The emission of volatile compounds during the aerobic and the combined anaerobic/aerobic composting of biowaste

Emission of oxygenated volatile organic compounds (OVOCs) during the aerobic decomposition of orange wastes

“…This profile of emitted OVOCs was consistent with that of OVOCs in citrus fruit flesh (Umano et al, 2002) or juice (Buettner and Schieberle, 2001;Brat et al, 2003), with ethanol, acetaldehyde, and ethyl acetate being the predominant compounds extracted. Also, the results in the study were quite similar to previous studies, which revealed that ethanol, ethyl acetate, 2-butanone and acetaldehyde typically showed high levels in odor sources such as municipal solid wastes (Staley et al, 2006) and waste treatment facilities (Eitzer, 1995;Smet et al, 1999;Dorado et al, 2014;Lehtinen et al, 2013). As shown by Fig.…”

“…2), just as those detected in citrus fruit flesh (Umano et al, 2002) and juice (Buettner and Schieberle, 2001;Brat et al, 2003) and in intermediates of aerobic metabolism of organic materials (Eitzer, 1995;Staley et al, 2006). Alcohols were also observed as major VOCs emitted from green wastes (lawn clippings, yard prunings, and food wastes, as well as green and woody wastes) (Kumar et al, 2011) and biowastes (70% garden waste, 20% kitchen waste and 10% nonrecyclable paper) (Smet et al, 1999) during the aerobic composting process. Ethanol was found to be the most abundant species among the OVOCs released, followed by methanol, ethyl acetate, methyl acetate, 2-butanone and acetaldehyde.…”

“…These results indicated that OVOCs were mainly released at the early stage of orange waste decomposition, which was consistent with previous studies. Knox (1990) observed that the levels of alcohols were greatest in fresh refuse, and other studies also found that OVOCs (alcohols, carbonyl compounds, esters and ethers) were principally emitted at the early stage of waste decomposition (Smet et al, 1999;Muezzinoglu, 2003;Chiriac et al, 2011;Kumar et al, 2011;Delgado-Rodríguez et al, 2012) and bio-drying (He et al, 2010). Considering that organic waste is an important component of MSWs, and that municipal wastes may stay in dustbins or transfer into stations up to a week before reaching landfills or incinerators, and their decomposition largely takes place under aerobic conditions during the collection and distribution processes and the early times in landfills (Statheropoulos et al, 2005;Zhang et al, 2012), the results in the present study suggested that considerable amounts of OVOCs are emitted during early disposal of organic wastes and thus contribute to malodor from these waste treatment facilities.…”

“…Thus, OVOCs are also major non-methane organic compounds in waste gases from various waste treatment processes including transferring (Dorado et al, 2014), landfilling (Davoli et al, 2003;Dincer et al, 2006;Tassi et al, 2009) and composting (Eitzer, 1995;Smet et al, 1999;Pierucci et al, 2005;Romain et al, 2005;Staley et al, 2006;He et al, 2010;Kumar et al, 2011;Lehtinen et al, 2013). Emission of OVOCs from these treatment facilities may not only burst into their airborne ambient levels in the neighborhood (Davoli et al, 2003;Dincer et al, 2006) and contribute to ground-level ozone formation (Kumar et al, 2011), but also trigger complaints of sensory irritation by local residents.…”

“…Many previous studies have measured the composition and production of OVOCs from laboratory-controlled composting or pilot-scale landfill using different combinations of organic wastes (Smet et al, 1999;Staley et al, 2006;Kumar et al, 2011). OVOCs are present in fleshes and juices of fruits, particularly citrus (Umano et al, 2002;Brat et al, 2003).…”