Method for natural gas production

• US 7,513,306 B2
• Filed: 01/23/2008
• Issued: 04/07/2009
• Est. Priority Date: 07/22/2003
• Status: Active Grant

• Current Assignee: Precision Combustion, Inc.
• Original Assignee: Precision Combustion, Inc.
• Inventors: Pfefferle, William C.
• Primary Examiner(s): Bates; Zakiya W.
• Application Number:
  US12/009,949
• Publication Number:
  US 20080121393A1
• Time in Patent Office: 440 Days
• Field of Search: None
• US Class Current: 166/260
• CPC Class Codes: E21B 41/0064 Carbon dioxide sequestration storing fluids in porous layers B65G5/005
• CPC Class Codes: E21B 41/0099 specially adapted for drilling for or production of natural hydrate or clathrate gas reservoirs; Drilling through or monitoring of formations containing gas hydrates or clathrates
• CPC Class Codes: E21B 43/243 Combustion in situ
• CPC Class Codes: Y02C 20/40 of CO2

Abstract

A method of dissociating methane hydrate deposits in-situ is provided in which a supply of oxygen, carbon dioxide, and fuel are provided, the oxygen and the carbon dioxide are mixed to form an oxidizer fluid, and the fuel is combusted downhole by reacting it with the oxidizer fluid to provide hot combustion products. The combustion products are placed in contact with a diluent fluid to produce a cooled product fluid at a temperature higher than the prevailing methane hydrate decomposition temperature. The cooled product fluid is injected into the methane hydrate deposit decomposing the hydrate and releasing natural gas.

Claims

1. A method of dissociating methane hydrate deposits in-situ comprising:

a) providing a supply of oxygen;

b) providing a supply of carbon dioxide;

c) mixing the oxygen with the carbon dioxide to form an oxidizer fluid;

d) providing a supply of fuel;

e) combusting the fuel downhole by reacting it with the oxidizer fluid to provide hot combustion products;

f) contacting the combustion products with a diluent fluid to produce a cooled product fluid at a temperature higher than the prevailing methane hydrate decomposition temperature;

g) injecting the cooled product fluid into contact with the methane hydrate deposit; and

h) decomposing hydrate releasing natural gas.

2. The method of claim 1 wherein the carbon dioxide is provided by separating carbon dioxide from the produced natural gas.

3. The method of claim 1 wherein the fuel comprises a mixture of methane and carbon dioxide.

4. A method of dissociating methane hydrate deposits in-situ comprising:

a) providing a supply of oxygen;

b) providing a supply of fuel comprising methane and carbon dioxide;

c) combusting the fuel downhole by reacting it with the oxygen to provide hot combustion products;

d) contacting the combustion products with a diluent fluid to produce a cooled product fluid at a temperature higher than the prevailing methane hydrate decomposition temperature;

e) injecting the cooled product fluid into contact with the methane hydrate deposit; and

f) decomposing hydrate releasing natural gas.