Partial oxidation process with production of power

• US 4,121,912 A
• Filed: 05/02/1977
• Issued: 10/24/1978
• Est. Priority Date: 05/02/1977
• Status: Expired due to Term

• Current Assignee: Texaco Incorporated (Chevron Corp.)
• Original Assignee: Texaco Incorporated (Chevron Corp.)
• Inventors: Alexander, David L., Muenger, James R., Schlinger, Warren G., Barber, Everett M.
• Primary Examiner(s): Bashore, S. Leon
• Assistant Examiner(s): Kratz, Peter F.
• Application Number:
  US05/793,008
• Time in Patent Office: 540 Days
• Field of Search: 48/197 R, 48/200, 48/201, 48/202, 48/203, 48/206, 48/209, 48/212, 48/215, 252/373, 60/39.02, 60/39.05, 60/39.12, 60/39.52, 60/39.18 R
• US Class Current: 48/197.00R
• CPC Class Codes: C10J 2300/092 Wood, cellulose
• CPC Class Codes: C10J 2300/093 Coal
• CPC Class Codes: C10J 2300/0943 Coke
• CPC Class Codes: C10J 2300/0946 Waste, e.g. MSW, tires, glass, tar sand, peat, paper, lignite, oil shale
• CPC Class Codes: C10J 2300/0956 Air or oxygen enriched air
• CPC Class Codes: C10J 2300/0959 Oxygen
• CPC Class Codes: C10J 2300/0976 as steam
• CPC Class Codes: C10J 2300/1671 with the production of electricity
• CPC Class Codes: C10J 2300/1675 making use of a steam turbine
• CPC Class Codes: C10J 2300/1807 Recycle loops, e.g. gas, solids, heating medium, water
• CPC Class Codes: C10J 2300/1846 Partial oxidation, i.e. injection of air or oxygen only
• CPC Class Codes: C10J 2300/1884 with one stream being synthesis gas
• CPC Class Codes: C10J 2300/1892 with one stream being water/steam
• CPC Class Codes: C10J 3/485 Entrained flow gasifiers
• CPC Class Codes: C10J 3/74 Construction of shells or jackets
• CPC Class Codes: C10J 3/78 High-pressure apparatus
• CPC Class Codes: C10J 3/84 with means for removing dust or tar from the gas
• CPC Class Codes: C10K 1/003 of acid contaminants, e.g. acid gas removal
• CPC Class Codes: C10K 1/101 with water only
• CPC Class Codes: C10K 1/16 with non-aqueous liquids
• CPC Class Codes: C10K 3/04 : reducing the carbon monoxide content , e.g. water-gas shift [WGS]
• CPC Class Codes: F02C 3/20 : using a special fuel, oxidant, or dilution fluid to generate the combustion products
• CPC Class Codes: Y02P 20/129 : Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines

Abstract

Power is developed by an expansion turbine in which the working fluid is a gaseous mixture comprising all of the hot raw gas stream leaving an unpacked partial oxidation gas generator, after removing if present a portion of the entrained solids, in admixture with a temperature moderating stream. A molal increase is associated with the partial oxidation process. Power is obtained from this molal increase in addition to the power obtained from the elevated pressure and sensible heat in the hot raw partial oxidation product gas. The temperature moderating stream may comprise a recycle portion of the turbine exhaust gas stream after being cooled, cleaned, optionally water-gas shifted or purified, or both, and recompressed. Alternatively, the recycle gas stream may be mixed with water, steam, or both. In one embodiment the temperature moderating stream comprises liquid water or condensate produced in the process. Auxiliary gas compressors for recompressing said recycle gas, and optionally for compressing a free-oxygen containing gas for use in the gas generation zone may be driven by said expansion turbine. Similarly, an electric generator may be coupled to the turbine shaft.

Claims

1. A process for the production of a product gas stream comprising H₂ and CO along with power comprising;

(1) producing a raw gas stream comprising H₂, CO, CO₂, H₂ O, and at least one member of the group H₂ S, COS, CH₄, N₂, and A, and containing entrained particulate carbon and other solids in the reaction zone of a free-flow gas generator by the partial oxidation of a hydrocarbonaceous fuel with a free-oxygen containing gas and with or without a temperature moderator, at a temperature in the range of about 1800°

to 3000°

F. and a pressure in the range of about 10 to 200 atmospheres;

(2) removing a portion of the entrained solids from the raw gas stream from (1), and in a mixing zone mixing all of said raw gas stream with a cooled, cleaned and compressed recycle gas stream from (6);

wherein the volume ratio of said recycle gas stream to the total gas mixture leaving said mixing zone is in the range of about 0.2 to 0.8;

(3) expanding the mixture of gas streams from (2) in a power recovery expansion turbine means at an inlet temperature in the range of about 1000°

to 2400°

F., and above the dew point and at an inlet pressure in the range of about 10 to 200 atm. abs.;

(4) removing a stream of gas from said turbine means in (3) at a pressure in the range of about 2 to 15 atm. abs. and a temperature in the range of about 350°

to 1000°

F., and cooling said gas stream;

(5) cleaning any remaining entrained particulate solids from the cooled gas stream from (4), and condensing and removing water;

(6) compressing the gas stream from (5) to a pressure greater than the pressure in said gas generator in a gas compression zone comprising at least one gas compressor operated from power produced by said expansion turbine, and passing a portion of the compressed gas stream into said mixing zone in (2) as said recycle gas stream; and

(7) removing the remainder of said compressed gas stream from said compression zone in (6) as said product gas stream.

2. The process of claim 1 where in step (2) the amounts and temperatures of the recycle gas stream and the raw gas stream from step (1) are such that the mixture of these gas streams is introduced into the turbine means in step (3) with an inlet temperature in the range of about 1400°

to 2200°

F.

3. The process of claim 1 with the addition of water or steam to the recycle gas stream from step (6).

4. The process of claim 1 provided with the additional step of removing in an absorption zone any acid-gases from the cleaned and dewatered gas stream from step (5) prior to being introduced into the compression zone in step (6).

5. The process of claim 1 where in step (5) prior to condensing said water, the gas stream is subjected to catalytic water-gas shift reaction.

6. The process of claim 1 provided with the additional step of removing in an absorption zone any acid gases from the gas stream leaving step (5).

7. The process of claim 1 provided with the additional step of removing in an absorption zone any acid gases from the compressed recycle gas stream leaving step (6).

8. The process of claim 5 provided with the additional step of removing in an acid-gas absorption zone any acid gases from the water-gas shifted gas stream.

9. The process of claim 1 provided with the additional step for producing electrical energy by coupling an electric generator to said power-recovery turbine means.

10. The process of claim 1 wherein the free-oxygen containing gas is selected from the group consisting of air, oxygen-enriched air (more than 21 mole % O₂) and substantially pure oxygen (more than 95 mole % O₂).

11. The process of claim 1 wherein said hydrocarbonaceous fuel is a liquid hydrocarbon selected from the group consisting of liquefied petroleum gas, petroleum distillates and residues, gasoline, naphtha, kerosine, crude petroleum, asphalt, gas oil, residual oil, tar-sand oil, shale oil, coal derived oil, aromatic hydrocarbons such as benzene, toluene, xylene fraction, coal tar, cycle gas oil from fluid-catalytic-cracking operation, furfural extract of coker gas oil, and mixtures thereof.

12. The process of claim 1 wherein said hydrocarbonaceous fuel is a gaseous hydrocarbon.

13. The process of claim 1 wherein said hydrocarbonaceous fuel is an oxygenated hydrocarbonaceous organic material selected from the group consisting of carbohydrates, cellulosic materials, aldehydes, organic acids, alcohols, ketones, oxygenated fuel oil, waste liquids and by-products from chemical processes containing oxygenated hydrocarbonaceous organic materials, and mixtures thereof.

14. The process of claim 1 where in step (2) said entrained solids are separated in a slag pot and are selected from the group consisting of particulate carbon, ash, slag, scale, refractory, metal constituents, and mixtures thereof.

15. The process of claim 1 wherein said hydrocarbonaceous fuel is a pumpable slurry of solid carbonaceous fuel selected from the group consisting of coal, lignite, wood pulp, particulate carbon, petroleum coke, and concentrated sewer sludge and mixtures thereof, in a vaporizable carrier such as water, liquid hydrocarbon and mixtures thereof.

16. The process of claim 1 wherein said product gas stream is synthesis gas or fuel gas.

17. A process for the production of a H₂ and CO-containing gas stream along with power comprising:

(1) producing a raw gas stream comprising H₂, CO, CO₂, H₂ O, and at least one member of the group H₂ S, COS, CH₄, N₂, and A, and containing entrained particulate solids in the reaction zone of a free-flow gas generator by the partial oxidation of a hydrocarbonaceous fuel with a free-oxygen containing gas and with or without a temperature moderator, at a temperature in the range of about 1800°

to 3000°

F. and a pressure in the range of about 10 to 200 atmospheres;

(2) removing a portion of the entrained solids from the hot raw process gas stream from (1);

(3) cooling the gas stream from (2) to a temperature in the range of about 1000°

to 2400°

F. and above the dew point by introducing water in liquid phase in the gas stream from (2) and then cooling the gas stream to a temperature in the range of about 350°

to 1000°

F. by expanding said gas stream in a power recovery turbine means from an inlet pressure in the range of about 10 to 200 atm. abs. to an outlet pressure in the range of about 2 to 15 atm. abs.;

wherein prior to introducing said water into said gas stream from (2) said water is preheated by indirect heat exchange with the gas stream leaving said turbine means;

(4) cooling and cleaning the remaining entrained particulate solids from the turbine exhaust gas stream leaving (3), and condensing and removing water from said gas stream;

(5) compressing the gas stream from (4) in a gas compression zone comprising at least one gas compressor operated from power produced by said expansion turbine; and

(6) removing the compressed gas stream from said compression zone in (5) as said H₂ and CO-containing product gas stream.

18. The process of claim 17 where at least a portion of the water introduced into the gas stream in step (3) to effect cooling is obtained from the water condensed from the gas stream in step (4).

19. The process of claim 17 where in step (4) prior to condensing said water, the gas stream is subjected to catalytic water-gas shift reaction.

20. The process of claim 19 provided with the additional step of removing in an acid-gas absorption zone any acid gases from the water-gas shifted gas stream.

21. The process of claim 17 provided with the additional step of removing acid-gases in an absorption zone from the gas stream from step (4) prior to introducing said gas stream into the compression zone in step (5).

22. The process of claim 17 provided with the additional step of removing in an absorption zone any acid gases from the gas stream leaving the compression zone in step (5).