煤矿井下暂堵转向水力压裂技术研究

Research of temporary plugging diverting fracturing technology in underground coal mine

为更好地提高煤层透气性,结合煤矿井下压裂应用现状和暂堵转向压裂技术原理,本文创造性的提出了将暂堵转向压裂技术应用于煤矿井下水力压裂的思路,目的是着力于转向形成新裂缝并沟通煤层自有天然裂缝以强化煤岩缝网复杂程度,提高压后瓦斯抽采效果。研究结果表明:暂堵转向压裂技术适应性较强,可用于煤矿井下压裂;优选了适合煤矿井下压裂的小粒径水溶性MKZD-1暂堵剂,1.0cm厚滤饼承压可达40MPa,封堵能力强,溶解性好,压后其水不溶物约为4%;设计了煤矿井下实施暂堵转向压裂的工艺流程和暂堵剂加量方法。本文研究成果为煤矿瓦斯治理提供了新手段,开辟了新方向,具有一定的实际运用和推广价值。

In order to improve the permeability of coal seam,combined with the present situation of underground fracturing in coal mine and the principle of diverting hydraulic fracturing in temporary plugging,the idea of applying temporary plugging to hydraulic fracturing in coal mine is put forward creatively.The purpose is to focus on forming new fractures and communicating natural fractures in coal seam to enhance the complexity of coal seam network and improve the effect of gas drainage after treatment.The results show that the technique is adaptable and can be used in underground fracturing of coal mine.The water-insoluble MKZD-1 temporary plugging agent suitable for underground coal mine fracturing.It has strong plugging ability,1.0 cm thick filter cake can reach 40 MPa under pressure.It also has good solubility with about 4%water insoluble residue after treatment.The process flow and the method of adding quantity of temporary plugging agent in coal mine are designed.The research results of this paper provide new means and new direction for coal mine gas control,which has certain practical application and popularization value.