A comparison of biological nutrient removal in intermittent cyclic and continuous activated sludge systems

✍ Scribed by Kin-man Ho; Paul F. Greenfield; Linda L. Blackall; Peter R.F. Bell; Andre Krol

• Book ID: 103934788
• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 587 KB
• Volume: 11
• Category: Article
• ISSN: 0921-3449
• DOI: 10.1016/0921-3449(94)90086-8

✦ Synopsis

An assessment was made of biological phosphorus and nitrogen removal and related sludge bulking control in both intermittent cyclic and continuous activated sludge systems. Experimental results from a laboratory-scale investigation using fermented domestic sewage indicated the advantages of achieving high levels of P and N removal and good sludge-settling properties using the intermittent cyclic process, as compared to the continuous process. The modified intermittently fed and decanted system incorporating non-mixing sequences produced an effluent quality of NO3-N < 5 mg L-J, PO4-P < 1 mg L -~ and NH3-N< 2 mg L -~, with a non-bulking sludge having a sludge volume index < 120 mL g-1, despite unfavourable influent characteristics (TCOD: TKN < 7, TKN > 60 mg L-1, TP-9 mg Land RBCOD < 30 mg L-' ). In contrast, the modified 4-stage Bardenpho process could not achieve effluent NO3-N and PO4-P concentrations of < 10 and < 1 mg L-l, respectively. The sludge volume index (SVI) values were always higher than 250 mL g-~ and occasionally reached as high as 422 mL g-~. The causative filaments were low F: M growers -Types 0041/0675.