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[RodEsc]

Hi, I am currently designing a high temperature water gas shift reactor and I would like to ask a few questions. Some of the conditions are at the end of the topic.

I assumed plug flow in my calculations on Excel. Comparing the results with the ones obtained on HYSYS, they were quite similar. However HYSYS also uses plug flow model. Now that I have the necessary volume for my reactor, I don`t know how to manage its dimension in order to make this plug flow model "real". Other assumptions include no temperature and concentration gradients between the catalyst and gas (I suppose there is enough turbulence to provide this).

Can you give any hint about the Length to diameter ratio? I know that designs with high L/D ratios are closer to this plug flow model, but I am concerned about other issues as well. I am assuming flat velocity profiles and no radial gradients of mass and heat, what cannot be true in reactors with small diameters. Pressure drop is not a problem in my process. The mechanical issue of having a really tall reactor with a small diameter concerns me too.

The other questions regard reactor internals. If a bed is fixed using support balls (alumina in this case), is it necessary to have a support grid as well? Also, I would like to know how to choose an inlet distributor, outlet grid and nozzles. 

Finally, do you know where can I found ASME data for steels? I have to calculate the reactor thickness and I need some data for this (I will use 0,5Mo or 1,0Cr0,5Mo steel).

 

Inlet/outlet temperatures - 350C/490C

Pressure: 40 bar

Reactor type: packed bed

Calculated volume: 0,884m3

Catalyst weight: ~1300kg

Catalyst size: cylinder of 6x6mm

Volumetric flow at the intlet: 314,6m3/h

 

Thanks!!