Landfill leachate treatment using the sequencing batch biofilm reactor method integrated with the electro-Fenton process

A study was conducted on the treatment of landfill leachate by combining the sequencing batch biofilm reactor (SBBR) method with the electro-Fenton method. The reduction of chemical oxygen demand (COD), biological oxygen demand (BOD5), and ammonia nitrogen (NH4+-N) from the leachate by the SBBR method was investigated. For the electro-Fenton experiment, the changes in COD and total organic carbon (TOC) with the increase in H2O2 dosage and electrolysis time under optimal conditions were also analysed. The results showed that the average efficiencies of reduction of COD, BOD5, and NH4+ -N achieved using the SBBR method were 21.6 %, 54.7 %, and 56.1 %, respectively. The bio-effluent was degraded by the subsequent electro-Fenton process, which was rapid over the first 30 min then subsequently slowed. After 60 min of the electro-Fenton treatment, the efficiencies of reduction of TOC, COD, and BOD5 were 40.5 %, 71.6 %, and 61.0 %, respectively. There is a good correlation between the absorbance of leachate at 254 nm (UV254) and COD or TOC during the electro-Fenton treatment.