Experimental Study On Effect Evaluation Of Thin-layer Heavy Oil Horizontal-well Solvent-enhanced Steam Flooding(HW-SESF)

As the main means to enhance oil recovery in heavy oil reservoirs,steam flooding has been carried out on a large scale at home and abroad,with significant production increase effects.However,long-term studies have shown that steam flooding in thin-layer heavy oil reservoirs has serious problems such as severe heat loss in the top and bottom caprocks and small steam sweeping range.These problems seriously restrict the heat utilization of steam and the development of thin-layer heavy oil reservoirs.At home and abroad,research on thin-layer heavy oil reservoirs is in the ascendant.Many problems related to solvent improvement of displacement efficiency and improvement of steam chamber development are urgently needed.In this paper,a two-dimensional physical simulation model is designed based on a thin layer of heavy oil reservoir(A oilfield),and systematic experimental research and analysis are carried out.Using the two-dimensional sand-filling physical model simulation,the effects of different solvent and steam injection ratios on the displacement effect of solvent-assisted horizontal well steam flooding were studied.Secondly,the differences in the displacement effects of different types of solvent-assisted horizontal wells were discussed.Finally,the displacement effect of composite solvent assisted horizontal well steam flooding was studied.On the basis of physical simulation,the numerical simulation method of reservoir was used to compare and verify the conclusions of physical simulation experiments,and the migration laws of different solvents in steam chamber and the effects on temperature field,viscosity field and residual oil saturation field were analyzed.Regularity;At the same time,the difference analysis of different solvent recovery rates was carried out,and finally the understanding and evaluation of different kinds of solvents were formed.Through physical simulation and numerical simulation,the effects of solvent and steam injection ratio on the displacement effect were obtained.The effects of light,medium and heavy solvents and the displacement effects of three kinds of solvents were related.Under the understanding,a reasonable development strategy for thin-layer heavy oil solvent assisted horizontal well steam flooding was formed.The research results obtained in this paper provide the necessary technical support for the development of similar reservoirs and have important guiding significance for the actual mines.