Many high-temperature processes in the steel industry discharge waste heat directly into the atmosphere without recovery of the dissipated energy. Additionally, the industry has been compelled to reduce its fossil energy consumption through increasing reductions in carbon emission caps. Accordingly, the development of new technologies, or new uses of the existing ones, for the exploitation of waste heat is of considerable importance. This study analysed the feasibility of using heat pipe technology for a novel use; the generation of steam by taking advantage of the energy contained in combustion fumes from reheating furnaces. To the best of our knowledge, the present study is the first to explore the technical viability of this technology under laboratory conditions, reaching efficiencies between 39.7% and 62.7%. The laboratory results were extrapolated to the conditions of a real steel plant, and it was estimated that 65% of its steam needs could be covered using heat pipes, leading to substantial savings in steam purchase and carbon taxes that ensure the economic viability of this technology. The environmental viability was confirmed through a comparative life cycle analysis. Notable reductions in environmental impacts were achieved, including a 97% reduction in CO2 emissions.

European Union’s Horizon 2020 research and innovation programme under grant agreement No. 680599.

The majority of the energy demand in industrial application is primarily used for heating purposes. Recovering waste heat could contribute to significant reduction of production cost and greenhouse gas emission. In this paper, an innovative heat recovery system was designed, manufactured and tested. The Flat Heat Pipe (FHP) is designed to recover the heat by radiation from hot steel rods during the manufacturing cooling process. The FHP system is composed of stainless steel heat pipes linked by a collector at the bottom and a shell and tube top header. The thermal performance of the FHP was investigated by testing the system at two positions from the barrier of the wires conveyor. The amount of the energy recovered and the working temperature of the FHP is also reported. The experimental results show that the heat transfer capability of the FHP is strongly influenced by the hot source temperature. It was observed from the results that the FHP is an innovative technology for waste heat recovery from industrial applications with high efficiency.