One-step oxidation smelting, reduction smelting and slag fuming and volatilization methods for lead sulfide concentrate

Abstract

The invention relates to non-ferrous metal metallurgy technology, in particular to the pyrometallurgy technology of lead sulfide concentrate. The process method is to successively carry out three smelting processes of oxidation smelting, reduction smelting and fuming volatilization in the same metallurgical furnace to smelt lead sulfide concentrate, and smelt crude lead, zinc fume and discardable slag in one step. In the oxidation smelting stage, after the feed reaches the set amount, the lead oxide slag is not released, and the high-temperature liquid slag is directly used in the furnace to transfer to the reduction stage of the lead oxide slag, and the smoke generated by oxidation smelting and reduction smelting is returned to the furnace for smelting. After the reduction is completed, all the crude lead is released, and the high-temperature liquid slag remains in the furnace, and it enters the slag fuming stage, and the zinc fume dust from the slag fuming is recovered and enters the next smelting cycle. The heat of the slag in the invention is fully utilized, and the energy-saving effect is obvious. The raw material preparation of the method is simple, the reducing agent only needs ordinary anthracite, and part of the fuel that needs to be supplemented in the reducing section and the fuming section is pulverized coal, which is low in value and easy to obtain.

Description

technical field [0001] The invention relates to non-ferrous metal metallurgy technology, in particular to the pyrometallurgy technology of lead sulfide concentrate. Background technique [0002] The smelting methods of lead sulfide ore can be summarized into two categories: traditional lead smelting method and direct lead smelting method. The traditional lead smelting method is the sintering machine-blast furnace smelting method; the direct lead smelting method is to cancel the sintering process of the lead sulfide concentrate, and the raw concentrate is directly smelted in the furnace. For many years, the traditional method has been the main production method of lead. However, with the continuous improvement of human awareness and requirements for environmental protection and energy conservation, the shortcomings of the traditional lead smelting method have become increasingly prominent. Many lead smelters in the world have gradually adopted direct lead smelting methods to ...

AI Technical Summary

Problems solved by technology

[0004] Traditional lead smelting methods have disadvantages that are difficult for people to continue to accept: the amount of flue gas produced by sintering machines and blast furnaces is large, and SO2 concentration is low, generally less than 4%, and it is difficult to treat and utilize economically, so that it will cause serious pollution to the environment; a large amount of oxidation reaction heat is not fully utilized in the sintering process, and the sintered block is smelted in the blast furnace after cooling. A large amount of expensive metallurgical coke is consumed, and energy consumption is high; the process flow is long and there are many equipments; there is a lot of material turnover; the sintered agglomerate is broken back, the mixture is sintered, and the blast furnace smelting operation produces lead-containing dust, lead-containing steam and SO2 smoke, serious pollution at low altitudes, poor operating environment, poor labor and industrial sanitation conditions, and great harm to the health of employees

The slag (lead-rich slag) produced by the smelting furnace is released regularly, and needs to be cooled and crushed to a certain particle size, and then reduced to smelted in the blast furnace, and expensive metallurgical coke is added; the reaction heat is not fully utilized, and the energy consumption is still high

The slag produced by the blast furnace is sent to the fuming furnace for fuming to further recover valuable metals such as zinc, and the energy consumption is high

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