Treatment of Hydrogen Sulfide Gas Under Aerobic Conditions

• US 20180104644A1
• Filed: 10/12/2017
• Published: 04/19/2018
• Est. Priority Date: 10/14/2016
• Status: Active Grant

• Current Assignee: Streamline Innovations, Inc.
• Original Assignee: Biosystems Consulting Inc.
• Inventors: Cox, JR., Henry Wilmore
• Granted Patent: US 10,639,585 B2
• Time in Patent Office: Days
• CPC Class Codes: B01D 2251/102 Oxygen
• CPC Class Codes: B01D 2251/106 Peroxides
• CPC Class Codes: B01D 2251/11 Air
• CPC Class Codes: B01D 2251/90 Chelants
• CPC Class Codes: B01D 2257/304 Hydrogen sulfide
• CPC Class Codes: B01D 2258/06 Polluted air
• CPC Class Codes: B01D 53/1493 Selection of liquid materials for use as absorbents
• CPC Class Codes: B01D 53/52 Hydrogen sulfide
• CPC Class Codes: B01D 53/78 with gas-liquid contact
• CPC Class Codes: B01D 53/96 Regeneration, reactivation or recycling of reactants
• CPC Class Codes: C01B 13/0211 Peroxy compounds
• CPC Class Codes: C07F 15/025 without a metal-carbon linkage

Abstract

Certain exemplary embodiments can provide a system, machine, device, manufacture, and/or composition of matter adapted for and/or resulting from, and/or a method for, activities that can comprise and/or relate to contacting an aerobic contaminated gas stream with a solution comprising approximately Ferric MGDA, the aerobic contaminated gas stream comprising hydrogen sulfide.

Claims

1. A method for treating an aerobic contaminated gas stream, comprising:

performing a first plurality of activities, the first plurality of activities comprising;

contacting the aerobic contaminated gas stream with a clean aqueous solution comprising approximately 0.5% Ferric MGDA to approximately 100% Ferric MGDA, the aerobic contaminated gas stream comprising air and comprising hydrogen sulfide at a concentration in the air of approximately 5 ppm or higher;

forming bonds between sulfide formed from the hydrogen sulfide and the iron in the Ferric MGDA to create;

an aerobic clean gas stream having a hydrogen sulfide concentration of 3.5 ppm or less; and

a dirty aqueous solution comprising sulfide saturated ferro MGDA;

mixing the dirty aqueous solution with an oxidant; and

via a reaction with the oxidant, breaking the bonds between the sulfide and the Ferric MGDA to form elemental sulfur mixed with a re-activated solution comprising re-activated Ferric MGDA;

separating the elemental sulfur from the re-activated solution to form a substantially hydrogen-sulfide-free solution; and

re-cycling the substantially sulfide-free solution to serve as the clean aqueous solution.

2. The method of claim 1, wherein:

each of the first plurality of activities occurs in a common vessel.

3. The method of claim 1, further comprising:

repeating the first plurality of activities.

4. The method of claim 1, further comprising:

repeating the first plurality of activities without introducing additional Ferric MGDA to the clean aqueous solution.

5. The method of claim 1, wherein the first plurality of activities further comprises:

causing flow of the aerobic contaminated gas stream into the vessel.

6. The method of claim 1, wherein:

said contacting comprises bubbling the aerobic contaminated gas stream through the clean aqueous solution.

7. The method of claim 1, wherein:

said contacting comprises blowing the aerobic contaminated gas stream into the clean aqueous solution.

8. The method of claim 1, wherein:

said contacting comprises spraying the clean aqueous solution into the aerobic contaminated gas stream.

9. The method of claim 1, wherein:

said contacting comprises dripping the clean aqueous solution into the aerobic contaminated gas stream.

10. The method of claim 1, wherein:

the clean aqueous solution has a pH of 5.9 or higher.

11. The method of claim 1, wherein:

the clean aqueous solution has a pH of 8 or higher.

12. The method of claim 1, wherein:

the oxidant is a peroxide.

13. The method of claim 1, wherein:

the oxidant is oxygen within the aerobic contaminated gas stream.

14. The method of claim 1, wherein:

the oxidant is oxygen.

15. The method of claim 1, wherein:

the oxidant is atmospheric oxygen.

16. A method comprising:

in a substantially aerobic treatment zone of a vessel, reacting reactants comprising a ferro MGDA and an aerobic contaminated gas stream, the aerobic contaminated gas stream comprising air mixed with hydrogen sulfide, the hydrogen sulfide present at a concentration of at least 5 ppm, wherein;

reaction products of the reacting comprise;

a spent ferro MGDA that comprises iron saturated with sulfide; and

a clean gas stream having a concentration of hydrogen sulfide of no greater than 3.5 ppm;

a content of the treatment zone is actively maintained at a pH of between approximately 5.9 and approximately 10.

17. The method of claim 16, wherein:

the aerobic contaminated gas stream remains in contact with the ferro MGDA for at least 2.5 seconds.

18. The method of claim 16, wherein:

the ferro MGDA is recirculated at a rate of at least 0.055 gallons of ferro MGDA per cubic foot of the aerobic contaminated gas stream.