A kind of pelletizing method of pellets used in rotary hearth furnace direct reduction production process

Abstract

The invention discloses a pelletizing method of pellets for a direct reduction production process of a rotary hearth furnace. The pelletizing method comprises the following steps: controlling the water content of high-temperature asphalt powder to be not more than 5wt%, controlling the water content of iron ore concentrate to be not more than 8wt%, and uniformly mixing the high-temperature asphalt powder, the iron ore concentrate and a carbon-containing supplementary reducing agent to obtain a mixture, wherein the mixing amount of the high-temperature asphalt powder is not lower than 3wt% of the total amount of the mixture, and the mixing amount of the carbon-containing supplementary reducing agent accounts for 0-25wt% of the total amount of the mixture; pelletizing the mixture to obtain the pellets, wherein the water content of the mixture is controlled at 5-6.5wt%, and the temperature of the mixture is 90-130 DEG C. By adopting the pelletizing method disclosed by the invention, the problem of high preparation and production cost of a traditional pelletizing process is solved, the pelletizing method can be used for simultaneously assisting in solving the process defect that ash and other impurities are introduced when an inorganic adhesive is adopted for pelletizing, and the pelletizing method further has good popularization and application prospect.

Description

technical field [0001] The invention belongs to the technical field of metallurgy, and more specifically relates to a pelletizing method for pellets used in a rotary hearth furnace direct reduction production process. Background technique [0002] With the increasing shortage of resources, especially the scarcity of high-quality iron-containing raw materials and coking coal, the survival and development of traditional blast furnace smelting iron and steel enterprises have been greatly challenged. However, the non-blast furnace ironmaking technology with less resource constraints, greater flexibility, and short process has attracted more and more attention. The attention and application of it to the production of direct reduction of iron ore has achieved rapid development. [0003] In actual production, iron concentrate resources including vanadium-titanium magnetite are directly reduced by rotary hearth furnace. However, due to the overall low grade of iron concentrate in m...

AI Technical Summary

Problems solved by technology

[0004] Since the preparation process of carbon-containing pellets requires an additional binder, if the binder is an inorganic type, it will increase the production cost of the pellets and increase the processing burden of the subsequent process, resulting in unnecessary processing capacity or power consumption. increase; if the organic type adhesive is used, the cost will increase even more due to the influence of its overall higher price