黑山煤田封堵涌水孔段的浆液和注浆方法

黑山煤田处于沙漠边侧,地层有纯砂粒构成的、透水性较強的中细砂层,这类地层中如含有承压水时,会发生钻孔涌水,对于中细砂涌水钻孔,用泥浆冲孔时,可通过适当增大泥浆相对密度,来压制地下水涌出,ZK18-28孔是涌水孔,也是采用绳索取心钻进的孔,因此不宜使用高相对密度泥浆。用套管亦未奏效。若用注浆法,对于中细砂层是不适用水泥浆的。而溶液型浆液的注浆封堵中细砂层,在技术有可行性,对于涌水压力不大的孔,又有可用低强度,因而也是低成本的浆液,因此选择了比较亷价的水玻璃类的SPN浆液,并采用双隔离塞的注浆法,在ZK18-28孔中取得了封堵中细砂涌水层的初步封堵效果。

Slurry and grouting method for blocking water inrush hole section in Heishan coalfield

Heishan coalfield is located on the edge of desert.There are medium and fine sand layers with pure sand grains and strong permeability.If there is confined water in these layers,water gushing from boreholes will occur.For boreholes with water gushing from medium and fine sand,groundwater gushing can be suppressed by properly increasing the relative density of mud when drilling with mud.ZK18-28 boreholes are water gushing holes.It is also a hole drilled by wire-line coring,so it is not good to use high relative density mud.The use of casing also failed.If grouting method is used,cement slurry is not suitable for medium and fine sand layer.The grouting method of solution grout is feasible in technology to plug the medium-fine sand layer.For the holes with low water inflow pressure,it can also use low strength,so it is also a low-cost grout.Therefore,SPN grout of sodium silicate with comparative price is selected,and double isolation plug grouting method is used to plug the medium-fine sand inflow in ZK18-28 holes.Preliminary plugging effect has been achieved.