Simulation and optimization of waste heat recovery in sinter cooling process

The particle size, the gaseous velocity and temperature at the inlet, and the porosity and the height of the sintered bed are the five main parameters affecting the efficiency of the waste heat recovery in a sinter cooling process. A numerical model was developed on the basis of the porous media model and local non-equilibrium thermodynamics model, to reveal the flow and heat transfer characteristics of a 420 m2 sinter cooler in an iron and steel company with the software package Fluent 6.3. Simulation was carried out and influences of different parameters on the distribution of solid temperature, the gaseous temperature and velocity, and the waste heat utilization were discussed. The reliability of this model was verified by comparing the prediction data with the experimental data.In order to investigate the influence of multi-layer feeding on waste heat utilization, 10 parameters including the above five were optimized with the mixed orthogonal experimental method. The significance degree of the parameters was obtained. The optimal combination of the parameters was proposed in the purpose of improving the waste heat utilization. The amount of waste heat utilization is 2.5531 × 108 kJ/h in the optimal condition, which increases 26.26% compared to the standard condition.

► We establish a mathematical model of flow and heat transfer in sinter cooling process.
► We research the influence of parameters on waste heat utilization.
► We examine significance degree of the parameters in affect waste heat utilization.
► We develop the combination of optimal parameters in purpose of increasing waste heat utilization.