基于压力传递的钻井液纳米封堵剂研究与应用  

Study and Application of a Drilling Fluid Plugging Agent Based on Pressure Transfer Inhibition

作　　者：刘洋洋 邓明毅 谢刚 赵洋 

机构地区：[1]西南石油大学石油与天然气工程学院.油气藏地质及开发工程国家重点实验室,成都610500

出　　处：《钻井液与完井液》2017年第6期24-28,34,共6页Drilling Fluid & Completion Fluid

基　　金：国家自然科学基金重点项目(51574202)

摘　　要：针对南堡油田泥页岩地层孔隙尺寸为纳微米级,传统的微米级以上的固相颗粒难以实现有效封堵这一问题,选用纳米级钻井液封堵剂FT-3000、HLFD-1及环境友好型可变形聚合物封堵剂Green seal,在室内展开研究,评价其对高温高压滤失、砂盘滤失及泥饼承压能力的影响,并针对南堡油田所选岩心进行孔隙/裂缝封堵前后渗透率变化情况、压力传递及膜效率测试分析。结果表明用Green seal作封堵剂的钻井液,高温高压滤失量为17 m L,砂盘滤失量为13.8 m L,均为最小值,且其能有效提高泥饼承压能力至大于8 MPa,孔隙/裂缝封堵前后渗透率分析显示其封堵效果最佳,有效减缓了压力传递,膜效率为0.099 0,最大。该封堵剂在NP36-3652和NP36-3701井进行了应用,应用井井壁稳定、井径规则、渗透率恢复值高、滤液侵入量低,实现了泥页岩地层井壁稳定、储层保护的多重目的。The size distribution of pores in shale formations in Nanpu oilfield is in a level of micrometers or even nanometers. Conventional micrometer-sized solid particulate plugging agents used in water base drilling fluids are unable to effectively plug these pores. Laboratory experiments have been conducted with several nanometer-sized particulate plugging agents, such as FT-3000, HLFD-1 and Green Seal, to ascertain the effects of type and concentration of these plugging agents on HTHP filter loss, filtration through sand disc, pressure bearing capacity of mud cakes, and their performance in plugging nanometer-sized pores. Experiments have also been done on core samples taken from Nanpu oilfield to test the changes in core permeability before and after plugging of cores, pressure transfer and membrane efficiency. The experimental results showed that Green Seal had HTHP filter loss of 17 m L and filter loss through sand disc of 13.8 m L, the minimum values among the three plugging agents. With Green Seal, the pressure bearing capacity of mud cakes was increased to 8 MPa or even higher. Analyses of permeability of the cores before and after plugging experiments indicated that Green Seal had the best efficiency in pore plugging, effectively inhibiting pressure transfer. Membrane efficiency of Green Seal was 0.0990, the highest value among the three plugging agents. These experiments have proved that Green Seal, an environmentally friendly deformable plugging agent, is the best plugging agent evaluated. Green Seal has been applied on the well Nanpu36-3652 and the well Nanpu36-3701. The borehole wall was stable, and gauge holes were obtained. Recovery of permeability was high and filtrate invasion was low, realizing the multiple goals of stabilizing shale borehole and protecting reservoir formations from damaging.

关 键 词：压力传递 纳米封堵剂 滤失量 承压能力 渗透率 膜效率 

分 类 号：TE254.4[石油与天然气工程—油气井工程]