Unconditioned syngas composition and method of cleaning up same for fischer-tropsch processing

• US 10,280,081 B2
• Filed: 08/30/2018
• Issued: 05/07/2019
• Est. Priority Date: 09/27/2011
• Status: Active Grant

• Current Assignee: Thermochem Recovery International, Inc.
• Original Assignee: Thermochem Recovery International, Inc.
• Inventors: Chandran, Ravi, Leo, Daniel Michael, Freitas, Shawn Robert, Newport, Dave G., Whitney, Hamilton Sean Michael, Burciaga, Daniel A.
• Primary Examiner(s): Call, Douglas B
• Application Number:
  US16/117,039
• Publication Number:
  US 20190010050A1
• Time in Patent Office: 250 Days
• CPC Class Codes: B01D 17/0208 by sedimentation
• CPC Class Codes: B01D 2252/102 Ammonia
• CPC Class Codes: B01D 2252/103 Water
• CPC Class Codes: B01D 2252/20436 Cyclic amines
• CPC Class Codes: B01D 2252/504 Mixtures of two or more absorbents
• CPC Class Codes: B01D 2252/602 Activators, promoting agents, catalytic agents or enzymes
• CPC Class Codes: B01D 2256/16 Hydrogen
• CPC Class Codes: B01D 2256/20 Carbon monoxide
• CPC Class Codes: B01D 2257/304 Hydrogen sulfide
• CPC Class Codes: B01D 2257/306 Organic sulfur compounds, e.g. mercaptans
• CPC Class Codes: B01D 2257/406 Ammonia
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01D 2257/60 Heavy metals or heavy metal compounds
• CPC Class Codes: B01D 2257/708 Volatile organic compounds V.O.C.'s
• CPC Class Codes: B01D 2259/402 using two beds
• CPC Class Codes: B01D 29/27 Filter bags
• CPC Class Codes: B01D 29/66 by flushing, e.g. counter-current air-bumps
• CPC Class Codes: B01D 46/0036 by adsorption or absorption
• CPC Class Codes: B01D 47/10 Venturi scrubbers
• CPC Class Codes: B01D 5/0027 by direct contact between vapours or gases and the cooling medium
• CPC Class Codes: B01D 5/006 : with evaporation or distillation
• CPC Class Codes: B01D 5/0072 : with filtration
• CPC Class Codes: B01D 5/0075 : with heat exchanging B01D5/0039 takes precedence
• CPC Class Codes: B01D 5/009 : Collecting, removing and/or treatment of the condensate
• CPC Class Codes: B01D 50/60 : Combinations of devices covered by groups B01D46/00 and B01D47/00
• CPC Class Codes: B01D 53/0423 : Beds in columns
• CPC Class Codes: B01D 53/0462 : Temperature swing adsorption
• CPC Class Codes: B01D 53/047 : Pressure swing adsorption
• CPC Class Codes: B01D 53/0476 : Vacuum pressure swing adsorption
• CPC Class Codes: B01D 53/12 : according to the "fluidised technique"
• CPC Class Codes: B01D 53/1406 : Multiple stage absorption
• CPC Class Codes: B01D 53/1412 : Controlling the absorption process
• CPC Class Codes: B01D 53/1431 : Pretreatment by other processes
• CPC Class Codes: B01D 53/1462 : Removing mixtures of hydrogen sulfide and carbon dioxide
• CPC Class Codes: B01D 53/1468 : Removing hydrogen sulfide
• CPC Class Codes: B01D 53/1487 : Removing organic compounds
• CPC Class Codes: B01D 53/18 : Absorbing units; Liquid distributors therefor B01D3/16, B01D3/26, B01D3/30 take precedence; packing elements B01J19/30, B01J19/32
• CPC Class Codes: B01D 53/265 : by refrigeration (condensation)
• CPC Class Codes: B01D 53/326 : in electrochemical cells
• CPC Class Codes: B01D 53/48 : Sulfur compounds
• CPC Class Codes: B01D 53/76 : Gas phase processes, e.g. by using aerosols
• CPC Class Codes: B01D 61/362 : Pervaporation
• CPC Class Codes: B01D 61/3621 : comprising multiple pervaporation steps
• CPC Class Codes: C01B 2203/0227 : containing a catalytic reforming step
• CPC Class Codes: C01B 2203/0233 : the reforming step being a steam reforming step
• CPC Class Codes: C01B 2203/025 : containing a partial oxidation step
• CPC Class Codes: C01B 2203/0261 : containing a catalytic partial oxidation step [CPO]
• CPC Class Codes: C01B 2203/04 : containing a purification step for the hydrogen or the synthesis gas
• CPC Class Codes: C01B 2203/0415 : Purification by absorption in liquids
• CPC Class Codes: C01B 2203/042 : Purification by adsorption on solids
• CPC Class Codes: C01B 2203/043 : Regenerative adsorption process in two or more beds, one for adsorption, the other for regeneration
• CPC Class Codes: C01B 2203/0435 : Catalytic purification
• CPC Class Codes: C01B 2203/045 : Purification by catalytic desulfurisation
• CPC Class Codes: C01B 2203/0465 : Composition of the impurity
• CPC Class Codes: C01B 2203/0475 : the impurity being carbon dioxide
• CPC Class Codes: C01B 2203/048 : the impurity being an organic compound
• CPC Class Codes: C01B 2203/0485 : the impurity being a sulfur compound
• CPC Class Codes: C01B 2203/061 : Methanol production
• CPC Class Codes: C01B 2203/062 : Hydrocarbon production, e.g. Fischer-Tropsch process
• CPC Class Codes: C01B 2203/068 : Ammonia synthesis
• CPC Class Codes: C01B 2203/0877 : by direct injection of fluid
• CPC Class Codes: C01B 2203/1235 : Hydrocarbons
• CPC Class Codes: C01B 2203/1241 : Natural gas or methane
• CPC Class Codes: C01B 2203/142 : At least two reforming, decomposition or partial oxidation steps in series
• CPC Class Codes: C01B 2203/147 : Three or more purification steps in series
• CPC Class Codes: C01B 2203/84 : Energy production
• CPC Class Codes: C01B 3/24 : of hydrocarbons
• CPC Class Codes: C01B 3/38 : using catalysts
• CPC Class Codes: C01B 3/382 : Multi-step processes
• CPC Class Codes: C01B 3/386 : Catalytic partial combustion
• CPC Class Codes: C01B 3/52 : by contacting with liquids; Regeneration of used liquids C01B3/508 takes precedence
• CPC Class Codes: C01B 3/56 : by contacting with solids; Regeneration of used solids C01B3/508 takes precedence
• CPC Class Codes: C01B 3/58 : including a catalytic reaction
• CPC Class Codes: H05K 999/99 : dummy group
• CPC Class Codes: Y02C 20/40 : of CO2
• CPC Class Codes: Y02P 20/129 : Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines
• CPC Class Codes: Y02P 30/00 : Technologies relating to oil refining and petrochemical industry

Abstract

A system and method for processing unconditioned syngas first removes solids and semi-volatile organic compounds (SVOC), then removes volatile organic compounds (VOC), and then removes at least one sulfur containing compound from the syngas. Additional processing may be performed depending on such factors as the source of syngas being processed, the products, byproducts and intermediate products desired to be formed, captured or recycled and environmental considerations.

Claims

1. A method of producing Fischer-Tropsch products, comprising:

(a) providing an unconditioned syngas;

(b) after step (a), hydrocarbon reforming the unconditioned syngas with an oxidant source to generate additional hydrogen and carbon monoxide and produce a syngas of improved quality, wherein the oxidant source includes one or more selected from the group consisting of carbon dioxide, steam, air, and oxygen;

(c) after step (b), cooling the syngas of improved quality;

(d) after step (c), removing at least a portion of the steam from the syngas of improved quality;

(e) after step (d), compressing the syngas of improved quality;

(f) after step (e), removing from the syngas of improved quality, one or more volatile organic compounds from the group consisting of benzene, toluene, phenol, styrene, xylene, and cresol;

(g) after step (f), removing ammonia from the syngas of improved quality, thereby producing an ammonia-depleted syngas of improved quality;

(h) after step (g), removing carbon dioxide from the ammonia-depleted syngas of improved quality, thereby forming an ammonia-and-carbon-dioxide-depleted syngas of improved quality; and

(i) after step (h), introducing the ammonia-and-carbon-dioxide-depleted syngas of improved quality to a Fischer-Tropsch (FT) catalytic synthesis process and generating Fischer-Tropsch products including at least a Medium Fraction Fischer-Tropsch Liquid (MFFTL) and wax.

2. The method according to claim 1, further comprising:

hydrocarbon reforming by partial oxidation and/or

hydrocarbon reforming by using a catalyst.

3. The method according to claim 1, comprising:

(b1) in step (b) and before step (c), mixing the unconditioned syngas with a gaseous hydrocarbon and an oxidant; and

(b2) reacting the unconditioned syngas with said gaseous hydrocarbon and said oxidant to generate said additional hydrogen and carbon monoxide;

wherein;

said gaseous hydrocarbons are converted into said additional hydrogen and carbon monoxide at a conversion efficiency between 50% and 100%;

the gaseous hydrocarbon includes one or more selected from the group consisting of natural gas, syngas, refinery offgases, methanol, ethanol, petroleum, methane, ethane, propane, butane, hexane, benzene, toluene, xylene, wax, low melting solids, paraffin wax, and naphthalene;

the oxidant includes one or more selected from the group consisting of carbon dioxide, steam, air, and oxygen.

4. The method according to claim 3, further comprising:

cooling the syngas of improved quality in a shell and tube heat exchanger, wherein the syngas of improved quality travels through the tube-side and indirectly contacts steam located on the shell-side.

5. The method according to claim 1, further comprising:

in step (c), cooling the syngas of improved quality to between 250 degrees Fahrenheit and 650 degrees Fahrenheit.

6. The method according to claim 1, further comprising:

in step (c), cooling the syngas of improved quality and generating superheated steam by using a heat recovery steam generator superheater (HRSG superheater) configured to receive steam from a steam drum;

further cooling the syngas of improved quality and generating steam using a heat recovery steam generator (HRSG) configured to receive water from the steam drum; and

transferring the steam generated by the HRSG back to the steam drum.

7. The method according to claim 1, further comprising:

after step (c) and before step (d), generating superheated steam from steam, by cooling at least a portion of the said additional hydrogen and carbon monoxide generated by said hydrocarbon reforming.

8. The method according to claim 1, further comprising:

in step (d), removing said steam from at least a portion of the syngas of improved quality by condensing said steam within a scrubber.

9. The method according to claim 1, further comprising:

in step (e), compressing the syngas of improved quality with a compressor from a first pressure ranging from 15 PSIG to 50 PSIG to a second higher pressure ranging from 100 PSIG to 2,000 PSIG.

10. The method according to claim 1, further comprising:

in step (f), removing said VOCs with an adsorbent.

11. The method according to claim 10, further comprising:

desorbing said adsorbent via pressure swing desorption and/or temperature swing desorption.

12. The method according to claim 1, further comprising:

in step (f), removing said VOCs with an adsorbent including one or more selected from the group consisting of styrene based polymeric adsorbents, molecular sieves, zeolites, catalyst materials, silica gel, alumina, and activated carbon materials.

13. The method according to claim 1, further comprising:

in step (f), removing said VOCs with a capture efficiency greater than 95%.

14. The method according to claim 1, further comprising:

in step (g), removing ammonia from the syngas of improved quality by use of a scrubber.

15. The method according to claim 1, further comprising:

in step (h), removing carbon dioxide from the ammonia-depleted syngas of improved quality with one or more selected from the group consisting of a membrane, an adsorber, and an absorber;

wherein the carbon dioxide capture efficiency of step (h) is greater than 20%.

16. The method according to claim 1, wherein the unconditioned syngas has a component composition comprising:

(a) a carbon monoxide concentration ranging from between 5 volume percent to 35 volume percent on a dry basis;

(b) a hydrogen concentration ranging from between 20 volume percent to 60 volume percent on a dry basis;

(c) one or more volatile organic compounds (VOC) selected from the group consisting of benzene, toluene, phenol, styrene, xylene, cresol, and combinations thereof, the VOC concentration ranges from between 500 parts per million by volume to 10,000 parts per million by volume on a dry basis;

(d) one or more semi-volatile organic compounds (SVOC) selected from the group consisting of indene, indan, napthalene, methylnapthalene, acenapthylene, acenapthalene, anthracene, phenanthrene, (methyl-) anthracenes/phenanthrenes, pyrene/fluoranthene, methylpyrenes/benzofluorenes, chrysene, benz[a]anthracene, methylchrysenes, methylbenz[a]anthracenes, perylene, benzo[a]pyrene, dibenz[a,kl]anthracene, dibenz[a,h]anthracene, and combinations thereof, the SVOC concentration ranges from between 10 parts per million by volume to 1,000 parts per million by volume on a dry basis;

(e) a hydrogen chloride concentration ranging from between greater than 0 parts per million by volume to 1,000 parts per million by volume on a dry basis; and

(f) a hydrogen sulfide concentration ranging from between greater than 0 parts per million by volume to 1,000 parts per million by volume on a dry basis.

17. A method of producing Fischer-Tropsch products, comprising:

(a) providing a source of unconditioned syngas;

(b) after step (a), hydrocarbon reforming the unconditioned syngas with an oxidant source to generate additional hydrogen and carbon monoxide and produce a syngas of improved quality, wherein the oxidant source includes one or more selected from the group consisting of carbon dioxide, steam, air, and oxygen;

(c) after step (b), cooling the syngas of improved quality;

(d) after step (c), removing at least a portion of the steam from the syngas of improved quality;

(e) after step (d), compressing the syngas of improved quality;

(f) after step (e), removing one or more volatile organic compounds from the syngas of improved quality;

(g) after step (f), removing ammonia from the syngas of improved quality, thereby producing an ammonia-depleted syngas of improved quality;

(h) after step (g), removing carbon dioxide from the ammonia-depleted syngas of improved quality, thereby forming an ammonia-and-carbon-dioxide-depleted syngas of improved quality; and

(i) after step (h), introducing the ammonia-and-carbon-dioxide-depleted syngas of improved quality to a Fischer-Tropsch (FT) catalytic synthesis process and generating Fischer-Tropsch products including at least a Medium Fraction Fischer-Tropsch Liquid (MFFTL) and wax;

wherein;

the unconditioned syngas in step (a) includes;

(I) a carbon monoxide concentration ranging from between 5 volume percent to 35 volume percent on a dry basis;

(II) a hydrogen concentration ranging from between 20 volume percent to 60 volume percent on a dry basis;

(III) one or more volatile organic compounds (VOC) selected from the group consisting of benzene, toluene, phenol, styrene, xylene, cresol, and combinations thereof, the VOC concentration ranges from between 500 parts per million by volume to 10,000 parts per million by volume on a dry basis; and

(IV) one or more semi-volatile organic compounds (SVOC) selected from the group consisting of indene, indan, napthalene, methylnapthalene, acenapthylene, acenapthalene, anthracene, phenanthrene, (methyl-) anthracenes/phenanthrenes, pyrene/fluoranthene, methylpyrenes/benzofluorenes, chrysene, benz[a]anthracene, methylchrysenes, methylbenz[a]anthracenes, perylene, benzo[a]pyrene, dibenz[a,kl]anthracene, dibenz[a,h]anthracene, and combinations thereof, the SVOC concentration ranges from between 10 parts per million by volume to 1,000 parts per million by volume on a dry basis.

18. The method according to claim 17, comprising, in step (f),

removing one or more volatile organic compounds from the syngas of improved quality with an adsorbent, the adsorbent being one or more selected from the group consisting of styrene based polymeric adsorbents, molecular sieves, zeolites, catalyst materials, silica gel, alumina, and activated carbon materials.