Study On Pellet Quality Optimization Of Hansteel

The pellet has good metallurgical properties.Compared with foreign blast furnace,the proportion of pellets on domestic blast furnace is relatively low.Combined with the production status of domestic blast furnace and the existing characteristics of iron powder,it can be seen that there is a great potential for the domestic blast furnace to improve the ratio of pellets.On the basis of the actual situation of raw material of Hansteel,the experiments of pelleting and roasting were made in the present paper using the disk pelletizing machine and other equipment.And the influence of technological factors and chemical composition on the quality of green pellet and metallurgical properties of pellets were investigated by adjusting the proportion of different iron concentrate powder to change the chemical composition of pellets.The main results are as follows:The research of the basic properties of Hansteel iron ore concentrate shows that the iron grade of five kinds of iron ore powders are all higher than 60%.Yanshan powder has higher strength of crystal,and the strength of crystal of Shahe powder is worse.According to test results,the technological parameter should be 2.0% of bentonite content,8.5% of pelletizing moisture,13 min balling time,300 of drying temperature,?1.0m/s of wind speed,80 mm of material thickness,900 of preheat temperature,10 min ?of preheating time,and 1300? of calcination temperature.With the increase of Si O2 content,the compressive strength and dropping strength of the green ball are improved,and the thermal burst temperature decreases,while the compressive strength of pellets reduces.When the Mg O content in pellet is increased,the falling strength and compressive strength of the green ball firstly declines and then rises,while the thermal burst temperature firstly rises and then reduces.The compressive strength of pellets decreases with increasing Mg O content.The thermal burst temperature of the green ball rises when the alkalinity of pellets is increased,while the dropping strength and the compressive strength decline,and the compressive strength reduces.