Numerical Simulation Of Cooling Process And Testing Optimization Of Cooling Efficiency For Circular Cooler

Recently, with the coming of the word economic crisis, Chinese iron and steel industry is facing a severe challenge, which results in a poor market. Therefore, how to reduce the cost, consumption and pollution and save energe is becoming an important measure to achive sustainable development of the industry. In the process of iron and steel making, the recycling of waste heat from sintering is a great link to save energy and ruduce cost,so improving the cooling efficiency of circular cooler has practical significance to achieve this industry’s sustainable development.To study the heat transfer process of circular cooler and improve cooling efficiency, practical circular cooler is studyed in this paper. And combined field test with fluent simulation, the change of ore temperature, gas distribution and some other physical parameters in the process of cooling are measured. Then based on that, temperature and velocity field are simulated by fluent software. After comprehensive analysis, promoted measures are suggested and get simulation again. And distributing graph of gas velocity and changing graph of temperature are drawn on the condition of ideal state. The results are as follows:(1) Sinter ores in inner circle of trolly are mainly small particle averaging at 12.5~25mm. On the bottom of outer circle, small particle sinter ores account for a little proportion and big and small particle ores exist together on the top. And the average particle size of sinter ore from outer circle is 25~35mm.(2) In the process of cooling sinter ores from outer ores, cooling velocity of sinter ores at the same height 200~1200mm away from lateral wall of trolly is decreasing. The ores at 200 mm and 400 mm reach their cooling endpoint of 45~60℃ after 35.5min and the ores at 1200 mm almost reach its cooling endpoint after 50.5min.(3) Temperature variations of sinter ores from inner circle at the same height 200~1200mm away from lateral wall of trolly are basically similar. And because of fringe effect, the ores at 200~400mm reach their cooling endpoint of 100℃ and the ores at 1200 mm almost reach its cooling endpoint up to 400℃.(4) Air leakage rate of circular cooler tested in the plot is about 20.9% and the main air leakage sites are the gaps on trolly and between trolly and bellows. A large amount of cooling air leaks out from those sections, and some sealed rubber bearings are aging and broken, which should be replaced to reduce air leakage rate.(5) After experimental simulation, a conclusion is drawn that on the condition of even burden distribution, the height of layer at 1.3m and the average particle size at 25~30mm, the best cooling velocity of 43~45m/s is suitable.