Thermodynamic Assessment Of Energy Efficiency And Exergy Losses In Industrial Heat Recovery Processes

Abstract

Industrial processes reject a substantial fraction of primary energy input as waste heat through flue gases, cooling 
streams, and process effluents, representing both an environmental burden and an untapped economic resource. 
This review synthesizes past research on thermal performance optimization of waste heat recovery (WHR) systems 
across low, medium, and high temperature industrial applications, spanning cement, steel, glass, chemical, and 
food-processing sectors [1]. Technologies surveyed include organic Rankine cycles, Kalina cycles, thermoelectric 
generators, heat pumps, Stirling engines, heat exchanger network retrofits, and hybrid recovery architectures. A 
meta-analytic synthesis of reported efficiency values, exergy destruction patterns, and payback periods from the 
literature is presented, alongside methodological approaches used in prior optimization studies, including 
thermodynamic modelling, exergo-economic analysis, machine-learning-assisted design, and multi-objective 
optimization. The critical analysis identifies recurring gaps: inconsistent baseline assumptions, limited techno
economic transparency, underexplored transient and part-load behaviour, and scarce field validation of 
laboratory-scale results. The discussion consolidates these findings into design and policy implications for 
improving adoption rates of WHR technologies. The review concludes that combining thermodynamic rigor with 
data-driven optimization and standardized reporting protocols offers the most promising route toward closing the 
gap between theoretical recovery potential and realized industrial energy savings, and outlines directions for 
future investigation including dynamic operation, materials durability, and integration with renewable and 
digital-twin frameworks [2].