煤层气钻探低密度钻井液物/化协同降滤失研究  

Study on physical and chemical coordinative depressing filter loss of low density drilling fluid for coalbed methane drilling exploration

作　　者：朱金勇[1] 侯淑鹏 陈礼仪[1] 王胜[1] 邹杰[2] 宋佳奇 

机构地区：[1]成都理工大学地质灾害防治与地质环境保护国家重点实验室,四川成都610059 [2]四川省川建勘察设计院,四川成都610017 [3]四川西南交大土木工程设计有限公司,四川成都610031

出　　处：《煤炭科学技术》2016年第9期122-126,160,共6页Coal Science and Technology

基　　金：国家自然科学基金资助项目(41272331;51204027);中国地质调查局资助项目(12120113017300);地质灾害防治与地质环境保护国家重点实验室资助项目(SKLGP2012Z007)

摘　　要：针对低压力系数孔隙裂隙煤岩储气层钻进过程中的储层损害及孔壁不稳定问题,采用微观分析和试验研究相结合的方法,开展了拥有物/化协同降滤失性能的钻井液体系的研制。分别对由超细惰性材料、化学添加剂配制的钻井液进行API失水试验,并采用扫描电镜分析手段对所形成的泥皮进行微观形貌分析。通过正交试验研制出拥有物/化协同降滤失性能的钻井液优化配方,采用扫描电镜分析手段对其泥皮进行微观形貌分析及性能评价。通过API试验、扫描电镜分析得到了空心玻璃微珠颗粒在泥皮中搭桥形成微米级孔隙发育的空间结构,使基浆滤失量增加;纳米二氧化硅在泥皮中形成的空间结构松散,孔隙率大,导致滤失量随纳米二氧化硅剂量的增加由24 m L迅速增加至50m L。而降滤失剂泥皮光滑致密,能使基浆滤失量由24 m L降低至10 m L左右。最终通过正交试验优化了含超细惰性材料的钻井液配方。研究结果对于揭示超细惰性材料与黏土矿物及降滤失剂的相互作用机理以及低压力系数孔隙裂隙煤岩储气层的快速钻进具有重要意义。According to the problem of the reservoir failure and the borehole wall instability occurred in the drilling process of the pore and crack coal and rock gas reservoir with low pressure coefficient,a micro-analysis and the experiment study combined method was applied to conduct the research and development on the drilling fluid system with the physical and chemical coordinative depressing filter loss performances. An API water loss test was conducted on the drilling fluid prepared with the ultra-fine inert materials and chemical additives and the means of the scanning electron microscopy analysis were applied to the morphology analysis on the mud cakes formed.The drilling fluid optimized formulation with the physical and chemical coordinative depressing filter loss performances was researched and developed with orthogonal experiment.The means of the scanning electron microscopy analysis were applied to the morphology analysis and the performance evaluation on the mud cakes. API experiment and scanning electron microscopy analysis revealed that hollow glass microsphere increased the filter loss of basic mud,due to its particles forming a space structure with developed micron pores by bridging in the mud cake. The filter loss rapidly increased from 24 m L to 50 m L with the increasing of nano-silica doses,due to nano-silica forming a loose spatial structure,which had the big porosity. However,the filter loss of filtrate reducers decreased from 24 m L to 10 m L by forming a smooth and compact mud cake. Finally,the drilling fluid formulation with ultrafine inert material was optimized by orthogonal test. The study achievements would have important significances to reveal the interaction mechanism between the ultra fine inert material and the clay mineral and the filtrate reducer,and to the rapid drilling of the coal and rock reservoir with low pressure coefficient pore and cracks.

关 键 词：降滤失 空心玻璃微珠 纳米二氧化硅 低压力系数 孔隙裂隙煤岩储气层 

分 类 号：TE254[石油与天然气工程—油气井工程]