Optimization Of Advanced Water Injection Parameters In Hujianshan Block Of Changqing Oilfield

The Chang 6 Reservoir block in Block L of Hujianshan Oilfield has poor physical properties,low production,and lack of natural energy.The formation pressure caused by the pressure-sensitive effect drops rapidly,and the pressure that can be hardly recovered.Development is difficult.The advanced water injection technology injects a certain amount of water from the water injection well before the oil and gas production,so as to effectively compensate for the lack of natural energy in the reservoir.Using this technology to develop the block can keep the formation pressure stable in the block.It can also improve the long-term stable production level of the reservoir,and finally solve the development problem of Chang 6reservoir in L area of Hujianshan Oilfield.Based on this article,the reservoir numerical simulation technology was used to study,analyze and optimize the advanced waterflooding development plan of Chang 6 reservoir in L area of Hujianshan Oilfield.Analyzing and predicting the development effects under different schemes provides advanced water injection development used by the block with reliable theoretical guidance,which maximizes economic benefits and improves the oil and gas recovery rate of the block.First of all,based on the geological data,this paper summarizes and analyzes the geological characteristics of the Chang 6 reservoir in the L area of Hujianshan Oilfield,and then establishes the geological model of the block after analysing geological characteristics.Using geological modeling combined with reservoir engineering and numerical simulation methods,this paper studies and optimizes the reasonable parameters of advanced water injection in the study area.Finally,combined with different optimization schemes,this paper predicts and analyzes the production capacity of the block after 20 years.The results show that:(1)The average permeability of the reservoir in the L area of Hujianshan is 0.841mD.The pressure coefficient is between 0.7-0.8.The viscosity of the crude oil is 5.17mPa.s.The above-mentioned statistics meet the conditions for implementing advanced water injection technology.The implementation of this technology in the L zone can achieve a good production increase effect;(2)Through geological modeling and numerical simulation methods,the reasonable flow pressure of the oil well in the initial stage of development is finally determined to be 2.91MPa,and the reasonable bottom hole flow pressure is between 2.6-3.2MPa.The reasonable pressure maintenance level is 81.0%.The water injection pressure limit does not exceed 21.97MPa.The reasonable injection volume is8.433m~3.The reasonable water injection intensity is 2.63m~3/d·m.The advanced water injection time is 374 days;(3)The first plan is to use the current actual development status as the basic plan;the second plan is to improve the injection and production of 43 wells,the third plan is to treat 24 wells with low productivity and low efficiency,and the fourth plan is to optimize the development limit.After 20 years of production capacity prediction for these three schemes,the cumulative oil increase can be 49,000 tons,74,000 tons and 117,000 tons respectively.The fourth scheme has the best effect.