Abstract: As “green solvents”, ionic liquids have attracted much attention in the area of electrochemistry, organic chemistry and biochemistry. Recent studies focus on the synthesis and application of ionic liquids.However, the studies on degradation of ionic liquids which concerned with environment are not enough. The degradation of ionic liquids is required before the large-scale use of ionic liquids. In this study, chemical degradation method and biodegradation method are summarized. The chemical degradation is mainly achieved by UV/H₂O₂, Fe (Ⅲ)/H₂O₂ and electrolysis system. Biological degradation is achieved by introducing functional groups with enzymatic site, or using monooxygenase to oxidize the methyl terminal of alkyl side chain on the cation of ionic liquids into hydroxyl and aldehyde to form carboxylic groups, and then β-oxidation is proceed. Different chemical structures of ionic liquids is designed according to different mechanism between chemical and biological degradation, for example, changing the length of alkyl chain or introducing the functional groups that are easily degradable and selection of microorganism could improve efficiency of degradation of ionic liquids.

Key words: organic Rankine cycle, efficiency, linear weighted technique, comprehensive evaluation index, internal heat exchanger

摘要： 将换热器置于有机朗肯循环(organic Rankine cycle,ORC)系统,并结合不同工质对ORC性能进行研究。论文基于热效率、 效率、经济性能指标和热回收效率建立目标函数,通过线性加权法提出了一种新的综合评价指标,以此对加入内部换热器(IHE)的不同工质的ORC系统进行评价和分析,尤其是着重对工质为R123系统进行了分析。由于加入内部换热器后,经过膨胀机的较高温气体与经过循环泵的较低温气体换热,可知该系统可以降低预热工质所需能量的损耗,并通过分析改变蒸发冷凝温度使整个系统的综合性能得到了提高。

关键词: 有机朗肯循环, 效率, 线性加权法, 综合评价指标, 内部换热器