Complicated pollution characteristics (particulate matter, heavy metals, microplastics, VOCs) of spent lithium-ion battery recycling at an industrial level

Abstract

The recycling of spent lithium-ion batteries has become a common concern of the whole society, with a large number of studies on recycling management and recycling technology, but there is relatively little study on the pollution release during the recycling process. Pollution will restrict the healthy development of the recycling industry, which makes relevant research very significant. This paper monitored and analyzed the battery recycling pretreatment process in a formal factory, and studied the pollution characteristics of particulate matter, heavy metals, and microplastics under different treatment stages. In addition, the release characteristics of VOCs during pyrolysis were also studied. When the green pretreatment process was used, PM₁₀ concentration in most processing units was below 100 μg/m³, indicating that the overall pollution prevention and control effect in the workshop is well-done. Particulate matter in workshop contained a large amount of metal components, mainly Fe, Cu, Co, Mn, Ni, etc. Microplastics were widely distributed in ground dust, and small-size microplastics are suspended in the air for a long time because of Brownian motion. Collecting ground dust and particulate matters is beneficial for controlling the emission of microplastics. During thermal treatment, Ethylene carbonate and dimethyl carbonate in the electrolyte would enter the atmosphere, and a large amount of short chain hydrocarbons released together, forming VOCs pollution. This study summarized distribution characteristics of different pollutants in a battery recycling factory. The basic pollution data provided are beneficial for improving the recycling technology of spent lithium-ion battery.