An integrated optimization model and application of MEE-TVCCTEDLu Shuai, Yihui Zhou ⁎, Mingshu Bi, Jingjie Ren, Zhen CaiSchool of Chemical Machinery, Dalian University of Technolog

Multi-effects evaporation with thermal vapor compression (MEE-TVC) is one of the most effective desalination method in which the TVC plays a main role with consideration of energy consumption. In this paper, the steady- state mathematical model of MEE-TVC based on LINGO algor ithm is developed and is examined against commercial desalination plants. The model can be adapted to convent ional equal temperature difference design method and equal heat transfer area design method as well because of the generality of the model and the maintainability of the programs. By inducing suction position variable the in fl uence of parameters of TVC including suction position, suction pressure, motive vapor pressure, top brine temper ature etc. on the operation of MEE-TVC system is investi- gated. It is found that the improvement of performance ra tio and decreasing energy consumption can be achieved by optimization of integrating TVC suction position with operations of each effect. The end effect is almost the optimal position for TVC expect for some cases in equal temperature difference design situation with regards of the gain out- put ratio

GR F hd hfd hgr hs L Mc NEA Ps Pr Pd Qd Ss Sfd RE TR A A general optimization model of MEE-TVC has been developed in the paper. By introducing the suction position variable the coupling interaction between TVC and MEE has been considered fully and finally the optimal performance parameters of MEE, TVC and the optimal suction location have been obtained by programming with Lingo®. The program can apply not only to the equal temperature difference design but also equal heat transfer area design. As far as the equal temperature difference design method is concerned, the optimal suction position is usually at the end effect. However, the position has a trend of moving forward when the MEE-TVC system has more than 10 effects. While for the equal heat transfer area design method, the optimization results illustrate that the best suction position is always at the last effect. By comparison of optimization design procedures of two different methods, the latter one is the more usual way in the industry due to easier manufacture although the output gain ratio is less than that of the former one.