Question

You find a publication from a research laboratory that identifies a new catalyst for ammonia synthesis. The article contains the following details about the process run in the author's lab:
The chemical reaction is N2 3H2 --> 2NH3
The reaction is exothermic
A fixed bed reactor is used with ruthenium catalyst on graphite support
The reactor is run at 430oC and 250 bar with space velocity of 8000 m3 m-3 h-1
At this temperature and pressure, the reactants and products are in the gas phase
The reactants are fed at flow rates of 400 lbmol/h H2 and 100 lbmol/h N2
The extent of reaction is 90 lbmol/h

You are considering replacing the current iron-oxide catalyst used in your ammonia synthesis plant with this newly discovered ruthenium-based catalyst. You plan to start your evaluation with a model in Aspen Plus and an economic analysis in APEA.

Based only on the information above from the literature, which project component would you select to map this reactor in APEA?

Answer 1

Answer:

Answer: RStoic

Explanation:

The reactor i will select to model this reactor in Aspenplus is RStoic

with the following reason;

Reason: Rstoic is used in Aspen software when the stoichiometry of reaction is known but kinetics isn't available. It can have one or more feed streams attached to it.

Reasons why other reactors are not preferred:

RYield: RYield performs the calculations based on the yield and we are not provided with the yield.

REquil: REquil is used when we are provided with stoichiometry of the reaction and information about equilibrium constant so that to perform chemical and phase equilibrium reactions & we are not provided with the equilibrium information.

RGibbs: Since reactor and products are in the gas phase, so it is not required to use it as it's used to minimise Gibbs free energy.

RCSTR: Reaction kinetics needed but we are not provided with it.

RPlug: Reaction kinetics needed but we are not provided with it.

RBatch: Reaction kinetics needed but we are not provided with it.