Treatment method of waste lithium iron phosphate

Abstract

The invention discloses a treatment method of waste lithium iron phosphate. The method comprises the following steps of: pretreating a waste lithium iron phosphate material, adding the pretreated material into a phosphoric acid solution, performing reacting and then filtering to obtain a first filtrate and a first filter residue; adding sulfide into the first filtrate for reaction, and then performing filtering to obtain a second filtrate and a second filter residue; adding iron powder into the second filtrate, performing stirring to react, removing iron, adding battery-grade lithium carbonateinto the obtained iron-removed material, and performing stirring to react until no bubbles are generated so as to obtain a reaction material; adding the reaction material into a water-soluble organiccarbon source, performing stirring, dispersing and dissolving, and performing spray drying on the obtained material in a spray dryer to obtain a dried material; and putting the dried material into aroller way furnace, performing calcining, crushing, mixing and screening, removing iron, and carrying out vacuum packaging. According to the method, resource utilization of the waste lithium iron phosphate can be achieved, high-end circulation is achieved, the recovery rate of all elements is high, the waste water generation amount is small, and the obtained lithium iron phosphate is excellent inperformance.

Description

technical field [0001] The invention relates to a treatment method for waste lithium iron phosphate, belonging to the technical field of waste treatment. Background technique [0002] With the adjustment of new energy policies, the subsidy has gradually declined. At the same time, the price of lithium iron phosphate has also dropped from the previous 100,000 / ton to the current 45,000 / ton, and its application field has gradually expanded. From the previous bus Vehicles are extended to special purpose vehicles, low-speed electric vehicles and electric vehicles below A0 level. [0003] Recently, the Ministry of Industry and Information Technology released the fourth batch of "Catalogue of Recommended Models for the Promotion and Application of New Energy Vehicles" in 2019. A total of 238 models were on the list, among which the models supporting lithium iron phosphate came from JAC , BAIC New Energy, Zotye Automobile , Chery Commercial Vehicles, Chufeng Automobile, FAW Jiefa...

AI Technical Summary

Problems solved by technology

[0013] The total amount of waste lithium iron phosphate obtained can reach more than 5,000 tons per year. How to deal with these waste lithium iron phosphate materials has become an important issue, such as using newly produced lithium iron phosphate materials in proportion to these waste materials. Although the way of use is simple to handle, there are very big hidden dangers, such as the magnetic material in it, how to handle it improperly may cause the safety performance of lithium iron phosphate battery to decrease, and at the same time have a great impact on the service life of lithium iron phosphate

[0014] Other treatment methods also have disadvantages such as long process, low added value of the obtained product, and large amount of sewage treatment.

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