Development And Application Of Organic Crosslinked Blocking Agent

In this paper, the best formulation of the organic compound cross-linking agent which takes the partially hydrolyzed polyacrylamide as the main chemical and take the organic Cr3+ and phenolic aldehyde as cross-linker was selected, according to the technical problems of profile modification and water shut-off encountered in low penetrability and fracture-type reservoir in KeLaMaYi oil field. Thus, on the reservoir conditions of the seventh middle area of JiaMuHe and eighth area of XiaWuErHeZu, the qualities of blocking agent such as gelatification time, the gel strength, the salt resistance, the temperature resistance, the stability, the compressive strength, the selection of injection, the improvement ratio of water entry profile and the sweeping efficiency were evaluated. The experimental results indicated that this blocking agent have following advantages: its gelatification time can be controlled and adjusted between 2-72 hours, its compressive strength can reach from 26 MPa/m to 61 MPa/m, and its stability is perfect within a long time.Furthermore, the experiment research was conducted to study its organic compound crosslink mechanism. The research results indicated that the first cross-linking between the HPAM and Cr3+ in ground condition was propitious to reduce leaking of blocking agent in oil layer, and the second crosslink action between acylamino of HPAM and organic phenolic aldehyde can form the high intensity gel and it can endure high temperature.Based on these research works, in October 2001 this blocking agent was applied in XiaWuErHe 85079 well pattern and JiaMuHe 7511, 7515 wells in KeLaMaYi oil field. By the end of October 2002, it has increased oil production accumulated to 2065 tons, acquired notable effect.