CAJ | 학술논문

采用前置液有效驱替油基钻井液是提高页岩气井固井质量的关键，表面活性剂则是决定前置液驱替效果的关键。目前，单纯以清洗效率为指标考虑工程性能来优选表面活性剂，工作量大且有一定的盲目性。因此，开展了基于表面活性剂特性的优选方法研究：①确定了清洗效率较高的表面活性剂离子类型和H LB值范围；②确定润湿渗透柴油基钻井液表面所需的临界表面张力γc ；③从表面活性剂表面张力和临界胶束浓度（CM C值）进行优选；④将材料研究与工程模拟评价相结合，最终确定一套适用于柴油基钻井液的前置液表面活性剂优选方法。实验结果表明，适用于柴油基钻井液的前置液用表面活性剂应满足以下特性：①应选用非离子或阴离子表面活性剂，且 H LB值应在12～15；②表面活性剂的较优加量应接近或大于表面活性剂的临界胶束浓度；③表面活性剂的γlg （溶液表面张力）应小于或接近润湿柴油基钻井液表面的γc （临界表面张力为25～27 m N／m ），此时，前置液的清洗效率较高。该方法可为表面活性剂的优选提供指导，有助于提高页岩气井固井质量。
채용전치액유효구체유기찬정액시제고혈암기정고정질량적관건，표면활성제칙시결정전치액구체효과적관건。목전，단순이청세효솔위지표고필공정성능래우선표면활성제，공작량대차유일정적맹목성。인차，개전료기우표면활성제특성적우선방법연구：①학정료청세효솔교고적표면활성제리자류형화H LB치범위；②학정윤습삼투시유기찬정액표면소수적림계표면장력γc ；③종표면활성제표면장력화림계효속농도（CM C치）진행우선；④장재료연구여공정모의평개상결합，최종학정일투괄용우시유기찬정액적전치액표면활성제우선방법。실험결과표명，괄용우시유기찬정액적전치액용표면활성제응만족이하특성：①응선용비리자혹음리자표면활성제，차 H LB치응재12～15；②표면활성제적교우가량응접근혹대우표면활성제적림계효속농도；③표면활성제적γlg （용액표면장력）응소우혹접근윤습시유기찬정액표면적γc （림계표면장력위25～27 m N／m ），차시，전치액적청세효솔교고。해방법가위표면활성제적우선제공지도，유조우제고혈암기정고정질량。
Preflush effective displacing oil‐base drilling fluid is the key to improve the cement quali‐ty of shale gas ,and surfactant is the key to decide the displacing effective of preflush .Currently ,op‐timizing surfactant only by cleaning efficiency as index to consider engineering performance is a heavy workload and has certain blindness .Therefore ,researches of optimization method depending on sur‐factant properties were carried out .Firstly ,the ion type and HLB value extent of surfactants with context higher cleaning efficiency were determined .Secondly ,the critical surface tension γc required by surface of wetting and penetrating diesel fuel based drilling fluid were ensured .Thirdly ,the sur‐factants were optimized by combining surface tension of surfactant with CMC values .Fourthly ,com‐bining the material research with engineering evaluation ,a set of optimization method suitable for pre‐ flush surfactants of diesel fuel base drilling fluid was determined .Experimental results showed that preflush surfactants of diesel fuel base drilling fluid should meet the following characteristics :①non-ionic/anionic surfactants should be used ,and the HLB value should be 12~15 ;②optimum dosages of the surfactant should be close to or over the critical micelle concentration of the surfactant ;③the sur‐face tension γlg of surfactant should be less than or close to the soaking surfaces of oil‐based drilling fluid γc (the critical surface tension=25~27 mN/m) ,and the cleaning efficiency of preflush is higher . This method can provide guidance for optimization of surfactants ,and help to improve the cementing quality of shale gas well .