Patent ID: 9115577
Filing Date: 2015-08-25
Classification: C09K,E21B

Abstract:
1. A process for the recovery of hydrocarbons from a hydrocarbon bearing formation in which are situated an upper injection well and a lower production well, the method comprising the steps: preheating the region between the wells by circulating hot solvent through at least part of both of the wells until hydraulic communication between both wells is achieved; injecting butane into the upper injection well at or above its critical temperature, thereby: i) creating a hot solvent chamber consisting of solvent vapour and liquid, ii) mixing of the bitumen and the solvent at the boundary of the solvent chamber so formed, and iii) causing a mixture of the hydrocarbon and solvent to drain downwards by gravity and sideways by pressure gradient towards the lower production well; and producing the mixture to the surface through the lower production well.