Bohai Oilfield The J3 Well District Associating Polymer Flooding Enhanced Oil Recovery Pilot Test Study

Polymer flooding, as one of the most important EOR technologies, has been applied industrially to the shore oilfield, but it's still in the beginning stage in the offshore oilfield. In order to apply the technique of polymer flooding to the offshore oilfield, some problems( the big well spacing, the high viscosity of the subterranean oil, the thickness of the reservoir, the lack of the fresh water, the production platform space is narrow and the service life is limited) must be faced. As long as the polymer has the good properties that are the high-effective viscosity, the good tolerance of temperature and /or salinity, the shear resistance, the long-term stability and the function of the fast solvency, it is possible to apply the polymer flooding to the offshore oilfield.According to the characteristics of the offshore oilfield, this essay chooses the hydrophobically associating water-soluble polymer which is of good properties as the polymerized solute. The capability of the HAWSP was studied in experiment at the reservoir of J3 block. The results indicate that HAWSP has good displacement efficiency at the actual reservoir. Based on the lab experiment, FAPMS is used as a simulator to optimize HAWSP flooding injection procedure, slug size and chemical concentration. According to the result of the simulation, the optimal project of the polymer flooding is recommended. It is that the 3000mg/L preplug size is 0.012PV and that the 1750mg/L main plug size is 0.25PV. The project can enhance 9.207%OOIP in the crude oil recovery than water flooding. The increased quantity of the crude oil is 54279t, and the increased oil quantity per ton of HAWSP is 128.8t. The integrated index is 1185.9. In addition, it is preliminary appraised in technology and economics about the choosed polymer flooding. The results indicate that it is economic and effective of carrying on HAWSP flooding in J3 block in Bohai oilfield. These days, the Pilot field test is being carried on. The total water in the test field is decreased from 57% before polymer flooding to 48% at present. The quantity of the oil production is increased from 367 to 417 ton per day. The initial test results indicate that the polymer flooding experiment to enhance oil recovery is successful, which has the obvious results of increasing the oil production and decreasing the water production. The success implies that the research reached the anticipant purpose. It can provide a dependable warranty of technology and economy on a large scale polymer flooding in future and has probe into an effective way of EOR in the offshore oilfield.