Complete Treatment of Compost Leachate U

A lab-scale sequencing batch reactor (SBR) equipped with a flat sheet membrane in submerged configuration, referred to as MSBR, was employed to treat composting leachate. The system was fed with biologically treated leachate characterized by Chemical Oxygen Demand (COD) levels ranging from 70 to 1360 mg/L. Important parameters such as pH, Electrical Conductivity (EC), and Dissolved Oxygen (DO) were routinely monitored. The analysis of total COD, Soluble COD (SCOD), Biological Oxygen Demand (BODs), Total Suspended Solids (TSS), and Volatile Suspended Solids (VSS) were performed in both the feed and filtrate at steady state, twice a week for a duration of six months. It was observed that the BODs concentration consistently remained below the standard limits. The removal efficiency of total COD in the bioreactor improved over time, reaching up to 80%. Despite significant fluctuations in influent SCOD (varying from 50 to 1050 mg/L), the effluent SCOD remained stable. Furthermore, about 60% of the feed SCOD was identified as non-biodegradable material, which was effectively separated by the membrane. Notably, the micro pore membrane achieved a removal rate of up to 99% for additional solids, primarily of colloidal nature. The leachate sample exhibited an EC range of 0.86 to 4 mS/cm at 22 °C, which significantly decreased post membrane filtration. The findings indicate that MSBR is a versatile technology capable of treating composting leachate to meet regulatory standards when employed appropriately.