Remediation of atrazine-contaminated soil in a fluidized-bed DBD plasma reactor

In this study, an innovative approach combining dielectric barrier discharge (DBD) plasma and fluidized-bed techniques is proposed and employed to remediate atrazine (ATZ) contaminated soil. Compared with traditional fixed-bed plasma soil remediation system, the fluidized-bed DBD plasma soil remediation system ensures sufficient and uniform contact between the chemically reactive species and the fluidized soil particles, thereby improving the migration and infiltration of reactive species in the soil layer and achieving high-efficiency remediation of contaminated soil. The optimum removal efficiency of 91.2% and energy efficiency of 0.342 mg/kJ were achieved, respectively, after only 6 min fluidized-bed DBD plasma treatment, which were 35.5% and 38.9% higher than those in a fixed-bed DBD plasma system. The primary organic intermediates after fluidized-bed DBD plasma treatment were identified, and the toxicological evaluation of intermediates was performed. Additionally, possible degradation pathways of ATZ in the fluidized-bed DBD plasma reactor were proposed. This system may offer an ideal approach to facilitate mass transfer between chemically reactive species and contaminants on the surface of soil particles, which is expected to achieve efficient, rapid, and continuous treatment of actual contaminated soil.