板桥地区凝析油气藏气液两相渗流机理及水驱特征

Study on gas-liquid percolation mechanism and water flooding characteristic of condensate oil and gas reservoir in Banqiao area

板桥地区板2油组为典型的凝析油气藏,其流体渗流机理及水驱特征复杂,致使开发调整工作难度较大。通过开展气液两相渗流实验,认为伴有相变过程的气液两相流体随着流动状态和压力的变化而发生相变和相间质量传递,流体的挥发与气液流动速度、状态以及压力有一定的关系,压力降低有利于液体挥发产生气体。实验表明降压注水开采过程中,当压力低于临界饱和压力时,气泡成为原油流动的阻力,合适的注水时机为压力降到泡点压力的87%以上。此外,气体作用的强弱对剩余油的形成与分布具有明显的影响。

The Ban-2 oil group of Banqiao area is a typical condensate oil and gas reservoir.There are many difficulties in develop adjustment because of the complicated percolation and water flooding characteristic.So the experiment of gasliquid two phase flow was developed.The results show that gas-liquid fluid would be phase transition and mass transfer along with the changes of flow state and pressure.Fluid volatile have a relationship with the flow speed , fluid state and pressure.Reduce pressure will be beneficial to liquid volatile produce gas.The experimental results also show that the bubbles would be resistance for the crude oil flow in the step down water flood recovery process , when the pressure less than critical saturated pressure.The right time to water injection is the pressure reduced to more than87%of the bubble point pressure.In addition , the strength of the gas effect has obvious influence on the formation and distribution of remaining oil.