The Adaptability Evaluation And Optimization Of Injection Production System Of Song700Well Area

Based on the analysis of core, logging data and experimental data, Song700well area hasconsidered that was delta sedimentary system, that has been divided into delta plain, front andprodelta subfacies. The average porosity of reservoir is8.105%, the average permeability is0.532×10-3μm2, the average original oil saturation is47.20%. Basically Song700well area isthe low porosity, low permeabilit, low saturation reservoir. The comprehensive moisturecontent is32.59%in Song700well area, and that period is inaqueous phase.The water flooding effect of Song700well area has been evaluated that Simultaneousinjection is the most appropriate water flooding regime based on the dynamic production data.The adaptability of different pattern has been demonstrated by the intensity of waterinjection, sweep coefficient, control degree of water flooding, oil recovery rate, well patternadjustment flexibility in Song700well area, and that row injection is the better mode. Thereasonable well pattern density has been demonstrated by using the Sher Cacho J formula,reasonable oil recovery rate, injection production balance method, Jascha, formula, productionmethod, analogy method six kinds, and the reasonable well spacing density has been28.39/km2, and the current well network density29.44/km2of Song700well area is morereasonable. The calculation of starting pressure gradient and its relationship to limit wellspacing has been analysised, and it has been thougt that the reasonable injection productionwell was165m. The average injection production well spacing is184m in Song700well area,and that is slightly higher by the ultimate injection production well spacing. The reasonableratio of oil wells and water wells has been1.53by using injection production balance principleand method of the liquid producing capacity maximization.The flowing pressure of producing well which can be set in0.9~1MPa, and wellheadpressure of water injection which can be set in6.76MPa, and reasonable formation pressurewhich is2.75MPahas been optimizated by analysis on the injection and production as a wholesystem. In the reasonable water injection pressure, daily injection rate can reach628.915m3/d,and that increased69.2%by daily water injection current of Song700well area and so theliquid production, oil production doubled. Through in-depth analysis of the oilfield dynamic,static data, waterflood development comprehensive evaluation indexes has been optimizated, and the adjustment suggestion, measures and methods has been put, which has become reliablebasis for improving the effect of water flooding and improving the ultimate recovery rate.