Technology / Technology information

Knowledge of refractory rotary furnace

2021-01-13

Rotary knowledge:

The rotary furnace is a kind of thermal equipment for calcining, roasting or drying granular and powdered Wu Li.

As a conventional kiln type, rotary furnace has existed for hundreds of years, but it is large or super large. It is mainly used in the primary rough processing of powder or mineral materials, such as sintering and calcining of cement clinker. Kaolin preparation of titanium dioxide, rare earth industry processing, etc. Although the output is large, but there are large temperature difference, temperature control accuracy is low, can not seal and achieve accurate atmosphere control and other shortcomings.

The rotary furnace can turn forward and reverse, with fast and slow driving device.

Each positive and negative rotation has a limit position:

The limit position of forward rotation is the slag dumping position, and the limit position of reverse rotation is the position where the copper water casting is finished. In order to operate conveniently, there are also oxidation, reduction position, heat preservation position, feeding position, etc. When the furnace feeding, slag, oxidation, reduction, the use of fast drive; When casting, slow drive is used. At the same time, in order to avoid the accident caused by sudden power failure when the rotary furnace is in the non-thermal position, the accident driving motor is also set to ensure that the rotary furnace can turn to the thermal position safely.

The furnace body of the rotary furnace is a long steel cylinder, lined with refractory materials, the furnace body is supported on several pairs of supporting wheels, and has an inclination of 3% ~ 6%. The furnace is rotated slowly by a gear driven by electric gas. The material is added at the higher end and discharged at the lower end of the furnace. The burner end is injected with fuel (pulverized coal, heavy oil or gas fuel), which is burned in the furnace, and the flue gas is discharged from the higher end (material and flue gas flow counter).

It is mainly used for calcining cement clinker in cement industry, also used for calcining granular and powdery materials in refractories and ceramics industry and drying various raw materials in the above industries. Widely used in chemical industry for drying, dewatering and roasting materials.

Rotary furnace refining process:

The first batch of crude copper water from the converter is first added to the first rotary furnace. After the first batch of material is added, the furnace body is rotated by the motor, and the compressed air is fed into the melt through two REDOX ports for oxidation. The pressure of the compressed air is 0.2~0.4MPa.

After the oxidation, the REDOX port will be transferred to the copper surface to stop blowing, and the heat preservation will wait for the second feeding. After the second feed is added, the second oxidation is carried out until the end point of oxidation. Then, the rotating furnace body emptied the slag from the furnace opening.

After pouring the slag, the furnace body rotates to the original oxidation position, but this time, instead of compressed air, it is reduced liquefied petroleum gas (or heavy oil, ammonia, etc.). After reduction, the furnace rotates so that the copper water is continuously and uniformly released from the pouring port and enters the casting machine through the chute for casting. After casting, the furnace body continues to hold heat, waiting for the fifth batch of material to join the converter.

When the third and fourth batches of materials are reduced or cast in the first rotary furnace, the second rotary furnace has been added. At this point, the rotary furnace has completed a cycle of operation.