Reduction kiln

1.Product introduction
Reduction rotary kiln is the core equipment for high temperature reduction roasting of metal oxides ( such as iron concentrate, laterite nickel ore, manganese ore, ilmenite, etc. ) in reducing atmosphere. The equipment is based on the traditional rotary kiln, combined with the reduction roasting process to optimize the design of special requirements such as atmosphere control, temperature gradient, and material residence time. It can efficiently complete the reduction reaction of metal oxides in minerals and generate direct reduced iron ( sponge iron ), ferronickel, reduced manganese powder and other products. The cylinder of the equipment is made of high temperature resistant steel plate, which is lined with refractory materials with thermal shock resistance and corrosion resistance. It is arranged obliquely as a whole, equipped with sealed feed, discharge device and reduction atmosphere control system. It has stable operation, low energy consumption and uniform product quality.

2.Working principle
The reduction rotary kiln uses solid reducing agent ( such as pulverized coal, coke powder ) or gas reducing agent ( such as CO, H2 ) as the medium to create a reducing atmosphere in the kiln. The material is fed into the kiln by the kiln tail ( high-end ) feeding device, and the reducing agent is added in a certain proportion from the kiln tail or kiln head. The cylinder rotates slowly under the drive of the transmission device, and the material rolls along the circumferential direction and moves from the kiln tail to the kiln head ( low end ) along the axial direction.
The fuel is injected into the kiln from the kiln head through the burner to burn, providing the heat required for the reduction reaction. The temperature in the kiln forms a gradient distribution along the axial direction : the material in the preheating section is heated and dried, and the main reduction reaction occurs in the reduction section at a suitable temperature. The metal oxide is reduced to metal elemental or low-valent oxide by carbon or CO and H2 in the reducing agent to form metallized products. The products in the cooling section are gradually cooled down and then discharged from the kiln head into the subsequent cooling, magnetic separation or separation process. The reducing flue gas generated in the kiln is discharged from the kiln tail, and is discharged after treatment by the dust removal and waste heat recovery system.