Suitable Antifoamer in Hydrocracker LPG Amine Contactor

[1906]

Last year we changed Amine in H2S ABosrber and LPG contactor in Hydrocracker complex from DEA to MDEA actually formulated MDEA. After changing-out, Hydrocracker LPG contactor foaming(and/or emulsion, whatever called) tendancy has been increased, so, we injected silicon type antifoamer continuously with the worry of C4 contamination by silicon and its heavy hydrocarbon. To avoid this, is there anybody knows about anti-foamer suitable for LPG contactor ?
And, if you guys know the reason, would you please give me good information to avoid faoming tendancy especially in mentioned LPG contactor?

 

[Jason5000]

If at all possible get the silicon out of your amine unit. Nalco and GE Betz both make polyglycol type antifoams that are likely better for not extracting to a large degree into your LPG, and they may help decrease equipment fouling rates too. Betz also has a couple of different chemicals they think are better than polyglycols. Max Amine 70B is the product for gas contactors, but there is one specific product for liquid/liquid absorbers too.

As for what causes foaming, that's a tougher nut to crack. For starters I'd try searching the forums here as there are some pretty good threads about amine foaming. In general clean amine doesn't foam. Particulate contamination can cause it; is your filtration working well? Hydrocarbon contamination can cause it; do you skim your flash drum and are you finding a lot oil when you skim your flash drum? Do you have a charcoal filter, and does it need changed out? Are you gas or liquid flow rates high? Its easy to mistake flooding for foaming. Over dosing silicon antifoam can contribute to foaming. These are some of the easy things to check, but certainly not a complete list.

Good luck.

 

[dcasto]

go to the huntsman chemicals site and join the forum there to. they have lots of papers to guide you.

Jason has you on a good start.

my question is why the change to a formulated amine for H2S removal?

 

[1906]

Thanks dcasto.
We changed to formulated MDEA to minimize corrosion and to save steam.