The continuous search for sustainable alternative energy to non renewable energy to mitigate
environmental pollution has made waste heat recovery from industries process, material and
energy streams frontier. Power plant technologies like steam and Organic Rankine cycle are
been research by researchers to improve waste heat recovery efficiency and energy
utilization. In this study Hexane and Toluene are the organic fluid used .Their performance in
waste heat recovery in the melting furnace of a Sulphuric Acid plant was compared with
conventional Steam Rankine cycle. Energetic and Exergetic analysis was carried out to
investigate the performance of Steam and Organic Rankine cycle for waste heat recovery
temperature less than 200oC. In the ORC ,Hexane and Toluene has over all system efficiency
90.7% and 82% respectively while SRC has 81% .The energy efficiency result was supported
by Exergetic efficiency where SRC has the lowest Exergy Efficiency of 74% while those of
Hexane and Toluene were 88%, 84% respectively. The energy efficiency revealed that ORC
has a better waste heat energy utilization performance at low temperature when compared
with SRC. Furthermore, Hexane has the highest power generation of 4.74 MW from low
grade heat source of 200oC.
It is therefore recommended that Hexane should be considered as a working fluid in
harnessing waste heat energy using Organic Rankine Cycle.
