连续动态多重光散射法评价高密度油基钻井液稳定性  

Dynamic Evaluation of Stability of High Density Oil-based Drilling Fluid by Multiple Light Scattering Method

作　　者：马超 苏超 周超 潘蕾茗 徐生江[2] 叶成[2] 孙晓瑞[2] MA Chao;SU Chao;ZHOU Chao;PAN Leiming;XUShenggjiang;YE Cheng;SUN Xiaorui(Key Laboratory of Hubei Province for Oil and Gas Drilling and Production Engineering,Yangtze University,Wuhan 430100,Hubei,China;Engineering Research Institute,Xinjiang Oilfield Branch of CNPC,Karamay 834000,Xinjiang,China)

机构地区：[1]长江大学石油工程学院油气钻采工程湖北省重点实验室,湖北武汉430100 [2]中国石油天然气股份有限公司新疆油田公司工程技术研究院,新疆克拉玛依834000

出　　处：《西安石油大学学报（自然科学版）》2018年第6期112-117,共6页Journal of Xi’an Shiyou University（Natural Science Edition）

基　　金：国家科技重大专项"高含硫气藏安全高效开发技术"(2011ZX05017-002)子课题"超深水平井钻井液技术"(2011ZX05017-002-HZ07);中国石油新疆油田公司项目"准噶尔盆地南缘膏泥岩;厚层泥岩钻井液技术研究"(XJYT-gcjsyjy-2016-JS-223)

摘　　要：采用多重光散射仪(AGS)持续测试高密度油基钻井液静置不同时间的背散射光强度的变化规律,分析油基钻井液在不同时间内的综合稳定性。研究了密度、NaCl质量分数、CaCl2质量分数及CaSO4污染对油基钻井液稳定性的影响。实验结果表明:在相同密度下,高密度油基钻井液的不稳定是由于加重剂等固相粒子沉降引起样品池的顶部有清液层析出,底部有一定团聚沉淀形成;随着密度的增加(2. 0～2. 6 g/cm3),钻井液的综合稳定性增强,说明加重剂固相的增加并不是导致钻井液不稳定的主要原因,与钻井液中的乳化润湿体系有很大的关系。NaCl质量分数增加(3%～12%)对钻井液稳定性影响不大; CaCl2质量分数增加(5%～25%),钻井液体系的稳定性增加; CaSO4浓度的增加对油基钻井液的稳定性影响较为复杂,在高浓度(15%)和低浓度(3%～10%)钻井液稳定性均会降低,质量分数为12%时钻井液的稳定性最好。The backscattered light intensity of high density oil-based drilling fluid at different static time was measured using multiple light scattering instrument （AGS）, and the comprehensive stability of oil-based drilling fluid at different static time was analyzed. The experimental results show that：at the same density, the instability of high-density oil-based drilling fluid is due to the formation of the clear liquid layer at the top of the drilling fluid sample pool and the agglomeration precipitation at the bottom of the sample pool caused by the sedimentation of solid particles such as weighting agent ; with the increase of drilling fluid density （2.0 - 2.6 g/cm^3 ） , the comprehensive stability of the drilling fluid is better,which shows that the increase of solid phase weighting agent is not the main cause of drilling fluid instability, and the instability is greatly related to the emulsifying wetting system in drilling fluid. The increase of NaCl mass fraction （3% - - 12% ） has little effect on the stability of the drilling fluid;the increase of CaCl2 mass fraction （5% - -25% ） will improve the stability of the drilling fluid system. The relationship between the stability of high density oil-based drilling fluid and CaSO4 concentration is very complicated. The high mass fraction （15%） and low mass fraction （3% - 10% ） of CaSO4 will reduce the stability of the drilling fluid, and the stability of the drilling fluid is the best when the mass fraction of CaSO4 is 12%.

关 键 词：高密度油基钻井液 稳定性 加重剂 多重光散射仪 

分 类 号：TE39[石油与天然气工程—油气田开发工程]