CASE Study of an Organic Rankine Cycle (ORC) for Waste Heat Recovery from Cogeneration Systems

orc2019 Tracking Number 148

Waste heat is one of the important energy losses which has attracted attention to be captured and utilized or to be converted into electricity. As for the conversion concept, ORC is a developing technology [1]. The waste heat is available from different industrial sources such as flue-gas exhausts, offshore oil and gas processing platforms, kilns in the cement and steel industries and also combined heat and power plants (CHP). Several studies showed the potential of combined heat and power technology in energy intensive sectors. As an example, Alipour [2] concludes that the profitability of these CHP plants can be improved by selling excess heat to nearby customers. In this study the feasibility of an ORC driven by waste heat from a CHP plant has been investigated thermodynamically. A bio based gas turbine in Flanders was selected as a case study and its waste heat properties were considered as input to a model of an ORC plant. The exhaust gas temperature at full load is 427 (°C) in which the recoverable temperature for ORC can, roughly, be 180 (°C). Setting return temperature and the related evaporation pressure, the maximum cycle efficiency was obtained around 17% with a potential power generation of 180.6 kWe. Although this efficiency depends on several parameters such as the location and seasonal/ambient temperatures, the first step of the study showed acceptable outcomes. Currently the impact of various cooling technologies on the ORC performance is being investigated .