OPTIMAL-DESIGN OF AN AMMONIA-SYNTHESIS REACTOR USING GENETIC ALGORITHMS

This paper presents an optimal design procedure of an ammonia synthesi s reactor using genetic algorithms (GAs)-search and optimization techn iques based on principles of natural genetics. GAs are chosen as an op timization tool simply because of their successful application to many engineering optimization problems. The optimal problem requires maxim isation of an objective function subject to a number of equality const raints involving solution of coupled differential equations. Although there exist at least a couple of other studies on the optimal design o f ammonia synthesis reactor, they have ignored some terms in the formu lation of the objective function, for which the reported optimal solut ion does not match with the solution obtained using an enumerative sea rch technique. This paper includes those terms and applies GAs to find the optimal reactor length. Simulation results with GAs find optimal reactor lengths at various feed gas temperatures at the top of the rea ctor, The results of this paper are also found to agree with the react ors used in industries. The successful application of GAs in ammonia r eactor design suggests GAs immediate application to other reactor desi gns or modelling. Copyright (C) 1996 Elsevier Science Ltd