J. Jirat et al., Comparison of design and operation strategies for temperature control during selective catalytic reduction of NOx, CHEM ENG TE, 24(1), 2001, pp. 35-40
The problem of controlling temperature profile along a monolithic reactor i
n which an exothermic reaction (selective catalytic reduction of NOx by hyd
rocarbons) takes place is considered. Several solutions are proposed and co
mpared. It is shown that a near optimum temperature profile can be achieved
by two rather different approaches - one based on periodic switching of a
hot reactant and a cold inert stream between two thermally coupled monolith
s, and one based on pre mixing the reactant and coolant streams. An adaptiv
e control scheme based on model-predictive control is proposed and shown to
be efficient for the case of time-variable properties of the reactant stre
am.