Effect of dewpoint of decomposed ammonia on reduced iron powder by secondary reduction

For the dry reducing gas entering from the discharge end, the water vapor content is required to be less than 4%;For the raw iron powder with carbon content up to 0.6%, the moisture vapor content of the humidifying gas through the feed end is required to be more than 6%, which can not only ensure the effective deoxidation of iron powder in the second half of the heating section and no reoxidation in the cooling section, but also ensure the large number of decarburization of iron powder in the first half of the heating section.

Fine reduction temperature is 800 ~ 950, for example, the heating time for in the second half of the first half of 10 ~ 150 min 30 ~ 170 min conditions, using the above two kinds of different decomposition of ammonia atmosphere and into the way, can make the carbon containing 0.1% ~ 0.6% metal iron 93% ~ 98% of the raw materials of iron powder reduction of carbon is less than 0.01% hydrogen loss value is less than 0.2% of total iron is equal to or greater than 99.0% high quality iron powder, the briquette density can be up to 6.76 g/cm3.