1-Hexene process 3

[khokho99]

gents,
Good morning/evening ,We are working at 1-Hexene plant production. trimerization Ethelene with Chrome catalyst to produce 1-Hexene.
we faced lately issue , that upstream the CSTR reactor get plugged & that cause the catalyst flow came down , any suggestion & help.

thanks,

 

[Latexman]

What is the usual duration between pluggings?


Good Luck,
Latexman

 

[khokho99]

Good morning/evening ,
After injection the catalyst to CSTR reactor by positive displacement pumps ( almost 2 weeks the stroke increased to 100% & the catalyst flow came down to the minimum
the injection point to the CSTR reactor get plugged , any advice .

Thanks,

 

[Latexman]

Attach a drawing or sketch of "injection point" and show where/how it plugs.

Good Luck,
Latexman

 

[PS6788]

Hello kadiaa,

I'm assuming that the catalyst is some liquid phase and not a slurry? I would hazard to guess that your ethylene is polymerizing at the point where its mixing with the catalyst. Slurry can plug on its own. Check your operating conditions at the injection point. These types of reactions are notorious for fouling up equipment. It would also be helpful if you could provide more details.

 

[georgeverghese]

@ps6788,@latexman,
Though I know little of the configuration of this CSTR, this is my suspicion too. If this a single injection point, it may be located at a place where is poor mixing. There ought to be multiple injection points located in regions with high turbulence. We need to see a sketch or GA of this CSTR with injection point.
Presume this is an exothermic reaction - if so, are there hotspots in this CSTR ?

 

[khokho99]

Good morning/evening ,
Thank you all for your replied & support . we suspect there is some balance change for our catalyst amount ( Ethylene benzene + Aluminum alkyl + pyrrole + chrome) mixer that may cause this issue , still under troubleshooting . any body has experience with 1-Hexene process .

 

[georgeverghese]

How is the catalyst recovered? Can we see a PFD which includes catalyst recovery operation ? Looks like this is Chevron - Phillips process ?

 

[khokho99]

Good morning/ Evening georgeverghese ,
Actually we are not recovering the catalyst , we are kill it by using (2 ethyl hexanol ) due to ALUMUNIUM ALKYLE is pyrophoric .yes it is.

Thanks.

 

[khokho99]

I trayed to attached the information , but unfortunately I can't .