Method for removing tin from lead bullion by adopting brim stone

Abstract

The invention discloses a method for removing tin from lead bullion by adopting brim stone. The method comprises the following steps of: smelting the tin-containing lead bullion in a smelting device, and then adding sulphur powder into the molten tin-containing lead bullion at the temperature of between 450 and 650 DEG C; fully mixing the sulphur powder and the molten bullion in a stirring way, and preparing SnS from the sulphur powder and the tin in the molten bullion, wherein a specific gravity of the SnS is light, so the SnS can float upward to the surface of the molten bullion to form dross, and then removing the dross; and stirring the molten bullion for 10 to 70 minutes and stopping stirring, and after fishing the dross on the surface of the molten bullion out, performing ingot casting. The refined and tin-removed lead ingot is prepared, and the content of the tin in the lead (wSn) is less than or equal to 0.001 mass percent; and the method reduces lead volatilization, removes alkali vapor and NOX gas, improves the working environment and contributes to physical and psychological health of production operators.

Description

technical field [0001] The invention relates to a method for lead, in particular to a method for removing tin from crude lead. Background technique [0002] The production cost of secondary lead is 38% lower than that of primary lead, and the energy consumption of secondary lead is only 25.1% to 31.4% of that of primary lead. For every ton of secondary lead produced, 1360 kg of standard coal can be saved, solid waste can be reduced by 98.7 tons, and water can be saved by 2.08 tons, reducing sulfur dioxide emissions by 0.66 tons. The general way to regenerate lead is to extract crude lead from various raw materials first, and then use different methods to remove impurity elements in crude lead. For example, crude lead generally contains tin elements, which must be removed in subsequent processes. In order to meet the standard requirements of refined lead, at the same time comprehensively recover the expensive metal tin. [0003] The traditional methods for removing tin from...

AI Technical Summary

Problems solved by technology

The above-mentioned methods in the prior art all remove tin by reacting with other substances to form scum. In the oxidation refining method, the temperature of the material must generally reach 800°C to 900°C to meet the conditions for oxidation reaction , and lead volatilizes seriously at this temperature, causing resources and affecting the working environment. At the same time, this method needs to heat all materials to a temperature above 800°C, which consumes a lot of energy and becomes the main cost of lead regeneration production, resulting in energy consumption. The waste of waste also puts forward higher requirements for equipment, the working environment is harsh, and using lead as a raw material for slagging reaction is also a waste of lead resources

The disadvantage of alkaline refining is that it needs to add a large amount of NaOH, NaNO 3 , the above substances are inevitably heated to form alkali mist and NO during operation X Gas, which seriously pollutes the environment and affects the health of operating workers

More importantly, the tin removal effect of the above two methods is not ideal, and can only reach about 80%. Both of them have the problems of long operation time and high equipment requirements.