Phosphorus Removal in Biological Aerated Filters by Chemically Enhanced
Phosphorus removal by biological aerated filter(BAF) is ineffective, its effluent TP is much more than 0.5mg/L, so chemically enhanced phosphorus removal is neccessary. To solve this problem, domestic wastewater through BAF by adding metal salts in the aerobic tank was studied. The ferric chloride and aluminum chloride were chosen as the metal salts. The results showed that: the removal rate of TP rose with the Me/P (Me=Fe, Al)mass ratio increased, the influence on other performance of BAF by chemically enhanced synchronously was not severe, with TP in the effluent below the standard of 0.5mg/L; to ensure the concentration of effluent TP was less than 0.5mg/L, the optimum mass ratios of dosing were Fe/P=3, Al/P=2.5; proper aeration intensity could maintain the proper micro-flocculation state in BAF, which was helpful to TP removal.