Tunnel Kiln Coal Based DRI Plant
Tunnel Kiln history dates back to 1807 when Hoganas first used this process to produce iron powder of 99.9% purity.
When iron ore is mined or processed (in a crusher), lots of fines are generated. Quantity of fines generation is a function of the quality of ore i.e. whether it is hard or soft. Iron ore fines are usually subject to beneficiation and/or pelletisation thereby converting them back into hard rock-like shapes (pellets) with a proper tumbler index. These pellets are then used for making sponge iron.
Rotary kilns have a drawback upon the size and quality of iron ore that can be used. Initially, when the process was first introduced, the ore with an iron content >/= 65% was preferred and the preferred size of ore was 5-18mm. And coal of minimum Ã¢â¬ÅBÃ¢â¬Â grade was required to be used for the solid state reduction or DRI making process. With the passage in time, quality of both iron ore and coal declined and still DRI was being produced. However, the only solution for iron ore fines was beneficiation, if required, and pelletisation. And coal fines virtually lost their commercial value.
While both of the key materials are available in abundance, one of the best means of utilising them is the Tunnel Kiln. Some of the key attributes of the Tunnel Kiln areÃ¢â¬Â¦
- Tunnel Kilns can use soft ore
- Tunnel Kilns can comfortably work with Iron Ore fines (</= -5mm)
- Both Haematite & Magnetite can be converted to sponge iron using Tunnel Kilns
- Tunnel Kilns are comfortable with coal fines and mill scale
- Uniform product quality
- Production cost from Tunnel Kilns is lower than that from rotary kilns
- Extremely low on environmental pollution
72, Palodia, (Via Thaltej), Ahmedabad, Gujarat, 382115, India