Istanbul Medeniyet University, Bioengineering Department, Goztepe, Istanbul, Turkey.
Harran University, Environmental Engineering Department, Osmanbey Campus, 63000 Sanliurfa, Turkey; Yeditepe Treatment Company, Kucukbakkalkoy, Ataşehir, Istanbul, Turkey.
Water Res. 2014 Mar 1;50:278-86. doi: 10.1016/j.watres.2013.12.005. Epub 2013 Dec 12.
Nitrate and chromate can be present together in water resources as nitrate is a common co-contaminant in surface and ground waters. This study aims at comparatively evaluating simultaneous chromate and nitrate reduction in heterotrophic and sulfur-based autotrophic denitrifying column bioreactors. In sulfur-based autotrophic denitrification process, elemental sulfur and nitrate act as an electron donor and an acceptor, respectively, without requirement of organic supplementation. Autotrophic denitrification was complete and not adversely affected by chromate up to 0.5 mg/L. Effluent chromate concentration was <50 μg/L provided that influent chromate concentration was ≤0.5 mg/L. Heterotrophic denitrification performance was not adversely affected even at 20 mg/L chromate and complete chromate reduction was attained up to 10 mg/L. Although autotrophic denitrification rate was much lower compared with heterotrophic one, it may be preferred in drinking water treatment due to the elimination of organic supplementation and the risk of treated effluent contamination.
硝酸盐和铬酸盐可以同时存在于水资源中，因为硝酸盐是地表水和地下水的常见共污染物。本研究旨在比较评价异养和硫基自养反硝化柱生物反应器中同时还原铬酸盐和硝酸盐的效果。在硫基自养反硝化过程中，元素硫和硝酸盐分别作为电子供体和受体，而无需补充有机物质。自养反硝化完全，并且在 0.5mg/L 以下的铬酸盐浓度下不受影响。只要进水铬酸盐浓度≤0.5mg/L，出水中的铬酸盐浓度<50μg/L。即使在 20mg/L 的铬酸盐浓度下，异养反硝化性能也不受影响，最高可达 10mg/L 的铬酸盐完全还原。尽管与异养反硝化相比，自养反硝化速率要低得多，但由于消除了有机补充和处理后废水污染的风险，它可能更适合饮用水处理。
