Anaerobic whey treatment by a stirred sequencing batch reactor (ASBR): effects of organic loading and supplemented alkalinity

An assessment was made of cheese whey treatment in a mechanically stirred anaerobic sequencing batch reactor (ASBR) containing granular biomass. The effect of increasing organic load and decreasing influent alkalinity supplementation (as sodium bicarbonate) was analyzed. The reactor operated on 8-h cycles with influent COD concentrations of 500, 1000, 2000 and 4000 mg/L, corresponding to volumetric organic loads of 0.6 to 4.8 mgCOD/L.d. Organic COD removal efficiencies were always above 90% for filtered samples. These results were obtained with an optimized alkalinity supplementation of 50% (ratio between mass of NaHCO3 added and mass of influent mgNaHCO3/mgCOD) in the assays with 500 and 1000 mgCOD/L and of 25% in the assays with 2000 and 4000 mgCOD/L. Initial alkalinity supplementation was equal to the mass of influent COD (100%). The system showed formation of viscous polymer-like substances. These were probably of microbiological origin occurring mainly at influent CODs of 2000 and 4000 mg/L and caused some biomass flotation. This could, however be controlled to enable efficient and stable reactor operation.     

Correlation of anaerobic ammonium oxidation and denitrification

The feasibility of the nitrous organic wastewater treated was studied in seven anaerobic sequencing batch reactors（ASBRs） （0^#-6^#） which had been run under stable anaerobic ammonium oxidation （Anammox）. By means of monitoring and data analysis of COD, NH4^#-N, NO2^--N, NO3^--N and pH, and of microbial test, the results revealed that the optimal Anammox performance was achieved from 2^# reactor in which COD/NH4^＋ -N was 1.65, Anammox bacteria and denitrification bacteria could coexist, and Anammox reaction and denitrification reaction could occur simultaneously in the reactors. The ratio of NH4^＋-N consumed ： NO2^- -N consumed ： NO3^- -N produced was 1：1.38：0.19 in 0^# reactor which was not added glucose in the wastewater. When different ratio of COD and NH4^＋-N was fed for the reactors, the ratio of NO2^- -N consumed： NH4^＋-N consumed was in the range of 1.51-2.29 and the ratio of NO;-N produced： NH4^＋ -N consumed in the range of 0 -0.05.     

锥组对ASBR性能的影响及其流场模拟

结合计算流体动力学(CFD)流场模拟,分析研究了二次流场下锥组对厌氧序批式反应器(ASBR)处理效果和污泥性状的影响。结果表明:锥组改善了双层搅拌桨下的二次流场,增强了ASBR的混合和污泥沉降效果,促进了污泥颗粒化,增加了污泥浓度,从而提高了处理效率和抗有机负荷冲击能力。在试验范围内,有机负荷越高,锥组对处理效果的改善越明显,在COD容积负荷为1.2 kg/(m3·d)时,设有锥组的ASBR出水ρ(COD)为450 mg/L,而未设锥组的为930 mg/L;通过锥组的浅层沉降作用和污泥在锥壁上的滚动压缩作用,污泥沉降效果明显提高,颗粒化速度加快,在运行初期设有锥组的ASBR即可在15 min内沉至出水液面以下,而未设锥组的ASBR需要约30 min,且在40 d时,R2中有45.4%污泥实现了颗粒化,而R1中只有32.5%。     

ASBR工艺的研究及应用

对厌氧序批式工艺(ASBR工艺)进行了系统分析。分析包括工艺过程、工艺特点、工艺的调控及在国内外的应用等。着重研究了该工艺的影响因素,如温度、碱度、进水时间与反应时间比、反应器尺寸等。分析研究表明,ASBR工艺是一种新型高效厌氧节能的工艺,有许多优点,具有广泛的应用前景,非常适合于处理我国复杂的废水水质。     

硝基苯降解菌在厌氧序批式反应器中处理硝基苯废水的应用

通过接种硝基苯降解菌于厌氧序批式反应器（ASBR），研究静态试验条件下和厌氧序批式工艺对硝基苯的降解规律，研究表明，应用生物强化技术处理硝基苯废水，具有很高的处理效率。     

ASBR法研究进展与展望

综合论述了ASBR法的工作原理、特点及研究现状 ,展望了ASBR法在废水处理中的应用前景。     

废水厌氧生物处理技术综述与研究进展

本文系统总结了污水厌氧生物处理技术发展沿革、技术现状与研究进展 ,并对各技术的优缺点进行了比较 ,指出了技术研究的关键与应用前景     

低基质浓度下pH和DO对厌氧氨氧化反应效能的影响

在实验室稳定运行的ASBR反应器基础上,以人工模拟废水为原水,分别研究了p H值、DO对厌氧氨氧化反应器脱氮性能的影响,旨在找出厌氧氨氧化反应最佳的p H值范围,并考察过高的进水DO对厌氧氨氧化污泥脱氮效能的影响及厌氧氨氧化污泥对高浓度DO的抵抗性。结果表明:厌氧氨氧化反应器的最适进水p H为7.5~8.0,此范围内反应器脱氮性能良好且稳定,NH+4-N去除率达到90.2%,NO-2-N去除率达到91.1%。而厌氧氨氧化菌对DO十分敏感,水体中含氧量过高会产生明显的抑制作用,但控制进水溶解氧浓度后,厌氧氨氧化反应器脱氮性能可迅速恢复。一定时间内高浓度DO对厌氧氨氧化污泥的活性抑制是可以恢复的。     

ASBR处理高浓度悬浮固体废物的工艺特性

在水力停留时间(HRT)分别为20、10、7.5、5d的条件下,进行了中温、高温厌氧序批式反应器(ASBR)处理热水解污泥的试验,在此基础上总结了ASBR处理高浓度悬浮固体废物的工艺特性.ASBR可以有效积累悬浮固体从而保持较高的固体浓度,但ASBR存在一“临界点”,即最大积累悬浮固体的能力,超过此临界点,反应器运行不稳.在稳态运行条件下,ASBR能保持较高固体停留时间(SRT)和微生物平均细胞停留时间(MCRT),在处理热水解污泥时,SRT和MCRT分别是水力停留时间(HRT)的2.53～3.73倍、2.03～3.14倍.因此,与传统的连续流搅拌反应器(CSTR)相比,ASBR的处理效率提高7.13%～34.68%.     

有机碳源条件下厌氧氨氧化ASBR反应器中的主要反应

采用5个已稳定运行在厌氧氨氧化状态的ASBR反应器,通过COD、氨氮、亚硝酸盐氮、硝酸盐氮、pH等指标的监测和好氧硝化菌、异养反硝化菌的测定,研究了不同有机碳源条件下反应器中发生的主要反应.结果表明,反应器中存在好氧硝化菌、异养反硝化菌和厌氧氨氧化菌.在COD、氨氮、亚硝酸盐氮等存在条件下,可发生好氧硝化、厌氧氨氧化和异养反硝化反应,先是好氧硝化反应、厌氧氨氧化反应和异养反硝化反应共存,其后依次是异养反硝化反应和厌氧氨氧化反应占主导地位.当C/NO₂^--N在1.7～1.9范围内时,C/NH₄⁺-N为1.7的1号反应器具有最佳的厌氧氨氧化效果,反应结束时其COD去除率、NH₄⁺-N去除率、NO₂^--N去除率分别为100%、81.7%和74.4%.