2 replies to this topic

[Deckel]

Hi there,

I am trying to recover some MEG, problably from a gas/oil refinary process, it comes with that awfull mercaptan smell. We already tried hydrogen peroxide and iron catalyst, hypoclorite, activated coal, before and after the drying and distillation process with no positive results. Even the seal water from the liquid ring vacuum pump  gets contaminated with that strong smell.
Has anyone dealt with this process? Any help is appreciated!

[Art Montemayor]

That awful odor that you smell could be hydrogen sulfide - as well as mercaptans.  If so, I wouldn't mess with it.

What makes you so certain that it is only mercaptans that are the contaminants?  Have you made a detailed and specific analysis of the MEG?

 

The way to strip the gas(es) from the MEG would be to use a stripping process - and even then you probably couldn't remove ALL the undesired H₂S - the smelling threshold of this gas is so low that our noses can detect ppms (and thank God for that).

 

I believe you've got a situation where you can't justify any purification of the quantity of MEG that you have in stock - although you don't state the total MEG quantity.

[Deckel]

Thanks for the reply Art, i am not sure about the contaminants, could be both. We got about 30 tons in stock and there is a about 150 tons available. We already distilled about 25 tons and we managed to sell it (after the whole process of distillation, oxidation and activated coal filtration), the odor is reduced, but for me is not satisfying. The worst is the smell on the equipment in contact with the solution (reactor, tanks, water from the vacuum pump). We are not using any kind of mist eliminator or cyclone separator on the column, maybe is dragging too much contaminants to the distilled MEG?