title: On site experiments of the slanted soil treatment systems for domestic gray water.
abstract: In order to make a breakthrough for the acute problem of water shortage in the world, the key words "decentralization and re-use" are very important for new sustainable sanitation systems that will be developed. Therefore, we focused on a new treatments system called "a slanted soil treatment system" which combines a biotoilet system with a domestic grey water treatment system. Because this system is a low cost and compact system, the system can be easily introduced to homes in urban areas or in the suburbs of cities in many developing countries. In this study, we performed on site experiments carried out on Shikoku Island, Japan, for several years. We obtained the following results. The slanted soil treatment system could remove organic pollutants and total nitrogen and total phosphorus in grey water effectively. Furthermore, the system performance became high in the case of the high concentration of the influent water. The nitrification reaction and denitrification reaction were speculated to exist due to aerobic zones and anaerobic zones present in the slanted soil treatment system. The slanted soil treatment system could perform for approximately 3 years with zero maintenance. The plug flow model of 1st order reaction kinetics could describe the reaction in the slanted soil treatment system. However, it is necessary to improve the system to maintain the performance in all seasons.
authors.affiliation: Bio&Eco Engineering Research lab, National Institute for Environmental Studies, Ibaraki, Japan. itayama@nies.go.jp
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Itayama
authors.forename: Masato
authors.initials: M
authors.lastname: Kiji
authors.forename: Aya
authors.initials: A
authors.lastname: Suetsugu
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Tanaka
authors.forename: Takeshi
authors.initials: T
authors.lastname: Saito
authors.forename: Norio
authors.initials: N
authors.lastname: Iwami
authors.forename: Motoyuki
authors.initials: M
authors.lastname: Mizuochi
authors.forename: Yuhei
authors.initials: Y
authors.lastname: Inamori
mesh_terms: D001673:Biodegradation, Environmental; D003247:Conservation of Natural Resources; D007564:Japan; D012987:Soil; D013383:Suburban Population; D014038:Toilet Facilities; D014507:Urbanization; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification / Q000379:methods* / Q000592:standards
chemical_list: D012987:Soil; D014874:Water Pollutants, Chemical