牙哈5凝析气藏开发方式优化

凝析气藏作为一种特殊的油气藏类型,由于特殊的流体相态特征决定了其开发难度要比一般油气藏复杂得多,开发中不仅要考虑天然气的采出程度,而且还要兼顾凝析油的采出程度.牙哈5气藏为富含凝析油气藏,通过组分数值模拟对不同的开采方式进行对比,得出采用衰竭、注水和注气3种开采方式的开发效果.注水和注气是为了保持地层压力,防止凝析油在地层内大量析出,从而提高凝析油的采收率.对比研究表明,注水和注气开采牙哈5凝析气田要优于衰竭式开采.对注水和注气两种开采方式而言,由于牙哈5气田储层自身的特点,在提高凝析油采出程度方面注气开采方式又要优于注水开采方式.预测结果表明,采用大井距注气开发方式对于延缓气窜可以起到一定作用,从而有利于提高注气效率,增加凝析油采出程度.

Optimization of development pattern of Yaha 5 condensate gas reservoir

As a special type, condensate gas reservoir is more difficult to develop than common reservoirs because of its special fluid phase state characteristics. Not only recovery degree of gas but also recovery degree of condensate oil should be considered. Yaha 5 is a small rich gas - condensate reservoir in Tarim. Through compositional simulation, this paper compares the application of depletion, waterflooding and gas injection to this reservoir. Water and gas injection is used to maintain reservoir pressure above dew point pressure and prevent condensate dropout in the reservoir. Simulation shows that water and gas injection is more effective than depletion. Reservoir characteristics determine that gas injection is more effective that water injection in producing Yaha 5 reservoir. Prediction shows that large well spacing gas injection can retard gas channeling, resulting in increasing gas injection efficiency and recovery degree of condensate oil.