| In the development of oil fields,chemical flooding has become an important means of greatly improving oil recovery.ASP flooding has a significant effect on recovery,but the alkali problem limits the promotion and application of ASP flooding.Binary compound flooding is gradually receiving attention,and the emulsification and interface effects of the binary complex system can improve effect of oil,but there are differences in the mechanism of the oil displacement in them.In view of the fact that the trial production of the Jinzhou 9-3 oilfield dual-component compound drive field is not obvious at present,the effects of emulsification and interface effects on the seepage characteristics of the binary composite system were studied separately,and the impact of the two on the enhanced oil recovery was analyzed.This will provide guidance for the optimization and improvement of the Jinzhou 9-3 oilfieldFirst,the HDS and polymer SNF3640C were used to screen the binary complex system with strong interfacial properties and strong emulsifying properties.Among them,the interfacial properties are selected by wettability and interfacial tension,and the emulsifying properties are selected by emulsification rate and emulsion stability.This paper adopts the method of adding the additive AlCl3·6H2O on the basis of the original binary compound system to obtain a binary composite system with strong interfacial properties and strong emulsifying properties.Finally,a binary system with strong interfacial properties for HDS 2000mg/L and SNF 3640C 1200mg/L binary system solution and a 20mg/L additive containing AlCl3.6H2O were obtained,and HDS 2000mg/L,SNF3640C is 1200mg/L strong emulsifying properties binary compound system.In order to compare the effects of emulsifying properties and interfacial activity on the seepage characteristics of binary composite systems,the non-steady state method was used to determine the relative permeability curves of water flooding,polymer flooding,and strong interfacial properties and strong emulsifying properties of binary composite systems.The following results were found:The relative permeability of the binary oil-water phase area was greater than that of water flooding.The water saturation at the isotonic point increased 11%and 13%,and the residual oil saturation point were all shifted to the right,and decreased 15.8%and 20.2%.And the two phase area was greater than polymer flooding and the residual oil saturation were decreased 8.2%and 12.6%respectively.For two kinds of binary composite systems,the relative permeability of the two phases of the strong interface performance system was higher than that of the strong emulsion performance system,and water saturation at the isotonic point increased 2%and the residual oil saturation point were relatively shifted to the right and decreased 4.4%.It showed that the strong interface performance system had a greater flow capacity than the strong emulsion performance system during flooding,and had a better displacement effect.Then microscopic measures were used to study the characteristics of seepage and the mechanism of the start of residual oil in the two kinds of binary composite systems,and compared the seepage process and displacement effect over time.It showed that the start of residual oil in the swept area was due to the strong interface performance system reducing the interfacial tension and changes the wettability.And the start of residual oil in the unswept area was due to the strong emulsion performance system emulsifying the entrapped oil droplets and played a major role in the plugging channel to expand sweep area.Compared with the strong emulsion performance system,the strong interface performance system had a stronger wetting effect and oil-water phase had a higher percolation capacity.The binary composite systems with strong interfacial properties and strong emulsifying properties could both improve the oil recovery of porous medium core.And with short action time,the oil displacement effect of the system with strong interfacial properties was better.But when the time was long enough,the oil displacement effect of the system with strong emulsifying properties had greater potential.And the system with strong emulsifying properties could further improve the oil displacement effect in Jinzhou 9-3 oilfield when the water cut was high. |
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