Research On Profile Control By Chemical Agent Of Niuxintuo Oil Field For Enhancing Heavy Oil Recovery

Niuxintuo is an oil field of high oil viscosity and high wax content, the oil flow ratio greater difference, together with high reservoir hetergeneity and low porosity and low permeability. At present, it has entered into the yield rapid declining stage with high water-cut stage(above 70%), flooded is more serious especially for the sinking department and close mining areas which integral water content is above 75%. The measures taken before such as fracturing, profile control and the separated injection cannot stabilize oil production and controlling water cut. Consequently, the development of it becomes more difficult, a new low cost and high efficiency displacement technology is badly needed to be studied in order to improve injected water sweep volume and injected water sweep efficiency in the Niuxintuo oil field, as well as to improve the effect Niuxintuo oil formation development, in this way, we will achieve the target by further stabilizing oil production and controlling water cut to boost the recovery of Niuxintuo oil formation, as well as being a technological support for the sound progress of Niuxintuo reservoir.This project uses the laboratory physics analog testing manner which is based on the fine geology model of Niuxintuo oil field natural rock, respectively uses the manners of polymer flooding and the polymer/surfactant binary complex flooding to carry on the displacement experiment, so as to select the best displacement system suited to Niuxintuo oil field through investigating the outcome of these displacement systems.The numerical simulation method is adopted in this article to establish the fine geology model of the oil layers ranged from N1 to N7 in the Niuxintuo oil field. Depending on the water flooding history matching, we accomplished the water flooding forecast of T33-35 well-group and the whole areas, as well as the best selection of the adjustable flooding parameters and the slug injection pattern. The selection of adjustable flooding parameters including polymer molecular weight, the dosage of polymer, the solution concentration, injection speed and the time of slug injection. Use this manner to come into being the best displacement measure for Niuxintuo oil field which had improved about ten percent of the crude oil recovery in the Niuxintuo oil field depending on the water flooding.