Constructal optimization of a sinter cooling process based on exergy output maximization

Based on constructal theory, sinter cooling process optimization is performed in this paper. Exergy output of recovery waste heat is maximized, and the optimal cross-sectional shape of the sinter layer is obtained. The result shows that the exergy output of the recovery waste heat with optimal height of the sinter layer is increased by 22.80% compared with that with the height equal to a common value of 1.40 m. The exergy performance of the recovery waste heat is evidently improved after constructal optimization, and it can be further improved by adopting a lower porosity and a higher initial temperature of the sinter layer, a smaller equivalent diameter of the sinter particle as well as a larger velocity of the inlet air. Moreover, an upright trapezoidal cross-sectional area of the sinter layer leads to an improvement of the exergy performance, but the conclusion is reversed for an inverted trapezoidal one. The results obtained herein can provide some new guidelines for the optimal designs of the sinter cooling processes.