| China's annual output of iron and steel ranks the top in the world,and a large number of solid wastes produced by iron and steel enterprises,such as blast furnace dust and mud,gas mud and OG mud,seriously pollute the environment and are difficult to deal with.The process technology of reducing iron in rotary bottom furnace can turn these wastes into treasure and reduce them into smelting raw material-reducing iron by calcining.Cooling is one of the important processes in the process of forming reducing iron in rotary bottom furnace.The temperature of reducing iron pellets at the outlet of rotary bottom furnace reaches 1100?,which requires rapid cooling to below 300?.There are many kinds of reducing iron coolers used at home and abroad.In this paper,by means of CFD numerical simulation software,numerical simulation analysis was carried out on the spray cooling process set up single nozzle,the nozzle array,rib wall spray cooling mathematical model and calculation model,and the specific study on the different physical parameters and the structure form,the results in order to further improve the cooling efficiency of the spray cooling drum machine,optimize the structure of equipment,and provide theoretical support for engineering applications.The main work and achievements of this paper are as follows:1.In the full analysis of the basic characteristics of the tube wall spray cooling in vitro,theoretical model and numerical calculation method on the basis of the spray cooling,established a calculation model for the reduced iron cooling machine single nozzle spray cooling,cooling water temperature and wall temperature are researched,the influence of the height and direction of the spray nozzle,and the number array different spray nozzle are simulated,and study the influence of the number of nozzle on the spray cooling efficiency.2.In order to further improve the cooling efficiency of the cooler,a finned cooling cylinder was proposed,and the finned structure and arrangement were studied.Two types of axial straight rib and circumferential ring rib were designed and the density distribution of circumferential ring rib was compared and analyzed.The influence of different rib positions on spray cooling during cylinder rotation was analyzed.The simulation results verify the superiority of ribbed cylinder compared with unribbed cylinder.3.In view of the problems and deficiencies in the operation of the existing reducing iron spray rotary drum cooler,the key structure was optimized,and the cooling modes of swimming integral heat-resistant liner,integrated wheel belt and ribbed wall surface were designed.Compared with the traditional welded heat-resistant liner,the floating integral heat-resistant liner not only has higher reliability,but also can significantly improve the service life of the barrel at the feeding end.The integrated wheel belt has simple structure,convenient installation and maintenance,and reliable operation.The rib wall cooling method can improve the cooling efficiency,reduce the volume of equipment and improve the reliability.4.According to the technological requirements of the production line of an enterprise,complete the customized development and design of the cooling machine,and put forward the control requirements.The cooling machine design and development,quality inspection,installation and debugging as well as the whole process of equipment operation tracking services are realized. |
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