A pilot study for nitrifying treatment of wastewater from fertilizer production using a gas–liquid–solid three-phase flow airlift loop bioreactor

✍ Scribed by Jianping Wen; Xianling Liu; Qing Yuan; Xueming Zhao

• Publisher: Wiley (John Wiley & Sons)
• Year: 2006
• Tongue: English
• Weight: 166 KB
• Volume: 81
• Category: Article
• ISSN: 0268-2575
• DOI: 10.1002/jctb.1528

✦ Synopsis

Abstract

An 80 m^3^ pilot‐scale gas–liquid–solid three‐phase flow airlift loop bioreactor (ALR) with a low ratio of height to diameter, in which a biological membrane replaced the activated sludge, was used in the nitrifying treatment of a real effluent from a fertilizer plant. The influences of pH value, air influx (Q~g~) and hydraulic residence time (HRT) on the reductions in chemical oxygen demand (COD) and ammonia nitrogen (NH~4~‐N) were investigated and are discussed herein. The optimum operating conditions were obtained at a pH value of 7.0–8.0, air influx of 500 m^3^ h^−1^ and an HRT of 10 h. Under these optimum conditions, the effluent COD and NH~4~‐N were less than 50 mg L^−1^ and 10 mg L^−1^ for a 40‐day run, which were far below the primary discharge standard for the chemical fertilizer industry in the People's Republic of China (COD ≤ 100 mg L^−1^ and NH~4~‐N ≤ 40 mg L^−1^). Furthermore, this pilot‐scale airlift loop bioreactor generated only one‐quarter of the sludge waste compared with the traditional activated sludge process. Copyright © 2006 Society of Chemical Industry