防砂充填带封隔堵剂的筛选与初评实验

Selection and Preliminary Test for Blocking Agent at the Sand Control Section

渤海油田普遍采用大段充填防砂完井,为了进一步提高注水效果,需要把大段防砂段的充填带进行封隔,进一步细分层系,便于实施精细分层注水。采用化学封隔堵剂是比较可行的、成本较低的方法,为此从强度和触变特性出发,筛选了3种较为主流的化学封隔堵剂进行对比分析,并通过实验验证,环空化学封隔器比较适合渤海油田的完井方式。从温度、矿化度、剪切速率、强度4个因素考虑,对筛选出的环空化学封隔器进行了进一步的考察。结果表明:环空化学封隔器在60~110℃均可固化,固化时间在2 h以上,其固化特点基本不受矿化度的影响,且其具有良好的抗剪切能力,通过模拟实验,其强度可达4 MPa·m-1,符合渤海油田的使用条件。

Long packed section for well completion is widely used in Bohai oilfield.To improve the water injection effect,it is necessary to isolate the long packed section,so as to do the separate minelayer injection.The chemical blocking agent is a viable method to solve the problem with low cost.In this paper,based on strength and thixotropy,3 main kinds of blocking agents were compared and screened out.Annular chemical packer was chosen for the well completion mode through the test.From four aspects of temperature,mineralization,shear rate and strength,the screened annulus chemical packer was further investigated.The results showed that the annular chemical packer could solidify between 60℃to 110℃,and the solidifying time was more than 2 h.The solidifying capacity was not affected by the salinity,and it had well shear resistance.The strength reached 4 MPa·m-1 in the simulation test.So the annular chemical packer is suitable for the service condition of Bohai oilfield.