Abstract: Bounded reservoir produced oil mainly by self-expanding energy, and pressure decreases rapidly. It can increase bounded reservoir pressure and formation expansion ability by injecting CO₂ or flue gas. Injected flue gas, CO2 and heavy oil into a HTHP PVT equipment, and measured it's viscosity and volume factors in the condition 1 MPa to 7 MPa. Simulating heavy oil, after injected flue gas or CO₂ , pressure depleted recovery process by using core huff and puff experiment. Experimental results show the CO₂ and flue gas dissolved in oil can greatly decrease oil viscosity. Oil viscosity, saturated CO₂ , decreased more than 95%, and volume expansion increased 15% in 40 ℃, 7 MPa condition；but in the same condition oil viscosity, saturated flue gas, decreased 38.1%，and volume expansion increased 4.9%. Pressure depletion experiments show the injecting 0.4 PV gas is optimum. It can displace out 57.84% oil by injecting three runs o.4 PV CO₂; and get 43.99% by injecting three runs 0.4 PV flue gas. Oil recovery increases separately 17.31%, 13.29% by injecting 0.4 PV CO₂ or flue gas after water flooding.

Key words: 封闭油藏 , CO₂ , 烟道气 , 增能降粘 , 压力衰竭

摘要： 封闭油藏主要靠油藏自身的弹性能开采,能量衰竭很快。向地层注入C_O2或烟道气，可以增加封闭油藏的压力，补充地层弹性能。利用高温高压PVT设备，把注入烟道气或者CO₂和稠油充分混合，测得1 MPa到7 MPa条件下的烟道气或者CO₂稠油的粘度和体积系数。并用岩心实验模拟注入烟道气或者CO₂的稠油压力衰竭开采过程。实验表明,CO₂和烟道气在原油中有很好的降粘能力，40 ℃、7 MPa条件下分别饱和CO₂和烟道气，饱和CO₂原油的粘度降低幅度超过95%，体积膨胀15%；饱和烟道气的原油粘度降低38.1%，体积膨胀4.9%。压力衰竭实验表明,注入段塞的大小0.4 PV为宜；[CM(10]三轮次注气增能降粘[CM)]CO2能采出57.84%的原油；烟道气能采出43.99%原油；水驱后注气增能分别能提高采收率17.31%、13.29%。

关键词: 封闭油藏, CO₂, 烟道气, 增能降粘, 压力衰竭