Method for adopting oxygen-enriched vortex bath smelting furnace to treat zinc leaching residue

Abstract

The invention discloses a method for adopting an oxygen-enriched vortex bath smelting furnace to treat zinc leaching residue. The oxygen-enriched vortex bath smelting furnace comprises a furnace body and multiple spray guns, a furnace cavity has a round cross section, multiple spray gun inserting holes are distributed in the side wall of the furnace body at intervals circumferentially, and the spray guns are inserted into the spray gun inserting holes and deviate from circle center of the round cross section of the furnace cavity along a same direction. The method includes the following steps: placing the zinc leaching residue and reducing coal after being automatically burdened into the furnace body through a feeding port; adopting the spray guns to spray fuel and oxygen-enriched air into a bath in the furnace by a certain angle deviating from circle center to generate vortex in the bath, decomposition of the zinc leaching residue and reduction volatilizing of zinc oxide are accelerated, and low-zinc-content smelting slag smaller than 8% in zinc content and smoke are generated; feeding the low-zinc-content smelting slag into a depletion furnace for deep depletion to obtain depleted slag small than 2.5% in zinc content. According to the method, the furnace body is long in service life, hearth efficiency is high, energy consumption is low, and operating environment is good.

Description

technical field [0001] The invention relates to a nonferrous smelting method, in particular to a method for treating zinc leaching slag with an oxygen-enriched vortex molten pool melting furnace. Background technique [0002] Modern zinc smelting production processes are mainly divided into two categories: pyrometallurgy and hydrometallurgy. The hydrometallurgy zinc smelting process is the mainstream zinc smelting process in the world today, accounting for more than 85% of the total zinc smelting in the world. The leaching process will produce leaching slag. The leaching slag produced by different processes has different components, but Usually contain valuable metals such as zinc, lead, copper, gold, silver, etc., which need to be recycled. In addition, China's "National Hazardous Waste List" has included non-ferrous metal wet smelting waste residues in it. Zinc and lead in the leaching residue belong to the first class of pollutants, and they mostly exist in the form of s...

AI Technical Summary

Problems solved by technology

In addition, China's "National Hazardous Waste List" has included non-ferrous metal wet smelting waste residues in it. Zinc and lead in the leaching residue belong to the first class of pollutants, and they mostly exist in the form of soluble sulfate in the leaching residue, such as If it is not treated, it will easily cause the following three environmental hazards: ①The heavy metals in the leaching slag enter the surface water body and groundwater body with rainwater, causing water environment pollution

② After the leaching slag is naturally air-dried, the heavy metals in it enter the atmosphere with the dust, causing air pollution

③The leached slag enters the soil without harmless treatment, causing soil pollution, which in turn pollutes crops and groundwater

However, there are still obvious shortcomings in this process, which are mainly reflected in: first, the operation rate is low

Due to periodic maintenance of the kiln lining and kiln shutdown due to accidents during production, the annual effective operating rate is less than 80%

Second, the comprehensive energy consumption is high

Rotary kiln volatilization needs to add ~50% coke powder, resulting in high production energy consumption

Third, due to the low operating rate, the processing capacity is relatively small

Fourth, the silver recovery rate is low

However, this process belongs to the category of side blowing molten pool smelting

Especially the width of the furnace body, due to the limitation of the blowing and agitation distance of the side blowing lance, the width cannot be greatly adjusted, usually 2.2-2.8 meters, and it is difficult to increase the size of the furnace.

This will cause heat dispersion in the furnace, and it is difficult to maximize the strength of materials such as smelting zinc leaching slag; at the same time, with the extension of the length of the side wall, the expansion of the refractory bricks will increase the risk of brick failure due to stress inconcentration.

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