Optimization Of Multi Effect Evaporation System In Sugar Refinery

Vaporization of water of multi effect evaporation process in sugar refinery need to absorb a lot of heat, so the multi effect evaporation process is the most energy consuming section in sugar production process. The multi effect evaporation system designed by conventional design method is more or less imperfect. For example, the calculation of the heat transfer area of the whole multi effect evaporation system, the conventional design method is mostly based on the method of empirical estimation, or given an initial value by estimating, and then review. The method is rough, it is neither conducive to save the cost of manufacturing equipment nor to the distribution of energy consumption of evaporation operation, if the optimum design method is adapted, the optimum design parameters can be obtained in the condition of meeting the production process.The paper established a mathematical model of multi effect evaporation system of sugar refinery.it takes the total heat transfer area as the objective function, it takes the effective temperature difference as the decision variable, it is the constraint condition that the sum of effective temperature difference is equal to the total heat transfer effective temperature difference, it is the constraint condition that the effective temperature difference of every evaporation tank is more than 5. The mathematical model with the characteristics of the multi variable, highly nonlinear, inequality constraints and equality constraints, so, it is very difficult to solve. In this paper,the breeding algorithm is firstly used to solve practical engineering optimization problems. In order to form a comparison to prove the correctness of the results of the breeding algorithm, genetic algorithm is used to solve the mathematical model at the same time. This paper present two case study of four effect evaporation systems and five effect evaporation systems, the optimized design results are compared with the conventional design.The results show that the multi effect evaporation system mathematical model is correct, can better simulate the actual situation, and has strong universality. In the case of the same heat transfer coefficient of the original program. The total heat transfer area of the genetic algorithm and breeding algorithm is 10.61% less than that of the original scheme, in the case of the four effect evaporation system. In the case of five effect evaporation system, the total heat transfer area calculated by the algorithm is 7.186% less than that of the original scheme, the total heat transfer area calculated by the breeding algorithm is 7.452% less than that of the original scheme. The calculation results of breeding algorithm are basically the same as the results of genetic algorithm, that illustrate the effectiveness and stability of the breeding algorithm.