Eco-Innovation - Ihobe

HEAT IT YOURSELF FOR SUSTAINABILITY. CIRCULARITY IN ENERGY-INTENSIVE INDUSTRIES

Generating new knowledge and innovation about the use and life cycle of materials and energy, identifying specific areas of action to increase material productivity, adopting innovative solutions and promoting resource savings and waste reduction are direct objectives of the transformative project on "Circularity in value chains" included in the 2030 Environmental Framework Programme for the Basque Country.

Most energy-intensive industries use energy in the form of heat and, once the process heat has been applied, the exhaust gases are discharged into the atmosphere via chimneys. The waste heat contained in these exhaust gases is the largest heat loss at manufacturing plants. Most industries using the Electric Arc Furnace lower the temperature and remove the contamination from the large amount of hot gases produced before releasing them into the atmosphere. Therefore, not only is the heat of the gases wasted, but also energy is consumed to treat them and lower their temperature before releasing them.

Waste heat recovery in industrial processes is a well-known topic, but only low/medium temperature solutions under "clean" conditions can be considered mature for widespread implementation. Hot streams containing harmful chemicals or condensible particles require more costly equipment and present fouling, degradation or contamination problems, and therefore require further research and implementation efforts to extract their full energy potential and to be cost-effective.

COLLABORATORS

CIC ENERGIGUNE leads the LIFE HI4S project, which has 8 participating entities (CIC ENERGIGUNE, ARCELORMITTAL SESTAO, ARCELOR MITTAL R&D, SDEA, ENERBASQUE, FIVEMASA, AZTERLAN and LCE). It aims to build a pilot plant to demonstrate a technology for combined heat and power production from the waste heat contained in the exhaust gases of an electric arc furnace (EAF). This innovative and cost-effective technology also seeks to increase the efficiency of the technology by incorporating an innovative thermal energy storage solution using steel mill slag as a thermal storage material.

LIFE HI4S will use high-temperature ceramic filtering systems to avoid the usual fouling problems of traditional technology, and thermal energy storage systems to convert the intermittent and inhomogeneous nature of the exhaust gases from the EAF into a continuous and homogeneous source of useful energy to be managed on demand. The recovered heat is preferably used for the preheating of scrap metal, with the remaining heat being used for the production of electricity through an ORC cycle, mainly for the self-supply of the pilot plant. Furthermore, LIFE HI4S will develop a digital twin of the heat and energy recovery plant, so that the best operating modes can be determined and scaling and replicability are facilitated.

The prototype for a heat recovery and electricity production plant that will enable waste heat from furnaces to be reused will be installed at the ARCELOR MITTAL plant in Sestao (Bizkaia), with the aim of measuring its environmental benefits "in situ" and demonstrating its economic viability.

IHOBE has contributed to the design of LIFE HI4S by requesting the development of a specific chapter on the BREF documents (European reference documents on best available techniques) on heat recovery from industrial processes, and the inclusion of a life cycle approach and business model.