Harmless and resourceful treatment method for waste lithium battery electrolyte

Abstract

The harmless and resource recycling treatment method comprises the following steps that waste lithium batteries and conductive graphite powder are mixed and stirred for material discharging, the discharged waste lithium batteries are screened and recycled, and the conductive graphite powder is recycled; under the protection of carbon dioxide or inert gas, heating the discharged waste lithium battery, and condensing and recycling the volatilized electrolyte; the recycled electrolyte is subjected to pyrolysis treatment in carbon dioxide or inert gas, and after pyrolysis is completed, pyrolysis gas is subjected to defluorination treatment at the corresponding temperature through carbon dioxide or inert gas; and carrying out secondary pyrolysis treatment on the defluorination pyrolysis gas flow, and finally cooling and storing the obtained pyrolysis gas to be reused as a chemical synthesis raw material gas resource. According to the method, safe, environment-friendly and efficient utilization of the electrolyte can be realized, and environmental hazards caused by direct waste of the electrolyte in the waste lithium battery are avoided.

Description

technical field [0001] The invention belongs to the technical field of recycling waste lithium batteries, and in particular relates to a harmless and resourceful treatment method for electrolyte solution of waste lithium batteries. Background technique [0002] Energy is an important material basis for economic and social development. Coal is the main source of energy in my country and the most important source of carbon emissions. In order to solve the global climate change problem caused by carbon dioxide emissions and realize the sustainable development of human living environment, it is imperative to reduce carbon dioxide emissions and increase the capacity of new energy consumption. Lithium batteries are one of the important carriers of new energy sources. Therefore, in recent years The demand for lithium batteries is growing rapidly. At the same time, since the service life of lithium batteries is about 3 to 5 years, a large number of lithium batteries have been decom...

AI Technical Summary

Problems solved by technology

At the same time, since the service life of lithium batteries is about 3 to 5 years, a large number of lithium batteries have been decommissioned

Waste lithium batteries contain toxic substances such as heavy metals and electrolytes, if not properly disposed of, it will cause serious environmental pollution and waste of resources

[0003] The electrolyte accounts for about 10-15wt% of the weight of the lithium battery. Since the electrolyte is infiltrated with the positive and negative electrodes in the battery cell during the charging and discharging process, the content of the liquid electrolyte in the lithium battery after use is reduced. , and the composition of the electrolyte changes greatly, making it difficult to separate and reuse the electrolyte in the waste lithium battery

Among the existing treatment technologies for the electrolyte in waste lithium batteries, on the one hand, pyrolysis treatment is to directly carry out pyrolysis treatment on waste lithium batteries, so that the electrolyte is gasified and discharged. It consists of steps such as pyrolysis, condensation collection, and tail gas treatment. The process is complicated and the electrolyte has not been effectively treated; on the other hand, there are problems such as the release of dioxins and the waste of electrolyte resources by directly incinerating waste lithium batteries.

Wet treatment mainly uses organic solvents to extract the electrolyte from the broken lithium batteries, and then distills the extracted mixed solution to recover the organic solvents for recycling; due to the complex composition of the electrolyte in the waste lithium batteries, existing Wet treatment can only separate the electrolyte from the lithium battery, but cannot realize resource utilization and harmless disposal of the electrolyte

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