The production, use and quality of sewage sludge in Denmark.
In Denmark, the production of municipal sewage sludge decreased from approximately 170,000 ton d.m. in 1994 to 140,000 ton d.m. in 2002. The sludge is handled and treated in a number of ways. The quality of Danish sludge has steadily improved since the middle of the 1980s, when the first set of quality criteria for heavy metals was introduced. In 1997, cut-off criteria for the organic pollutants, LAS, DEHP, nonylphenol and PAHs were introduced. Effective control from authorities, voluntary phasing out agreements with industry, improved source identification tools, better handling and after-care methods have in combination with higher waste duties led to a significant reduction in the sludge level of especially cadmium, mercury, chromium, LAS and nonylphenol. The increased quality demand has, nevertheless, also led to a minor reduction in the use of sewage sludge as organic fertiliser on agricultural land.
Jensen
John
J
National Environmental Research Institute, P.O. Box 314, Vejlsøvej 25, DK-8600 Silkeborg, Denmark. john.jensen@dmu.dk
Jepsen
Svend-Erik
SE
D000383:Agriculture; D003247:Conservation of Natural Resources; D003718:Denmark; D005308:Fertilizers; D019216:Metals, Heavy / Q000032:analysis; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis; D012722:Sewage / Q000737:chemistry*; D014873:Water Pollutants / Q000032:analysis*
D005308:Fertilizers; D019216:Metals, Heavy; D011084:Polycyclic Aromatic Hydrocarbons; D012722:Sewage; D014873:Water Pollutants