4 replies to this topic

[johneyissac98]

Hi everyone,
In our plant we have a stripper column which separates C7 to C17 the O/H contains C7 to C10 and the water is injected because of the presence of H2S (i,e 200ppm) and condensed in a fin fan exchanger.
My question is,
Why water is injected?
What happens when water is not injected ?
Does water and H2s form sulphuric acid (corrosive) if so why are we injecting water that help’s corrosion?
Thank you in advance:)

Edited by johneyissac98, 19 January 2023 - 02:21 PM.

[PingPong]

You don't supply sufficient info to answer those questions. No PFD, no feed composition, no temperatures, no pressures, ......

 

In general: if a column feed contains H2S as well as some H2O (even if only traces) then often water is injected upstream the condenser to dilute the H2S that dissolves in the water. If in such case no water would be injected then the first drop of water that condenses inside the condenser would have a high H2S concentration and would be very corrosive to the condenser tubes.

 

Why water is injected in your column O/H I don't know (due to lack of more detailed info) but you should check the original design books to see whether it was included in the original design or not. If it was added later then find out who added it and why.

[shvet1]

Sulfide salts formation may be an issue. Depends on combination of pressure, temperature and NH3.

[johneyissac98]

Thank you @pingpong and @shvert1

Edited by johneyissac98, 23 January 2023 - 03:58 AM.

[SilverShaded]

Curious why you have H2S in heavy naphtha?

Edited by SilverShaded, 24 January 2023 - 04:00 AM.