摘要 |
<p>Methods produce heavy oil with steam assisted gravity drainage. Such methods alternate a traditional steam injection with an injection of a steam-plus-non-condensable gas (such as CO2 or CO2-plus-diluent) mixture. The CO2/diluent mixture is soluble in bitumen, leading to a reduction in viscosity of the heavy oil. Additionally, the steam-only injection reduces the accumulation of vapor NCG along the edge of the steam chamber, leading to improved thermal efficiency.</p> |