Difficult mining coal seam bottom plate thin layer limestone high-pressure strong aquifer karst fissure aggregate perfusion method

Abstract

The invention discloses a difficult mining coal seam bottom plate thin layer limestone high-pressure strong aquifer karst fissure aggregate perfusion method. The difficult mining coal seam bottom plate thin layer limestone high-pressure strong aquifer karst fissure aggregate perfusion method comprises the following steps that (1) aggregates are perfused at an opening of a drilling horizontal section, and aggregate perfusion is stopped after hole sealing of the aggregates; (2) hole sweeping is conducted, and then mixed slurry is perfused; (3) grouting is continued after an orifice device is added at a drilling opening, and cement slurry is injected; and (4) the cement slurry is injected to the opening, and when an orifice is at the normal pressure, perfusion is continued for 1 h. By adopting the technical scheme, the aggregate perfusion technology can rapidly fill large karst fissures; by means of the filling mode, a water resistant body is formed after aggregate filling, the filling process is shortened, and meanwhile, the defect that the perfusion plugging aggregates cannot reach the fissures easily due to repeated hole sweeping in the prior art is effectively overcome; the perfusion efficiency is improved; working face extraction is ensured; the water burst phenomenon is avoided; and the mining safety is ensured.

Description

technical field [0001] The invention belongs to the field of coal mining, and more specifically, the invention relates to a method for pouring aggregate into karst fissures of a thin-layer limestone high-pressure aquifer in a hard-to-mine coal seam floor. Background technique [0002] In the process of coal mining, when large-scale fractures are encountered during drilling, aggregates are used to fill the holes in the working face to block the karst fissures. This filling method is prone to aggregates blocking the drill holes, and it is difficult for the aggregates to reach the karst fissures. The existing technology uses repeated Sweeping holes, pouring plugging, this kind of plugging efficiency is low, it is difficult for the aggregate to reach the cracks to complete the plugging, resulting in the trouble of slurry running on the working face, and a large amount of groundwater gushing out of the cracks, resulting in the occurrence of water seepage accidents. Water gushing ...

AI Technical Summary

Problems solved by technology

[0002] In the process of coal mining, when large-scale fractures are encountered during drilling, aggregates are used to fill the holes in the working face to block the karst fissures. This filling method is prone to aggregates blocking the drill holes, and it is difficult for the aggregates to reach the karst fissures. The existing technology uses repeated Sweeping holes, pouring plugging, this kind of plugging efficiency is low, it is difficult for the aggregate to reach the cracks to complete the plugging, resulting in the trouble of slurry running on the working face, and a large amount of groundwater gushing out of the cracks, resulting in the occurrence of water seepage accidents. Water gushing occurs in mining, which even leads to landslides and other accidents, which brings potential safety hazards to mining

Images