塔河高温高盐缝洞型油藏堵剂性能评价

Static Performance Evaluation of Plugging Agent in High-temperature and High-salinity Tahe Fractured-vuggy Reservoir

塔河缝洞型油藏高含水问题日益严重,堵水是解决高含水问题的有效技术之一。受高温高盐及缝洞特征影响,尽管凝胶堵剂种类多,但还未形成满足塔河缝洞型高温高盐油藏的凝胶堵剂。为此,研究了淀粉凝胶、耐温冻胶和高温凝胶3种类型堵剂在高温高盐条件下的成胶时间和成胶强度,评价了堵剂的关键性能指标,考察了堵剂的长期热盐稳定性。结果表明:淀粉凝胶的成胶时间为1~3 h,成胶强度达到E级;耐温冻胶的成胶时间为4~7 h,成胶强度为C~D级;高温凝胶的成胶时间为2~5 h,成胶强度达到I级;3种堵剂在高温下的长期稳定性均需进一步提升。

The problem of high water cut in Tahe fracture-cave reservoir is becoming more and more serious,and water plugging is one of the effective technologies to solve the problem.Affected by high temperature,high salinity and fracture and cave characteristics,although there are many types of gel plugging agents on site,a mature gel plugging agent for water plugging in Tahe fracture and cave reservoir has not yet been formed.Therefore,the gel-forming time and gel-forming strength of starch gel,temperature-resistant gel and high-temperature gel under high temperature and high salt conditions were studied,the key performance indexes of the plugging agent were evaluated,and the long-term hot-salt stability of the plugging agent was investigated.The results showed that the gel-forming time of starch gel was 1~3 h,and the gel-forming strength reached E grade;The gel-forming time of the temperature-resistant gel was 4~7 h,and the gel-forming strength was C~D;The gelation time of high-temperature gel was 2~5 h,and the gelation strength reached grade I;The long-term stability of the three plugging agents at high temperature needs to be further improved.