Patent ID: 8997870
Filing Date: 2015-04-07
Classification: E21B

Abstract:
1. An apparatus for separating hydrocarbons and water produced from an underground formation comprising: a casing for lining a borehole in the formation; a tubing string in said casing defining an annulus with said casing; first perforations in said casing at a production zone of said borehole for introducing production fluid into the casing; second perforations in said tubing string for admitting production fluid from the casing into said tubing string; third perforations in said casing for discharging separated water from the annulus into the formation at an injection zone; a first packer in said annulus separating said first perforations from said third perforations; a first check valve in said tubing string above said packer for admitting production fluid under pressure from said tubing string into said annulus where the water separates by gravity from the hydrocarbons for discharge through said third perforations; and a second check valve in said tubing string above said first check valve for admitting separated hydrocarbons from said annulus into said tubing string for passage to the top of the borehole.