基于LCA的废锂电池典型回收再生工艺碳足迹分析和环境影响评价

CARBON FOOTPRINT ANALYSIS AND ENVIRONMENTAL IMPACT ASSESSMENT OF TYPICAL RECYCLING PROCESSES OF SPENT LITHIUM BATTERIES BASED ON LCA

在“双碳”目标下,废锂电池回收可通过资源循环利用实现减污降碳并缓解金属资源供应紧张,是国家重要的战略研究方向。目前国内主要采用湿法回收工艺进行废锂电池正极材料回收,但工艺流程长导致不同工艺环节的物碳足迹和三废产生尚不清晰。针对废锂电池回收再生NCM811三元前驱体典型湿法冶金工艺,从减污降碳的视角,对全流程各环节进行了生命周期综合评价分析。通过建立回收再生工艺中不同单元节点的投入产出模型,采用IPCC 2013 GWP100a方法计算回收再生1000 kg高镍三元前驱体产品的碳足迹为2.07×10^(4)kg CO_(2)eq,并使用Eco-indicator 99方法对各工艺单元进行环境影响评价,结果表明:预处理、前驱体合成、除杂节点碳足迹分别贡献42.99%、23.46%、21.66%,环境生态指数依次为582.88,380.94,394.06 Pt,明确了预处理、前驱体合成、除杂单元是应重点关注的减污降碳环节。

Under the"carbon peaking and carbon neutrality"goal,the recycling of waste lithium batteries can achieve pollution reduction and carbon reduction through resource recycling,and alleviate the tight supply of metal resources.It is an important strategic research direction of the country.Currently,hydrometallurgical recovery processes are mainly used in China to recover waste lithium battery cathode materials,but the long process flow leads to unclear material and carbon footprints and three wastes generation in different processes.This study focuses on the typical hydrometallurgical process of recycling and regenerating NCM811 ternary precursor from waste lithium batteries,and conducts a comprehensive life cycle assessment and analysis of each link of the entire process from the perspective of pollution reduction and carbon reduction.By establishing input-output models for different unit nodes in the recovery and regeneration process,then use the IPCC 2013 GWP 100a method to calculate the carbon footprint of regenerate 1000kg of rich-nickel ternary precursor products as 2.07×10^(4)kg CO_(2)eq and the Eco-indicator 99 method was used to conduct environmental impact assessment on each process unit.The results showed that the carbon footprint of pretreatment,precursor synthesis,and removing nodes respectively contributed 42.99%,23.46%,and 21.66%,and the environmental ecological index was 582.88Pt,380.94Pt,and 394.06Pt,respectively.It was clear that pretreatment,precursor synthesis,and removing units should be focused on pollution reduction and carbon reduction.