Method for producing zinc oxide and iron by treating zinc ore (slag) in reduction rotary kiln

Abstract

The invention discloses a production method for producing commercial zinc oxide of a grade of more than or equal to 85 percent from kiln tail and sponge iron and baking-free bricks from kiln head by directly reducing iron-containing zinc ore (slag), reduction coal and lime in a rotary kiln. The process flow of the production method comprises the following steps: raw material preparation, direct reduction in rotary kiln, cooling in cooling kiln, collection at kiln tail and refining pelletizing at kiln head. The required coal particle size is less than 15 millimeters, the particle size of lime is less than 2 millimeters, the coal is burnt by primary air and secondary air, the calcining time is 1.5 to 8 hours, the calcining temperature in the kiln is controlled to be 50 to 1,200 DEG C, materials in the cooling kiln are cooled by water and wind to below a normal temperature of 38 DEG C, the materials are selected and pelletized, the commercial zinc oxide powder is produced at kiln tail, and the commercial sponge iron and baking-free bricks are produced in the kiln head. The method of the invention is simple, energy-saving, emission-reducing, free from waste slag and low in production cost, can produce various products with high quality, represents high degree of mechanization, is favorable for industrial large-scale production, has a large market, is very competitive and environmentally-friendly. The method can create great economic, social and environment-protection effects and solves the economic and technical problems faced by manufacturers of the same industry at home and abroad.

Description

technical field [0001] The invention relates to a method for using a reduction rotary kiln to process iron-containing zinc oxide ore (zinc oxide slag) at the kiln tail to produce commercial zinc oxide, and at the kiln head to produce commercial sponge iron and unburned bricks. Background technique [0002] There are a lot of iron-containing zinc oxide ore (iron-containing zinc oxide slag) in my country. The traditional treatment method is: use an oxidation rotary kiln to add a reducing agent, burn and volatilize the zinc oxide ore (slag) (very easy to kiln dead furnace), dust collection and recovery Zinc oxide powder, iron-containing and non-ferrous metal slag are discharged from the kiln head into the pool for water crushing, and then sent to the slag yard to accumulate as waste slag. This not only increases the amount of waste slag, seriously pollutes the environment, but also wastes valuable metals. In my country, hundreds of millions of tons of such waste residues are pile...

AI Technical Summary

Problems solved by technology

[0002] There are a lot of iron-containing zinc oxide ore (iron-containing zinc oxide slag) in my country. The traditional treatment method is: use an oxidation rotary kiln to add a reducing agent, burn and volatilize the zinc oxide ore (slag) (very easy to kiln dead furnace), dust collection and recovery Zinc oxide powder, iron-containing and non-ferrous metal slag are discharged from the kiln head into the pool for water crushing, and then sent to the slag yard to accumulate as waste slag. This not only increases the amount of waste slag, seriously pollutes the environment, but also wastes valuable metals. In my country, hundreds of millions of tons of this kind of waste residue have been piled up, and there is no recycling

Due to the small number of products and high production costs (losses), production was forced to stop

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