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We are working on a project to eliminate ammonia from sour gas stream to SRU in one of our refineries in order to improve SRU operation and beside to produce ammonium sulphate to be used as fertilizer. Instead double stage SWS, we are thinking in absortion with sulfuric acid in a tower and neutralization of acid excess etc. One way is to develop the process by own but we´d like to know first if someone know who is licensing this process or who is using this technology.
 
Answers
03/04/2012 A: S Banik, Centre for High Technology, sbdr@rediffmail.com
Destruction of NH3 in the SRU is conventional. It however reduces capacity of SRU by 10-15% of H2S conversion as 1 mole of NH3 is equivalent to 1.7 mole of H2S. Therefore scrubbing of sour gas with H2SO4 makes sense. DuPont has a patented process. It might have been commercialized.
13/05/2011 A: Egbert van Hoorn, Hocon B V, Egbertvh@hotmail.com
The two stage SWS process is (was) a licenced technology from Chevron.
I think that there are a number of reasons why you may not want to apply this.
Two stage stripping is twice as expensive as normal stripping.
Chevron hardly applies the technology in their own refineries.
There are some doubts about the separation.
We consider that it is cheaper to make the SRUs suitable for NH3 destruction
12/05/2011 A: keith bowers, B and B Consulting, kebowers47@gmail.com
The first responder has correctly identified current use of similar technology--which is licensed, and is successful.
The costs of H2SO4 and suitable contacting equipment will be substantial. The operating environment will be tremendously corrosive "dilute sulfuric acid is very hungry" and thorough investigation of ALL the organic and inorganic components in the acid gas stream is essential. Selection of metallurgy is going to be difficult, and the material VERY costly for certain. 'By-products' will likely contaminate the ammonium sulfate enough to render it unsuitable for use in crop fertilizer unless limited to a small portion of the final fertilizer mix.
Chevron's licensed WWT process is well proven, easy to operate, and has minimal risk of not working at or better than design efficiency.
If I were the Refinery Manager or Technology Manager who had to approve the R&D effort, I would insist right now on seeing COMPELLING potential economics for this new, unproven, complex and corrosive process you are contemplating
10/05/2011 A: Eric Vetters, ProCorr Consulting Services, ewvetters@yahoo.com
I am aware of a couple of refineries that take sour water stripper overhead to a plant that converts it to ammonium thiosulfate, which is used as fertilizer. I do not know if the technology is licensed or not.