现河庄油田牛872块油井酸化液体系优选实验

Optimization experiment of acidizing fluid system in oil well of Niu872 bock in Xianhezhuang Oil-field.

为了优选现河庄油田牛872块油井的酸化液体系,在实验室通过测定地层岩心酸溶失率,评价了矿场常用酸化液体系对储层岩石的溶蚀作用,研究了酸化液与岩石反应的时间效应和温度效应。研究表明,土酸、潜在土酸能够溶蚀充填在孔隙喉道中的粘土矿物成分,改善渗流性能,可作为牛872块油井酸化液体系;酸化后岩石渗透率提高的主要原因是酸蚀通道的形成,较快的酸注入速度和相对合适的反应时间能够促进酸蚀通道的形成及数目的增加;较小的潜在土酸用量不能控制副反应的发生,较大的潜在土酸用量可有效提高近井地带的渗透率。模拟地层条件的岩心流动实验结果验证了酸溶失率实验的准确性。

In order to optimize the acidizing fluid system of oil well in Niu872 bock of Xianhezhuang Oilfield,corosion action of common acidizing fluid system in field to res-ervoir rocks was evaluated and the effect of temperature and time of the reaction between the acidizing fluid and rocks was researched by measuring corrosion ratio of formation core in the laboratory.The results show that mud acid and potential mud acid may be used as the a-cidizing fluid system of Niu872 block since it can im-prove the percolation capacity by corroding the clay minerals filled in the pore throats.Corroded channel formed after acidizing is the main reason of permeabili-ty increase,rapid acid injection speed and relatively suitable reaction time may promote the formation of the corroded channel and the amount increase of it.Low potential mud acid dosage can not control to side reac-tion to occur;high dosage of potential mud acid may in-crease near-well-bore permeability.The result of core flow test for simulating formation condition has proved the accuracy of the acid corrosion ratio experi-ment.