关键词: 水网络, 优化, 热集成, 全过程系统

Abstract:

In a practical water using process, a temperature requirement exists. Thus, it is significant to consider the temperature constraint in water network integration to decrease the water and energy consumption at the same time. Besides, there are non-water process streams which only have temperature requirements in the process system. If these streams are integrated with water streams in the water network, better energy efficiency can be reached. In this paper, a method for optimizing water networks is proposed under the background of heat integration in whole process system. First, an LP model is established to obtain the initial status of the water network and stream data. Then, four rules for non-isothermal mixing are proposed by comparing the relative position of water streams with the background and whole process pinches to exclude the irrational non- isothermal mixing. Finally, the heat integration in the whole system is performed with minimal total annual cost as the objective function. A case study is used to show the feasibility of the method, which can get a decrease of 6.27% in the annual cost.

Key words: water network, optimization, heat integration, whole process system