CIESC Journal ›› 2010, Vol. 61 ›› Issue (3): 732-739.

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Granulation and characteristics of extracellular polymers of anammox sludge in high-load EGSB reactor

TANG Chongjian;ZHENG Ping;WANG Caihua;ZHANG Jiqiang;CHEN Jianwei;DING Shuang   

  • Online:2010-03-05 Published:2010-03-05

高负荷厌氧氨氧化EGSB反应器的运行及其颗粒污泥的ECP特性

唐崇俭;郑平;汪彩华;张吉强;陈建伟;丁爽   

  1. 浙江大学环境工程系

Abstract:

High effectiveness is one of the most attractive advantages of the anaerobic ammonium oxidation (anammox) process for nitrogen removal from ammonium-rich wastewater. Granulation is considered to play a vital role in development of high-load bioreactors. The hydraulic retention time (HRT) of the 1.1 L anammox EGSB (expanded-granular sludge bed) reactor was progressively shortened from 6.9 h to 0.30 h; while the influent nitrite concentration was fixed at 360 mg·L-1 and the effluent recycling was maintained at 0.5 constantly. A super high nitrogen removal rate, 50.75 kg·m-3·d-1 was recorded, which was 2 times of the highest value reported before. Granulation of the anammox microorganisms occurred in the high-load anammox EGSB reactor. The average diameter of the high-load anammox granules was (2.51±0.91)mm and the specific anammox activity reached 1.899 kg·(g VSS)-1·d-1. The extracellular polymers (ECP) content was 143.00 mg·(g VSS)-1, which was amazingly high when compared to heterotrophic microbial granules. The extracellular proteins increased at a higher rate along with the increase of hydrodynamic shear stress, resulting in over-production of extracellular proteins. Thus the stability of the anammox granules decreased and sludge washout became inevitable.

Key words: 厌氧氨氧化, EGSB反应器, 颗粒污泥, 胞外多聚物, 生物脱氮

摘要:

高效性是厌氧氨氧化(anaerobic ammonium oxidation, anammox)生物脱氮工艺的优势,污泥颗粒化则是生物反应器高效性的重要原因。控制进水亚硝酸盐浓度为360 mg·L-1,回流比为0.5,经过230 d的连续运行,逐步将厌氧氨氧化膨胀颗粒污泥床(expanded-granular sludge bed, EGSB)反应器(1.1 L)的水力停留时间由6.9 h缩短至0.30 h,获得的容积基质氮去除速率为50.75 kg·m-3·d-1,是原有世界最高水平的2倍。在此工况下获得的高负荷厌氧氨氧化颗粒污泥的平均粒径为(2.51±0.91)mm,比污泥厌氧氨氧化活性为1.899 kg·(kg VSS)-1·d-1,胞外多聚物(extracellular polymers, ECP)总含量达143.00 mg·(g VSS)-1。随着反应器容积基质氮去除速率的提高,反应器内厌氧氨氧化颗粒污泥胞外多聚物含量增加,其中蛋白质含量增加更快,蛋白质的“超量产生”致使颗粒污泥的PN/PS增大,易随水流失。

关键词: 厌氧氨氧化, EGSB反应器, 颗粒污泥, 胞外多聚物, 生物脱氮