Complementary treatment of leachate using sequencing batch reactor

Aims: The management of leachate has become to one of the main focuses for the environment management. The aim of this study was a complementary treatment of leachate using sequencing batch reactor (SBR). Materials and Methods: A bioreactor was fed by effluent with 70-1360 mg/L chemical oxygen demand (COD) concentration. The values of pH and dissolved oxygen (DO) were monitored routinely. However, analysis of 5-days biochemical oxygen demand (BOD 5 ), COD, and total suspended solid (TSS) was done in feed and effluent whenever the system reached steady state twice a week for 280 days. Results: The pH values in the influent were 7.4-8.16 that increased slightly up to 8 in the effluent. COD removal efficiency increased in bioreactor with time in all experiments up to 70%. The removal efficiency was 40-80% depending on the feeding values. TSS concentration in influent was ranged between 100 and 1860 mg/L that was decreased to 30-398 mg/L in the bioreactor effluent. In most cases, TSS values were below the standard limit. Conclusions: The acceptable performance of the SBR under different conditions suggests the promising capability of a full-scale, on-site SBR as efficient and versatile treatment system in handling the fluctuating nature of both the quantity and quality of composting leachate.