Smelting method of high-iron multi-metal zinc concentrate

Abstract

The invention relates to a smelting method of a high-iron multi-metal zinc concentrate. The method comprises the following steps: performing oxygen-enrichment oxidation melting on a zinc concentrate containing 14% to 20% of Fe, 0.03% to 0.10% of In, 0.2% to 0.6% of Cu, 0.2% to 0.6% of Cd, 0.005% to 0.02% of Ag, 0.1% to 0.2% of Sn and 40% to 50% of Zn so as to generate an oxidized flue gas and molten slags; preparing the oxidized flue gas into sulfuric acid; performing reduction smelting on the molten slags in a smelting pool so as to generate a crude zinc alloy, crude copper containing silver and slags; blowing the slags so as to obtain smoke dust and blown slags; returning the smoke dust to be subjected to reduction smelting; selling the blown slags in a market; extracting the copper and the silver from the crude copper containing silver; and performing four-stage distillation on the crude zinc alloy entering an electric-heating graphite vacuum furnace so as to generate a pyrogenic distilled zinc product, a crude cadmium product and a high-indium-tin zinc alloy which is used for extracting indium and tin. The method is reasonable in process, good in comprehensive recovery, high in production efficiency, low in production cost and clean and environmentally friendly in production process.

Description

technical field [0001] The invention relates to a nonferrous metal smelting method, in particular to a method containing Fe14-20%, In0.03-0.10%, Cu0.2-0.6%, Cd0.2-0.6%, Ag0.01-0.02%, Sn0. A method for smelting high-iron polymetallic zinc concentrate with 1-0.2% and Zn40-50%. Background technique [0002] At present, the processing of high-speed iron containing Fe14-20%, In0.03-0.10%, Cu0.2-0.6%, Cd0.2-0.6%, Ag0.01-0.02%, Sn0.1-0.2%, Zn40-50% There are three main methods of extracting zinc and recovering multiple valuable metals from polymetallic zinc concentrates: [0003] The first treatment method is to use the conventional leaching wet process. This process is applied in a zinc smelter in Yunnan. The process adopts zinc concentrate fluidized furnace roasting desulfurization--two-stage countercurrent leaching of zinc calcine with neutral and low acidity--extraction of copper and cadmium by medium and supernatant solution--purification of liquid electrowinning Production...

AI Technical Summary

Problems solved by technology

The main disadvantages of this treatment method are: (1) the primary leaching rate of zinc is low, the processing capacity of the volatilization kiln is large, and a large amount of coal char needs to be consumed; (2) when the volatilization kiln processes the leaching residue, the sulfur dioxide flue gas produced needs to be treated (3) The recovery rate of various valuable metals is low, the recovery rate of indium is 75%, the recovery rate of copper is 80%, the recovery rate of cadmium is 75%, the recovery rate of tin is 50%, and the silver has not been effectively recovered. Serious Affected benefit

The main disadvantages of this method are: (1) the amount of jarosite slag and high leaching slag is large, and a large amount of coke needs to be consumed when the rotary kiln is reduced and volatilized, and the production cost is high; It contains a large amount of sulfate radicals, and a large amount of sulfur dioxide gas is decomposed during the reduction and volatilization process of the rotary kiln. The reduction and volatilization flue gas needs to be absorbed and treated before it can be discharged up to the standard

(3) The smelting recovery rate of indium, silver and tin is low, the recovery rate of indium is 80%, the recovery rate of silver is 30%, and the recovery rate of tin is 60%, which affects the economic benefits

The main disadvantages of this method are: (1) A large amount of electric energy and reduced coal are consumed in the reduction smelting process of the electric furnace, 3200kWh electric energy and 0.8t coke powder are consumed for each ton of crude zinc produced, and the production cost of the smelting process is as high as 3000 yuan / ton Above crude zinc, the production cost of the whole process is as high as 5,800 yuan / ton of distilled zinc products; (2) Since the electric furnace adopts strong reduction smelting, the concentration of carbon monoxide in the process is high, and there are safety hazards of carbon monoxide poisoning and electric furnace bleed gas explosion; (3) Copper-containing There is no good separation and recovery method for the treatment of pig iron, and it is impossible to recycle copper and iron at low cost; (4) The smelting recovery rate of indium, silver, and tin is low. Since electric furnace slag and pig iron are not treated, they account for 20% of the total amount of raw indium metal. More than 35% of the electric slag and indium in pig iron cannot be recovered, and the recovery rate of indium is only 75%; the tin in electric slag and pig iron, which accounts for more than 35% of the total raw material tin metal, cannot be recovered, and the recovery rate of tin is 60%, accounting for Silver in electric furnace slag and pig iron with more than 60% of the total silver metal in raw materials cannot be recovered, and the recovery rate of silver is lower than 40%, which affects economic benefits

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