酸性气田碳酸盐岩储层抗盐抗酸性气钻井液技术

Technology of salt resistance and acid gas pollution resistance drilling fluid for carbonate reservoir in sour gas field

刘晓栋 崔应中 王宇宾

LIU Xiaodong CUI Yingzhong WANG Yubin

天津中油渤星工程科技有限公司，天津　300451 荆州市汉科新技术研究所，湖北荆州　434000 中国石油集团工程技术研究院，天津　300451

Tianjin Boxing Engineering Technology Co, Ltd, CNPC, Tianjin 300451, China Jingzhou Hanke New Technology Research Institute, Jingzhou 434000, China Research Institute of Engineering Technology, CNPC, Tianjin 300451, China

为预测酸性气田钻井作业所用钻井液中酸性气的侵入量，根据地质参数和钻井参数计算了现场酸性气侵入量和除硫剂碱式碳酸锌与二氧化碳清除剂氧化钙的加量。为评价酸性气污染对钻井液性能的影响，设计了一套酸性气对钻井液污染的室内评价方法——气瓶压力控制灌注法，并根据理想气体状态方程，推导了灌注不同浓度酸性气体所需要的灌注压力计算公式。室内采用此方法评价了H2S、CO2对适合于南帕斯气田碳酸盐岩储层无黏土相NaCl盐水钻井液和无固相甲酸钾有机盐钻井液体系性能的影响，实验表明两套钻井液体系具有能够抗200 mg/L H2S、1000 mg/L CO2酸性气污染的能力，以及抗灰岩钻屑、地层盐水和各种盐相污染能力，且具有优越的流变性能、润滑性能、防腐蚀性能和储层保护效果，能够满足南帕斯酸性气田碳酸岩储层安全、快速、高效钻井。

In order to predict the volume of acid gas intruded into drilling fluid for drilling in sour gas field, the acid gas invaded volume and dosage of sulfide scavenger basic zinc carbonate and carbon dioxide scavenger calcium oxide were calculated on-site according to the geological parameters and drilling parameters. To evaluate the impact of acid gas pollution on the drilling fluid performance, an indoor evaluation method "gas perfusion by control cylinder pressure" was designed. And then the required perfusion pressure formulas for infusing different concentration of acid gas were developed according to ideal gas state equation. Using this experiment method we evaluated the influence of acid gas H2S and CO2 on clay-free NaCl brine drilling fluid system and solid-free potassium formate organic salt drilling fluid system that suit for carbonate reservoir of sour gas field. The results show that the two series drilling fluid system have the resistance capacity of 200 mg/L H2S, 1000 mg/L CO2 acid gas pollution, and have good ability of anti-lime stone cuttings, anti-formation brine water and various salt pollution tolerance. In addition, these two systems also have excellent rheological properties, lubricity, anti-corrosion and reservoir protective effects. The two series drilling fluid system can make sure the sour gas field carbonate reservoir safe, fast and efficient drilling.