Effects of Phosphate Ion Concentration on Wastewater Treatment by Ferrite Processt

Abstract

The saturated magnetization (σ) of the ferrite sludge formed by ferrite process treatment of wastewater containing heavy metal and phosphate ions was measured over a wide range of dilution ratio of wastewater (f) (ex. when the heavy metal or phosphate ion concentration of the wastewater reduced to 1/10 of the original one, f=10) and the effects of phosphate ion concentration on the wastewater treatment by ferrite process were discussed quantitatively. Theσ -f curves for various heavy metal and phosphate are similar to each other (Figs.1and 4), are located in variousf regions and depend on the kind of heavy metal and phosphate ions (Figs.2, 3 and 5, and Table 1). The curves have the slopes of 1.0 in low f region and 2.6 in middle f region, and the values of a approach asymptotically to 92 emu/g of Fe₃0₄with increasingf. The rapid decrease ofσ with decreasing f may have resulted from the formation of iron phosphates and/or by-products in ferrite process. The ferrite process requires the value of σ above 60 emu/g for good magnetic separation, steady operation of the process, industrial applications of the sludge and good quality of the treated water (Fig.1). t Treatment of Wastewater Containing Heavy Metal Ion by Ferrite Process. II.