This study investigates the simultaneous accumulation of S^(0) and NO_(2)^(-)during short-cut sulfur autotrophic denitrification(SSADN)in response to 0-35 mg/L hydroxylamine(NH_(2)OH)addition.At a dosage of 15 mg/L NH...This study investigates the simultaneous accumulation of S^(0) and NO_(2)^(-)during short-cut sulfur autotrophic denitrification(SSADN)in response to 0-35 mg/L hydroxylamine(NH_(2)OH)addition.At a dosage of 15 mg/L NH_(2)OH,the accumulation of NO_(2)^(-)-N peaked at 32.49±1.33 mg/L,which is 1.65 times higher than that of the control.The addition of NH_(2)OH facilitates the retention of S^(0) in the system.Enzyme assays indicated significant discrepancies in the enhanced NO_(2)^(-)-N reductase(NAR)and NO_(2)^(-)-N reductase(NIR)activities induced by NH_(2)OH are responsible for the excellent NO_(2)^(-)-N production.These results are supported by the corresponding NO_(3)^(-)-N reduction genes(napA,narG)and NO_(2)^(-)-N reduction genes(nirS,nirK).In addition,the abundance of sulfur oxidation genes(soxB)decreases with increasing NH_(2)OH dosage,inhibiting further oxidation of S^(0) to SO_(4)^(2-).The accumulation of NO_(2)^(-)-N and S^(0) increases from 45.8% and 36.8% to 70.04% and 52.52%,respectively,with the addition of 2 mg/L NH_(2)OH in the continuous-flow up-flow anaerobic sludge blanket(UASB)reactor.展开更多
基金supported by the Shandong Provincial Natural Science Foundation(No.ZR2019MEE038,ZR202110260011)the Scientific research project of Xinjiang oilfield company(No.2022C4004)the Qingdao West-Coast Economic New Area Scientific and Technological Project of the special open competition mechanism to select the best candidates(2022-14).
文摘This study investigates the simultaneous accumulation of S^(0) and NO_(2)^(-)during short-cut sulfur autotrophic denitrification(SSADN)in response to 0-35 mg/L hydroxylamine(NH_(2)OH)addition.At a dosage of 15 mg/L NH_(2)OH,the accumulation of NO_(2)^(-)-N peaked at 32.49±1.33 mg/L,which is 1.65 times higher than that of the control.The addition of NH_(2)OH facilitates the retention of S^(0) in the system.Enzyme assays indicated significant discrepancies in the enhanced NO_(2)^(-)-N reductase(NAR)and NO_(2)^(-)-N reductase(NIR)activities induced by NH_(2)OH are responsible for the excellent NO_(2)^(-)-N production.These results are supported by the corresponding NO_(3)^(-)-N reduction genes(napA,narG)and NO_(2)^(-)-N reduction genes(nirS,nirK).In addition,the abundance of sulfur oxidation genes(soxB)decreases with increasing NH_(2)OH dosage,inhibiting further oxidation of S^(0) to SO_(4)^(2-).The accumulation of NO_(2)^(-)-N and S^(0) increases from 45.8% and 36.8% to 70.04% and 52.52%,respectively,with the addition of 2 mg/L NH_(2)OH in the continuous-flow up-flow anaerobic sludge blanket(UASB)reactor.
