Using the example of the pellet factory of the Kachkanar Mining and Processing Plant, the technological operations of preparing the charge, its pelletizing and firing are demonstrated.
Panorama of an open pit mining operation.
Explosion in a quarry.
An excavator loads ore into rail cars.
A train with rail cars carries ore to a processing plant.
Iron ore concentrate is transported to production on a conveyor.
Blast furnace.
Territory of the Kachkanar processing plant.
A fountain on the territory.
Iron ore concentrate is fed by a conveyor system from the processing plant to the bunkers of the pellet plant charge department.
Powdered limestone and bentonite are fed to the bunkers by a pneumatic transport system.
The mixture is poured onto the concentrate during transportation on a conveyor.
Bentonite, a special type of clay, a substance that improves the strength properties of pellets.
The concentrate and limestone must have a specific surface area of at least 1500 cm2/g, bentonite at least 5000 cm2/g.
A return in an amount of no more than 2% is added to the charge.
The amount of materials dispensed from the bins is automatically regulated by feeders.
Plate feeder - dispenser.
The material from the bin gets into the feeder neck, then is carried away by a rotating plate to the discharge opening and is cut off by a knife onto the conveyor.
Limestone and bentonite are fed from the bins by screw feeders.
The charge is fed by a conveyor system to the drum mixer.
The drum mixer is a hollow drum installed at an inclination of 2-4 degrees towards the discharge.
Two bandages are fixed motionless on the drum, resting on 4 support rollers.
To hold the drum on the support rollers from possible displacement along the axis, thrust rollers are installed on both end faces of the bandages.
An electric motor rotates the drum.
The charge is intensively mixed when the drum rotates.
It has a strictly defined moisture level.
The charge is fed to the pelletizers by a conveyor system.
Bowl pelletizer.
The pelletizing bowl is mounted on a shaft which rests on the bearings of the central part of the frame.
The frame is attached with a hinge to a cast frame fixed to the foundation.
An electric motor rotating the bowl.
A drive gear is mounted on the output shaft of the electric motor and is engaged with the toothed rim of the bowl.
A mechanism for changing the angle of the bowl.
The bowl pelletizer has knives for forming a layer of bottom and side scallop of a certain thickness.
Rolling of the charge.
Moistening of the charge, if necessary.
A cartoon explaining the pelletizing process.
Raw pellets are fed to the belt of the swinging stacker.
The swinging stacker distributes the pellets in an even layer over the entire width of the roller stacker conveyor.
At the same time, small pellets are screened out, falling through 5 mm gaps between the rollers and washed away by water into the settling tank.
Raw pellets are fed onto the belt of the induration machine.
Cartoon explaining the operation of the induration machine.
Ore enrichment, Pellets, The mixture, Pelletizer
The calcining trolley.
It consists of a split body and grate beams.
The grates are held on the beam shelves and laid with a gap of 6 mm.
The grates are secured with pins from above.
The trolley has running rollers for movement along the rail track, and load rollers for engagement with the drive sprocket teeth, which are involved in the operation when the calcining trolleys enter the drive sprockets.
The rollers are located in the depressions between the teeth.
Electric drive of the calcining trolleys.
Cartoon explaining the operation of the calcining machine.
First, calcined pellets are fed to the calcining belt.
The calcined pellets are used to make a side and bottom bed.
It prevents the holes between the grates from being clogged with raw pellets and prevents the raw pellets from melting to the grates, ensuring their free descent from the belt.
Raw pellets fed to the induration machine belt do not contain solid fuel.
They are fired using high-temperature gases.
Continuation of the cartoon explaining the operation of the induration machine.
There is an unloading device in the tail section of the machine.
Pellets unloaded from the induration trolleys are fed to a bowl cooler for additional cooling.
Separation of fines, which will be returned to the charge preparation section.
Quality pellets are fed to finished product bins.
Monitoring and adjustment of the gas-dynamic and heat engineering parameters of the induration machine is carried out in a semi-automatic mode from the control panel.
Loading pellets into the bin.
A locomotive carries trolleys with pellets to a metallurgical plant.
Movement of trolleys against the background of blast furnace production.
Pellets, Roasting machine