Comprehensive Evaluation And Analysis Of Organic Rankine Cycle Based On AHP-entropy Value Method

With the rapid development of the social economy, the human demand for energycontinues increasing, while the traditional fossil energy such as coal, oil and otherreserves is limited, and not only have been unable to meet the demand of rapid andcontinuous development of human society, but also the environment of human survivalhas been serious damage when the fossil energy in the process of exploitation andutilization;Therefore, all countries in the world are doing their best to develop newgreen energy and environmental protection ways to use energy.Organic RankineCycle(ORC) using the characteristics of low boiling point organic working medium torecycle low grade thermal energy is a effective measures to reduce fossil energyconsumption and the pollution to the environment, furthermore this technology hasbecome the focus of the higher scientific research institutes around the world.The optimization analysis of the ORC system has become a focus research of theORC,however the comprehensive evaluation and analysis of the ORC system canreflect its overall performance clearly.So firstly in this paper, the subcriticalpureworkingfluid ORC system is studied,and the general law of thermodynamic performance of theORC systemis received,and on this basis to study the relationship between theevaporation temperature and the thermodynamic performance of theORCsystem underthe influence of the pinch point temperature different;Secondly, the economy and theimpact on the environment of the ORC systems is analyzed and calculated; Bycalculating, the economic evaluation index of the ORC system is obtained: HeatExchanger Area Per Unit Power Output(APR) and Levelized Energy Cost(LEC); Whenstudy the impact on the environment of the ORC system, the contribution of the leakageworking fluid of the ORC systems to the Global Warming Potential(GWP) and OzoneDepletion Potential(ODP) is taking into account, and has also carried on the quantitativeprocessing, besides, the contribution of the ORC system to the energy conservation andemissions reduction has been analyzed and calculated. At last, using the AnalyticHierarchy Process(AHP) to establish the comprehensive evaluation model of the ORCsystem, and through the Entropy Value method to determine the evaluation indexweighting factor in every class time, and then get the comprehensive evaluation indexξofthe ORC system, by considering its thermodynamic performance and economicalefficiency and the environmental impact. Through analyzing and comparing the comprehensive evaluation index ξ of the ORC system, the most suitable organicworking fluid and the best evaporation temperature is obtained.In this paper, By researching the thermodynamics performance, economicalefficiency and the impact on the environment of the ORC system, the thermodynamicevaluation index and economy evaluation index and environmental impact evaluationindex are obtained, and then the comprehensive evaluation index ξ of the ORC systemis obtained by AHP—entropy value method, finally realized the purpose ofcomprehensive evaluation of the ORC system.