Tratec Solutions has delivered raw material handling to several Si process plants in Norway. Raw material handling in this context means automatic delivery of raw materials to melting furnaces using a given mixing order. The material handling system consists of different machine types, connected in a line. The system starts outdoors at the receiving silo and ends at the pipe feeders that deliver raw material directly to the furnaces.

Overview of the different machine types

1. RECEIVING SILO WITH VIBRATION FEEDER

The receiving silo is designed to receive different types of material to the day silos from a front loader. The vibrating feeder doses the material from the receiving pocket to a belt conveyor with conveyor belt.

2. BELT CONVEYOR WITH CARRIER BELT

The belt conveyor receives material from the vibrating feeder, transports the material up to the belt conveyor in the conveyor bridge, which takes the material into the factory building.

3. CONVEYOR BRIDGE

The belt conveyor receives material from the belt conveyor with carrier belt and transports the material up to the next belt conveyor located above the day containers.

4. BELT CONVEYOR OVER MATERIAL SILOS

This intermediate belt conveyor receives material from the belt conveyor in the conveyor bridge and transports it to the shuttle conveyor.

5. SHUTTLE CONVEYOR OVER MATERIAL CONTAINERS

The shuttle conveyor handles all types of different raw materials and moves to the right silo on signal from the control system. All belts on the shuttle conveyor are reversible to serve all 24-hour silos. Stationary platforms are installed on both sides, providing good access for maintenance and inspection of the shuttle conveyor and the belt conveyor above.

6. WEIGHING SYSTEM UNDER 24-HOUR SILOS

The weighing system underneath the silos consists of electromagnetic vibratory feeders and weighing hoppers. These machines are used to empty the silos in a given sequence, creating several layers of different materials on the conveyor below, called a «sandwich belt».

7. SANDWICH BELT CONVEYOR

The sandwich belt transports the raw material mix to a Belt Conveyor with a carrier belt that lifts the material up to the conveyor system above the ovens, which distributes the material mix to the desired oven silo.

8. BELT CONVEYOR WITH CARRIER BELT

This conveyor receives material from the Sandwich belt and transports the material 20m above ground level. Flexowell is equipped with an impact roller installed above the belt. The impact roller ensures that the remaining material is released from the belt and into the discharge chute.

9. SHUTTLE CONVEYOR SYSTEM ABOVE KILN SILOS

The first belt conveyor after the conveyor belt is reversible and can deliver material to the left or right shuttle conveyor. The shuttle conveyor travels to the desired oven container, which is automatic and controlled by process requirements. The conveyor is equipped with platforms on both sides for maintenance and inspection access.

10. FEEDING SYSTEM FOR KILN SILOS

The feeding system consists of storage silos, vibratory feeders and pipes for the controlled feeding of raw material that is mixed into the furnace process. Each position has its own storage silo, vibrating feeder and pipe. The feeders rotate to achieve a good distribution of the material mixture around the electrodes.

The 10 kiln silos are placed in two rows with 5 silos on each side of the kiln. The furnace silo for the centre tube is larger since 25-30% of the total furnace consumption goes through the centre tube. This allows correction material to be quickly loaded to the desired electrode(s).

The vibratory feeders transport material from the kiln silo outlet into the rotating feed pipe - one feeder per silo/pipe. The vibratory feeders are driven by two unbalance motors. The vibrating feeder is supported on coil springs. The weight of the vibratory feeder is precisely matched to the vibration motors to optimise transport speed and service life.

11. BRIKETT SYSTEM

The system consists of 2 docking stations. A docking station with a heating and ventilation system, and a feeding station with a vibrating feeder, conveyor and rotating discharge chute that can deliver briquette material to 3 electrodes.