Methods for producing a fuel gas stream

Patent metadata

Field	Value
Publication number	US-9964034-B2
Application number	US-201514671029-A
Country	US
Kind code	B2
Filing date	Mar 27, 2015
Priority date	Apr 9, 2014
Publication date	May 8, 2018
Grant date	May 8, 2018

Abstract

Methods and systems for dynamically planning a well site are provided herein. Methods include flowing a raw gas stream though a suction scrubber to form a feed gas stream and compressing the feed gas stream to form a compressed gas stream. Methods include cooling the compressed gas stream in a cooler to produce a cooled gas stream. Methods include feeding the cooled gas stream into a gas treatment system, using a turboexpander, to produce a conditioned gas and a waste stream. Methods include heating the conditioned gas in a heat exchanger, where the conditioned gas is a superheated, sweetened, gas. Methods also include burning the conditioned gas in a turbine generator and mixing the waste stream into the raw gas stream upstream of the suction scrubber.

First claim

What is claimed is:

1. A method for producing a fuel gas stream, comprising:
flowing a raw gas stream through a suction scrubber to form a feed gas stream;
compressing the feed gas stream to form a compressed gas stream;
cooling the compressed gas stream in a cooler to produce a cooled gas stream;
feeding the cooled gas stream into a gas treatment system, using a turboexpander, to produce a conditioned gas and a waste stream;
heating the conditioned gas in a heat exchanger, wherein the conditioned gas is a superheated, sweetened gas;
burning the conditioned gas in a turbine generator; and
mixing the waste stream into the raw gas stream upstream of the suction scrubber.

2. The method of claim 1 , comprising separating condensed liquids from a cooled gas stream to form a flash stream, wherein the flash stream is fed into a raw gas stream upstream of a suction scrubber.

3. The method of claim 1 , comprising dehydrating a cooled gas stream, within a gas treatment system, to produce a dry gas stream and a waste water stream, wherein the waste water stream is fed into a raw gas stream upstream of a suction scrubber.

4. The method of claim 1 , comprising feeding a portion of a cold vapor stream into a regeneration gas separator to produce a regeneration liquids stream and a regeneration gas stream, wherein the regeneration liquids stream is fed into the raw gas stream upstream of the suction scrubber.

5. The method of claim 1 , comprising feeding a portion of a cold vapor stream into a cryogenic expander, wherein a contaminant rich liquid is produced.

6. The method of claim 1 , comprising feeding a conditioned gas into a compressor before heating.

7. The method of claim 1 , comprising pumping a waste stream into a raw gas stream upstream of a suction scrubber.

8. The method of claim 1 , comprising heating a waste stream and a regeneration gas stream in a heat exchanger before entering a suction scrubber.

9. The method of claim 1 , comprising heating a conditioned gas, a waste stream, and a regeneration gas stream in a cooling water loop after heating in a heat exchanger.

10. A system for producing a fuel gas stream, comprising
a suction scrubber to form a feed gas stream from a raw gas stream;
a compressor to form a compressed gas stream from the feed gas stream;
a cooling water system to cool the compressed gas stream to produce a cooled gas stream;
a gas treatment system, comprising an expansion device and a low temperature separation step, to remove contaminants from the cooled gas stream to produce a fuel gas and a waste stream, wherein the waste stream is mixed into the raw gas stream upstream of the suction scrubber;
a heat exchanger to superheat the fuel gas to produce a superheated, sweetened gas; and
a turbine generator to combust the superheated, sweetened gas.

11. The system of claim 10 , wherein a compressed gas stream is fed into a cooling water system from at least about 1,900 psia to produce a cooled gas stream.

12. The system of claim 10 , wherein a cooling water system uses water or a glycol/water mixture to cool a compressed gas stream to reduce moisture content.

13. The system of claim 10 , comprising a vapor/liquid separator to condense and remove liquids from a compressed gas stream to produce a flash stream that is fed into a raw gas stream upstream of a suction scrubber.

14. The system of claim 10 , wherein a gas treatment system comprises a dehydration section, a scrubber section, and a cryogenic expander section.

15. The system of claim 10 , comprising a dehydration section configured to remove liquids from a cooled gas stream to form a waste water stream, wherein a waste water stream is fed into a raw gas stream upstream of a suction scrubber.

16. The system of claim 10 , comprising an expansion device configured to remove condensed liquids from a cooled gas stream to form a cold vapor stream and a liquid stream, wherein the liquid stream is fed into a raw gas stream upstream of a suction scrubber.

17. The system of claim 10 , comprising a regeneration gas separator to separate a portion of a cold vapor stream to produce a regeneration gas stream and a regeneration liquids stream, wherein the regeneration liquids stream is fed into a raw gas stream upstream of a suction scrubber.

18. The system of claim 10 , comprising a compressor to compress a fuel gas before heating.

19. The system of claim 10 , wherein a waste stream comprises contaminants, water, or in any combination thereof, wherein a pump increases a pressure of the waste stream for injection into a raw gas stream upstream of a suction scrubber.

20. The system of claim 10 , wherein a heat exchanger heats a waste stream and a regeneration gas stream before entering a suction scrubber.

21. The system of claim 10 , comprising a cooling water loop to heat a fuel gas, a waste stream, and a regeneration gas stream after heating in a heat exchanger.

22. A method for producing a fuel gas from a compressed natural gas, comprising:
flowing a raw natural gas through a suction scrubber to form a natural gas feed;
compressing the natural feed gas to form a compressed natural gas;
cooling the compressed natural gas in a cooler to produce a cooled natural gas;
feeding the cooled natural gas into a gas treatment system, comprising a low-temperature separator, to produce a natural gas stream and a waste stream;
heating the natural gas stream in a heat exchanger to form a superheated, sweetened natural gas;
combusting the superheated, sweetened natural gas in a turbine generator for use as an energy source; and
mixing the waste stream into the raw natural gas located upstream of the suction scrubber.

23. The method of claim 22 , wherein a portion of cooled natural gas directed into a gas treatment system includes less than about 15%, about 10%, about 5%, or less of the total amount of the compressed natural gas.

24. The method of claim 22 , comprising removing condensed liquids from a cooled natural gas stream to form a flash stream, wherein the flash stream is fed into an upstream compression scrubber.

25. The method of claim 22 , comprising dehydrating a cooled natural stream, within a gas treatment system, to produce a cold natural gas stream and a waste water stream, wherein the waste water stream is fed into a raw gas stream upstream of a suction scrubber.

26. The method of claim 22 , comprising removing condensed liquids from a cooled natural gas stream in an expansion device, within a gas treatment system, to produce a cold vapor natural gas and a liquid stream, wherein the liquid stream is fed into a raw gas stream upstream of a suction scrubber.

27. The method of claim 22 , comprising feeding a portion of a cold vapor natural gas into a regeneration gas separator to generate a regeneration gas stream and a regeneration liquids stream, wherein the regeneration liquids stream is fed into the raw gas stream upstream of the suction scrubber.

28. The method of claim 22 , comprising feeding a natural gas stream into a compressor before heating and wherein a waste stream is pumped into a raw gas stream upstream of a suction scrubber.

29. The method of claim 22 , comprising heating a waste stream and a regeneration gas stream in a heat exchanger before flowing the waste stream and the regeneration gas into a suction scrubber.

30. The meth

Assignees

• Denton Robert D
• Exxonmobil Upstream Res Co

Inventors

• Denton Robert D

Classifications

• C10L3/103

  Sulfur containing contaminants · CPC title

• C10L3/106

  of water · CPC title

• F05D2220/75

  equipment using fuel having a low calorific value, e.g. low BTU fuel, waste end, syngas, biomass fuel or flare gas · CPC title

• C10L3/104

  Carbon dioxide · CPC title

• F02C3/20 Primary

  using a special fuel, oxidant, or dilution fluid to generate the combustion products · CPC title