Kaarela Outi E, Härkki Heli A, Palmroth Marja R T, Tuhkanen Tuula A
a Department of Chemistry and Bioengineering , Tampere University of Technology , P.O. Box 541, FI-33101 Tampere , Finland.
Environ Technol. 2015 Mar-Apr;36(5-8):681-92. doi: 10.1080/09593330.2014.958542. Epub 2014 Sep 22.
Granular activated carbon (GAC) filtration enhances the removal of natural organic matter and micropollutants in drinking water treatment. Microbial communities in GAC filters contribute to the removal of the biodegradable part of organic matter, and thus help to control microbial regrowth in the distribution system. Our objectives were to investigate bacterial community dynamics, identify the major bacterial groups, and determine the concentration of active bacterial biomass in full-scale GAC filters treating cold (3.7-9.5°C), physicochemically pretreated, and ozonated lake water. Three sampling rounds were conducted to study six GAC filters of different operation times and flow modes in winter, spring, and summer. Total organic carbon results indicated that both the first-step and second-step filters contributed to the removal of organic matter. Length heterogeneity analysis of amplified 16S rRNA genes illustrated that bacterial communities were diverse and considerably stable over time. α-Proteobacteria, β-Proteobacteria, and Nitrospira dominated in all of the GAC filters, although the relative proportion of dominant phylogenetic groups in individual filters differed. The active bacterial biomass accumulation, measured as adenosine triphosphate, was limited due to low temperature, low flux of nutrients, and frequent backwashing. The concentration of active bacterial biomass was not affected by the moderate seasonal temperature variation. In summary, the results provided an insight into the biological component of GAC filtration in cold water temperatures and the operational parameters affecting it.
颗粒活性炭（GAC）过滤可增强饮用水处理中天然有机物和微污染物的去除效果。GAC滤池中微生物群落有助于去除有机物的可生物降解部分，从而有助于控制配水系统中的微生物再生长。我们的目标是研究全尺寸GAC滤池中细菌群落动态，确定主要细菌类群，并测定处理低温（3.7 - 9.5°C）、经过物理化学预处理和臭氧处理的湖水的GAC滤池中活性细菌生物量的浓度。进行了三轮采样，以研究冬季、春季和夏季运行时间和水流模式不同的六个GAC滤池。总有机碳结果表明，第一步和第二步滤池均有助于有机物的去除。对扩增的16S rRNA基因进行长度异质性分析表明，细菌群落多样且随时间相当稳定。α-变形菌纲、β-变形菌纲和硝化螺旋菌在所有GAC滤池中占主导地位，尽管各个滤池中优势系统发育类群的相对比例有所不同。以三磷酸腺苷衡量的活性细菌生物量积累由于低温、低营养通量和频繁反冲洗而受到限制。活性细菌生物量浓度不受适度季节温度变化的影响。总之，这些结果深入了解了低温下GAC过滤的生物组成部分以及影响它的运行参数。
