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.