Magnetization roasting technique system for refractory iron ore powder and roasting technology

The invention belongs to the fields of chemical engineering and metallurgy and in particular relates to a process system which adopts a circulating fluid bed to carry out magnetization roasting on limonite, siderite, sedimentary hematite and other refractory iron ore powder bodies. The process system adopts a high-efficiency low-resistance reactor of the circulating fluid bed to carry out the magnetizing roasting to the iron ore powder body; firstly, roasted tail gas in a combustion chamber releases latent heat of unreacted reducing gas through combustion; secondly, the roasted tail gas exchanges heat with the cold iron ore powder body through a multilevel cyclone preheater to reclaim heat; and finally a fluidizing cooler is adopted to reclaim sensible heat of high-temperature roasting ore. The process system has the advantages of high magnetizing roasting efficiency and full heat reclaiming and utilization in the roasting process and the like, can reduce energy consumption of the refractory iron ore powder body in the process of magnetizing roasting and improve the economical efficiency of the refractory iron ore in the process of magnetizing roasting.