A method for removing impurities from thick lead paste

Abstract

The invention relates to the technical field of impurity removal, and discloses a method for removing impurities from crude lead paste. The method includes: adding the crude lead paste to water, stirring and dispersing evenly to obtain a precursor a; adding sulfuric acid to the precursor a, Perform pH adjustment to obtain precursor b; add non-ionic surfactant to precursor b and stir to obtain precursor c; sieve precursor c with a slurry vibrating sieve to remove impurities to obtain precursor d; Precursor d undergoes natural sedimentation to obtain lead paste. The use of non-ionic surfactants can avoid the problems of poor dispersion efficiency and blockage of screens under acidic conditions, and the use of vibrating screens with suitable apertures can efficiently separate impurities to achieve the purpose of purifying waste sulfuric acid; plastic sheets, The removal rate of physical impurities such as glass fiber and lead grid can reach more than 99.95%.

Description

technical field [0001] The invention relates to the technical field of impurity removal, in particular to a method for removing impurities from thick lead paste. Background technique [0002] Waste lead paste contains impurities such as plastic flakes, glass fibers, and lead grids. If these impurities are not separated, these impurities will cause many problems in the subsequent processing process. Fibers and plastics may cause excessive levels of dioxin in the exhaust fumes; they will also introduce more impurities into the subsequent wet recycling of lead paste. Especially the waste lead paste produced by lead-acid batteries, because lead-acid batteries are currently the battery with the largest production volume and the widest use of all kinds of batteries in the world; the annual sales of lead-acid batteries in my country have reached more than 10 billion yuan , is widely used in various fields such as telecommunications, finance, UPS, radio and television, electric powe...

AI Technical Summary

Problems solved by technology

Domestic lead-acid battery recycling management is not optimistic. In terms of recycling, battery collection, dismantling, and secondary lead smelting process all produce serious environmental pollution.

[0003] CN201810379427.5 discloses a method of wet recovery and removal of impurities from waste lead paste and preparation of high-purity lead compounds, desulfurization at room temperature, and then reacting with acid leaching agent mixed with hydrogen peroxide reducing agent, adjusting pH value, filtering, Then the liquid phase reaction is converted to prepare the solid phase lead compound, mainly to overcome the difficult problem of high content of impurities Ba and Fe elements, which are difficult to remove, but it has no effect on impurities such as plastic sheets, glass fibers, and lead grids.

[0004] At present, our country lacks an effective method for finely sorting the coarse lead paste after mechanical crushing and sorting. Due to the high viscosity of the lead paste, the mesh is blocked in the actual screening process, making the screening impossible; Electrolyte sulfuric acid solution, the prepared lead paste slurry usually has a certain acidity, which makes it difficult to use ionic surfactants to modify the slurry. Therefore, it provides an efficient and simple method for the fineness of coarse lead paste after mechanical crushing and sorting of waste lead-acid batteries. Sorting method is very important