Soil plastics have emerged as a critical environmental issue due to their negative impact on soils and crops, making their monitoring essential for evaluating the environmental impacts of plastics. However, no standardized method for analyzing soil plastics has been established yet. Most studies employ chemical digestion to remove organic matter and density separation to extract plastics from soil particles. However, the density separation is labor-intensive, time-consuming, and incurs high costs. Moreover, it is not well-suited for handling large sample volumes, posing limitations on accurately analyzing the actual amount of soil plastics that the entire soil sample represents. To overcome these limitations, we developed a soil-plastic separation system utilizing microbubbles. This system aims to enhance the efficiency of soil plastic analysis by reducing processing time and securing high recovery rates. The separation system demonstrated comparable recovery rates to the density separation method, achieving over 90.44 ± 1.59% for polyethylene (PE) fibers across three different soil types and standard sand samples. Additionally, excluding the chemical digestion, the separation system significantly reduced processing time per batch to approximately 12 hours. The developed system can be easily applied to domestic soil environments and can be utilized as an efficient and sustainable processing method for soil plastic monitoring.

Keywords: Plastic waste, Soil plastic monitoring, Agricultural soil, Sustainable waste management, Microbubble