Waste Heat Recovery in Automotive Paint Shop via Organic Rankine Cycle and Thermal Energy Storage System—Selected Thermodynamic Issues

Abstract

Baking ovens are necessary to be installed in a paint shop of assembly automotive manufacturers for drying the paint of automotive bodies (i.e., in the coating process). In this process, a large amount of heat is provided by burning the natural gas in the gas burner. Practically, the design of the heat confinement in the oven is often poor, which results in considerable heat losses (i.e., waste heat) which are released during the drying process and significantly raise the temperature of a working environment thereby lowering the thermal comfort of the factory staff. To address this issue and limit the waste heat transfer to the surroundings, the application of a waste heat recovery system of a specific design employing the organic Rankine cycle (ORC) may be a viable alternative solution. A combined design of such a system utilizing an evaporator and thermal energy storage (TES) device in a simple ORC layout will be discussed in this article. The obtained simulation result was computed using MATLAB coupled with thermophysical properties libraries, i.e., CoolProp. The obtained results indicate that the sustainability of the studied system scheme appears to be favorably implemented in the selected paint shop and may benefit to lower the temperature of the working area, improve the thermal comfort of factory staff and at the same time produce electricity since some car/automotive manufacturers likely run the production for over 20 hours per day.