Method for recovering valuable metals by reduction smelting of positive electrode materials of waste lithium iron phosphate batteries

Abstract

The invention discloses a method for reducing and smelting the positive electrode material of a waste lithium iron phosphate battery to recover valuable metals. slag and metal lead, the reduction slag is subjected to water leaching to extract lithium to recover lithium, and the remaining slag phase is collected to recover iron. The present invention utilizes the positive electrode material of the waste lithium iron phosphate battery and cooperates with the waste lead paste to obtain the reduction slag and metallic lead through one-step reduction and smelting. During the reduction process, the lithium is transformed into the form of lithium carbonate, and the carbonized water can be used to extract the lithium for subsequent recovery. The ferrous sulfide produced can be recycled as iron-making raw material, and the synergistic effect of waste and waste is used to realize the comprehensive recycling of resources.

Description

technical field [0001] The invention belongs to the technical field of resource recovery, and in particular relates to a method for recovering valuable metals from lithium battery materials. Background technique [0002] It is estimated that between 2019 and 2023, the average growth rate of my country's lithium-ion battery production will be as high as 16.43%, and my country's lithium-ion battery output will be as high as 28.3 billion in 2023. Such a large amount of lithium-ion battery usage will inevitably bring a large number of waste lithium-ion batteries. In 2018, the total waste of used power batteries (mainly lithium iron phosphate and ternary batteries) in my country was 74,000 tons. Although my country produces a large number of waste lithium-ion batteries every year, according to the statistical report of Gaogong Lithium Battery, the recycling volume of power batteries in my country in 2018 was 5472t, accounting for only 7.4% of the total amount of waste power batt...

AI Technical Summary

Problems solved by technology

However, since the structure of olivine-type lithium iron phosphate is very stable, strong acid needs to be added to destroy its structure, and usually the acid consumption is relatively large, and a large amount of alkali must be added for neutralization in the subsequent steps, resulting in high recovery costs

In addition, the wet recycling process has problems such as producing a large amount of waste liquid, a long process flow and more complicated operations.

The shortcomings of the above-mentioned wet recovery process limit its large-scale industrial application, and it is necessary to develop a recovery method for the positive electrode material of waste lithium iron phosphate batteries with the advantages of high metal recovery rate and low recovery cost.