Degradation Of Sulfadiazine From Piggery Biogas Slurry By Three-dimensional Bio-electro-Fenton System

Piggry biogas slurry is the concentrated waste water remaining after anaerobic fermentation of pig manure.It’s high in COD and plant nutrients,and it can be used as a liquid fertilizer to return the entire amount to the area.Antibiotic residues in biogas slurry from pig farms,on the other hand,pose a significant environmental risk.Bioelectrofenton technology is a bioelectrochemical method for removing persistent organic pollutants with minimal energy use.The combination of the bio-electro-Fenton technique and a three-dimensional electrode improves bio-electro-Fenton technology’s ability to remove contaminants.To minimize antibiotic contamination and reduce the risk of returning biogas slurry to the field,the deployment of a three-dimensional bio-electro-Fenton system to remove antibiotics from piggry biogas slurry is critical.Sulfadiazien,which was found in high concentrations in piggry biogas slurry,was used as a representative antibiotic in this study,and a green three-dimensional bio-electro-Fenton system was set up by preparing a three-dimensional electrode to investigate the removal effect of Sulfadiazien in piggry biogas slurry.The specific research content is as follows:（1）The Fe in the 3D electrode is linked to the surface of the activated carbon electrode in the form of Fe₂O₃ micron particles,according to SEM data.Furthermore,the Fe/AC 3D electrode enhanced with iron has superior oxygen reduction reactivity and electrocatalytic performance than the standard AC 3D electrode,according to CV and LSV test findings.The electrical performance of the 3D BEF system based on Fe/AC electrode has also been demonstrated to be superior than the 2D BEF.When the external resistance is 1000,the 3D BEF system’s continuous power generation period is 1.5 times that of the two-dimensional system,and the three-dimensional BEF system’s maximum output voltage is 37.25%greater than the two-dimensional system’s.（2）When the p H of catholyte was 3,aeration intensity was 12 m L/min,and 130 m L 3D electrode was added,the three-dimensional BEF system achieved the best operation effect.Under the above conditions,the 3D BEF system had the best removal effect on sulfadiazine wastewater with a concentration of 10 mg/L,and the removal efficiency reached 97.79%after running for 60 min.Organic matter and ammonia nitrogen in piggery biogas slurry were not conducive to sulfadiazine removal by the system（3）The degradation mechanism and degradation path of sulfadiazine in three-dimensional BEF system were studied.In this system,the major mechanism of sulfadiazine degradation was·OH oxidative breakdown and direct electrolysis,followed by three-dimensional electrode adsorption and H₂O₂ weak oxidation.Six degradation intermediates were detected by HPLC-MS/MS,and three possible degradation pathways of sulfadiazine were deduced.（4）To carry out practical application,the three-dimensional BEF system was integrated with sewage treatment technology.Sulfadiazine in genuine piggery biogas slurry was handled with a three-dimensional BEF system and anaerobic biological treatment.The elimination efficiency of sulfadiazine from piggery biogas slurry was found to be 90.60%,which was 3.8times greater than that of a single anaerobic biological treatment procedure.The COD and NH₄⁺-N concentrations in biogas slurry meet the direct discharge threshold,lowering the risk of returning to the field.