化学沉淀-磁絮凝深度快速除磷的研究

采用化学沉淀法研究Al2（SO4）3、FeCl3、CaCl2的药剂用量和pH值对除磷效果的影响，探讨非磁性悬浮物磁性接种的机理，并分析了铝、铁、钙的磷酸盐沉淀物由于加入磁种而变得易于沉降，特别是在磁场力作用下沉降速度加快的原因。结果表明，Al2（SO4）3、FeCl3、CaCl2是磷酸根离子的有效沉淀剂，在适当的药剂投加量和pH值条件下，废水经过处理后，剩余磷的浓度小于0．5mg／L；生成的铝、铁、钙的磷酸盐沉淀物颗粒与Fe3O4颗粒在某一pH值下表面电性相反，易发生相互凝聚；磁性接种的铝、铁、钙的磷酸盐沉淀物不仅变得更重，而且在磁场中还受到与重力方向相同的磁场力作用。

Further and faster removal of phosphorus by chemical precipitation-magnetic fiocculation

The effects of Al2（SO4）3, FeCl3 and CaCl2 dosages and p H value of chemical precipitation on phosphorus removal are studied. The mechanism of magnetic seeding for nonmagnetic suspended substances is discussed by measuring the zeta potential of Fe3O4 and phosphates of aluminum, iron and calcium. It is found that the phosphates of aluminum, iron and calcium become more easily settled because of magnetic seeding, especially the action of magnetic field. It is also found that Al2 （SO4）3, FeCl3 and CaCl2 are efficient precipitators of phosphate ion, and the residual phosphorus content of treated wastewater is less than 0.5 mg/L under proper dosage and pH value. The granules of phosphates of aluminum, iron and calcium agglomerate easily with those of Fe3O4 because of their reverse surface potentials. The magnetic seeded precipitates of the phosphates not only become more weighty but also suffer from a magnetic force whose direction accords with the gravity.