Eco-Stock solutions for the valorization of complex industrial waste heat – SOLUTEC

Nowadays, the industry looses more than 20% of the energy it consumes in flue gases under the form of so-called waste heat. More than 3500 TWh are lost every year in the world, emitting unnecessarily 2500 Mt CO2eq and a shortfall of around 200 billion €. Waste heat rejected by industry in France reaches around 109.5 TWh (or 36% of its energy consumption) of which 52.9 TWh (16 Mt of CO2, or 2 billion €) are lost above 100°C by several industrial sectors. This leads to different waste heat sources which have various properties in terms of temperature, composition, pollutants concentration, dynamics, etc. In order to valorize all these waste heat sources, it is necessary to develop an efficient thermal storage solution adapted to all temperature ranges and types of waste heat, with a contained cost, stable performances and low environmental impact.
Eco-Tech Ceram (ETC) is a young innovative company commercializing the Eco-Stock®, a thermocline sensible heat storage that valorizes the industrial waste heat from furnace fumes. The fumes are blown into a tank filled with ceramic materials to which they transfer their heat. The heat recovered can be later restored for utilization by blowing ambient air into the tank. This technology provides carbon-free heat with a cost from 7 €/MWh, which is around 80% cheaper than by using natural gas in France. However, the Eco-Stock® solution is currently limited to the valorization of “clean fumes”, which do not involve corrosion nor fouling of the system, and which represent only 20% of the total waste heat potential. The LabCom SOLUTEC (Eco-Stock solutions for the valorization of complex industrial waste heat) will tackle the valorization of complex fumes by developing suitable scientific and technical expertise adapted to these “unclean” waste heat sources.
The LabCom SOLUTEC relies on profuse and close collaborations established since 2015 between the laboratory RAPSODEE* and ETC. Previous and current works have revealed the complexity of physico-chemical, thermal and thermo-mechanical phenomena which take place inside the studied energetic systems, notably those due to corrosion and condensation. Those first results, together with the LabCom partners’ R&D strategy, allows the definition of the LabCom SOLUTEC. Its long-term vision (2021-2030) aims at providing efficient thermal storage solutions for the valorization of waste heat from complex fumes. The 2021-2025 period will focus on the two main industry sectors targeted by ETC: ceramics and metallurgy. Work will be devoted to the characterization of fumes, the identification and comprehension of corrosion and condensation mechanisms involved inside the storage tank, and the control of these phenomena under real operating conditions. New efficient solutions will be developed at large industrial scale (TRL 6 to 8) to produce new Eco-Stock systems (version 2 and following) suitable for the targeted sectors. The 2025-2030 period will be dedicated to the development of solutions for other industrial sectors which are already identified: cement plant, lime plant, steelworks, aluminum plant, glassworks.
Substantial human, financial and material resources will be raised for this LabCom SOLUTEC. The ANR support (29.8% of the total budget) is crucial during the first period to build the public-private partnership into a unique and stable structure dedicated to the energy transition acceleration supporting an innovative carbon-free industry.

(* : RAPSODEE - Recherche d'Albi en génie des Procédés des Solides Divisés, de l'Énergie et de l'Environnement – one of the 3 research center of IMT Mines Albi)