Sjölunda Wastewater Treatment Plant, Malmö At the Sjölunda plant in Malmö wastewater from 550,000 inhabitants is treated. The plant was built in 1963. Recently expansion of biological treatment has reduced the use of precipitation chemicals to meet the Swedish requirements and the plant has at the same time reached emission requirements of organic compounds, phosphorous, and nitrogen. The sludge produced is used at the plant’s own production unit for biogas.