• Membrane and Water Treatment
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• 제11권1호
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• pp.79-85
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• 2020

A single-stage deammonification with a sequencing batch reactor (SBR) that simultaneous nitritation, anaerobic ammonia oxidation (anammox), and denitrification (SNAD) occur in one reactor has been widely applied for sidestream of wastewater treatment plant. For the stable and well-balanced SNAD, a feeding strategy of influent wastewater is one of the most important operating factors in the single-stage deammonification SBR. In this study, single-stage deammonification SBR (working volume 30L) was operated to treat a high-strength ammonium wastewater (1200 mg NH₄⁺-N/L) with different feeding strategies (single feeding and nine-step feeding) under the condition without COD. Each cycle of the step feeding involved 6 sub-cycles consisted of aerobic and anoxic periods for partial nitritation (PN) and anammox, respectively. Contrary to unstable performance in the single feeding, the step feeding showed better deammonification performance (0.565 kg-N/m³/day). Under the condition with COD, however, the nitrogen removal rate (NRR) decreased to 0.403 kg-N/m³/day when the Nine-step feeding strategies had an additional denitrification period before sub-cycles for PN and anammox. The NRR was recovered to 0.518 kg-N/m³/day by introducing an enhanced multiple-step feeding strategy. The strategy had 50 cycles consisted of feed, denitrification, PN, and anammox, instead of repeated sub-cycles for PN and anammox. The multiple-step feeding strategy without sub-cycle showed the most stable and excellent deammonification performance: high nitrogen removal efficiency (98.6%), COD removal rate (0.131 kg-COD/m³/day), and COD removal efficiency (78.8%). This seemed to be caused by that the elimination of the sub-cycles might reduce COD oxidation during aerobic condition but increase the COD utilization for denitrification period. In addition, among various sensor values, the ORP pattern appeared to be applicable to monitor and control each reaction step for deammonification in the multiple-step feeding strategy without sub-cycle. Further study to optimize the number of multiple-step feeding is still needed but these results show that the multiple-step feeding strategy can contribute to a well-balanced SNAD for deammonification when treating high-strength ammonium wastewater with COD in the single-stage deammonification SBR.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2007년도 추계학술발표회
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• pp.97-102
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• 2007

축산폐수는 유기물 및 질소분의 농도가 높아 발생량에 비해 오염 부하량이 큰 폐수이다. 따라서 본 실험에서는 축산폐수에 고온호기성소화공정을 적용하여 고농도의 질소분의 제거효율을 조사해 보았다. 실험은 체류시간과 공기주입량을 변화시켜가며 수행하였다. 반연속식으로 운전된 본 실험 결과 높은 SCOD 제거효율을 얻을 수 있었다. 반면 TCOD의 경우 SCOD보다는 적은 제거율을 나타내었다. 질소분의 제거의 경우 HRT 3 days일 때 79%의 NH4-N이 제거되었으며, 체류시간이 감소하면서 그 제거량도 줄어드는 것으로 나타났다. 실험기간 중 수행된 가스분석에 있어서 유입된 질소분 중 일부가 N2O gas로 전환됨을 발견하였으며, 따라서 생물학적 탈암모니아가 일어남을 알 수 있었다. 실험기간 중 반응조 내에 NO2 및 NO3는 존재하지 않는 것으로 나타났다. HRT 3 days의 경우 유입된 질소 중 213.4%가 N20 gas로 전환되었으며, HRT 0.5 day 의 경우 4.5% 가 N2O gas로 변환되어 체류시간이 감소할수록 생물학적인 N2O gas 전환량이 줄어드는 것으로 나타났다.