title: Kinetics of organic matter removal and humification progress during sewage sludge composting.
abstract: This study investigated the kinetics of organic matter (OM) removal and humification during composting of sewage sludge and lignocellulosic waste (wood chips, wheat straw, leaves) in an aerated bioreactor. Both OM degradation and humification (humic substances, HS, and humic acids, HA formation) proceeded according to 1. order kinetics. The rate constant of OM degradation was 0.196 d(-1), and the rate of OM degradation was 39.4 mg/g OM d. The kinetic constants of HS and HA formation were 0.044 d(-1) and 0.045 d(-1), whereas the rates of HS and HA formation were 3.46 mg C/g OM d and 3.24 mg C/g OM d, respectively. The concentration profiles of HS and HA indicated that humification occurred most intensively during the first 3 months of composting. The high content of HS (182 mg C/g OM) in the final product indicated that the compost could be used in soil remediation as a source of HS for treating soils highly contaminated with heavy metals.
authors.affiliation: University of Warmia and Mazury in Olsztyn, Department of Environmental Biotechnology, Słoneczna St. 45G, 10-709 Olsztyn, Poland. Electronic address: dorotak@uwm.edu.pl.
authors.forename: Dorota
authors.initials: D
authors.lastname: Kulikowska
mesh_terms: D019149:Bioreactors; D006812:Humic Substances / Q000032:analysis*; D007700:Kinetics; D012722:Sewage / Q000737:chemistry*; D014865:Waste Disposal, Fluid
chemical_list: D006812:Humic Substances; D012722:Sewage
keywords: Composting; Humic acids; Humic substances; Kinetic constants; Organics; Sewage sludge