U.S. patent application number 13/128603 was filed with the patent office on 2011-09-08 for method to increase gas mass flow injection rates to gas storage caverns using lng.
Invention is credited to Jose Lourenco, MacKenzie Millar.
Application Number | 20110214839 13/128603 |
Document ID | / |
Family ID | 42152417 |
Filed Date | 2011-09-08 |
United States Patent
Application |
20110214839 |
Kind Code |
A1 |
Lourenco; Jose ; et
al. |
September 8, 2011 |
METHOD TO INCREASE GAS MASS FLOW INJECTION RATES TO GAS STORAGE
CAVERNS USING LNG
Abstract
A method to increase gas mass flow loading rates to a gas
storage cavern includes using liquid natural gas (LNG) to cool
natural gas in a natural gas flow line upstream of a compressor
used to compress gas for storage in to a gas storage cavern.
Inventors: |
Lourenco; Jose; (Edmonton,
CA) ; Millar; MacKenzie; (Edmonton, CA) |
Family ID: |
42152417 |
Appl. No.: |
13/128603 |
Filed: |
November 10, 2008 |
PCT Filed: |
November 10, 2008 |
PCT NO: |
PCT/CA08/01975 |
371 Date: |
May 10, 2011 |
Current U.S.
Class: |
165/104.19 |
Current CPC
Class: |
F17C 2227/0395 20130101;
F17C 2223/0153 20130101; F17C 2227/0339 20130101; F17C 2227/0135
20130101; F17C 2227/0157 20130101; F17C 2250/0491 20130101; F17C
2250/0439 20130101; F17C 2201/052 20130101; F17C 2223/0123
20130101; F17C 5/06 20130101; F17C 2250/043 20130101; F17C
2270/0152 20130101; F17C 2260/025 20130101; F17C 2260/023 20130101;
F17C 2250/0636 20130101; F17C 2221/033 20130101 |
Class at
Publication: |
165/104.19 |
International
Class: |
F28D 15/00 20060101
F28D015/00 |
Claims
1. A method to increase gas mass flow injection rates to a gas
storage cavern, comprising: using liquid natural gas (LNG) to cool
natural gas in a natural gas flow line upstream of a compressor
used to compress gas for storage in to a gas storage cavern.
2. The method of claim 1, including a step of effecting a heat
exchange between the natural gas in the gas flow line upstream of
the compressor and LNG passing through a heat exchanger.
3. The method of claim 1, including a step of using LNG to cool
natural gas in the natural gas flow line downstream of a compressor
prior to the compressed natural gas entering the gas storage
cavern.
4. The method of claim 3, including a step of injecting LNG into
the natural gas flow line downstream of the compressor.
5. The method of claim 3, including a step of effecting a heat
exchange between the natural gas in the gas flow line downstream of
the compressor and LNG passing through a heat exchanger.
6. The method of claim 1, including a step of performing direct
injection of LNG into the gas storage cavern.
7. The method of claim 4, including a step of monitoring a
temperature of the gas storage cavern and controlling the injection
of LNG into the natural gas flow line downstream of the compressor
based upon the temperature of the gas storage cavern.
8. A method to increase gas mass flow injection rates to a gas
storage cavern, comprising: effecting a heat exchange between the
natural gas in a natural gas flow line upstream of a compressor
used to compress gas for storage in to a gas storage cavern and
liquid natural gas (LNG) passing through an upstream heat exchanger
to cool natural gas in the natural gas flow line upstream of a
compressor used to compress gas for storage in to a gas storage
cavern; and injecting LNG that has passed through the upstream heat
exchanger into one of the natural gas flow line downstream of the
compressor or into the gas storage cavern.
9. The method of claim 8, including a step of effecting a heat
exchange between the natural gas in the gas flow line downstream of
the compressor and LNG passing through a downstream heat
exchanger.
10. The method of claim 8, including a step of monitoring a
temperature of the gas storage cavern and performing injection of
LNG into one of the natural gas storage flow line downstream of the
compressor or the gas storage cavern, as required to maintain the
gas storage cavern at a preselected temperature.
Description
FIELD
[0001] The present invention relates to a method of increasing gas
mass flow injection rates to gas storage caverns using LNG.
BACKGROUND
[0002] Natural gas is traditionally stored in a gaseous form in
large volume salt caverns and aquifers to meet peak demand and
ensure a secure supply. The gas is added to storage by compression,
resulting in an increment in cavern temperature and an increment in
cavern pressure. These increments in pressure and temperature in
the cavern decrease the rate at which gas can be added to the
cavern.
SUMMARY
[0003] A method to increase gas mass flow injection rates to a gas
storage cavern, includes using liquid natural gas (LNG) to cool
natural gas in a natural gas flow line upstream of a compressor
used to compress gas for storage in to a gas storage cavern.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] These and other features of the invention will become more
apparent from the following description in which reference is made
to the appended drawings, the drawings are for the purpose of
illustration only and are not intended to in any way limit the
scope of the invention to the particular embodiment or embodiments
shown, wherein:
[0005] FIG. 1 is a schematic diagram that depicts an embodiment of
the teachings contained herein.
[0006] FIG. 2 is a variation on the embodiment shown in FIG. 1.
DETAILED DESCRIPTION
[0007] The preferred method to increase mass flow gas injection
rates will now be described with reference to FIG. 1.
[0008] Gas is supplied from main pipeline stream 1. The gas to
storage is routed through line 2 to exchanger 30 where it is cooled
by LNG. The cooler gas exits exchanger 30 via stream 3 to knock out
drum 31, to remove any condensate and debris present in the stream.
The condensate is removed through stream 4. The cold gas is routed
through stream 5 to compressor 32 for injection into cavern 33 via
stream 6. LNG is supplied from tank 35 and is routed through line 8
to pump 36 where it is pressurized and routed through line 9. The
LNG is routed through line 10 to exchanger 30, to cool the gas to
storage and exits the exchanger through line 11. The gas in stream
11 is colder than compressed gas in stream 6. The gas can then be
routed through valve 39 and line 12 to mix directly with stream 6
in mixer 41, increasing the gas density of gas stream 7 to storage
33. The option of routing stream 11 through valve 38 and line 13
directly to storage cavern 33 is available. The operating
conditions for the cavern are monitored by pressure and temperature
sensors 34. The objective is to increase the gas injection rate of
compressor 32 by lowering the temperature of the gas suction line
to the compressor, making the gas denser, thus increasing the mass
flow rate and also decreasing the compressor outlet temperature.
The compressor outlet temperature can be further decreased by
direct mixing of stream 12 with stream 6. For every incremental
decrease in the temperature of gas entering cavern 33, the amount
of gas cavern 33 is capable of storing increases. If it is
desirable to further decrease the temperature of cavern 33, the
option of routing stream 11 through valve 38 and line 13 directly
to storage cavern 33 is followed.
[0009] A variation will now be described with reference to FIG.
2.
[0010] Gas is supplied from main pipeline stream 1. The gas to
storage is routed through line 2 to exchanger 30 where it is cooled
by LNG. The cooler gas exits exchanger 30 via stream 3 to knock out
drum 31 to remove any condensate and debris present in the stream.
The condensate is removed through stream 4. The cold gas is routed
through stream 5 to compressor 32, where it is compressed and
delivered through line 6 to exchanger 41 where it is cooled. The
compressed and cooled stream 7 mixes with stream 11 and is stored
through line 12 into gas cavern storage 33. LNG is supplied from
tank 35 and is routed through line 8 to pump 36 where it is
pressurized and routed through line 9. The LNG is routed to
exchanger 30, to cool the gas to storage and exits the exchanger
through line 10. The gas in stream 10 is colder than compressed gas
in stream 6. The gas stream 10 enters exchanger 41 to cool the
compressor discharge gas. The gas can then be routed through valve
39 to mix directly with stream 7 to storage 33 through line 12. The
option of routing stream 11 through valve 38 and line 13 directly
to storage cavern 33 is available. The operating conditions for the
cavern are monitored by pressure and temperature sensors 34. The
objective is to increase the gas mass flow injection rate of
compressor 32 by lowering the temperature of the gas suction line
to the compressor, making the gas denser, thus increasing the mass
flow rate whilst also decreasing the compressor outlet temperature.
The compressor outlet temperature is further decreased by indirect
mixing of stream 10 with stream 6 thus further improving the power
requirements for compression. The described embodiment of FIG. 3
provides the ability for gas cavern operators to increase the mass
flow gas injection rates to cavern storage.
[0011] The stored gas exits the cavern via stream 50 to meet
demand.
[0012] In this patent document, the word "comprising" is used in
its non-limiting sense to mean that items following the word are
included, but items not specifically mentioned are not excluded. A
reference to an element by the indefinite article "a" does not
exclude the possibility that more than one of the element is
present, unless the context clearly requires that there be one and
only one of the elements.
[0013] It will be apparent to one skilled in the art that
modifications may be made to the illustrated embodiments without
departing from scope of the Claims.
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