1985 Volume 21 Issue 7 Pages 747-753
The present paper deals with an optimal planning for operating an oxygen plant. The plant consists of air turbo compressors and separators, and produces several kinds of gases used in a steel making process. For reducing energy loss and operating cost, we need to operate each equipment in the plant with due regard to optimizing the combination of the equipments. This idea is important especially under the situation where some redundant equipments exist according to lowering of demand.
The problem is formulated mathematically as a mixed-integer linear program with an angular structure. Then the decomposition algorithm proposed previously is applied to the problem in order to obtain a good suboptimal solution quickly. The procedure is to solve a restricted master program and subproblems iteratively. The master program is a linear program and the subproblems are mixed-integer programs with a single binary variable. Therefore, we need only a subroutine of the revised simplex method for solving these problems. Furthermore, the algorithm is revised by introducing a heuristic idea to adapt to the present problem.
Comparisons are made among several algorithms for the numerical examples which are given by assigning real demand conditions. It is observed from the results that the proposed decomposition algorithm is more efficient than the one being currently used from the viewpoints of the computation time and the accuracy.
