大庆萨北油田采出污泥调剖剂研发及应用

Development and Pitol Test of Particulated Sludge Based Profile Modificator in North Saertu Oil Field

分析了取自大庆采油三厂一矿、二矿、联合站的含油污泥及其固相,含油污泥除含水、含油外,固相含量为37.34%～96.26%,固相颗粒外形不规则,粒径大于40目的占84%以上,主要为黏土矿物,90%以上为伊利石和高岭石。所研发的调剖剂为悬浮在聚合物污水溶液中的污泥固相颗粒,聚合物为M=2.5×107、水解度26.5%的大庆产HPAM,由沉降速率测定结果确定聚合物浓度为0.6～1.2g/L,污泥质量分数<6%。选择北4-8-丙水56井为调剖试验井,处理目的层为P11-2,有效厚度4m,处理厚度3m,设计分4个段塞注入调剖剂1.5×104m3,其中含聚合物13.3t,污泥固相435t(折合污泥1164t)。2008年8月21日起实施深部调剖,在51天内注入3个段塞共6526m3调剖剂,共利用含油污泥267.2t。注入期间注入压力迅速升高约1.5MPa后稳定在12.6～13.0MPa。5口连通油井(平均含水96.47%)中有4口含水平均下降1.4%,增油有效期110d,累计增油1135.2t。

The reservoir originated oily sludge taken from the 1st and 2nd production sectors and the gathering/treating plant in the 3rd Daqing production factory contained 37.34%—69.26% solids besides of water and oil; the sludge solids were mainly clay minerals,of which 〉90% was illite and kaolinite,and the clay particles were irregular in form and 〉84% particles was 〉40 mesh in size. The profile modificator（PM） developed was composed of sludge solids suspended in produced water solution of HPAM polymer of M=2.5×10^7 and HD=26.5%,in which the HPAM concentration was in range 0.6—1.2 g/L and the mass fraction of sludge solids was〈 6% as screened through sedimentation velocity measurements. The water injection well chosen for the indepth profile modification pilot（IPMP） was Bei-4-8-Bing-W56 at reservoir layer P11-2 of effective thickness 4 m and treatment thickness 3 m and it was designed to inject 1.5×10^4 m^3 PM in 4 slugs containing 13.3 t polymer and 435 t sludge solids （from 1164 t oily sludge）. The IPMP was started Aug 21,2008 and totally 6526 m3 PM was injected in 3 slugs in 51 days and 262.2 t of oily sludge was consumed. During PM injection the injecting pressure was fast raised by about 1.5 MPa and kept at a level 12.6—13.0 MPa. In 4 of the 5 oil wells connected with the injection well,the watercut was drop by 1.4% in average from average watercut of 96.47% and totally 1135.2 t oil was produced additionally in 110 days.