7 replies to this topic

[rifat]

Hello, I've been asked to design a primary reformer for the extraction of hydrogen from methane for haber bosch process - final year project. I have the flow rate, temperature and pressure. I just want to know how I would use this information to design the reformer? How exactly do I use the steam ratio? Do I use the same calculations as the packed bed reactor to work out the number of tubes required? Thanks. -Mo

[thorium90]

I assume you want to design a steam methane reformer? So what kind of furnace are you using? Side fired, top fired, convection type? The calculations would be similar to packed bed reactor but with heat flux at the tube walls. The number of tubes would depend on the plant production. More products mean more tubes needed. The appropriate steam carbon ratio to use would depend on the type of feed used and would determine the product composition. Low ratios cause coke formation and carbon laydown.

Edited by thorium90, 22 February 2013 - 10:14 AM.

[rifat]

thank you thorium90 - your assumption is correct. According to my research, the most commonly used is top fired, so I will be using that. Is there any material that you could possibly reccommend to further my research. thanks once again.

[thorium90]

Steam methane reforming is very widely used and there are lots of literature out there on it. Should be very easy to find. Xu and Froment's kinetics are widely used for modeling. Nielsen has many articles on the technology too. How do you intend to do the modelling? Software? Rigorous or more simplified modeling? You might find side fired is easier to model than top fired.

Edited by thorium90, 22 February 2013 - 12:07 PM.

[rifat]

Thank you, I will have a look. We don't actually need to model it per se just work ou the basic calculations i.e. reactor size, number of tubes, type of catalyst etc. Would you still reccommend to go for side fired?

Edited by rifat, 22 February 2013 - 12:17 PM.

[thorium90]

Well, if you dont have to do any modelling, it would become alot simpler. Decide on a rate of heat flux, the production volume, airflow, fuel etc, a simple heat and mass balance will complete your project's calculation in under 1 day.

Edited by thorium90, 22 February 2013 - 12:30 PM.

[rifat]

Thank you very much for your time. I'll come back if I need further guidance.

[miraa]

hai i need the formula to design the mechanical design for primary reformer in ammonia and urea plant which consist of furnace design. could u guys help me what the calculation or the step to complete the design? myb some reference that i can refer?