Exergy Analysis And Numerical Simulation On Sinter Cooler Waste Heat Recovery System

In the steel industry, the energy consumption of sinter cooler lies in the second just behindpudding, which accounts for25-30%of total energy consumption. High efficient recovering andreasonable utilizing the sintering waste heat has extremely significant meaning for steelenterprises to implement energy conservation, emissions reduction and environmental protection.Due to the sintering system in vulgar development for a long time, the domestic has fewtheoretical data to support.So it is necessary to do deep research of the thermodynamic progressof the sinter cooler and master the methods of improving the efficiency of sintering waste heat.In this dissertation, a520m2sinter cooler waste heat recovery loop system was studied asthe research object in Handan iron and steel. It was introduced that basic components of theannular cooler contained the waste heat boiler, waste heat recovery system, etc. Meanwhile, inalso contained the exergy analysis of thermodynamic cycle with or without inner loop heatrecovery systems. The results showed that the circulatory system exergy efficiency was4.37%,higher than without the circulatory system exergy efficiency.Also in this paper, computational fluid dynamics software FLUENT14.5was used to modela mathematical cooling process of the sinter cooler. ANSYS ICEM CFD was used to dividestructured grid of the computational zone, And standard k model was used to describe the airflow in the sinter cooler, employed with the local thermal non-equilibrium heat transfer model ofporous media, a numerical simulation of the cooling process of the sinters was made. Thevariation of temperature, velocity, pressure distribution along with time were obtained. And thenthe paper analyzed the effect of different control parameters and thermal parameters on the sintercooler cooling process and the waste heat recovery. And all the simulation results was conductedby CFD-Post, Tecplot360, Origin and other post-processing software output. Simulation resultsshow that:(1) The air velocity of the sinter cooler was influenced by temperature and structure size oftrolley. The static pressure decreased significantly after the cooling air flowing through theporous region. And the higher the temperature was, the greater the static pressure dropped. At theporous region, along with the increase of height, the air and the sinter temperature increasedgradually, and when the air left the sinter, the temperature basically unchanged.(2) The comparison of the numerical simulation results and field measured data showed thatall errors are less than10%, which proves the reliability of numerical simulation.(3) The paper focused on the influence of the material layer height, porosity, sintered ore particle size, initial temperature of the cooling air on the cooling process and efficiency of thewaste heat recovery. The results showed that in the range of1000~1500mm, increasing theheight of the material layer, in the range of0.35~0.50, reducing porosity, in the range of0.03~0.06m, reducing the particle size of the sintered ore and in the range of393~423K,improving the initial temperature of the cooling air all could increase the outlet air temperatureof waste heat utilization area and exergy efficiency of the sinter cooler. And after the comparisonbetween calculation results and test results, the four optimized parameters value was obtained.