Biodegradability of Municipal Organic Waste: A Respirometric Test
Biodégradabilité des biodéchets : étude respirométrique
Résumé
Home composting of the organic fraction of the municipal solid waste mainstream can help reduce the economic and environmental burden currently faced by urban centres. The physico-chemical properties of the organic fraction components, mainly food waste (FW) and yard trimmings (YT), govern the process effectiveness, namely its rate and extent. The objective of the study was to identify the most effective home composting formula using respirometric tests measuring oxygen uptake. Pure, binary and tertiary formulas of FW, YT and wood chips (WC) were aerated for 32 days in cells maintained at 40 C. Results indicated that the formula composition had a significant impact on the rate and cumulative O2 uptake (p\0.01). The binary formula of FW:YT with a wet volume fraction of 0.5:0.5 produced the highest peak O2 uptake rate (OUR) and cumulative oxygen uptake (COU) of 145 mol/h/kg dm and 28.4 mol/kg dm, respectively, followed by the tertiary formula of FW:YT:WC with a fraction of 0.33:0.33:0.33, at 115.6 mol/h/kg dm and 15.3 mol/kg dm. Considering peak OUR and COU, the binary formula of FW and YT is thus most effective in supporting an active microbial activity for a fast composting process and the generation of high temperatures. Accordingly, adding WC as bulking agent is not necessary.