Laboratory Research On Response Discipline Of Polymer Flooding In Heterogeneous Reservoir

Area of the Bohai Sea oil field reservoir is deposited on land, such high permeability oil reservoirs, more serious non-homogeneous, high viscosity of crude oil,water injection recovery is not high, enhanced oil recovery polymer flooding the potential is huge. Oilfield for the nature of the polymer flooding oil field development as an important means and methods. As a mature tertiary oil recovery technology,has been applied to a smooth sea oil field, in the application process required for the optimization and selection of parameters. In this paper, the development of domestic and international status of the polymer, offshore oil development and production characteristics of the parameters of the polymer enhanced oil recovery, including polymer injection timing, concentration, such as polymer injection slug.Physical simulation experiments carried out in the room, through experiments with polymer injection timing advance, the ultimate recovery increase, mainly due to the moisture content is not high bets together, crude oil in porous media more easily re-enrichment, and at this time porous polymer flooding in the water for the dilution effect for the system is not yet clear, has little effect on the ultimate recovery. Water flooding late in porous media water as continuous phase, polymer injection at this time, the water in porous media have a leading edge of polymer flooding dilution effect, and the remaining oil in non-continuous phase of polymer flooding is difficult to gather and development results; total water injection rate decrease, taking into account the useful life of offshore platforms preferred polymer injection at a reasonable time. Non-homogeneous rectangular cores, with the injection of hydrophobically associating water-soluble polymer advance the timing of the polymer, core injection pressure and pressure gradient both an increase in the case, the increase in pressure comes mainly from the viscous force model, therefore, proposed water polymer injection after a period of time development. Optimization of the polymer concentration from the experimental results, the increase with the concentration level of recovery increased, but the concentration of 1750mg / L, the recovery percent rate of increase has slowed down; Note the higher polymer concentration, water content decreased rate of major ; from the injection pressure to see, hydrophobically associating water-soluble polymer injection process, with the increase in the number of PV into the pressure increases, and with the increasing concentration of pressure increase. For water flooding water 0% (0PV) slug of polymer injection for optimal results, the amount of polymer equal to the total recovery under the conditions: (low + high) programs "(low + middle + high) programs" (high + middle + low) programs "(high + middle) program. The first program of low water slug harvest program in the former than the high slug short, but the program low-slug is better than the previous high slug the former program.