ZIM project ZF4042202RE6

Development of a recuperator for the hybrid combustion air pre-heating in industrial furnaces

The majority of industrial furnaces in the metal, ceramic and chemical industries use fossil fuels, especially gas, oil and coal. For energy-efficient operation, the furnaces are equipped with a heat recovery system for preheating the combustion air. Central recuperators are often used for this purpose. An essential requirement for plant operators is the use of electricity from renewable energy sources such as wind or solar energy. Due to the increasing feeding of wind and solar energy into the power grid, the output generated is subject to considerable fluctuations. In combination with the liberalisation of the energy market this leads to an increasing volatility of the electricity price.

The aim of the research and development project is to improve the energy efficiency and cost-effectiveness of gas-fired industrial furnaces with combustion air preheating via central recuperators. For this purpose, the development of a new hybrid recuperator with integrated, electrical combustion air preheating and adaptive control of the air volume flows will be pursued.

This innovative product will be realised by using central tube bundle recuperators with integrated electrical heating elements, which enable hybrid combustion air preheating both through the heat of the exhaust gas and with electrical energy, thus ensuring flexible power supply, especially from excess electricity, from renewable energy sources. Nevertheless, the system is fully functional in de-energised operation. This also makes it possible to retrofit existing, exclusively gas-fired plants for the proportional use of electricity from renewable energy sources and to contribute to the stability of the electricity grid and the success of the energy system transformation. The joint research project comprises the experimental and numerical design, construction and manufacture of a prototype of the hybrid recuperator.


The research project with the funding code ZF4042202RE6 is funded by the Federal Ministry of Economics and Energy on the basis of a resolution of the German Bundestag.