Experimental Simulation of a Heat Recovery Heat Pump System in Food Industries

Many opportunities for heat pumping technologies exist for recovering the waste heat generated by industrial processes. By using heat pump systems in the right way, the use of primary energy and CO2 emissions as well as energy costs can be reduced. A laboratory flexible industrial scale heat recovery system is designed and built to carry out experimental simulations by reproducing the operating conditions of real case applications in food industries. The heat recovery system includes process integration technologies ranging from passive recovery like simple heat exchangers to technologies upgrading the waste heat like industrial heat pumps. The integrated heat pump is an electrically-driven vapor compression closed-cycle type, which can operate in a single-stage or in a 2stage configuration and has a variable speed screw compressor. Several typical scenarios of food industry processes for low-temperature heat recovery (heat sources between 30°C and 50°C) and heat upgrading are experimentally simulated showing the overall energy savings and the environmental benefits of introducing heat pumps in this kind of industrial applications. The optimal configuration of the heat recovery system is evaluated for each scenario.