Nishijima Wataru, Mukaidani Tsukasa, Okada Mitsumasa
Water Res. 2003 Jan;37(1):150-4. doi: 10.1016/s0043-1354(02)00257-9.
Multi-stage ozonation-biological treatment process for dissolved organic carbon (DOC) removal was evaluated to apply for drinking water treatment. Waters with different types of DOC were used, i.e. a reservoir water for drinking water supply, a secondary effluent from a municipal wastewater treatment plant and a solution of humic substances extracted from leaf mold. The multi-stage ozonation-biological treatment process was compared with conventional single-stage ozonation-biological treatment process. Amount of DOC removed in biological treatment was defined as amount of biodegradable dissolved organic carbon (BDOC) in influent of biological treatment. DOC removal in the multi-stage ozonation-biological treatment was higher than that in the conventional single-stage ozonation-biological treatment with the same total ozonation time for the reservoir water and humic substances solution. Moreover, three- or four-stage ozonation for 5 min followed by biological treatment (total ozonation time 15 or 20 min) showed higher removal of DOC than the single-stage ozonation (60 min) and biological treatment. The higher DOC removal in the multi-stage treatment was due to the production of BDOC by ozonation. The long-term ozonation was not effective to produce BDOC because most of ozone was utilized to oxidize BDOC produced in the early stage of ozonation. In the multi-stage treatment, ozonation was effective to decompose refractory DOC and to produce BDOC because BDOC was removed by biological treatment. However, multi-stage ozonation-biological treatment was not effective for the secondary effluent. The reason seems to be high concentration of ozone scavengers in that water and low reactivity of DOC for ozone.
对用于去除溶解有机碳（DOC）的多阶段臭氧化-生物处理工艺进行了评估，以应用于饮用水处理。使用了不同类型DOC的水，即作为饮用水供应的水库水、城市污水处理厂的二级出水以及从腐叶土中提取的腐殖物质溶液。将多阶段臭氧化-生物处理工艺与传统的单阶段臭氧化-生物处理工艺进行了比较。生物处理中去除的DOC量被定义为生物处理进水的可生物降解溶解有机碳（BDOC）量。对于水库水和腐殖物质溶液，在相同的总臭氧化时间下，多阶段臭氧化-生物处理中DOC的去除率高于传统单阶段臭氧化-生物处理。此外，5分钟的三阶段或四阶段臭氧化后进行生物处理（总臭氧化时间15或20分钟）显示出比单阶段臭氧化（60分钟）和生物处理更高的DOC去除率。多阶段处理中更高的DOC去除率归因于臭氧化产生的BDOC。长期臭氧化对产生BDOC无效，因为大部分臭氧被用于氧化臭氧化早期产生的BDOC。在多阶段处理中，臭氧化有效地分解了难降解的DOC并产生了BDOC，因为BDOC通过生物处理被去除。然而，多阶段臭氧化-生物处理对二级出水无效。原因似乎是该水中臭氧清除剂的浓度高以及DOC对臭氧的反应性低。
