drilling hole and the inclination angle of the drilling hole are determined on site. 3. The drilling is carried out using ZDY-1200S type tunnel hydraulic explosion-proof drilling rig. The installation is stable and fixed. The fixing method is to flatten the rig and use a single column to press the top plate on the top plate to take anti-collapse measures. Before fixing, it should be The floor of the roadway is clear to the hard bottom. 4, install the water stop casing Firstly, use a 114mm drill bit to make a 10m deep hole, and use a 130mm reaming drill bit to ream the hole. The length of the hole is 10m (the length of the sealing pipe for the old water body is not less than 10m, and the maximum height of the 1318 empty area is 29m, the maximum The hydrostatic pressure is 0.29 MPa) and the diameter of the 110 mm orifice casing is fixed by a high-pressure grouting pump to press the 525-grade cement slurry into the hole, and the fixed length is 10 m. (The orifice tube standard is shown in the attached drawing). The required pressure is not less than 1 MPa. 5. Withstand voltage test, after sealing for 30 minutes, install the orifice DN100 gate valve and Y-100 type 1.5Mpa pressure gauge, connect the dustproof static pressure water into the orifice tube, and stop the water injection after the pressure gauge value is greater than 1MPa, 30 minutes. The orifice tube is not loose, does not leak water, and begins to relieve pressure when the pressure does not drop. 6. The depth of the hole should be more than 0.3m from the length of the orifice tube. Six, explore the water 1. After the casing test is completed, install the DN100 valve and the Y-100 type 0.6MPa pressure gauge for the hole before the drilling. After adjusting the azimuth and inclination of the drilling, use the Φ75 drill bit to drill forward. Empty area, after drilling 2m into the empty area, stop drilling. When drilling and drilling water, the three common hoses of the orifice tube are connected. The water and slag are directly discharged into the slag pool. During the drilling, the cinders in the slag pool are cleaned up in time. Coal slime is strictly prohibited from flowing into the roadway. Due to the different pressures such as the weight and propulsion of the drill bit and the drill pipe during the drilling process, the drilling is prone to deflection due to changes in geological conditions and the rotation of the operator. Therefore, the stability of the driller should be maintained. 2. Drilling arrangement: Five holes are preliminarily designed, four are water drilling holes, and one is (hole No. 2) as a verification hole. The drilling holes are arranged at 215-227 meters south of the auxiliary air inlet of the 1400 track lane 1322, and one hole is arranged at intervals of 3 meters. The borehole is an inclined hole and is detected upward along the coal seam. The construction sequence is 5-3-1-4-2, and it is determined whether to arrange further exploration and drainage water engineering according to the actual drilling conditions. No. 1 hole: position 215m, floor elevation 500.22m, support height 1.4m, azimuth 257 degrees, elevation 8°; Hole 2: Position 218m, floor elevation 500.52m, support height 1.4m, azimuth 257 degrees, elevation 7.8°; Hole No. 3: position 221m, base plate elevation 500.88m, branch height 1.4m, azimuth 257 degrees, elevation angle 7.5°; Hole 4: Position 224m, floor elevation 501.15m, support height 1.4m, azimuth 257 degrees, elevation 7.3°; Hole 5: Position 227m, floor elevation 501.54m, height of the support 1.4m, azimuth 257 degrees, elevation angle 7°. 3. After the drilling is completed, in order to prevent the drilling hole from being blocked, the drill pipe can not be pulled up temporarily, and it is reserved for the purpose of sweeping the hole in the hole, and then the drill pipe is lifted after the water flow is stable. Sixth, release water 1. When the drilling and drilling of the water is completed, the flood control team shall use the valve on the tee to control the water discharge amount ≤35m3/h, which is not greater than the drainage capacity of a D85-45*6 water pump in the temporary water tank. 2. The water control office monitors and monitors the water discharge process, records the drilling and water discharge in real time, monitors the water pressure change in the hole, and monitors the single hole displacement with the flow meter flow meter. 3. The underground electric team records the water pump drainage operation record. 4. If the water volume changes abnormally during the discharge, report to the dispatching room immediately, and then find out the cause. 5. If the drilling is blocked during the discharge, the water rig should be cleaned by a drilling rig. 6. Drainage, empty water along the 1400 track roadway drain to the 1322 auxiliary air inlet dam door at the door 1400 return wind alley 1#, 2# temporary water tank, D85-45*6 water pump through the 1400 roadway drain The road drains to the central water tank and then drains to the ground. Seven, verify that the empty area is drained If there is no water in the water drilling hole, firstly, according to the total amount of water discharge, it is judged whether there is still water in the empty area. Secondly, the water exploration team will sweep all the holes with ZDY-1200S drilling machine, and the hole must be hit to the empty area for more than 5m. , to confirm whether the hole is blocked. Finally, the hole No. 2 is used to verify whether the water in the empty area is drained. If there is no water in the verification hole, it is confirmed that the water in the empty area has been drained, and the water discharge is completed. Eight, drilling construction requirements The drainage hole is drilled by the exploration and drainage team, and each person in charge is responsible for coordinating the construction of each class. 1. The operator is not allowed to leave the rig when drilling, and does “three lookâ€, “two listens†and “one timelyâ€. That is to see the operation (gear) handle vibration, feed pressure and footage speed, see the pump pressure gauge and return water condition, see the water joint situation; listen to the machine running sound, listen to the vibration inside the hole; find abnormal treatment in time. 2. Calculate the drilling depth correctly, and calculate the more accurate azimuth and inclination for the next hole according to the drilling situation. 3. Strictly implement the maintenance and inspection system of the drilling rig. Before the construction, the drilling rig and its auxiliary installations should be maintained once. The drill pipe joints, thread wear and bending degree should be carefully checked. It is strictly forbidden to use the drill pipe of poor quality. 4. If a mechanical failure or sudden power failure occurs during the drilling process, the power switch should be pulled open immediately, and the drilling tool should be manually pointed out to the safety hole section to avoid drilling. 5. The on-the-spot labor organization is: one team leader, four water and water crew members, one safety officer, one gas player, and one rescue team. Nine, safety technical measures a) Drilling construction safety measures 1. Connect the power supply line and set up a special telephone near the water exploration site to ensure good communication and ventilation at the construction site. 2. Check the top support of the water exploration site. The drillway and the roadway support within 10 meters before and after it must be firm and reliable. 3. It is necessary to clear and dig the drainage ditch along the way to ensure that the water output of the drilling hole before the water and the drill pipe are not withdrawn before drilling can be discharged in time. During the drilling construction process, after installing the orifice tube, the orifice safety valve (withstand voltage 1.0MPa) should be installed immediately. The drilling tool should be drilled from the valve into the hole. During the drilling process, the valve should be opened to the maximum. Position, in the process of drilling the upper and lower drilling tools, should be careful to prevent the valve from being damaged. Before and after the drilling, check the opening and closing of the valve to ensure that the valve is good. If the valve is found to be damaged, stop drilling immediately and replace the valve. 4. Strict on-site handover system. When shifting the shift, the shifting depth, drilling depth, drilling equipment operation status and existing problems must be handed over. Before starting work, you must check the roof and the support of the two gangs, and find out the problems in a timely manner. 5. It is strictly forbidden to bump the valve during the drilling process. Before the borehole is near the water, the valve should be inspected to ensure reliable performance. During the drilling process, it is found that when the coal rock is soft, the amount of water pressure in the sheet, the pressure or the borehole suddenly increases, and the top drill is abnormal, the drilling must be stopped, but the drill must not be pulled at will. The drilling tools were fixed in time, and the person in charge of the on-site construction immediately reported to the dispatching room and sent people to monitor the water situation. If the amount of water is too large and the water pressure is too high, all personnel at the water-threatening site must be evacuated immediately and measures taken. 6. During the construction of the drilling, the construction site must maintain sufficient air volume, and the wind must be withdrawn. A portable gas alarm is installed at the construction site to monitor the gas concentration. When the gas concentration exceeds 1.0%, the construction must be stopped, the power supply must be cut off, and the person should be evacuated. During the process of water exploration, the inspectors and ambulance members must be on duty at the scene to check the air composition. If the concentration of gas or other harmful gases exceeds the limit, the drilling must be stopped immediately, the power supply must be cut off, the orifice valve should be closed, and the mine dispatching room should report to the mine dispatching room. . If necessary, evacuate the personnel and handle them. 7. When the drilling hole is near the water and drilled through the old air, the person in charge of the on-site construction immediately reports to the dispatching room. The dispatching room arranges the temporary water tank drainage personnel to prepare for drainage, ready for drainage. The 1400 roadway is removed before the displacement is stable. There shall be no other noisy personnel in the outer lane of the drainage crew of the underground electromechanical team. 8. The protective cover of all equipment must be complete and effective. 9. Mechanical and electrical equipment maintenance should be notified to the electrician of the full-time machine for maintenance. The power supply must be cut off during maintenance. The switch to cut off the power supply must be suspended from the power-off operation card or taken care of. After the power failure, the qualified test pencil must be used to check, discharge, and hang the grounding wire. 10. It is strictly forbidden to electrify and relocate equipment. 11. During the construction of the drilling, it is necessary to ensure that the water in the goaf is drilled and the water is discharged. According to the amount of water discharged, it is determined whether or not the water discharge hole is arranged. b) Water release safety technical measures 1. The water is discharged by using one hole for drilling and the remaining holes for spare. 2, 1400 roadway temporary water tank, equipped with 2 D85-45*6 water pump, take turns to drain, do not allow a pump to run 24 hours without interruption. According to the operation of the pump, timely maintenance work is required. 3. In principle, the water is kept in accordance with the two pumps alternately for 24 hours without interruption. The underground electromechanical team is responsible for the whole process. If the pump fails, it needs timely maintenance and overhaul. It is not allowed to close the drain valve if there is operation and backup pump. If there is a special situation, the water can not be discharged in time, and the drainage valve can be closed for maintenance after reporting the cause to the dispatcher. 4. The amount of water discharged from the hole should not be too large and too strong to prevent blockage of the borehole. If the accumulated water scoured the particulate matter to block the borehole, in addition to adjusting the remaining borehole displacement, it should report to the dispatching room in time, and arrange the personnel of the water exploration team to eliminate the blockage in time. 5. During the drainage period, the water pump duty personnel must not leave the post without authorization, and strictly carry out the on-site handover. IX. Division of duties 1. The dispatching room is mainly responsible for contacting and coordinating the work of all departments, and timely notifying the miners and issuing various instructions when receiving emergency reports. 2. The ventilation department is mainly responsible for the operation and management of the ventilation facilities at the site, and the inspection of toxic and harmful gases such as gas to ensure safe and reliable ventilation. 3. The exploration and release team is mainly responsible for designing and constructing, implementing safety technical measures, ensuring construction safety, completing construction tasks and managing the whole process of water discharge. If the drilling is blocked during the drainage process, it is responsible for re-opening the hole. 4. The geodetic survey department is responsible for providing the opening position required for drilling, the floor elevation, the drilling elevation angle and the azimuth angle, and calibrating on site, following the on-site observation of the drilling construction situation, and measuring and adjusting the drilling according to the situation during the drilling process. angle. 5. The Water Control Office is mainly responsible for the preparation of the water discharge design, on-site inspection and acceptance of the installation quality of the orifice tube, on-site supervision of the drilling construction, tracking and observation of the water discharge and water pressure (water level). 6. The underground electromechanical team is mainly responsible for the installation and operation of communication and drainage facilities, construction and electricity use, management of the water tank sedimentation tank, timely cleaning of debris in the ditch, and ensuring smooth drainage. 7. The ambulance team is responsible for detecting the disposal of toxic and harmful gases other than gas and carbon dioxide during the process of detecting and releasing water, and the implementation of emergency measures. 8. The Safety Supervision Department is responsible for the supervision and inspection of the implementation of the measures in the construction and the investigation of hidden dangers on the site. 9. The comprehensive excavation team is responsible for the construction of the slag discharge tank and the cleaning of the sedimentation tank and drainage ditch during the process of water exploration and discharge. Ten, drainage route Construction site - 1400 track lane - 1400 temporary water tank - 1322 auxiliary wind tunnel Φ140 pipe - 1300 belt lane Φ140 pipe - central water tank - auxiliary inclined shaft Φ194 drain pipe - ground XI. Disaster avoidance route 1400 track roadway→1322 auxiliary air inlet lane→1300 track lane (or 1300 belt lane)→West track lane→hole bottom yard→main, paying inclined shaft→ground Hdpe Drainage Pipe,High Pressure Hdpe Pipe,Gb Hdpe Pipe,Butt Welding Hdpe Pipe SHANDONG DONGHONG PIPE INDUSTRY CO., LTD , https://www.donghongpipe.com
Technical measures for water safety in goaf