title: Modeling organic micro pollutant degradation kinetics during sewage sludge composting.
abstract: Degradation of 13 different organic micro-pollutants in sewage sludge during aerobic composting at 5 different temperatures over a 52 day period was investigated. Adequacy of two kinetic models: a single first order, and a dual first order expression (using an early (first 7 days) and a late-time (last 45 days) degradation coefficient), for describing micro-pollutant degradation, and kinetic constant dependency on composting temperature were evaluated. The results showed that both models provide relatively good descriptions of the degradation process, with the dual first order model being most accurate. The single first order degradation coefficient was 0.025 d(-1) on average across all compounds and temperatures. At early times, degradation was about three times faster than at later times. Average values of the early and late time degradation coefficients for the dual first order model were 0.066 d(-1) and 0.022 d(-1), respectively. On average 30% of the initial micro-pollutant mass present in the compost was degraded rapidly during the early stages of the composting process. Single first order and late time dual first order kinetic constants were strongly dependent on composting temperature with maximum values at temperatures of 35-65°C. In contrast the early time degradation coefficients were relatively independent of composting temperature.
authors.affiliation: Department of Chemistry, Biotechnology and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 57, 9000 Aalborg, Denmark; Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark; College of Earth & Environmental Sciences, University of the Punjab, 54000 Lahore, Pakistan; Department of Civil Engineering, Xi'an Jiaotong-Liverpool University, Suzhou 215123, China.
authors.forename: Yumna
authors.initials: Y
authors.lastname: Sadef
authors.affiliation: Department of Chemistry, Biotechnology and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 57, 9000 Aalborg, Denmark; Department of Civil Engineering, Xi'an Jiaotong-Liverpool University, Suzhou 215123, China.
authors.forename: Tjalfe Gorm
authors.initials: TG
authors.lastname: Poulsen
authors.affiliation: Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark.
authors.forename: Kai
authors.initials: K
authors.lastname: Bester
mesh_terms: D000332:Aerobiosis; D001673:Biodegradation, Environmental; D007700:Kinetics; D008962:Models, Theoretical; D012037:Refuse Disposal / Q000379:methods*; D012722:Sewage / Q000032:analysis; D012989:Soil Pollutants / Q000378:metabolism*; D013696:Temperature
chemical_list: D012722:Sewage; D012989:Soil Pollutants
keywords: Aerobic composting; Composting temperature; Kinetic models; Organic micro-pollutant degradation