Simultaneous Phosphate Precipitation and Particle Destabilization Using Aluminium Coagulants of Different Basicity

摘要: Chemical treatment of wastewater was investigated by conducting jar tests with a synthetic testwater. The influence different variables (pH, ortho-P concentration, particle hardness, humus concentration) on the competitive reactions aluminium coagulants and hydroxyl ions, respectively, studied under controlled conditions. data were evaluated assuming that basic phosphate A11.4PO4(OH)1.2, referred to as Alp A1(0H)3 are precipitated simultaneously. ratio A1P/A1T found depend initial pH, concentration coagulant’s basicity. In soft water matrix, amount coagulant not consumed P-precipitation about efficient for destabilization an equal in same, but free, raw water. hard matrices, however, enhance destabilization. Co-precipitation calcium even at pH = 6 identified main reason this effect. Humus concentrations order 5–10 mg/l can considerably increase demand A procedure advanced characterization evaluation respect chemical is suggested.