Fractionation of the organic matter contained in leachate resulting from two modes of landfilling: An indicator of waste degradation

Waste degradation and leachate quality on composting platform: A case study in Lome, Togo

“…At the end of degradation period, they accounted for 10% of the organic matter. This value is in accordance with a leachate resulting from a stabilized waste (Berthe, 2008). However, the potentially induced biogas substances (Fricke et al, 2005), like the HPI* and the TPH* represented 52.5% of the organic matter.…”

“…SUVA index increased significantly (p<0.05) at each step of composting showing that the molecules polymerized as function of time, confirming the results, of a SUVA index > 20 for a stabilized leachate (François et al, 2006;Berthe et al, 2008). This evolution of the SUVA advocates firmly the transformation of HPI* fractions to more humified molecules like the HPO* and the AH*.…”

“…After 100 days of composting the concentrations of these acids became lower causing a slowdown in the acidity till the end. Similar observations were seen during the anaerobic storage of landfills waste, where the waste degradation leads to the production of a leachate pH less than 6, and then evolves to 7.5 after 5 years before reaching 8 after 10 years, the latter value meaning that the leachate is stable (Renou et al, 2008;Berthe et al, 2008). Thus, it was concluded that the acidity of the leachate depends on the degradation of windrow from which it originates.…”

“…An improvement has been noted when compared to the material balance where a value of 65% has been obtained but the resulted composts cannot be regarded as stable, taking into consideration the levels of these parameters (Croué et al, 1993). In fact, when (AH*+HPO*) > 50% and HPI* < 30%, the leachate is said to be stabilized (Berthe et al, 2008). In this study, the proportions of (AH * + HPO *) and HPI * are respectively 47.1 ±0.2% and 29.83±0.06% after 124 days.…”

“…From C2 (1883±284 mgO 2 /L), the COD was stabilized, the residual organic matter less susceptible to degradation and then the COD stabilzed until the compost is harvested. The COD value (< 4000 mg O 2 /L) of the leachate after 124 days points to a stabilized leachate (Renou et al, 2008;Berthe et al, 2008).…”