Department of Civil Engineering, University of Toronto, 35 St. George Street, Toronto, ON M5S1A4, Canada.
Department of Civil Engineering, University of Toronto, 35 St. George Street, Toronto, ON M5S1A4, Canada.
Water Res. 2018 Jan 1;128:1-9. doi: 10.1016/j.watres.2017.10.019. Epub 2017 Oct 13.
Media type is a critical design consideration when implementing biofiltration for drinking water treatment. Granular activated carbon (GAC) has been shown to provide superior performance when compared to a wide range of media types, largely due to its higher surface area. Engineered ceramic media is an attractive alternative to GAC as it has a similar surface area but at a lower cost. This pilot-scale biofiltration study compared the performance of GAC, anthracite and two different effective sizes of ceramic (CER) media (1.0 mm and 1.2 mm), in terms of dissolved organic carbon (DOC), head loss, turbidity, and disinfection by-product formation potential (DBPFP). Biological acclimation was monitored using adenosine tri-phosphate (ATP) measurements; biomass was further examined using laccase and esterase enzyme activity assays. When compared to other media types examined, biological GAC had higher (p > 0.05) removals of DOC (9.8 ± 3.8%), trihalomethane formation potential (THMFP, 26.3 ± 10.2%), and haloacetic acid formation potential (HAAFP, 27.2 ± 14.0%). CER media required 6-7 months to biologically acclimate, while filters containing GAC and anthracite were biologically active (>100 ng of ATP/g media) following 30-45 days of operation. Once acclimated, ATP values of 243 and 208 ng/g attained for CER 1.0 and 1.2, respectively, were statistically comparable to GAC (244 ng/g) and higher than anthracite (110 ng/g), however this did not translate into greater organics removal. Esterase and laccase enzyme kinetics were highest for GAC, while CER was shown to have greater biodegradation potential than anthracite. The four media types attained similar turbidity reduction (p > 0.05), however ceramic media filters were observed to have run times which were 1.5-2.3 times longer when compared to anthracite, which could represent potential cost savings in terms of energy for pumping and backwash requirements. Overall, ceramic media was shown to be a potential alternative to anthracite when considering biofiltration, especially during cold water conditions (T < 10 °C).
在饮用水处理中实施生物过滤时，媒体类型是一个关键的设计考虑因素。与广泛的媒体类型相比，颗粒活性炭 (GAC) 已被证明具有卓越的性能，这主要归因于其更高的表面积。工程陶瓷介质是 GAC 的一种有吸引力的替代品，因为它具有相似的表面积，但成本更低。这项中试规模的生物过滤研究比较了 GAC、无烟煤和两种不同有效粒径的陶瓷 (CER) 介质 (1.0 毫米和 1.2 毫米) 在溶解有机碳 (DOC)、水头损失、浊度和消毒副产物形成潜力 (DBPFP) 方面的性能。通过腺苷三磷酸 (ATP) 测量监测生物驯化；使用漆酶和酯酶酶活性测定进一步检查生物量。与其他检查的媒体类型相比，生物 GAC 对 DOC（9.8±3.8%）、三卤甲烷生成潜力（THMFP，26.3±10.2%）和卤乙酸生成潜力（HAAFP，27.2±14.0%）的去除率更高（p>0.05）。CER 介质需要 6-7 个月才能进行生物驯化，而含有 GAC 和无烟煤的过滤器在运行 30-45 天后就具有生物活性（>100ng ATP/g 介质）。一旦驯化，CER 1.0 和 1.2 的 ATP 值分别达到 243 和 208ng/g，与 GAC（244ng/g）相当，高于无烟煤（110ng/g），但这并未转化为更大的有机物去除率。酯酶和漆酶的酶动力学对 GAC 最高，而 CER 显示出比无烟煤更大的生物降解潜力。四种介质类型的浊度去除率相似（p>0.05），但与无烟煤相比，陶瓷介质过滤器的运行时间长 1.5-2.3 倍，这可能代表在泵送和反冲洗要求方面的潜在成本节约。总体而言，在考虑生物过滤时，陶瓷介质被证明是无烟煤的一种潜在替代品，特别是在冷水条件下（T<10°C）。
