4 replies to this topic

[daraj]

Hi, for a quick sizing of mixed-phase reactors(such as say a trickle bed which has both liquid feed and a gas like hydrogen enteriong the reactor) I ma using LHSV values typically applied to this type of reaction from literature.

 

what I wanted to know was does the definition of LSHV include porosity? this is not clearly mentioned anywhere. Some say it doesn, some say it doesnt.

 

for example, in a lot of peer reviewed papers and articles, LHSV for  a particular reaction is mentioned as 5 hr-1.

 

So lets say i have a LIQUID feed flow rate of 5 m3/hr entering the reatcor. (Gas flow may be higher say 25 m3/hr)

 

so the bed volume = liquid flow rate/LHSV =  5/5 = 1 m3.

 

 now is this the bulk bed volume or just the volume occupied by the solid catalyst particles? if its the latter, i need to divide this volume further by voidage to get my bed volume.. what is the commonly accepted convention scentifically and industrially? i need this to quickly scale up a reactor based on data from literature for industrial operation.

 

any pointers to reactor design of this type based on LHSV is welcome. I also need to know how to figure in the gas velocity in sizing the bed and the reactor volumes. (reactor volume is > bed volume)

 

Thanks

[breizh]

Hi,

It seems there is a consensus on the definition: 

http://www.eptq.com/...24-d45bfaef8c64

my 2 cents, after asking my best friend Google

Breizh 

[Bobby Strain]

Ask your catalyst supplier.

 

Bobby

[daraj]

Breizh, thanks, although the lin you have given as inputs on everything except reactor volume definition. From what i gathered looks like the bulk bed volume(including voidage) is considered for LHSV, not just the catalyst volume, typically.

[breizh]

Hi,

Yes, I believe so, should include the void of the catalyst bed,

EDIT: not sure!

http://pu.edu.pk/ima...20-Feb-2014.pdf

 

As pointed out why don't you call or drop an email to catalyst vendor to get a final answer? In any case you will have to make the call.

BTW did you check the technical data sheet of the catalyst?

Breizh