title: Load and distribution of organic matter and nutrients in a separated household wastewater stream.
abstract: Wastewater from a source-separated sanitation system connected to 24 residential flats was analysed for the content of organic matter and nutrients and other key parameters for microbiological processes used in the treatment and reuse of wastewater. Black water (BW) was the major contributor to the total load of organic matter and nutrients in the wastewater, accounting for 69% of chemical oxygen demand (COD), 83% of total nitrogen (N) and 87% of phosphorus (P). With a low COD/N ratio and high content of free ammonia, treating BW alone is a challenge in traditional biological nitrogen removal approaches. However, its high nitrogen concentration (1.4-1.7 g L(-1)) open up for nutrient reuse as well as for novel, more energy efficient N-removal technologies. Grey water (GW) contained low amounts of nutrients relative to organic matter, and this may limit biological treatment processes under certain conditions. GW contains a higher proportion of soluble, readily degradable organic substances compared with BW, which facilitates simple, decentralized treatment approaches. The concentration of organic matter and nutrients varied considerably between our study and other studies, which could be related to different toilet flushing volumes and water use habits. The daily load per capita, on the other hand, was found to be in line with most of the reported studies.
authors.affiliation: a Department of Environmental Sciences , Norwegian University of Life Sciences , Postboks 5003 N-1432 , Aas , Norway.
authors.forename: Daniel
authors.initials: D
authors.lastname: Todt
authors.forename: Arve
authors.initials: A
authors.lastname: Heistad
authors.forename: Petter D
authors.initials: PD
authors.lastname: Jenssen
mesh_terms: D003247:Conservation of Natural Resources; D009584:Nitrogen / Q000032:analysis*; D009930:Organic Chemicals / Q000032:analysis*; D010758:Phosphorus / Q000032:analysis*; D062065:Wastewater / Q000737:chemistry*
chemical_list: D009584:Nitrogen; D009930:Organic Chemicals; D010758:Phosphorus; D062065:Wastewater
keywords: black water; grey water; nutrient load; organic load; source-separating sanitation