High-Temperature Large-Scale Heat Pumps for Industrial Process Heat and District Heating Design and Integration of Two Industrial Case Studies
The decarbonization of industrial heat demand is a central challenge of the energy transition, as many energyintensive processes still rely on fossil fuels to supply high-temperature thermal energy. Electrification through high-temperature large heat pumps (HTHPs) enables the valorization of low-grade waste heat and its upgrade to temperature levels suitable for district heating and industrial processes. This paper presents the design, industrial integration, and operational concept of two large-scale applications. The first case study is a 6 MWth heat pump integrated in an Italian steel plant to recover continuous waste heat from the electric arc furnace cooling circuit and supply hot water to a district heating network up to 120 °C. The second case study is a 12 MWth heat pump coupled with mechanical vapor recompression (MVR) in a paper mill, producing superheated steam at 170 °C from wastewater-derived heat at approximately 18 °C; due to confidentiality constraints, only high-level process information is disclosed for this installation. The case studies illustrate that multi-megawatt HTHP systems can be integrated in complex industrial environments, complementing existing heat recovery solutions and enabling substantial reductions of fossil heat use and associated greenhouse gas emissions.