(2) Injection molding (water glass) is beneficial to the management of the top plate and solidifies the top plate. It can also greatly reduce the amount of gas emission and prevent gas accidents. (3) After injection, the surrounding rock forms a complete whole, which can better solve the problem of pumping and leakage and improve the pumping effect. (4) After injection, it is beneficial to roof management, eliminates roof accidents, and effectively controls watering near the geological structure belt. (5) Draining after injection is the most effective way to control gas gushing anomalies in geological structure belts, and can solve the technical problems of tunneling safety. 3 Conclusions (1) High-gas mines in the mining roadway with geological structural belts and large gas emission, and can be promoted and applied; (2) After water injection glass, the pumping effect is improved, and the working surface is safe. Excavation conditions have accelerated the construction speed of mines and reduced costs. Door Hinges,Car Door Hinge,Cabinet Door Hinge,Concealed Door Hinge Gangling Hardware produce factory , https://www.ganglinggd.com
Geological control technology
Dragon coal mine inclined Central Coal five construction a construction, wellbore azimuth N46oW, from the wellhead to the main slope inclination is 12o down the mountain at 443m, 443m ~ 667m as at 6o down, 667m ~ 944m to 3 ‰ drift, which When drilling to 830m, a reverse fault (N350oS) falls 8m. A large amount of high-pressure gas is stored in the fault zone. The section of the roadway has a semi-circular arch shape with a net cross section of 16.2 m2 and is supported by an anchor net. The gas emission area is +1163m high and 187m deep from the ground. 1 Gas management of working face (1) On August 28, 2004, the amount of gas emission increased from the original 1.2m3/min to 4.2m3/min when the main inclined shaft was constructed to 830m. Due to the abnormal gas emission, the working face was forced to stop the excavation. The method of first pumping and excavating was adopted. The main well was headed and the lane was used to construct the gas drainage hole. The TX-75 drilling rig was used to drill the Φ75mm hole to the working surface. (2) From the period of September 18, 2004 to January 20, 2005, a total of 374,976 m3 of gas was discharged. Gas drainage decreased from 4.15m3/min to 1.2m3min, and gas concentration decreased from 40% to 20%. The temporary pumping system was withdrawn and the pumping was stopped for 3 days for testing. The gas emission was still high and the safe tunneling could not be guaranteed. (3) In order to do a good job in gas control, the temporary drainage system was changed to the ground permanent drainage system, and the diversion chamber was made on both sides of the 820m roadway with length × width × height = 2 × 2.5 × 2m. Drilling holes were drilled in the diverting chambers, and the pumping was started from January 28, and the amount of gas discharged was 3.5 m3/min. (4) In order to further accelerate the effect of gas control in the main inclined shaft, the tunneling will be resumed as soon as possible. According to the broken roof of the roadway and the large amount of gas escaping, the method of pumping can not meet the characteristics of safe excavation conditions. Starting from February 20, the main The well-injected glue (water glass) is used to seal the head-on crack (see Table 1 and Figure 1). The injection pressure is 1 MPa, and the water glass is 650 kg. After 1 day, the concentration of gas in the head wind was reduced from 0.5% to 0.15%. The problem of abnormal gas in the head blast was solved, and then the excavation was resumed. The gas concentration in the backflow airflow was up to 0.45%, and the geological structure gas emission was smoothly passed. Anomalous areas for safe production. 2 Key technologies and innovations (1) Sealing process and continuous pumping of pipes and other items that are sealed on the ground. The sealing material is Φ25mm PVC pipe, PVC pipe length is 3m/root, and each hole is 6m (2 pieces) One of the ends is made of a 600 mm long mesh tube. 2 Wrap the cotton yarn at 700mm from the end of the PVC pipe (ie 100mm outside the mesh hole section). 3 After the mortar has been solidified, the PVC pipe and the gas drainage “multi-pass†can be connected by a hose. 4 When the pipe is connected, the pipe cannot be on the same side of the cable. It is required that the pipe is hung neatly and the interface cannot be leaked.