5 replies to this topic

[m.ghaziasgar]

Hey everyone!
I’m simulating a DRM reactor in Aspen Plus (with RWGS and coke formation side reactions) using an LHHW kinetics model I found in the literature. The constants all seem correct, but my simulation results are way off—my conversion rates hover around 5%, while the experimental data is around 46%. I suspect this discrepancy is due to missing info in the experimental paper (I had to guess certain parameters).

I’m wondering if anyone has advice on which parameters to vary first or how to systematically approach finding a better fit. I have attached an image representing some reported parameters in the paper are fixed and match the experiment, so those I can’t change. Any tips or guidance would be greatly appreciated!

Thanks in advance!

 

[breizh]

Hi,

No image shared!

To share use the button "more replies option" , bottom right.

Breizh

[Pilesar]

1) Check your units of measure very carefully. Perhaps find someone else to check them also. We can be blind to our own mistakes.

2) Contact the author of the experimental paper and send them your calcs and questions.

[m.ghaziasgar]

These are experiment conditions and I am not able to change them:

1) pressure

2) temperature of the reactor

3) the feed ratio => (CO2/CH4/N2 = 1:1:0.22)

4) Reactor dimensions (Diameter = 0.03 m, height = 0.51m)

5) all the properties related to catalyst (e.g. catalyst loading, particle size and density)

6) the GHSV (2000 h^-1)

 

these 6 parameters are known but data about the feed flowrate is missing.

 

I think the reason that I am not getting results is because I don't define the GHSV properly. how can I validly define GHSV in CSTR model in Aspen Plus? (Should I define it through residence time spec?)

 

 

Attached Files

•  Screenshot 2025-01-08 150500.png   40.55KB   0 downloads

Edited by m.ghaziasgar, 08 January 2025 - 06:38 AM.

[PingPong]

I think the reason that I am not getting results is because I don't define the GHSV properly. how can I validly define GHSV in CSTR model in Aspen Plus? (Should I define it through residence time spec?)

CSTR ?

 

Shouldn't you use a Plug Flow Reactor model ?

[breizh]

Hi,

Agree with Ping Pong.

PFR,

example attached 

https://www.matec-co...che21_06002.pdf

Breizh