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In our company we plan to create a large-scale hydrotreating pilot plant for catalyst testing. Our purpose in creating the pilot plant is treating various hydrocarbon feeds including naphtha, kerosene and diesel with 500 - 2500 ppm of sulfur. This setup will be used for catalyst testing and process design at higher capacity.
Our intended set-up should have a reactor with 15-20 liters for the catalytic bed and could operate at pressures above 250 bar and temperatures above 650 C.
For catalytic reactor design, L/D ratio is an important parameter and various considerations and limitations for the industrial scale found in texts can be used for estimation of this parameter. For the pilot scale many of these conditions can't be used. Are there any documents or references at pilot scale?
 
Answers
13/05/2020 A: RAUL FLORES, PDVSA INTEVEP, fraulf@hotmail.com
Hi,

650 ÂșC -and above!- looks like a very high temperature: some catalyst matrices start sintering (area loss) at temperatures below that figure. On the other hand start the migration and the transformation of the active phase also. You need to read a lot to not spend your resources, mainly time which you can't buy.

Regards,
13/05/2020 A: Ed Ouwerkerk, Catalyst Intelligence Sarl, ouwerkerk@catalyst-intelligence.com
For trickle flow reactors L/D is not a design parameter, but D/dp and L/dp are..
Pls check out the extensive design guidelines by S. Sie et al., "Scale-up and scale-down of trickle bed processes" in Reviews in Chem. Eng., Vol 14(3), pp.203-252 (50 pages!).