System for syngas clean-up

Patent metadata

Field	Value
Publication number	US-9783417-B2
Application number	US-201514939040-A
Country	US
Kind code	B2
Filing date	Nov 12, 2015
Priority date	Sep 27, 2011
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

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.

First claim

What is claimed is:

1. A syngas clean-up system for processing unconditioned syngas having solids and semi-volatile organic compounds (SVOC) therein, comprising:
a hydrocarbon reformer ( 8000 ) connected to a source of unconditioned syngas and operated to output an improved quality syngas;
a semi-volatile organic compound (SVOC) removal system positioned downstream of the hydrocarbon reformer ( 8000 ), the SVOC removal system comprising at least one scrubber ( 8100 , 8125 ) and configured to output a first depleted syngas stream having a reduced amount of solids and SVOCs relative to the unconditioned syngas;
at least one syngas compressor ( 8600 ) positioned downstream of the scrubber and configured output a compressed first depleted syngas stream;
a volatile organic compound (VOC) separation system positioned downstream of the syngas compressor, the VOC separation system comprising at least one adsorber and configured to output a second depleted syngas stream which has a reduced amount of VOC relative to the compressed first depleted syngas stream;
at least one carbonyl sulfide hydrolysis bed ( 8875 ) positioned downstream of the VOC separation system and configured to remove carbonyl sulfide to produce a third depleted syngas stream which has a reduced amount of carbonyl sulfide relative to the second depleted syngas stream; and
at least one sulfur guard bed ( 8900 ) positioned downstream of the carbonyl sulfide hydrolysis bed and configured to remove at least one sulfur compound to produce a sulfur-depleted syngas stream which has a reduced amount of sulfur relative to the second and third depleted syngas streams.

2. The system according to claim 1 , wherein the SVOC removal system comprises:
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.

3. The system according to claim 2 , wherein the SVOC removal system further comprises:
an SVOC separation system (SVOC- 1 ) configured to receive said SVOC and solvent removed through the candle filter, and output a first stream of SVOC and a second stream of SVOC-depleted solvent.

4. The system according to claim 3 , wherein the SVOC removal system further comprises:
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 ).

5. The system according to claim 1 , wherein the SVOC removal system comprises:
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 separation device arranged to receive the third mixture and separate the solids from the SVOC and solvent, and output an SVOC-laden solvent.

6. The system according to claim 5 , wherein the SVOC removal system further comprises:
an SVOC separation system (SVOC- 1 ) configured to receive said SVOC-laden solvent and output a first stream of SVOC and a second stream of SVOC-depleted solvent.

7. The system according to claim 5 , wherein the SVOC removal system further comprises:
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 ).

8. The system according to claim 1 , further comprising:
a chlorine scrubber ( 8500 ) positioned downstream of the at least one scrubber and upstream of the syngas compressor ( 8600 );
wherein the chlorine scrubber ( 8500 ) is configured to reduce an amount of chlorine present in the first depleted syngas stream.

9. The system according to claim 8 , further comprising:
a sulfur scrubber ( 8550 ) positioned downstream of the chlorine scrubber ( 8500 ) and upstream of the syngas compressor ( 8600 );
wherein the chlorine scrubber ( 8500 ) is configured to reduce an amount of chlorine present in the first depleted syngas stream.

10. The system according to claim 9 , further comprising:
a particulate filter ( 8575 ) positioned downstream of the sulfur scrubber ( 8550 ) and upstream of the syngas compressor ( 8600 );
wherein the particulate filter is configured to reduce an amount of particulates present in the first depleted syngas stream.

11. The system according to claim 1 , further comprising:
a carbon dioxide separator ( 8925 ) positioned downstream of the at least one carbonyl sulfide hydrolysis bed ( 8875 );
wherein the carbon dioxide separator ( 8925 ) is configured to reduce an amount of carbon dioxide in the third depleted syngas stream.

12. The system according to claim 11 , wherein at least a portion of the carbon dioxide removed from the third depleted syngas stream is conveyed to a syngas generator upstream of the hydrocarbon reformer ( 8000 ) for use in generating additional unconditioned syngas.

13. The system according to claim 1 , further comprising:
an ammonia scrubber ( 8800 ) positioned downstream of the VOC separation system and upstream of the at least one sulfur guard bed ( 8900 );
a metal guard bed ( 8775 ) positioned downstream of the VOC separation system and upstream of the at least one sulfur guard bed ( 8900 );
a carbon dioxide separator ( 8925 ) positioned downstream of all three of the ammonia scrubber ( 8800 ), the metal guard bed ( 8775 ) and the carbonyl sulfide hydrolysis bed ( 8875 );
wherein the ammonia scrubber ( 8800 ) is configured to reduce an amount of ammonia present in the second depleted syngas stream;
wherein the metal guard bed ( 8775 ) is configured to reduce an amount of metal present in the second depleted syngas stream; and\
wherein the carbon dioxide separator ( 8925 ) is configured to reduce a

Assignees

• Thermochem Recovery Int Inc

Inventors

• Chandran Ravi
• Leo Daniel Michael
• Freitas Shawn Robert
• Newport Dave G
• Whitney Hamilton Sean Michael
• Burciaga Daniel A

Classifications

• B01D53/1406

  Multiple stage absorption · CPC title

• B01D47/10

  Venturi scrubbers · CPC title

• C01B2203/048

  the impurity being an organic compound · CPC title

• B01D2259/402

  using two beds · CPC title

• B01D53/1487

  Removing organic compounds · CPC title