Iron ore pellets are being increasingly favored in modern blast furnaces. The proportion of pellets in the burden for iron making is increasing due to properties such as higher density, uniform granularity, higher grade iron, good reducibility, etc. Quality of pellet is uniform and suitable for transportation over long distance. Pellet is a good raw material for Sponge iron making too.

1. Traveling grate pelletizing process
- Characteristics:

• The main process i.e.: of drying, pre-heating, induration and cooling, are all included in one unit
• Suitable for large-capacity production.
• Highly adaptable to raw material. hematite, magnetite or mix can be used as feed material. Compared to grate-kiln, it is better suited to hematite.
• Reliable equipment.
• Fuel: Furnace oil and gaseous fuel

1-Hopper for side and hearth layer material; 2-Roller distributor; 3-Traveling grate; 4-Fan; 5-Primary air main; 6-Recuperation fan; 7-Primary air hood; 8-Furnace oil combustion chamber; 9-Blast drying air hood; 10-Downdraught drying air hood; 11-Preheated roasting hood; 12-Soaking air hood; 13-Primary air hood; 14-Secondary air hood; 15-Pellet hopper; 16-Vibrating screen; 17- Wind box; 18-Chimney; 19-Waste air fan; 20-Recirculation fan; 21-Cooling fan

2. Traveling grate-Rotary Kiln (Grate-Kiln) pelletizing process
- Characteristic:

• Good adaptability to raw materials: both magnetite or hematite concentrate can be used;
• Good adaptability to different fuels like Pulverized coal, BF gas, mixed gas of BF/coke oven gas and converter gas;
• Low power consumption and utilization of secondary energy; 

- Scale of Design

•  SSIT can design and supply pellet plant with capacity of 0.3 MT/A, 0.6 MT/A, 1 MT/A, 1.2 MT/A and 2 MT/A

- Sketch of 0.3 MTPA Grate-kiln palletizing process

Process Description

The process starts at raw feed storage and goes through a proportioning building, a concentrates drier, damp mill, balling disc  and green ball Screening & Distribution System. The green ball is then conveyed to the traveling grate. After drying and pre-heating on the grate, the green balls are discharged into the rotary kiln through a scraper and feeding chute. During the 30-35 minutes retention in the kiln, chemical reactions are completed on the pellets with physical changes resulting in a strength of 2200N/pellet (minimum). Then the hot pellet at approx. 1250 deg C is discharged from the rotary kiln and fed into a circular cooler.

 The Quality Standard of Acid Pellet