硫酸钾钻井液体系的室内评价与应用

Laboratory Evaluation and Application of Potassium Sulphate Drilling Mud

受加拿大皇朝公司在宋芳屯油田州13区块采用硫酸钾钻井液成功进行油层保护的启发,在室内优选出的硫酸钾钻井液体系的基本配方为:5%膨润土+0.4%Na2CO3+5.0%K2SO4+1000mg/LDCL+200mg/LDesco+100mg/LAlcome+500mg/LSAP+1000mg/LLT+1000mg/LKEL,K+含量为50000mg/L时,钻井液具有合适的粘度、切力和滤失量,页岩滚动回收率大于85%,岩心静态膨胀率小于2%,岩心伤害率小于20%。其保护油气层的机理为:K+抑制粘土水化膨胀的能力、油层保护剂的吸附能力、K+与油层保护剂的协同作用。

Borrowing from Sunwing Energy Company (Ltd.) s experience of successfully using potassium sulphate drilling fluid in Block 13 in Song-fang-tun Oilfield to protect the reservoir from being damaged, we optimized the potassium sulphate mud in laboratory as this: 5% bentonite+0.4%Na_2CO_3+5.0%K_2SO_4+1000 mL DCL+200 mg/L Desco+100 mg/L Alcome+500 mg/L SAP+1000 mg/L LT+1000 mg/L KEL. The mud has a suitable viscosity, gel strengths and fluid loss if the concentration of the potassium ions in the mud is about 50 0...