Anaerobic treatment of fresh leachate from a municipal solid waste incinerator by upflow blanket filter reactor

Abstract

This paper describes the feasibility of fresh leachate treatment by an upflow blanket filter (UBF). Through dilution and partial effluent recycling, the organic loading rates increased from 0.51 to 14.56 kg COD/(m 3 $d), meanwhile the corresponding hydraulic retention time decreased from 9.0 to 3.6 d. The reactor was able to achieve steady-state within 80 d. Based on the distribution of COD fluxes in the process, it was concluded that anabolism was the main pathway of COD removal in the initial phase (1-33 d), accounting for 57%-85% of total COD removed. As the anaerobic consortium of bacteria reached steady-state (after 70-86 d), the majority of COD removed was transformed into methane, because the specific methane yield was close to the theoretical value (0.36 L CH 4 /(g COD deg )).

Tertiary treatment of biologically pre-treated landfill leachates by non-catalytic wet oxidation

“…Due to their cost-effectiveness, biological processes are the methods most commonly adopted to remove the bulk of organic pollutants from landfill leachate. Nevertheless, although biological processes are quite effective when they are applied to relatively young leachates, they are less efficient for the treatment of the older ones with higher content in refractory compounds and ammonium [7,8]. The landfill leachate investigated in this study had already been treated biologically; however, it still had high chemical oxygen demand (COD), together with very low biodegradability and an intense dark colour.…”