Generation of Energy Conservation Measures for Sponge Iron Plants

During the operation, a tremendous amount of heat is generated in the coal based sponge iron plant and a significant part of this heat associated with the waste gas, remains unutilized. While utilizing this heat in the process the energy demand of the process may be reduced, which decreases the coal consumption, which is the only source of energy for this plant. To utilize the heat associated with waste gas pinch analysis is applied on the actual plant data to identify three feasible cases for energy conservation. For these cases capital investment required for retrofitting as well as total profit in terms of coal and water saving are compared and best design is selected. The best design includes preheating of air using waste gas. It consumes 5.4% less coal in comparison to existing system. The payback period of the best design is 48 days only. This design also satisfies the practical conditions of the process.