Method of heating a subterranean formation

• US 3,931,856 A
• Filed: 12/23/1974
• Issued: 01/13/1976
• Est. Priority Date: 12/23/1974
• Status: Expired due to Term

• Current Assignee: Atlantic Richfield Company Incorporated (BP PLC)
• Original Assignee: Atlantic Richfield Company Incorporated (BP PLC)
• Inventors: Barnes, Allen L.
• Primary Examiner(s): Novosad, Stephen J.
• Application Number:
  US05/535,162
• Time in Patent Office: 386 Days
• Field of Search: 166/248, 166/272, 166/60, 166/263, 166/271, 166/245, 166/302
• US Class Current: 166/245
• CPC Class Codes: E21B 43/2401 by means of electricity
• CPC Class Codes: E21B 43/30 Specific pattern of wells, e.g. optimising the spacing of wells

Abstract

An improved method of recovering a fluid from a subterranean formation via heating by electrical conduction between a plurality of wells completed therein, the improvement comprising drilling and completing a satellite well open to the formation and adjacent an electrode well, injecting water containing dissolved electrolyte into the formation via the electrode well having an adjacent satellite well, establishing fluid communication between the electrode well and the satellite well, and circulating the water containing dissolved electrolyte between the electrode well and adjacent satellite well. This invention increases the electrical conductivity in the formation and about the wells where the current flux is greatest and makes possible larger current than would otherwise be possible with a given voltage differential. Also disclosed are specific embodiments.

Claims

1. In a method of recovering an in situ fluid from a subterranean formation containing viscous oil via heating with electrical conduction between a plurality of electrode wells completed therein, in order to improve the conductivity between said electrode wells, the improvement comprises:

drilling and completing a satellite well in said formation and adjacent an electrode well,

injecting water containing dissolved electrolyte into said formation via an electrode well having an adjacent satellite well,

establishing fluid communication between said electrode well and said satellite well by repeated steps of heating and producing mobilized in situ fluid situated therebetween, and

circulating said water containing dissolved electrolyte between said electrode well and adjacent satellite well.

2. The improvement of claim 1 wherein said circulation is provided by withdrawing said injected water from said formation through said satellite well and passing same through a heat exchanger at the surface and reinjecting same into said formation through said electrode well whereby same flows past conductors situated therein.

3. The improvement of claim 1 wherein said circulation is provided by withdrawing said injected water from said formation through said electrode well and passing same through a heat exchanger at the surface and reinjecting same into said formation through said electrode well whereby same flows past conductors situated therein.

4. The improvement of claim 1 wherein said electrode well has adjacent thereto three satellite wells positioned equidistance from said electrode well and each other.