The Study On Heavy Oil Profile Control Technology Of Block H In Steam Drive Reservoirs

Block H is a typical heavy oil reservoir.The key factors affecting the extent of crude oil exploitation in the block are the heterogeneity of reservoir,the change of permeability,the difference of fluidity ratio,the saturation of crude oil,well spacing,and the inclination of reservoir.The main reason for this phenomenon is the heterogeneity existing in inner and outer layers and the superfluous phenomenon of steam generated during steam injection.During thermal recovery,the injected high-temperature steam is low in density and protrudes along the top of the reservoir or high-permeability channels.The high-permeability layer is a strong suction layer,the low-permeability layer is a weak suction layer,and even no steam is absorbed.The steam suction profile is not uniform in the longitudinal direction,the temperature field distributed unevenly,and the steam channel is generated after steam injection.The steam sag is serious and the steam flooding effect is greatly reduced,which has severely restricted the effective development of heavy oil fields.At present,there is an urgent need to find effective development techniques to solve the current low-cost,low-efficiency,hard-to-explore,and low-recovery development conditions for heavy oil reservoirs.This paper aims at the basic status of heavy oil reservoirs in Block H.Studying the rheological properties,sealing performance and profile control performance of resin,polymer gel,verse resin and gel slug combinations through indoor experiments and research,respectively.The optimal profile control system are preferably the resin and gel slug combinations,and evaluate the thermal stability and optimize the injection parameters.The results of laboratory experiments show that the plugging rates of gel and resin slugs after 60 days aging at 180°C and 280°C are 60.74% and 54.34%,respectively.And they have good thermal stability;the earlier the injection time of resin and gel slug combinations,the higher the increased pressure,expanded volume effect and plugging effect are;the optimal injection volume of the gel and resin slug combination is 0.3PV.At the steam drive of 280°C,the final recovery factor can reach 82.75% when the water content is 30%.The gel and resin slug combinations can play a good role in increasing oil,laying the foundation for the steam drive profile control pilot test of this oil field and it has great significance for the development of heavy oil reservoirs and the improvement of oil recovery ratio.