| 摘要 |
<p>[0068] Phosphate-contaminated water passes through a domestic sewage treatment system, in which oxidation of the ammonium progresses far enough t o cause a lowering of the pH to 5 or less. The water is passed over sand grain s coated with aluminum hydroxide (gibbsite). Enough Al3+ ions enter solution, at the low pH, to cause all the phosphate-P to precipitate as aluminum phosphate, a nd nothing else precipitates other than the aluminum phosphate.</p> |
