摘要：The effect of aggregation precipitation on the removal of phosphorus from chemically waste water was investigated. Concentrations of total phosphorus in untreated and treated water discharged from chemical laboratories were determined sixty times from April, 1985, to December, 1985. The average concentrations of total phosphorus in the untreated and treated water were 0.63 and 0.11 mg/l, respectively. The data showed that 76.2% of total phosphorus (average) was eliminated by the aggregation precipitation. In order to clarify the mechanism of removal, the sludge produced by the treating plant was fractionated into easily water-soluble, ferrous salt including aluminum, calcium salt and insoluble fractions. When the contents of total phosphorus in the respective fractions were determined and it was found that about 70% of the total phosphorus was associated with calcium salt fraction. The data suggested that significant amounts of total phosphorus was removed by reaction with calcium hydroxide added during the aggregation precipitation process.
