Method for preparing high-grade secondary zinc oxide in rotary kiln through oxygen enriched combustion

Abstract

The invention is a method for preparing high-grade zinc oxide by oxygen-enriched combustion in a rotary kiln. The steps are: preparation of zinc-containing materials: processing zinc-containing raw materials from various sources to make them meet the requirements of zinc-containing 6-20%, Moisture content of 10-20% is required, and the particle size is less than 1cm; Mixture ingredients: mix fuel with zinc-containing materials, the fuel accounts for 25-35% by mass in the mixture or the calorific value of the mixture is 1500-2000 Kcal / kg; put the mixture into the rotary kiln, and blow in oxygen-enriched air for combustion, so that zinc is enriched in the form of zinc oxide in the dust, and iron is enriched in the kiln slag; the dust is collected to obtain secondary zinc oxide products. The invention aims at the complex material rotary kiln volatilization process, first solves the combustion control problem, ensures the combustion temperature, and the kiln condition is stable, and then performs the fuel ratio according to the heat required for the reaction, thereby improving the kiln condition, increasing the combustion efficiency, and the rotary kiln treatment Quantity, secondary zinc oxide powder quality and recovery rate, while reducing energy consumption and saving costs.

Description

technical field [0001] The invention relates to a method for preparing high-grade zinc oxide by oxygen-enriched combustion in a rotary kiln, and belongs to the technical field of energy-saving and comprehensive recovery of low-grade zinc-containing materials. Background technique [0002] In the process of traditional zinc sulfide concentrate smelting and extraction of metal zinc, most of the leaching slag adopts pyrolysis volatilization and enrichment method to produce zinc oxide powder. However, in actual production, various zinc-containing secondary resources have zinc-containing grades. Low and high impurity content, the rotary kiln is also used to volatilize and enrich zinc. There are many types of zinc-containing secondary resources, such as smoke dust, leaching slag, pyrotechnical slag, etc., and the shape is powdery, muddy, massive, etc., and the water content fluctuates greatly, resulting in a large temperature change during the combustion and volatilization process...

AI Technical Summary

Problems solved by technology

There are many types of zinc-containing secondary resources, such as smoke dust, leaching slag, pyrotechnic slag, etc., and the shape is powdery, muddy, massive, etc., and the water content fluctuates greatly, resulting in a large temperature change during the combustion and volatilization process. The kiln condition is difficult to control, the rotary kiln is frequently closed, the energy consumption is high, the recovery rate is low, the operation rate is low, and the quality of the secondary zinc oxide produced is poor