The Process Research On Hot Stuffy With Pressure And Sensible Heat Recovery Of The Molten Slag

With the development of iron and steel iudustry, the steel slag production is increasing year by year. The slag which is a kind of valuable secondary resource has considerable utilization value. However, due to the level of the slag processing technology and slag comprehensive utilization restrictions, comprehensive utilization rate of domestic steel slag is about20%, and the slag heat recovery is still at the stage of laboratory research. In order to improve the slag disposal level and promote the use of slag, China jingye Engineering Co., Ltd has developed the technology of slag hot stuffy with pressure which not only improve the treatment process level of slag, but also provided the conditions for the heat recovery of slag.In this article, we use the pilot production line of slag hot stuffy with pressure as the test platform to do the two test studies. On the one hand, according to experiment of slag hot stuffy with pressure to carry out structure optimization of equipment package, and to determine the main parameters of the process of slag hot stuffy with pressure. On the other hand, Making air-cooled roll crushing process replace water-cooled roll crushing stage, and on this basis do exploratory experiments of heat recovery of slag. The test results are as follows:Through the hot stuffy with pressure test of slag, we perfect test line which include water supply system, exhaust system and device sealing system, match the speed of the roller press and transit trolley reasonable, and identified some process parameters of the test line. The main parameters:In water-cooled roll crushing stage, slag is treated with intermittent fetch water and roll rusher, per tom of steel slag need water0.375m3, processing time is30min, the temperature at which slag is put into tank is700～800℃, the slag put into tank whose particle size greater than300mm is less than20%. In hot stuffy process, per ton slag need water0.3m3, hot stuffy pressure is0.4～0.7MPa, and hot stuffy time is1.5h.The chalking rate of slag processed is70%, and the soaking expansion of slag is less than2%, whose moisture content less than5%, the slag and iron are well separated,and the activity index of slag meet the relevant technical requirements of high value-added use of slag. Exploratory pilot study about heat recovery of slag verify technical feasibility that use air forced cooling slag for heat recovery of slag. Studies have shown that the factors including blast way, blast volume, exhaust volume, the roller speed and travel speed of roller press, air cooling time will have a certain impact on slag temperature, air temperature and heat recovery, under optimal conditions, recovering heat of slag will get180℃hot air, and heat recovery rate achieve38.2%.Research on hot stuffy and heat recovery process of slag provide a theoretical basis for technology promotion of hot stuffy with pressure of slag, and laid the foundation for the successful development of the heat recovery technology of slag.