Page 301 - Introduction to chemical reaction engineering and kinetics

282 Chapter 11: Preliminary Considerations in Chemical Reaction Engineering

equilibrium data
thermodynamic
equation of state
thermochemical data
enthalpy of reaction
heat capacities
other physical property data
density
viscosity
cost data
The lack of appropriate information, particularly rate data over the entire range of
operating conditions, is often a major impediment to a complete rational design. If suf-
ficiently important, new experimental data may have to be developed for the situation
at hand.

11.1.1.4 Tools Available
The rational design of a chemical reactor is perhaps the most difficult equipment-design
task of a chemical engineer. All the tools in the workshop (or, to use a more belligerent
metaphor, all the weapons in the arsenal) of the chemical engineer may have to be
brought to bear on the problem. These include those relating to all of the following:

(1) rate processes and rate laws
reaction kinetics
development of a reaction model/kinetics scheme
diffusion and mass transfer
diffusion equation
mass transfer model (e.g., two-film model)
heat transfer
as part of thermal characteristics, including T profile
fluid mechanics
flow patterns
mixing
pressure drop
(2) conservation and balance equations
mass balances, including stoichiometry, continuity equation
energy balance, including energetics of reaction, thermochemistry
(3) equilibrium
reaction equilibrium, single or multiphase systems; equilibrium conversion for
comparison
phase equilibrium, multiphase systems
(4) mathematics
development of a reactor model from above considerations
analytical or numerical methods for solution of equations, simulation
statistical analysis of rate data
(5) computers and computer software
use of a PC, workstation, etc., coupled with software packages to solve sets of
algebraic and/or differential equations, and to perform statistical analyses
v
necessary for implementation of a reactor model for design or for assess-
“OF
ment of reactor performance
0 (6) process economics {
software: spreadsheet packages, simulation software, numerical equation
4
solvers, computer algebra system (e.g., E-Z Solve and Excel)
i