It is common that 2,4,6-trichlorophenol （TCP） coexists with nitrate or nitrite in industrial wastewaters. In this work, simultaneous reductive dechlorination of TCP and denitrification of nitrate or nitrite competed...It is common that 2,4,6-trichlorophenol （TCP） coexists with nitrate or nitrite in industrial wastewaters. In this work, simultaneous reductive dechlorination of TCP and denitrification of nitrate or nitrite competed for electron donor, which led to their mutual inhibition. All inhibitions could be relieved to a certain degree by augmenting an organic electron donor, but the impact of the added electron donor was strongest for TCP. For simultaneous reduction ofTCP together with nitrate, TCP＇s removal rate value increased 75% and 150%, respectively, when added glucose was increased from 0.4 mmol· L^-1 to 0.5 mmol· L^-1 and to 0.76 mmol· L^-1 For comparison, the removal rate for nitrate increased by only 25% and 114% for the same added glucose. The relationship between their initial biodegradation rates versus their initial concentrations could be represented well with the Monod model, which quantified their half-maximum-rate concentration （Ks value）, and Ks values for TCP, nitrate, and nitrite were larger with simultaneous reduction than independent reduction. The increases in Ks are further evidence that competition for the electron donor led to mutual inhibition. For bioremediation of wastewater containing TCP and oxidized nitrogen, both reduction reactions should proceed more rapidly if the oxidized nitrogen is nitrite instead of nitrate and if readily biodegradable electron acceptor is augmented.展开更多
基金Acknowledgements The authors acknowledge the financial support of the ability construction project of local Colleges and Universities in Shanghai （No. 16070503000）, Special Fund of State Key Joint Laboratory of Environment Simulation and Pollution Control （No. 16K10ESPCT）, Shanghai Gaofeng ＆ Gaoyuan Project for University Academic Program Development, and the United States National Science Foundation （No. O651794）.
文摘It is common that 2,4,6-trichlorophenol （TCP） coexists with nitrate or nitrite in industrial wastewaters. In this work, simultaneous reductive dechlorination of TCP and denitrification of nitrate or nitrite competed for electron donor, which led to their mutual inhibition. All inhibitions could be relieved to a certain degree by augmenting an organic electron donor, but the impact of the added electron donor was strongest for TCP. For simultaneous reduction ofTCP together with nitrate, TCP＇s removal rate value increased 75% and 150%, respectively, when added glucose was increased from 0.4 mmol· L^-1 to 0.5 mmol· L^-1 and to 0.76 mmol· L^-1 For comparison, the removal rate for nitrate increased by only 25% and 114% for the same added glucose. The relationship between their initial biodegradation rates versus their initial concentrations could be represented well with the Monod model, which quantified their half-maximum-rate concentration （Ks value）, and Ks values for TCP, nitrate, and nitrite were larger with simultaneous reduction than independent reduction. The increases in Ks are further evidence that competition for the electron donor led to mutual inhibition. For bioremediation of wastewater containing TCP and oxidized nitrogen, both reduction reactions should proceed more rapidly if the oxidized nitrogen is nitrite instead of nitrate and if readily biodegradable electron acceptor is augmented.
