双网络结构冻胶堵剂在高温高盐下的性能研究

Study on the performance of gel plugging agent with Dual network structure under high temperature and high salt

针对塔河油田高温、高盐等缝洞油藏堵水困难的技术难题,构建了双网络结构的冻胶堵剂体系。以N-(3-二甲胺丙基)甲基丙烯酰胺(DMAPMA)和氯乙酸钠(ClCH2COONa)为原料合成甜菜碱单体TCJ,与单体甲基丙烯酰氧乙基三甲基氯化铵(DMC)和N-(3-二甲氨基丙基)甲基丙烯酰胺(DMAPMA)共聚合成疏水缔合聚合物CDD。采用矿化度为22×10^(4)mg/L的实际地层水,以0.8%(AM/AMPS)聚合物FZ、1.2%酚醛交联剂、0.15%CDD和0.05%特种交联剂CN-10在130℃条件构建互穿双网络结构冻胶CDD-FZ。冻胶性能测试结果表明,双网络冻胶CDD-FZ,仅3 h就能成胶并且成胶强度为H级,最大屈服应力为326.42 Pa,突破压力为88.19MPa/m,30天脱水率1.14%,较传统单层网络结构冻胶具有更高的强度、耐盐性、耐温性和耐稀释性。该研究填补了塔河油田耐温抗盐高强度堵水冻胶的技术的空白,具备较好的实际应用前景。

Aiming at the technical problems of water plugging in fracture-vuggy reservoirs such as high temperature,high salt and high water cut in Tahe oilfield,a gel plugging agent system with interpenetrating double network structure was constructed.Betaine CMB was synthesized from N-(3-dimethylaminopropyl)methyl acrylamide(DMAPMA)and sodium chloroacetate(ClCH_(2)COONa).The hydrophobic associating polymer CDD was synthesized by copolymerization of methyl acryloxyethyltrimethylammonium chloride(DMC)and N-(3-dimethylaminopropyl)methyl acrylamide(DMAPMA).Using the actual formation water with salinity of 22×10^(4)mg/L,the cross-linking agent of 0.8%(AM/AMPS)polymer FZ,1.2%phenolic crosslinking agent,0.15%CDD and 0.05%CN-was used to construct the interpermeable double-network structure of the gel CDD-FZ at 130℃.The results of gel-performance test show that the dual-network gel-CDD-FZ can gel-form in only 3 hours and the gel-forming strength is H grade,the maximum yield stress is 326.42Pa,the breakthrough pressure is 88.19MPa/m,and the dehydration rate is 1.14%in 30 days.Compared with the single-layer network gel-form,it has higher strength,salt resistance,temperature resistance and dilution resistance.The research has filled the gap of high strength water plugging gel technology with high temperature and salt resistance in Tahe oilfield and has a good prospect of practical application.