阅读说明：本技术 一种利用超声强化萃取法分离回收废旧动力锂电池中电解液的方法 (Method for separating and recycling electrolyte in waste power lithium battery by using ultrasonic enhanced extraction method ) 是由 李兰兰 王甲琴 陈天翼 张明兰 保毓鹏 柴艮风 王杰伟 吴明敏 于 2019-09-12 设计创作，主要内容包括：本发明属于废旧电池回收技术领域,公开一种利用超声强化萃取法分离回收废旧动力锂电池中电解液的方法。其特征步骤包括：(1)将废旧动力锂电池在惰性气体保护、密闭状态下进行拆解、破碎得到废旧电池碎料。(2)将废旧锂电池碎料进入萃取设备中,通过超声强化萃取实现电解液的萃取分离。(3)萃取后电解液、主萃取剂、辅助萃取剂通过蒸发、冷凝的方式进行分离回收,回收后循环利用于萃取工序。有益效果：本发明适用范围广,高效萃取、分离动力锂离子电池中的电解液,同时将主萃取剂、辅助萃取剂通过蒸发、冷凝后回收循环再利用。整个过程没有污染性气体、液体和固态废弃物产生,真正实现三废零排放,对环境友好,易实现大规模工业应用。(The invention belongs to the technical field of waste battery recovery, and discloses a method for separating and recovering electrolyte in waste power lithium batteries by using an ultrasonic enhanced extraction method. The method is characterized by comprising the following steps: (1) and disassembling and crushing the waste power lithium battery under the protection of inert gas in a closed state to obtain the crushed waste battery. (2) And (3) feeding the waste lithium battery crushed aggregates into extraction equipment, and realizing the extraction and separation of the electrolyte through ultrasonic enhanced extraction. (3) And separating and recovering the extracted electrolyte, the main extracting agent and the auxiliary extracting agent in an evaporation and condensation mode, and recycling the recovered electrolyte, the main extracting agent and the auxiliary extracting agent for the extraction process. Has the advantages that: the invention has wide application range, efficiently extracts and separates the electrolyte in the power lithium ion battery, and simultaneously recycles and recycles the main extractant and the auxiliary extractant after evaporation and condensation. The whole process generates no polluting gas, liquid and solid wastes, really realizes zero discharge of three wastes, is environment-friendly and is easy to realize large-scale industrial application.)

1. A method for separating and recovering electrolyte in waste power lithium batteries by using an ultrasonic enhanced extraction method is characterized by comprising the following steps of:

a. carrying out charged crushing on the waste lithium battery under the protection of inert gas and in a closed atmosphere to obtain waste battery crushed materials;

b. b, putting the battery crushed aggregates obtained in the step a into ultrasonic enhanced extraction equipment, extracting and separating to obtain organic matters containing electrolyte and the battery crushed aggregates, and using a main extracting agent and an auxiliary extracting agent for ultrasonic enhanced extraction;

c. and c, evaporating and condensing the organic matters containing the electrolyte obtained in the step b to respectively obtain the electrolyte, the main extracting agent and the auxiliary extracting agent, and recycling the main extracting agent and the auxiliary extracting agent after evaporation and condensation for the extraction process.

2. The method for separating and recovering the electrolyte in the waste power lithium battery by using the ultrasonic enhanced extraction method as claimed in claim 1, which is characterized by comprising the following steps of: the inert gas used in the step a is nitrogen or argon or carbon dioxide, and the size of the crushed material is 20mm by 20 mm.

3. The method for separating and recovering the electrolyte in the waste power lithium battery by using the ultrasonic enhanced extraction method as claimed in claim 1, which is characterized by comprising the following steps of: and in the step b, the main extracting agent is ethyl propionate and ethylene carbonate, and the auxiliary extracting agent is N-methyl pyrrolidone.

4. The method for separating and recovering the electrolyte in the waste power lithium battery by using the ultrasonic enhanced extraction method as claimed in claim 1, wherein in the step b, the ultrasonic enhanced extraction temperature is normal-temperature environment temperature, the extraction time is 5 ~ 120min and the extraction flow ratio is 1:1 ~ 5.

5. The method for separating and recovering the electrolyte in the waste power lithium battery by using the ultrasonic enhanced extraction method as claimed in claim 1, wherein the evaporation temperature in the step c is 50 ~ 80 ℃.

6. The method for separating and recovering the electrolyte in the waste power lithium battery by using the ultrasonic enhanced extraction method as claimed in claim 1, which is characterized by comprising the following steps of: and c, crushing the battery crushed materials obtained in the step b again, carrying out air flow separation and magnetic separation to recover electrode powder, copper aluminum foil and a diaphragm.

Technical Field

The invention relates to the field of waste lithium ion battery recovery, in particular to a method for separating and recovering electrolyte in waste power lithium batteries by using an ultrasonic enhanced extraction method.

Background

Under the guidance and promotion of national policies, the new energy automobile industry in China develops rapidly. The output and sales of pure electric vehicles and plug-in hybrid vehicles are expected to exceed 200 million in 2020, and set targets in development plans of energy-saving and new energy vehicle industries released by state hospitals (2012-2020) are reached. Depending on the age of the battery, 5-8 years, the battery will begin to enter a discard burst period in 2018. According to the prediction of the research center of automobile technology in China, the total scrappage of the lithium battery in 2020 reaches 32.2Gwh, which is about 50 ten thousand tons; the total scrappage in 2023 will reach 101Gwh, about 116 ten thousand tons.

An electric automobile averagely uses 50kg of positive electrode material, 40 kg of negative electrode material and 40 kg of electrolyte, and 5000 tons of positive electrode material, 4000 tons of negative electrode material and 4000 tons of electrolyte are promoted in 2014-2018 according to the fact that 10 ten thousand lithium battery electric automobiles are put into China in 2009-2011. If 200 ten thousand lithium battery electric automobiles are put into the automobile in 2020, 100000 tons of positive electrode, 80000 tons of negative electrode and 80000 tons of electrolyte are promoted in 2025-2027, and the industrial scale exceeds 350 million yuan.

How to completely separate active materials from copper and aluminum foils in the waste lithium ion battery in an environment-friendly manner, efficiently recover nickel, cobalt, manganese and lithium metal elements in the waste lithium ion battery, and simultaneously realize efficient recycling of electrolyte and organic substances in the pretreatment and crushing process of the waste lithium ion battery, thereby really realizing win-win of environmental protection and economic development, leading the lithium ion battery industry to obtain benign sustainable development and becoming the key point and difficulty of waste lithium ion battery recovery. At present, the research on recycling of waste lithium ion batteries mainly focuses on the aspect of recycling of subsequent valuable metals of the waste lithium batteries, but the research on recycling of electrolyte and organic matters in the pretreatment process of the waste lithium batteries is less, and the problems of fluorine pollution and organic matter pollution caused by the electrolyte during large-scale production are solved. Therefore, the resource recycling of the waste lithium batteries is accelerated, and particularly the environmental protection recycling of the electrolyte in the pretreatment process is particularly critical.

In the recovery technology of waste lithium ion batteries, the recovery treatment of electrolyte is mainly related, and generally methods such as high-temperature calcination, spraying, alkali adsorption and the like are adopted. Known patents include chinese patents CN201511029669.4, CN201610872053.1 and CN 201410116605.7.

Chinese patent CN201511029669.4 discloses a method, which comprises disassembling the waste lithium ion battery after fully discharging, and removing the casing, positive and negative terminals, sealing ring and cover plate; transferring all the electrolyte, the current collectors with the anode and cathode materials and the diaphragm into a supercritical extraction device; adjusting the temperature, pressure, extraction time and flow of the supercritical carbon dioxide fluid, and then extracting the organic solvent and the additive; and (3) analyzing the components of the obtained solvent, supplementing electrolyte salt, organic solvent and additives according to the analysis result, and adjusting the mixture ratio to prepare electrolytes with different functions. The method has harsh operating conditions and is difficult to realize large-scale industrial application.

Chinese patent CN201610872053.1 discloses a method, which comprises the following steps: the lower part is equipped with waste gas entry, the top is equipped with waste gas outlet's alkali lye spray column and the condenser that links to each other with waste gas outlet, and waste gas entry linkage is used for separating the cyclone of gas-solid phase in the organic gas, and the condenser passes through active carbon storage tank I and the active carbon storage tank II that the pipe connection is used for adsorbing waste gas, connects gradually filter, vacuum pump and gas-water separation tank through the pipeline after active carbon storage tank I and active carbon storage tank II are parallelly connected, the gas-water separation tank with the condenser links to each other, and the processing method of waste gas, including gas dust removal, alkali lye spray washing, gas condensation, pressure swing. The method carries out activated carbon absorption on the volatile fluorine-containing organic waste gas in the crushing process, and the method adopting activated carbon adsorption can not realize the efficient recycling of the electrolyte and the standard-reaching emission of the waste gas.

Chinese patent CN201410116605.7 discloses a method which comprises the following steps of a, discharging waste lithium ion batteries, b, crushing the waste lithium ion batteries into sheets with the diameter of 10 ~ 20mm in a closed shear type crusher, spraying when crushing, dissolving lithium hexafluorophosphate in the waste lithium ion batteries into spraying liquid, c, stripping carbon powder on the surface of a copper foil through stirring, dissolving electrolyte into the spraying liquid, then recovering the carbon powder, d, sending the sheet objects into a sodium hydroxide solution, stripping lithium cobaltate powder on the surface of an aluminum foil through stirring, then recovering the lithium cobaltate powder, e, cleaning the sheet objects, recovering the lithium cobaltate powder, f, separating and recovering plastic and copper-aluminum mixtures.

Disclosure of Invention

Aiming at the defects of the method, the invention provides a method for effectively solving the problems, namely separating and recovering the electrolyte in the waste lithium battery by using an ultrasonic enhanced extraction method. The method has the advantages of wide application range and high recovery rate of the electrolyte and the electrode powder, realizes high-efficiency separation and recovery of the electrolyte and the electrode powder in the waste lithium ion battery in the crushing process by an ultrasonic enhanced extraction method, and simultaneously, the main extractant and the auxiliary extractant can be recycled, thereby conforming to the green development concept of the waste battery recovery industry. The concrete contents are as follows: (1) the method comprises the following steps of protecting waste batteries with inert gas and breaking the waste batteries in a closed atmosphere in an electrified manner: and disassembling and crushing the waste lithium battery under the protection of inert gas in a closed state to obtain the crushed waste battery. (2) The method comprises the following steps of (1) recovering electrolyte in waste battery scraps through ultrasonic enhanced extraction: and putting the waste lithium battery crushed aggregates into extraction equipment, and performing extraction and separation on the electrolyte. (3) Evaporating, condensing, separating and recycling the extracted solution: and evaporating and condensing the extracted solution to respectively obtain electrolyte, a main extracting agent and an auxiliary extracting agent, and recycling the main extracting agent and the auxiliary extracting agent to the extraction process. Wherein the main extractant is ethyl propionate and ethylene carbonate, and the auxiliary extractant is N-methyl pyrrolidone

The waste lithium battery comprises: lithium ion batteries such as nickel-cobalt-manganese ternary lithium batteries, nickel-cobalt-aluminum lithium batteries, cobalt acid lithium batteries, lithium manganate batteries, lithium iron phosphate batteries and the like also have no special requirements on the shapes of the batteries. Crushing and sorting the extracted battery crushed aggregates again: and crushing the obtained battery crushed aggregates again, sorting by airflow and sorting by magnetic force to obtain electrode powder, a diaphragm and copper-aluminum particles.

Compared with the prior art, the invention has the beneficial effects that:

1. the invention has wide application range, realizes the high-efficiency separation and recovery of the electrolyte in the waste lithium ion battery in the crushing process by an ultrasonic enhanced extraction method, and simultaneously, the main extractant and the auxiliary extractant can be recycled, thereby conforming to the green development concept of the waste battery recovery industry. In the whole pretreatment and extraction process, the recovery rates of the electrolyte, the main extractant and the auxiliary extractant respectively reach more than 90 percent, and continuous, stable and large-scale industrial production can be realized.

2. The electrolyte in the waste lithium battery is extracted and recycled by using an ultrasonic enhanced extraction method, and no wastewater, waste gas or waste residue is generated in the whole treatment process. The method fundamentally solves the problem of environmental pollution caused by electrolyte volatilization in the pretreatment process of the waste lithium battery, really realizes zero discharge of three wastes, and has good economic and social benefits.

Drawings

FIG. 1 is a block diagram of the process flow of the present invention.

Detailed Description