Simimulation And Optimization Of The Complex Water Salt System Production Process

Rich chemical resources are contained in seawater.Its development and utilization has always been concerning by the world.Though the technology of comprehensive utilization of seawater is relatively mature in China,it also exists a series of problems,such as high production costs,slow speed of development,small scale,supporting facilities imperfect and so on.Therefore,how to efficiently use the seawater chemical resources,reduce production cost and the adverse effects on the environment,is an urgent problem to be solved.The comprehensive utilization system of seawater have been overall optimized which the purpose is to reduce energy consumption in this paper.Finally the optimal process route and operation parameters were determined.Some related theories in this article were introduced,including the simulation and optimization of process systems,material balance and heat balance as well as Aspen Plus process simulation software.A hierarchical optimization model of comprehensive utilization of seawater system was established based on the hierarchical decomposition principle.Seeing that the complexity of the seawater system,the sylvite preparation of the potassium chloride process as an example was introduced.For the propose of reducing the process system energy consumption,from the point of view of the application of the Aspen Plus software,the optimization analysis method about comprehensive utilization of seawater system is introduced from two levels of unit operation and product production,which provides the theoretical guidance and technical support for the comprehensive utilization of seawater.The production process of potassium chloride was simulated and optimized with the help of Aspen Plus software.First of all,the solubility data which were calculated by the ELEC-NRTL,Pitzer-2,Pitzer-3 model respectively were obtained.Through analysis and comparison,the Pitzer-3 model was the best property method.The bubble point pressure at different temperatures,the optimum water addition of sylvite.the amount of raw materials and liquor circulation were obtained.In order to reduce the energy consumption,the sylvite preparation of the potassium chloride process was optimized.Different crystallization methods,flash series,string cold cooling water and liquor mixed cold were discussed respectively.Finally the optimal process route and operation parameters of sylvite were determined which provides reference for other inorganic salt production.