Field Experiment on Remediation of Municipal Solid Waste Dumping Site by Combining Air Injection and Leachate Recirculation

摘要

Municipal solid waste (MSW) dumping sites have attracted much attentionrecently due to the increasing demand for land brought on by urban construction inChina. In this study, a three-month field experiment on the effects of combining airinjection and leachate recirculation was analyzed based on the indicators examined, suchas solid waste moisture content (MC), volatile solid (VS), and dissolved total organiccarbon (DTOC) of the leaching solution, as well as chemical oxygen demand (COD),biochemical oxygen demand (BOD), and NH4-N of the leachate. Results show that58.9% of VS and 97.5% of DTOC were reduced during the experimental period. The pHlevel of the leachate was always basic (pH > 7.4), indicating that volatile fat acids(VFAs) did not accumulate. COD content of the leachate remained at a lowconcentration range of 1200-1500 mg/L. The BOD/COD ratio of the leachate was lowand the biodegradability of leachate worsened. The VS/FS ranged from 0.16-0.21. Thequick decrease in release intensity of pollutants in the leachate illustrated theacceleration of stabilization of the dumped MSW through the combination of forcedaeration and leachate recirculation.