Features Low Permeability Fractured Reservoirs Deep Profile Technology Research,

After injecting water of the fractured reservoir, the water crosses in easily through the fracture and most of the main facture which can be used for infiltrating is full of water, and the wells along the fracture are flooding. But the other fracture and the matrix are still saturated with high oil content. So it is a main problem how to blank off the high permeability zone effectively and enhance the oil recovery of fractured reservoir. This paper bases on the control profile problem of low temperature and low permeability fracture reservoir in Pingbei oil field, investigates the binary cross-linking gelation technology, the main content are:(1) Investigating the gel-forming performance of the primary cross-linking gelation system by taking activated organic chromium YJ05 as primary cross linking agent,researching the influence on the gel-forming performance by the different polymer molecular weight and concentration of YJ05.The results show:the higher the molecular weight and concentration are,the greater the intensity of the primary cross-linking gelation is,the lower the concentration of YJ05 is,the harder the gel forms in two hours.So for the high molecular weight polymer gelation system,the appropriate polymer concentration range is 0.15%-0.3% and the primary ratio of polymerization and crosslinking is 20:1-25:1;for the low molecular weight polymer gelation system, he appropriate polymer concentration range is 0.6-0.8% and the primary ratio of polymerization and crosslinking is 25:1-35:1.(2) Choosing the organic JF09 as primary cross-linking agent and researching the influence on the gel-forming performance by the different polymer molecular weight and concentration of JF09.The results show:,the appropriate concentration range of JF09 is 0.05%-0.1% and the appropriate concentration of high molecular weight polymer is 0.2%-0.4% which of low molecular weight polymer is 0.6%-0.8%.(3) Resepectively researching the rheological property and shearing resistance of the primary cross linking gelation system made by YJ05 and organic JF09.The results show:both system are the typical pseudoplastic fluid. After shearing half an hour with the shear velocity of 170S^-1 ,they keeps the viscosity at 78%-94% and has a good shearing resistance.(4) By taking YJ05 as primary cross linking agentl,investigating the gel performance of the second crosslinkling gelation system of organic chromium and compound crosslinking separately.The results show: in second organic chromium gelation system,the gelation time of KYPAM is 10h-6d and the gelation intensity range is C-D; When the concentration of the solution of HPAM with 4 millions molecular weight is 0.6%-0.8%, the appropriate primary ratio of polymerization and crosslinking is 30:l-70:land second ratio is 8:1-12:1,and it can form controllable gelation with 5-7d gel forming time and E-G intensity range; in the second crosslinking gelation system, the intensity range of high molecular weight system is E-G and the gel forming time is 5-10d ,the range of low molecular weight system is G and the gel forming time is 4-10d.(5) Selecting a low temperature accelerant and by taking YJ05 as primary cross linking agent, researching the gelation performance of the second phenolic aldehyde gelation system. The results show: the appropriate amount of the accelerant for high molecular weight system with the concentration of 0.2% is 8-14 mg/L and the intensity range after gel forming is D-E; when the accelerant amount for the low molecular weight system with the concentration of 0.6% is 5-200 mg/L, it can form gelation with the forming time of 11-22d and the intensity range of the gelation is D-F.(6) By taking JF09 as primary crosslinking agent, investigating the influence on the second phenolic aldehyde gelation system gel forming performance by the polymer concentration and concentration of JF09. The results show: when the high molecular weight polymer concentration is 0.2%-0.4% and the amount of JF09 is 0.01%-0.1%, it can form the binary gelation with l-7d gel forming time and C-F intensity range; when the low molecular weight polymer concentration is 0.6%-1.0% and the amount of JF09 is 0.05%-0.1%, it can form the gelation with 5-10d gel forming time and B intensity range.(7) Researching the adaptiveness of YJ05 and JF09 two king primary crosslinking gelation system and the formation water of Pingbei oil field. The results show: for the YJ05 primary crosslinking gelation system made by high molecular weight polymer, the appropriate polymer concentration is 0.2%-0.3%,the primary ratio of polymerization and crosslinking is 20:1-25:1; for the JF09 primary crosslinking gelation system, the appropriate high molecular weight polymer concentration is 0.3%-0.5%, the concentration of 4 millions low molecular weight polymer is 0.8%-1.0% and the amount of JF09 is 0.05%-0.1%. The appropriate temperature for the cross linking agent is 30-40℃.(8) Preparing the polymer solution by using simulated formation water of Pingbei oil field, by taking JF09 as primary cross linking agent,researching the gel forming performance of the second phenolic aldehyde gelation system. The results show: the gel performance of high molecular weight is and the appropriate concentration of polymer solution and cross linking agent are 0.3%-0.5% and 0.05%-0.1%.(9) Preparing the polymer solution by using injecting water of Pingbei oil field, by taking YJ05 as primary cross linking agent, researching gel forming performance of organic chromium and phenolic aldehyde second crosslinking gelation system. The results show: organic chromium system start to flocculate and the phenolic aldehyde system has a good suitability. When the polymer concentration is 0.2%,the primary ratio of polymerization and crosslinking is 20:1 and the amout of accelerant is 100mg/L, it can form the gelation with 9d gel forming time and the viscosity is 4200 mPa.s.(10) Through core flow experiment, researching the injectivity and the damage performance to basement of the primary crosslinking gelation system and the ability to break pressure gradient and anti-flooding performance of binary crosslinkling gelation system. The results show: the primary crosslinking gelation system has good injectivity and the forming of the primary crosslinking gelarion can reduce the filtration of the system in fracture. For the binary crosslinkling gelation systemthe, after scouring 40PV, plugging rate still remains over 90%. So this system has good performance to prevent breaking through.All of the experiment results show: the binary crosslinking gelation system can satisfy the profile control needs for the low temperature, low permeability and fracture oil field of Pingbei. The binary gel forming is the more appropriate controlling water technology for fracture reservoir and the research results have reference and application value.