Release of Humic Substances during In Situ Aeration

摘要

In situ aeration is a promising remediation technology for old landfills, as it couldaccelerate carbon transformation, reduce organic load, decrease landfill post closureperiod and achieve earlier beneficial reuse of land. In this experiment, three landfillaeration simulators were constructed, utilizing heat belt to achieve incubationtemperature at 35°C, 45°C and 55°C respectively. During the past 291 days, leachateCOD in the aeration reactors were 1～5 times higher than that in anaerobic reactors.Analysis of the dissolved organic carbon (DOC) showed that aeration increased theconcentration of organic acid, especially humic acid. Further structural characterizationof the extracted humic matters will be conducted in elemental composition, Fouriertransform infrared spectroscopy (FTIR), and Carbon-13 Nuclear Magnetic Resonance(~(13)C-NMR). The results of characterization work could help to explain the cause ofincreased organic load by aeration, and better understand the different chemical andbiological mechanism involved in different aeration modes.