Technology Of Optimization And Energy Saving Of Heat Exchanger Networks

Heat exchanger networks are very common in petrochemical industry. They put hot streams which need to be cooled and cool streams which need to be heated together to use hot streams heat cool streams. Thus a lot of energy can be recycled and much utility can be saved. Energy saving can be fulfilled. Usually a better heat exchanger networks must make each stream temperature from initial to target under several conditions with minimum investing cost and minimum operating cost. Designing heat exchanger networks is an optimization problem. It is also a very important aspect in energy saving of petrochemical producing. On one hand, intelligent design approach is need in designing more and more. On the other hand, more practical knowledge must be used. This paper modified particle swarm optimization algorithm and used it to design heat exchanger networks with some practical knowledge in order to get a quick design rate, get better heat exchanger networks and make more benefit to factories.In this paper, different super structures were used to describe heat exchanger networks without split and with splits. A novel design approach based on particle swarm optimization algorithm was developed. The design objective is minimizing total cost. And minimizing investing cost and minimizing operating cost were designed at the same time.In designing heat exchange networks without split, it used individuals in population to describe heat transfer quantity of each exchanger. Besides getting some practical knowledge, it calculated heat transfer quantity of each exchanger on special order using particle swarm optimization.In designing heat exchange networks with splits, it used individuals to describe splits of each stream. It used two-layer optimization approach: firstly optimizing split number of each stream based on genetic algorithm, and then optimizing split duty based on particle swarm optimization.As heat transfer quantity in each exchanger is restricted under several conditions and each quantity affects each other, this approach used swarm intelligence to solve these problems and make designing process intelligent base on avoiding sophisticate calculation and keeping feasible of each individual during designing. The simulation result proves it effective. Then it is put into designing heat exchanger network in atmospheric and vacuum distillation to solve the actual simulation problem.All this work proves that intelligent technology such as particle swarm optimization is feasible in designing heat exchanger networks and has better result. It can be study more to design better heat exchanger networks and to get improved effect of energy saving.