嵩县某金矿区复杂地层强抑制防塌泥浆技术

Strong inhibitive drilling fluid technology for complex formation in a gold mining area in Song county

摘要:

嵩县某金矿区钻遇地层复杂，岩石破碎，部分地层绿泥石化、高岭石化严重，钻进过程中缩径、垮塌、漏失、涌水等多种复杂情况频发，断钻杆、粘卡、烧钻等事故层出不穷。在对比邻近矿区施工经验的基础上，总结了本地区钻孔施工的技术难点，对比分析了分散泥浆、无固相聚乙烯醇泥浆、低固相聚合物泥浆的使用效果。结果表明，高浓度膨润土浆具有防塌、防漏、胶结松散岩石等多种功能，配制简单且使用方便，可用于上部覆盖层钻进。对于下部复杂地层，常规分散泥浆体系抑制性不足，难以应对该矿区复杂工况；无固相聚乙烯醇泥浆前期防塌能力强，但是处理坍塌事故能力不足；低固相聚合物泥浆体系抑制性强，流变性良好，防塌能力强，取得了良好的使用效果。

Abstract:

Complex formation， unconsolidated， chloritized， water sensitive， was encountered when drilling in a gold mineral area in Song county， leading to complex conditions in the drilling process， including borehole shrinkage， collapse， leakage， water outburst， broken drill pipes， sticking， burnt drill tools， so and so forth. In correlation with the drilling experience in adjacent mining areas， this paper presents the drilling difficulties in this area， and analyzes the effect of different kinds of mud， including dispersed mud， solid-free polyvinyl alcohol mud， and low-solid polymer mud. The results show that， （1） High-concentration bentonite slurry has multiple functions such as anti-collapse， anti-leakage， and cementing loose rocks. It is simple to prepare and easy to use， and can be used for drilling in overburden. （2） The dispersed mud cannot meet the demand of the complex strata because of poor inhibition； the solid-free polyvinyl alcohol mud has high anti-caving capacities in the early drilling stage， but insufficient ability to deal with collapse. （3） Field applications of the low-solid polymer mud show that it can provides high inhibitive， good rheology and strong prevention of collapse.