CHARP工艺过程中的硫行为及硫控制

 对转底炉煤基热风熔融炼铁工艺(CHARP)含碳球团还原熔分过程中硫的分配、硫的行为以及如何降低或控制珠铁中的硫含量进行了实验研究。结果表明，除了控制原料中以及垫底料中硫含量以外，应尽量缩短珠铁形成以后其在炉内的停留时间，防止液态铁从垫底料中吸硫；垫底料中混合适量的固硫剂有利于降低珠铁中硫含量。含碳球团中碱度对珠铁降硫作用不大，添加适量的Na2CO3和MnO2对珠铁具有较显著的降硫效果。氧化性气氛可促进含碳球团中硫的挥发。

Behaviour of Sulphur and Control of Sulphur in CHARP Process

The behavior of sulfur,sulfur distribution and methods of decreasing or controlling the sulfur content in iron bead have been investigated during the reduction and melting in ore/coal composite pellets in the coal hot-air rotary hearth furnace process(CHARP).From experimental results,it has been concluded that,in addition to controlling the sulfur content in raw materials and hearth layer material,residence time of molten iron bead in the furnace should be shorten after its formation to prevent the absorption of sulfur from hearth layer material,the addition of sulfur fixation agent to hearth layer material is in favor of the decrease of sulfur in iron bead.The experiment demonstrates that the basicity has less effect on the decrease of sulfur in iron bead,while the addition of Na2CO3 or MnO2 in ore/coal composite pellets has a remarkable effect on that.The oxidation atmosphere can promote the volatilisation of sulfur in pellets.