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H2S removal from air 1
- Thread starter danzberg
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DeltaCascade
Chemical
Try checking out bio-filters .. on the web, etc. It is fairly well established technology.
Good luck.
Good luck.
The basic solution to H2S (as well as mercaptans, dimethly sulfide, dimethyl disulfide, etc.) is to oxidize the sulfide to sulfate. This has been done conventionally in a packed tower (wet scrubber) using caustic and hypochlorite (or other oxidizing agent) as the scrubbing liquor. At pH 9 the H2S is solubolized and the oxidizing agent then does its work. As the other reply indicates - biological systems have been gaining favor because rather than buy the chemicals just mentioned, a naturally occuring bloom of Thiobacillus (several species exist) will develop in a properly designed and maintained biotrickling system and the bugs will convert sulfides to sulfates in their life process for free. Bio systems operate at much lower gas velocities than chemical scrubbers, so system size for a large air flow will require a large vessel or probably multiple vessels. At a pump station - where the air flow is low - a bio system may be ideal - low cost to fabricate, can be automated - no hazardous chemicals needed. More information about both wet scrubbing and biotrickling odor control can be found on our web site
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I understand the alternatives described by Deltacasacade and jilmed.
There is a little problem to use these alternatives.
We cannot confine the odor source to use a biofilter or srcubber.
These odor sources are dispersed around the site and each one needs an odor control.
Other place with H2S is the sewagwe pumping stations located inside houses neighbourhood.
Harold
There is a little problem to use these alternatives.
We cannot confine the odor source to use a biofilter or srcubber.
These odor sources are dispersed around the site and each one needs an odor control.
Other place with H2S is the sewagwe pumping stations located inside houses neighbourhood.
Harold
Another option to consider is carbon scrubbing. At many of our wastewater pump stations and some of our smallest plants we have small (55-gallon drum) to medium sized carbon systems in use. The odors are non-detectable and we infrequently have to change out the carbon. Many of our systems are using Calgon's Centaur carbon which can utilize water washing to extend the life, (though we haven't tried yet).
Is there any possibilities for chemical (corrosion inhibitor)containing thioglycolic acid and/or imidiazoline thioglycolate to produce hydrogen sulfide?
In what condition would it be decomposed (pressure, temperature)? How long would it be decomposed and to what extent is the decomposition (ie.certain concentration of thiolgycolic acid and/or imidiazoline thioglycolate will produce how much h2s)?
please be kind to reply the answer at piglet275@lycos.com
Thank you very much.
In what condition would it be decomposed (pressure, temperature)? How long would it be decomposed and to what extent is the decomposition (ie.certain concentration of thiolgycolic acid and/or imidiazoline thioglycolate will produce how much h2s)?
please be kind to reply the answer at piglet275@lycos.com
Thank you very much.
waterexpert
Chemical
Confining the odour is commonly done at locations just such as you describe by using GRP covers. I have extensive experience of such an approach. These covers may them be connected using fans and ducting to a central location.
This location may have biological, chemical or catalytic chemical scrubbers, carbon filters, activated alumina beds,or ozone contactors.
Alternatively, it is possible to dissolve the H2S by increasing the pH, or inhibit H2S production using nitrate or other proprietary chemicals.
There are any numbers of firms here in the UK offering such services. I assume the US is no different.
This location may have biological, chemical or catalytic chemical scrubbers, carbon filters, activated alumina beds,or ozone contactors.
Alternatively, it is possible to dissolve the H2S by increasing the pH, or inhibit H2S production using nitrate or other proprietary chemicals.
There are any numbers of firms here in the UK offering such services. I assume the US is no different.
You might consider using a smaller in vessel biofilter for the sewage stations in the neighborhoods. The City of Portland (Oregon) has one on a sewage station where there were previously complaints. Check out They have low flow biofilters.
I would definatly consider ozone as an alternative. In the degassing of odors at wet wells/ collection stations it is a natural. The use on scrubbers has also been done. For more information go to our web site at
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- #10
Sorry for late response. The best way, in terms of cost and convenience, is to inhibit its biological formation in the collection system, or to scavenge the H2S while its still in the water. H2S of 1 ppm in water will yield up to 200 ppm in the air, so eliminating in the water is the cheapest way.
Bt the way, don't forget how expensive scrubbers and biofilters are, and the electricity for these large blowers must be considered when looking at total cost of ownership.
More questions, email me.
Bt the way, don't forget how expensive scrubbers and biofilters are, and the electricity for these large blowers must be considered when looking at total cost of ownership.
More questions, email me.
Another way of treating H2S in the gas phase is to use BioTRickling Filters, a form of biological scrubber.
Often when you remove the H2S you will find other low odour concentration compounds that produce an offensive smell, so you might need to consider polishing technologies such as Biofilters or Activated carbon to remove these components (such as dimethyl sulphide, dimethyl disulphide and other VOCs).
Dosing the sewer is probably more effective as a corrosion control & asset management tool, rather than odour control. You need to be careful of not affecting sewerage quality & you are also assuming all the odour is H2S.
As mentioned above if the odour is complex sulphide, nitrogen or VOC based then dosing may not be the whole solution.
Hope this helps
If you would like more advice contact Clean TeQ in Australia,
ctairman
Often when you remove the H2S you will find other low odour concentration compounds that produce an offensive smell, so you might need to consider polishing technologies such as Biofilters or Activated carbon to remove these components (such as dimethyl sulphide, dimethyl disulphide and other VOCs).
Dosing the sewer is probably more effective as a corrosion control & asset management tool, rather than odour control. You need to be careful of not affecting sewerage quality & you are also assuming all the odour is H2S.
As mentioned above if the odour is complex sulphide, nitrogen or VOC based then dosing may not be the whole solution.
Hope this helps
If you would like more advice contact Clean TeQ in Australia,
ctairman
As related byOZGE, Zeolites work very well , check out " web site, they are building trial scrubbers using Zeolite, with excellent results.
EngineeringManger
Mechanical
Hi there,
There are alternative low cost / non hazardous solutions to your problem and specifically to “open space” odor control.
Regards - Allen
There are alternative low cost / non hazardous solutions to your problem and specifically to “open space” odor control.
Regards - Allen
EngineeringManger
Mechanical
To remove H2S from the air - from 5ppb to 50000 ppm (inside process vessels & tanks - have a look at the site
If you are still in doubt please feel free to contact me at (713) 907 2088 - have lots of experience with "worker environment" projects, including process & toxic odors removal and elimination of nuisance odor complaints. I am not operating as a consultant thus my advise is free.
If you are still in doubt please feel free to contact me at (713) 907 2088 - have lots of experience with "worker environment" projects, including process & toxic odors removal and elimination of nuisance odor complaints. I am not operating as a consultant thus my advise is free.
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