Patent ID: 7726402
Filing Date: 2010-06-01
Classification: E21B,Y02C

Abstract:
1. A method for sequestration of carbon dioxide in a formation traversed by a cased wellbore, comprising: a) finding a location in the formation having a first permeable layer directly overlain by a nearly impermeable layer, which in turn is overlain by a second permeable layer; b) completing the wellbore as a dual completion wellbore and with perforations in the casing for the purpose of injecting carbon dioxide into the first permeable layer and injecting water into the second permeable layer; and c) injecting carbon dioxide and water into their respective layers simultaneously, with the nearly impermeable layer therebetween, where the water is injected at a pressure of at least where p wi is the water injection pressure, p gi is the carbon dioxide injection pressure, g is the acceleration due to gravity, ρ g and ρ w are the densities of the carbon dioxide and water respectively, z m0 is the measurement point for pressure in said first permeable layer, z m2 is the measurement point for pressure in said second permeable layer, z 0 is the depth at the top of the first permeable layer, γ is the interfacial tension between said carbon dioxide and said water, φ 1 and k 1 are the porosity and the permeability of said nearly impermeable layer, and C is a constant.