Optimization Of Nitrogen Assisted Steam Flooding Parameters In Heavy Oil Reservoirs

The viscosity of heavy oil reservoir is high,and the reservoir fluid is not mobile.With the development of steam flooding in the late development of heavy oil reservoir,the problems exposed in the process of development are becoming more and more obvious,the effect of mining has fallen sharply,and the characteristics such as adding formation energy,preventing steam overlying,expanding the range of steam wave and so on,can be used to improve the development effect and improve the recovery yield.Nitrogen can effectively improve the effect of steam heating,reduce the viscosity of heavy oil,and nitrogen is also cheaper.The development of auxiliary steam drive can reduce the development cost of oilfield.Nitrogen assisted steam drive is an improvement and improvement of steam flooding.After mixing with nitrogen and steam,the effect of steam flooding is strengthened.The oil viscosity of J230 well is high.After steam flooding,it has already entered the late stage of steam drive.Most of the oil wells have high water cut,low oil and gas,heavy gas channeling,large difference in production and poor mining effect on the plane.Based on the geological characteristics and development characteristics of J230 well area,this paper uses STARS software to make geological modeling and historical fitting for four representative well groups,and studies the distribution of residual oil in the block.Combined with the mechanism of nitrogen assisted steam drive,we determined the way of nitrogen injection assisted steam flooding to improve the recovery efficiency of the reservoir.The seven kinds of nitrogen auxiliary continuous steam flooding,nitrogen auxiliary intermittent steam flooding,nitrogen gas slug auxiliary steam flooding,nitrogen gas foam auxiliary steam flooding,nitrogen foam auxiliary steam flooding,nitrogen foam auxiliary intermittent steam flooding,nitrogen foam slug auxiliary steam flooding and nitrogen injection flooding are used in the numerical simulation method.The injection parameters of the development mode were studied and optimized respectively.By analyzing and comparing the development effects of different development methods,the optimum development mode of nitrogen foam assisted intermittent steam flooding was selected,and the sensitivity factors affecting the nitrogen foam assisted intermittent steam flooding were studied.Finally,the design plan is adjusted,and two development modes are designed for production prediction,and the best development plan suitable for the block is selected.