聚胺钾盐钻井液在哥伦比亚南部区块的应用

Application of Polyamine Potassium Drilling Fluid in South Columbia

哥伦比亚南部Jazmin区块地质构造和地层岩性比较复杂,特别是Umir地层水化膨胀造浆非常厉害.Umir地层由灰色和黑色的泥岩构成,并间歇性掺杂有煤层,属于典型的三角洲平原沉积.该区块大致分3种类型,Ⅰ类储层孔隙度大于33％,渗透率大于8μm2;Ⅱ类储层孔隙度为29％～33％,渗透率为7.5～9 μm2;Ⅲ类储层孔隙度为25％～29％,渗透率为5～7.5μm2.通过采集该区块岩屑与港内的明化镇组岩心膨胀性等分析对比,决定用聚胺钾盐体系,该体系中的主剂YH-SUP、YH-COA、YH-LUB通过相互协同作用可以在井壁岩石和钻屑表面形成膜,很大程度地提升了体系的抑制性和润滑性;该钻井液性能稳定,抗污染能力强,并且无毒,易生物降解,较好地满足了当地环境保护要求,且现场应用效果良好,特别针对Umir地层的强水敏性泥岩以及LaLuna上部易剥落掉块页岩有着显著效果,缩短了钻井液处理时间,保障了井壁稳定和井下安全.

Block Jazmin in the south Columbia has complex geological structure and lithology, especially the Umir Formation which is very water sensitive. The Umir Formation is aminly composed of grey and black claystones intercalated intermittently with coal beds, showing a typical characteristics of delta plain sedimentation. Reservoirs in this block are classified into three kinds; class I has a porosity of greater than 33% and a permeability of greater than 8 μm2, class II has a porosity of 29%-33% and a permeability of 7.5-9 μm2, and class III a porosity of 25%-29% and permeability of 5-7.5 μm2. Cuttings samples were taken for analysis and comparison with the Minghuazhen Formation cuttings from China, and a polyamine potassium drilling fluid was decided to use in this block based on the comparison. The main additives of the polyamine potassium drilling fluid, YH-SUP, YH-COA and YH-LUB form a coating film through synergistic effect on the surface of rocks and drilled cuttings, increasing the inhibitive capacity and lubricity of the drilling fluid. The polyamine potassium drilling fluid has stable property and good contamination tolerance, and is environmentally friendly. Sloughing and collapse of water sensitive zones in the Umir and Laluna formations are controlled and safe drilling realized.