Feasibility study for recovering waste heat in the steelmaking industry using a chemical recuperator

This paper studies the possibility of developing a new heat recovery system from various hot wastes generated by the steelmaking industry, by utilizing the endothermic heat of reaction instead of sensible heat. In the proposed system, the waste heat of the gas was first stored using a Phase Change Material (PCM), and then supplied to an endothermic, methane-steam reforming reaction (MSB) as a heat source. The molten slag was granulated using a rotary cup atomizer (RCA) and the sensible heat of the slag was recovered using MSR. A heat and material balance model was developed to evaluate this system and to predict all its operating data. An exergy analysis and an economic evaluation were conducted on the basis of the predicted data. The results showed that the exergy loss in the proposed system was only 15% from the total exergy losses in the conventional system, and that the annual cost benefit of the proposed system totaled US$ 409 million from heat recovery, and US$ 1 945 million from slag granulation.