COMPARISON OF DIFFERENT MINLP METHODS APPLIED ON CERTAIN CHEMICAL-ENGINEERING PROBLEMS

In this paper a comparison of some of the methods available for solvin g mixed integer non-linear programming (MINLP) problems is presented. Since some methods solve both a mixed integer linear programming (MILP ) master problem and non-linear programming (NLP) subproblems during t he iterations, while others only solve MILP master problems, a compari son of the computer resources needed for the optimization is presented . The methods are applied on a number of significant chemical engineer ing problems involving both MINLP problems (with a variety in the degr ee of discreteness and complexity) and some strict integer non-linear programming (INLP) problems. From the results, it is to be seen that a comparison of only the number of iterations needed in the optimizatio n, doesn't allways measure the actual required resources of the optimi zation.