System for syngas clean-up of semi-volatile organic compounds

• US 9,845,240 B2
• Filed: 11/12/2015
• Issued: 12/19/2017
• 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): WARTALOWICZ, PAUL A
• Application Number:
  US14/939,006
• Publication Number:
  US 20160059176A1
• Time in Patent Office: 768 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 system for removing solids and semi-volatile organic compounds (SVOC) from unconditioned syngas having steam contained therein, the unconditioned syngas having a first temperature above a SVOC condensation temperature, the system comprising:

a venturi scrubber (8100) configured to receive the unconditioned syngas, solvent and water and output an intermediate SVOC-depleted syngas containing steam together with a first mixture comprising SVOC, solids, solvent and water;

a char scrubber (8125) configured to receive the intermediate SVOC-depleted syngas containing steam and the first mixture, and separately output;

(i) a first depleted syngas stream which has a reduced amount of SVOC relative to the unconditioned gas stream, and (ii) a second mixture comprising SVOC, solids, solvent and water;

a decanter (8275) configured to receive the second mixture and separate the water within the second mixture based upon immiscibility so that the SVOC, solids and solvent collect together to form a third mixture separate from the water within the decanter, the decanter further configured to separately output the water and the third mixture; and

a vessel (8300) arranged to receive the third mixture, the vessel having at least one liquid phase candle filter and a vessel bottom provided with a drain port;

wherein;

the candle filter is capable of operating so that;

(i) the solids agglomerate on a surface of the candle filter and form a filter cake, and (ii) the SVOC and solvent are removed through the candle filter, and

the drain port is suitable for removing filter cake therethrough.

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

an SVOC separation system (SVOC-1) configured to receive SVOC and solvent from the candle filter, and output a first stream of SVOC and a second stream of SVOC-depleted solvent.

3. The system according to claim 2, wherein the SVOC separation system comprises:

a flash tank (8350) configured to receive SVOC and solvent from the candle filter, flash the SVOC from the solvent, and output SVOC flash vapors and the second stream of SVOC-depleted solvent;

a condenser (8400) configured to receive the SVOC flash vapors and output the second stream of SVOC.

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

a SVOC vacuum system (8425) connected to the flash tank (8350) via the condenser (8400) and configured to lower a pressure within the flash tank to aid in separation of the SVOC vapors from the second stream of SVOC-depleted solvent.

5. A system for processing unconditioned syngas, comprising:

a system according to claim 1 for removing solids and semi-volatile organic compounds (SVOC) (D-1) from the unconditioned syngas to thereby form a first depleted syngas stream;

a compressor (8600) configured to receive and compress the first depleted syngas stream;

a pressure swing adsorption system (VOC-1) comprising parallel first and second microchannel heat exchange adsorbers (8625A &

8625B) capable of being operated such that while the first heat exchange adsorber (8625A) is in an adsorption mode, the second heat exchange adsorber is in a regeneration mode (8625B), the pressure swing adsorption system (VOC-1) configured to receive the compressed first depleted syngas stream and separately output;

(i) a second depleted syngas stream which has a reduced amount of volatile organic compounds (VOC) relative to the compressed first depleted syngas stream, and (ii) volatile organic compounds (VOC); and

at least one bed configured to receive the second depleted syngas stream and remove at least one sulfur compound therefrom to produce a sulfur-depleted syngas stream which has a reduced amount of sulfur relative to the second depleted syngas stream.

6. The system for processing unconditioned syngas according to claim 5, wherein:

the at least one bed configured to receive the second depleted syngas stream comprises either;

(a) an adsorption bed (8900) alone;

or

(b) a hydrolysis bed (8875) and an adsorption bed (8900) arranged in series.

7. A system for processing unconditioned syngas, comprising:

a system according to claim 1 for removing solids and semi-volatile organic compounds (SVOC) (D-1) from the unconditioned syngas to thereby form the first depleted syngas stream;

a compressor (8600) configured to receive and compress the first depleted syngas stream;

an aromatic hydrocarbon fluidized adsorption bed (8700) configured to receive the compressed first depleted syngas stream and separately output;

(i) a second depleted syngas stream which has a reduced amount of volatile organic compounds (VOC) relative to the compressed first depleted syngas stream, and (ii) VOC-laden sorbent, in combination with a regeneration fluidized bed (8725) configured to receive the VOC-laden sorbent from the aromatic hydrocarbon fluidized adsorption bed (8700) and separately output the VOC and the sorbent; and

at least one bed configured to receive the second depleted syngas stream and remove at least one sulfur compound therefrom to produce a sulfur-depleted syngas stream which has a reduced amount of sulfur relative to the second depleted syngas stream.

8. The system for processing unconditioned syngas according to claim 7, wherein:

the at least one bed configured to receive the second depleted syngas stream comprises either;

(a) an adsorption bed (8900) alone;

or

(b) a hydrolysis bed (8875) and an adsorption bed (8900) arranged in series.

9. A system for processing unconditioned syngas, comprising:

a system according to claim 1 for removing solids and semi-volatile organic compounds (SVOC) (D-1) from the unconditioned syngas to thereby form a first depleted syngas stream;

a compressor (8600) configured to receive and compress the first depleted syngas stream;

an aromatic hydrocarbon fixed adsorption bed (8625) configured to receive the compressed first depleted syngas stream and separately output;

(i) a second depleted syngas stream which has a reduced amount of volatile organic compounds (VOC) relative to the compressed first depleted syngas stream, and (ii) VOC-laden sorbent for regeneration into a VOC stream and a sorbent stream, and

at least one bed configured to receive the second depleted syngas stream and remove at least one sulfur compound therefrom to produce a sulfur-depleted syngas stream which has a reduced amount of sulfur relative to the second depleted syngas stream.

10. The system for processing unconditioned syngas according to claim 9, wherein:

the at least one bed configured to receive the second depleted syngas stream comprises either;

(a) an adsorption bed (8900) alone;

or

(b) a hydrolysis bed (8875) and an adsorption bed (8900) arranged in series.

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

an SVOC separation system (SVOC-1) configured to receive said SVOC-laden solvent and output an SVOC-depleted solvent.

12. The system according to claim 11, wherein the SVOC separation system comprises:

an SVOC sorptive separator (8475) configured to receive and separate filtered SVOC-laden solvent into a first stream comprising said SVOC-depleted solvent and a second stream comprising SVOCs; and

an SVOC condenser (8400) configured to condense said second stream comprising SVOCs.

13. The system according to claim 12, wherein the SVOC sorptive separator (8475) comprises a membrane or a packed bed of adsorbent.

14. The system according to claim 11, wherein the SVOC separation system comprises:

an SVOC flash tank (8350) configured to receive and separate SVOC-laden solvent into a first stream comprising said SVOC-depleted solvent and a second stream comprising SVOCs; and

an SVOC condenser (8400) configured to condense said second stream comprising SVOCs.

15. The system according to claim 14, further comprising:

an SVOC flash tank heat exchanger (8325) configured to receive and heat said SVOC-laden solvent before said SVOC-laden solvent is received by said SVOC flash tank (8350); and

a solvent cooler (8375) configured to receive and cool said SVOC depleted solvent.

16. The system according to claim 11, further comprising

a first recirculation solvent line (32) configured to convey a first portion of the SVOC-depleted solvent to the venturi scrubber;

and

a second recirculation solvent line (40) configured to convey a second portion of the SVOC-depleted solvent to the char scrubber.

17. The system according to claim 1, further comprising:

a recirculation loop configured to backflush the candle filter using a portion of the SVOC and solvent removed through the candle filter.

18. The system according to claim 1, further comprising:

a heat exchanger (8150) configured to receive water from the decanter (8275) and to provide water to both the venturi scrubber (8100) and the char scrubber (8125).

19. A system for removing solids and semi-volatile organic compounds (SVOC) from unconditioned syngas having steam contained therein, the unconditioned syngas having a first temperature above a SVOC condensation temperature, the system comprising:

a venturi scrubber (8100) configured to receive the unconditioned syngas, solvent and water and output an intermediate SVOC-depleted syngas containing steam together with a first mixture comprising SVOC, solids, solvent and water;

a char scrubber (8125) configured to receive the intermediate SVOC-depleted syngas containing steam and the first mixture, and separately output;

(i) a first depleted syngas stream which has a reduced amount of SVOC relative to the unconditioned gas stream, and (ii) a second mixture comprising SVOC, solids, solvent and water;

a decanter (8275) configured to receive the second mixture and separate the water within the second mixture based upon immiscibility so that the SVOC, solids and solvent collect together to form a third mixture separate from the water within the decanter, the decanter further configured to separately output the water and the third mixture;

a heat exchanger (8150) configured to receive water from the decanter (8275) and to provide water to both the venturi scrubber (8100) and the char scrubber (8125); and

a separation device arranged to receive the third mixture and separate the solids from the SVOC and solvent, and output an SVOC-laden solvent.

20. A system for removing solids and semi-volatile organic compounds (SVOC) from unconditioned syngas having steam contained therein, the unconditioned syngas having a first temperature above a SVOC condensation temperature, the system comprising:

at least one scrubber (8100, 8125) configured to receive the unconditioned syngas and water, and separately output;

(i) a first depleted syngas stream which has a reduced amount of SVOC relative to the unconditioned gas stream, and (ii) a second mixture comprising at least solids and water;

a decanter (8275) configured to receive the second mixture and separate the solids from a least a portion of the water;

a heat exchanger (8150) configured to receive said a least a portion of the water from the decanter (8275) and return water to at least one scrubber; and

a separation device arranged to receive at least said solids separated by said decanter.

21. The system according to claim 20, wherein:

one or more SVOCs are included in the second mixture, and

the decanter receives said one or more SVOCs.