水平井蒸汽驱蒸汽腔均衡发育主控因素研究

Research on the main controlling factors for the balanced development of steam chambers in horizontal well steam drive

海上M区块为薄层稠油油藏,采用水平井蒸汽驱开发,蒸汽腔发育受到先期井网和后期优渗通道影响。为此,基于数值模拟法,以突进系数为评价指标,分析原油黏度、地层倾角、平面渗透率级差、注入温度、注汽速度、注入干度、采注比对水平井蒸汽驱蒸汽腔均衡发育的影响,基于分析结果引入变异系数S作为评价指标,以表征突进系数在研究范围内的敏感程度,研究表明,影响薄层稠油水平井蒸汽驱蒸汽腔均衡发育的主控因素为:采注比、注入干度、地层倾角,可根据各主控因素对蒸汽腔均衡发育的影响,对水平井蒸汽驱开发设计进行优化。

Offshore block M is a thin layer heavy oil reservoir,which is developed by horizontal well steam flooding.The development of steam cavity is affected by the early well pattern and the late superior permeability channel.Therefore,based on the numerical simulation method,the effects of crude oil viscosity,formation dip angle,plane permeability difference,steam injection temperature,steam injection speed,steam injection dryness and production/injection ratio on the equilibrium development of steam cavity in horizontal wells steam flooding were analyzed with the outburst coefficient as the evaluation index.Based on the analysis results,coefficient of variation S was introduced as the evaluation index to represent the sensitivity of the outburst coefficient within the study range.The results show that the main controlling factors affecting the equilibrium development of steam cavity in thin layer heavy oil horizontal wells steam flooding are production/injection ratio,injection dryness and formation dip angle.The development design of steam flooding in horizontal wells can be optimized according to the influence of each controlling factor on the equilibrium development of steam cavity.