Method and apparatus for reactive gas remediation

Patent metadata

Field	Value
Publication number	US-9227156-B2
Application number	US-201314078520-A
Country	US
Kind code	B2
Filing date	Nov 12, 2013
Priority date	Nov 9, 2012
Publication date	Jan 5, 2016
Grant date	Jan 5, 2016

Abstract

Disclosed are methods, materials, apparatus and systems for removing or suppressing ambient levels of reactive gas contaminants, particularly acidic gases, using particles of zeolite, sepiolite or other suitable carrier material impregnated with at least one treatment compound selected to react with the acidic gas(es). The methods involve contacting a contaminated gas stream with the impregnated carrier materials whereby at least a portion of the reactive gases contacts the treatment compound and reacts, thereby consuming the reactive gas molecules.

First claim

We claim:

1. A method for reducing acidic gas contamination, the method comprising:
directing a feed gas stream containing a pretreatment concentration of an acidic gas compound onto carrier particles, the carrier particles having a surface supporting a treatment compound; and
reacting a portion of the acidic gas compound with the treatment compound under conditions whereby the portion of the acidic gas compound is consumed to produce a treated gas stream,
wherein the acidic gas compound is selected from the group consisting of hydrogen cyanide, hydrogen sulfide, hydrochloric acid, hydrogen fluoride, hydrogen iodide, hydrogen bromide, nitric acid vapor, chlorine, carbon disulfide, mercaptans and mixtures thereof.

2. The method for reducing acidic gas contamination according to claim 1 , wherein:
when the portion of the acid gas compound is consumed, it further produces a reaction product gas that is less hazardous than the acidic gas compound, and
the reaction product gas is released into the treated gas stream.

3. The method for reducing acidic gas contamination according to claim 2 , wherein:
the reaction product gas is chlorine dioxide.

4. The method for reducing acidic gas contamination according to claim 2 , wherein:
the reaction product gas is released at a concentration below the pretreatment concentration of the acidic gas compound.

5. The method for reducing acidic gas contamination according to claim 2 , wherein:
a portion of the reaction product gas released into the treated gas stream reacts with a second contaminant compound in the treated gas stream.

6. The method for reducing acidic gas contamination according to claim 5 , wherein:
the reaction product gas is chlorine dioxide.

7. The method for reducing acidic gas contamination according to claim 5 , further wherein:
the second contaminant compound is an organic compound.

8. The method for reducing acidic gas contamination according to claim 1 , wherein:
the carrier particles are selected from the group consisting of aluminosilicate minerals, hydrous aluminium phyllosilicates and mixtures thereof.

9. The method for reducing acidic gas contamination according to claim 1 , wherein:
the carrier particles are selected from the group consisting of zeolites, sepiolites and mixtures thereof.

10. The method for reducing acidic gas contamination according to claim 1 , wherein:
the treatment compound comprises sodium chlorite.

11. The method for reducing acidic gas contamination according to claim 1 , wherein:
the feed gas stream is directed over a combination of absorbent particles and the carrier particles.

12. The method for reducing acidic gas contamination according to claim 1 , wherein the acidic gas compound is selected from the group consisting of hydrogen cyanide, hydrogen fluoride, hydrogen iodide, hydrogen bromide, nitric acid vapor, chlorine, carbon disulfide, mercaptans and mixtures thereof.

13. The method for reducing acidic gas contamination according to claim 12 , wherein the acidic gas compound is selected from the group consisting of hydrogen cyanide, hydrogen fluoride, hydrogen iodide, hydrogen bromide, nitric acid vapor, chlorine, and mixtures thereof.

14. A system for reducing acidic gas contamination in an ambient gas, the system comprising:
a blower assembly for directing the ambient gas onto a plurality of carrier particles, the carrier particles having surfaces supporting a treatment compound;
a containment assembly for maintaining contact between the ambient gas and the treatment compound for a reaction period, the reaction period being sufficient to allow a portion of the acidic gas to react with the treatment compound under conditions whereby the portion of the acidic gas is consumed to form a treated gas stream; and
an output assembly for releasing the treated gas stream from the system,
wherein the acidic gas is selected from the group consisting of hydrogen cyanide, hydrogen sulfide, hydrochloric acid, hydrogen fluoride, hydrogen iodide, hydrogen bromide, nitric acid vapor, chlorine, carbon disulfide, mercaptans and mixtures thereof.

15. A system for reducing acidic gas contamination in an ambient gas according to claim 14 , further comprising:
a filter assembly for removing particles before the treated gas stream is released from the system.

16. A system for reducing acidic gas contamination in an ambient gas according to claim 14 , wherein:
the containment assembly has a configuration selected from the group consisting of fluidized beds, packed beds, filter cartridges and sachets.

17. A system for reducing acidic gas contamination in an ambient gas according to claim 14 , further comprising:
a gas monitoring system configured for determining an ambient concentration of the acidic gas; and
a control system configured for activating the blower assembly when the gas monitoring system detects an ambient concentration of the acidic gas above a high target level.

18. A system for reducing acidic gas contamination in an ambient gas according to claim 17 , wherein:
the control system is further configured for deactivating the blower assembly when the gas monitoring system detects an ambient concentration of the acidic gas below a low target level.

19. The method for reducing acidic gas contamination according to claim 14 , wherein the acidic gas compound is selected from the group consisting of hydrogen cyanide, hydrogen fluoride, hydrogen iodide, hydrogen bromide, nitric acid vapor, chlorine, carbon disulfide, mercaptans and mixtures thereof.

20. The method for reducing acidic gas contamination according to claim 19 , wherein the acidic gas compound is selected from the group consisting of hydrogen cyanide, hydrogen fluoride, hydrogen iodide, hydrogen bromide, nitric acid vapor, chlorine, and mixtures thereof.

21. A method for reducing acidic gas contamination, the method comprising:
directing a feed gas stream containing a pretreatment concentration of an acidic gas compound onto carrier particles, the carrier particles having a surface supporting a treatment compound; and
reacting a portion of the acidic gas compound with the treatment compound under conditions, whereby the portion of the acidic gas compound is consumed to produce a treated gas stream, and the reaction further produces chlorine dioxide that is released into the treated gas stream.

22. A method for reducing acidic gas contamination, the method comprising:
directing a feed gas stream containing a pretreatment concentration of an acidic gas compound onto carrier particles, the carrier particles having a surface supporting a treatment compound; and
reacting a portion of the acidic gas compound with the treatment compound under conditions, whereby the portion of the acidic gas compound is consumed to produce a treated gas stream,
wherein the carrier particles are selected from the group consisting of aluminosilicate minerals, hydrous aluminium phyllosilicates, zeolites, sepiolites and mixtures thereof.

Assignees

• Chemtreat Inc

Inventors

• Richardson John
• Gottschalk Kevin
• Mcilwaine Douglas

Classifications

• B01D2251/304

  of sodium · CPC title

• B01D53/40

  Acidic components (B01D53/44 takes precedence) · CPC title

• B01D53/44

  Organic components · CPC title

• B01D53/54 Primary

  Nitrogen compounds · CPC title

• B01D53/82

  with stationary reactants · CPC title