Downhole combustor

Patent metadata

Field	Value
Publication number	US-9228738-B2
Application number	US-201313745196-A
Country	US
Kind code	B2
Filing date	Jan 18, 2013
Priority date	Jun 25, 2012
Publication date	Jan 5, 2016
Grant date	Jan 5, 2016

Abstract

A downhole combustor system for a production well is provided. The downhole combustor includes a housing, a combustor and an exhaust port. The housing is configured and arranged to be positioned down a production well. The housing further forms a combustion chamber. The combustor is received within the housing. The combustor is further configured and arranged to combust fuel in the combustion chamber. The exhaust port is positioned to deliver exhaust fumes from the combustion chamber into a flow of oil out of the production well.

First claim

The invention claimed is:

1. A downhole combustor system comprising:
a longitudinally extending housing configured and arranged to be positioned down a wellbore of a production well, the housing including:
a first housing portion having an oil and gas mixing chamber, the first housing portion having at least one inlet ort to the oil and as mixing chamber to allow passage of oil from an oil reservoir in communication with the wellbore into the oil and gas mixing chamber, the first housing portion further having at least one outlet port out of the oil and gas mixing chamber to allow passage of mixed oil from the oil reservoir and exhaust gas out of the oil and gas mixing chamber into the wellbore, the at least one outlet port spaced a longitudinal distance above the at least one inlet port; and
a second housing portion comprising a combustion chamber below the first housing portion, the second housing portion coupled to the first housing portion;

a combustor below the combustion chamber configured and arranged to combust fuel in the combustion chamber;
a plurality of heat exchange tubes received within the first portion of the housing proximate the oil and gas mixing chamber and laterally adjacent to the at least one inlet port, the heat exchange tubes coupled to transfer heat of exhaust gases generated in the combustion chamber and passing through the plurality of heat exchange tubes to oil entering the first portion of the housing through the at least one inlet port;

at least one exhaust port positioned to deliver exhaust gases from at least some of the plurality of heat exchange tubes into the oil and gas mixing chamber; and
a packing seal disposed about the housing between the at least one inlet port and the at least one outlet port for providing a seal between the housing and a casing lining the wellbore.

2. The downhole combustor system of claim 1 , wherein:
the housing has a plurality of delivery passages; and
further comprising at least one input delivery connector in fluid communication with at least one of the delivery passages to deliver at least one of air and fuel to the combustor.

3. The downhole combustor system of claim 2 , wherein the plurality of delivery passages in the housing is configured and arranged to cool the housing.

4. The downhole combustor system of claim 1 , further comprising:
a third housing portion coupled to the second housing portion and housing the combustor.

5. The downhole combustor system of claim 4 , further comprising:
a sleeve configured and arranged to couple the second housing portion to the first housing portion.

6. The downhole combustor system of claim 1 , wherein the plurality of heat exchange tubes form at least a part of
a heat exchange system received in the housing proximate the combustion chamber, the heat exchange system configured and arranged to transfer heat from the combustion chamber to oil within the first portion of the housing.

7. The downhole combustor system of claim 1 , further comprising:
at least one of a thermal gas lift system, an energy generating system and an oil reforming system.

8. A downhole combustor system for a production well, the downhole combustor system comprising:
a housing configured for disposition in a wellbore and comprising an oil and exhaust gas mixing chamber and a combustion chamber, the housing having at least one oil input port passing through an outer shell of the housing allowing passage into the housing of oil from an oil reservoir in communication with the wellbore, the housing further having at least one oil and exhaust gas output port passing through the outer shell of the housing at a longitudinally spaced distance from the at least one oil input port, the at least one oil and exhaust gas output port configured and arranged to pass oil and exhaust gas out of the housing, the housing further having at least one delivery passage within the outer shell of the housing;
a packing seal disposed about the housing between the at least one oil input port and the at least one oil and exhaust gas output port for providing a seal between the housing and a casing lining the wellbore;
at least one delivery connector coupled to the housing, the at least one delivery connector in fluid communication with at least one associated delivery passage;
a combustor configured and arranged to combust fuel in a combustion chamber, the combustor configured and arranged to receive fuel and air passed through the at least one delivery passage;
a plurality of heat exchange tubes received within the housing proximate the oil and exhaust mixing chamber, each heat exchange tube coupled to receive exhaust gases generated in the combustion chamber, to transfer heat from the exhaust gases to oil in the housing; and
exhaust ports positioned to pass exhaust gases from at least some heat exchange tubes of the plurality to the oil and exhaust gas mixing chamber.

9. The downhole combustor system of claim 8 , wherein the housing further comprises:
a first housing portion, the first housing portion having a first end and an opposed, second end, the first housing portion forming the oil and exhaust gas mixture chamber;
a second housing portion, a first end of the second housing portion coupled to the second end of the first housing portion, the second housing portion comprising the combustion chamber; and
a third housing portion coupled to a second end of the second housing portion and containing the combustor.

10. The downhole combustor system of claim 8 , wherein the plurality of heat exchange tubes form at least part of a heat exchange system received in the housing proximate the combustion chamber, the heat exchange system configured and arranged to transfer heat generated in the combustion chamber to oil in the oil and exhaust gas mixing chamber.

11. The downhole combustor system of claim 8 , further comprising:
at least one of a thermal gas lift system, an energy generating system and a reforming system.

12. A method of extracting oil from an oil reservoir, the method comprising:
positioning a downhole combustor in a wellbore in communication with the oil reservoir;
sealing the wellbore between a casing structure lining the wellbore and an exterior of a housing containing an oil and gas mixing chamber, a combustor and a combustion chamber of the combustor system with a packing seal;
delivering fuel to the combustor through passages in the housing;
initiating an ignition system of the combustor to combust the fuel in the combustion chamber;
heating oil passing into the housing from the oil reservoir below the packing seal with a plurality of heat exchange tubes positioned below the oil and gas mixing chamber that are in communication with exhaust gases from the combustion chamber;
mixing the oil passed into the housing with exhaust gases exiting at least some of the plurality of heat exchange tubes into the oil and gas mixing chamber; and
venting exhaust gases mixed with oil from the housing into the wellbore above the packing seal.

13. The method of claim 12 , further comprising:
cooling the housing with fuel delivered through passages in the housing.

14. The method of claim 12 , further comprising:
reforming oil, at least in part in the combustor with the exhaust gases from the combustion chamber.

15. The method of claim 12 , further comprising:
generating mechanical work using energy from the exhaust gases from the combustion chamber.

Assignees

• Orbital Atk Inc

Inventors

• Tilmont Daniel
• Custodio Troy

Classifications

• F22B27/02

  built-up from fire tubes · CPC title

• F22B27/12

  built-up from rotary heat-exchange elements, e.g. from tube assemblies · CPC title

• F23Q7/00

  Incandescent ignition; Igniters using electrically-produced heat, e.g. lighters for cigarettes (circuits therefor H01T15/00); Electrically-heated glowing plugs · CPC title

• E21B36/02 Primary

  using burners · CPC title

• F22B1/1853 Primary

  coming in direct contact with water in bulk or in sprays · CPC title