钾铵基聚合物泥浆在大同煤田复杂地层钻进中的应用

煤田地质钻探中,白垩系卵石层、多层采空区及泥岩地层是一大钻进难题。一是上部长孔段砂卵层胶结松散,易垮塌;二是下部泥岩水敏性强,膨胀性大,节理裂隙发育,极易产生缩径、造浆及不同程度的渗漏;三是多层采空区的护壁问题。针对这些问题,在大同煤田复杂地层钻进中,经反复实验选用了钾铵基聚合物低固相泥浆。实践证明,采用钾铵基聚合物低固相泥浆,可有效防止孔内坍塌、掉块、缩径,预防孔内事故,提高钻进效率,降低成本,达到了正常的钻进目的。

Application of Potassium Ammonium Polymer Mud in Complex Formation Exploration Drilling of Datong Coalfield

Cretaceous gravel layer, multilayer goaf and mud stone formation have been difficult for coalfield geological drilling. Firstly, it is easy to collapse due to the loose cementation at upper sand gravel layer hole section; secondly, strong water sensitivity, high swelling, joint and fissure development easily cause hole shrinkage, mud making and different degrees of leakage at lower hole section; thirdly, the wall protection in multilayer goaf. In view of the above, in the complex formation drilling in Datong coalfield, potassium ammonium polymer low solid mud is selected by repeated tests. The practice proves that the accidents of hole collapse, block falling, hole shrinkage can be prevented by using potassium ammonium polymer low solid mud to improve drilling efficiency and reduce cost.