• 대한환경공학회지
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• 제30권7호
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• pp.700-704
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• 2008

혐기성 암모니아 산화공정에서 nitrite는 저해인자로 잘 알려져 있고, 최근에는 유리 암모니아 역시 anammox bacteria에 저해 영향을 주는 것으로 보고되고 있다. 유입수의 암모니아와 아질산의 비율이 연속운전에서 효과적인 질소제거에 중요한 인자가 되며, 연속운전 반응기에서는 유리 암모니아와 아질산의 축적을 방지하기 위해 유입수의 NH$_3$-N/NO$_2$-N-N비를 조절할 필요가 있다. 이에 본 연구에서는 다섯 가지 종류의 NH$_3$-N/NO$_2$-N-N비를 회분식 실험을 통해 잔류 암모니아성 질소와 아질산성 질소의 농도를 최소화하는 비를 조사하였다. 회분식 실험 결과 실험 26시간 후에 1.00 : 1.30의 비에서 88%에 달하는 총질소 제거율이 나타났다. 그리고 혐기성 암모늄 산화 반응은 0차 반응을 나타내었고, 암모니아와 아질산의 반응 속도상수는 1.00 : 1.30의 비에서 각각 7.66 mg/L$\cdot$hr과 11.89 mg/L$\cdot$hr로 가장 높게 나타났다. 혐기성 암모늄 산화균 활성도를 측정해본 결과 1.00 : 1.15의 비에서 미생물의 활성도가 가장 우수한 것으로 나타났다. 회분식 실험의 결과를 통해, 이론적 반응비과 비슷한 1.00:1.30에서는 반응속도가 크고 총질소 제거율도 높은 반면 혐기성 암모늄 산화균은 이론적 반응비보다 다소 낮은 아질산 농도에서 안정하다는 것을 확인할 수 있었다.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2005년도 International Meeting of the Microbiological Society of Korea
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• pp.169-169
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• 2005

• 한국물환경학회지
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• 제39권5호
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• pp.390-395
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• 2023

The feasibility of applying the shortcut nitrogen removal process to treat livestock wastewater on individual farms was examined, and appropriate operating parameters were established. As a result,, it was determined that the nitrification reaction was carried out under 550 mg/L of ammonium nitrogen concentration, but it was less effective under conditions of high ammonia concentration. Consequently, it was confirmed that a partial injection of inflow water was necessary to minimize the effects of ammonia toxicity. Following the sequential batch reactor (SBR) operation results, it was difficult to achieve the effluent quality standard without an external carbon source. Also, selection of the appropriate hydraulic retention time was critical for the optimal SBR operation. Following the livestock farm application, with external carbon source injecting, the total nitrogen concentration in the effluent was 85.1 mg/L. This result revealed that the standard could be accomplished through a single treatment on individual livestock farms. The ratio of nitrite nitrogen to ammonia nitrogen in the effluent was verified to be suitable for implementing the anammox process with a 10 days of hydraulic retention time. This study demonstrated the potential applicability of process in the future. However, in order to apply to livestock farms, managing variations in wastewater load across individual farms and addressing reduced nitrogen oxidation efficiency during the winter season are crucial.

• 한국물환경학회지
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• 제22권6호
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• pp.1014-1021
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• 2006

SMMIAR (Submerged Moving Media Intermittent Aeration Reactor) Process is a very efficient system which remove ammonia to nitrogen gas in one reactor. In this study, we determined the diversity of ammonia oxidizing bacteria and denitrifying bacteria using specific PCR amplification and the clone library construction. An ammonia monooxygenase gene(amoA) was analyzed to investigate the diversity of nitrifiers. Most of amoA gene fragments (27/29, 93%) were same types and they are very similar (>99%) to the sequences of Nitrosomonas europaea and other clones isolated from anoxic ammonia oxidizing reactors. ANAMMOX related bacteria have not determined by specific PCR amplification. A nitrite reductase gene(nirK) was analyzed to investigate the diversity of denitrifying bacteria. About half (9/20, 45%) of denitrifiers were clustered with Rhodobacter and most of others were clustered with Mesorhizobium (6/20, 30%) and Rhizobium (3/20, 15%). All of these nirK gene clones were clustered in alpha-Proteobacteria and this result is coincide with other system which also operate nitrification and denitrification in one reactor. The molecular monitoring of the population of nitrifiers and denitrifiers would be helpful for the system stabilization and scale-up.

• 한국물환경학회지
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• 제34권1호
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• pp.121-131
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• 2018

Domestic sewage treatment plants (STPs) consume about 0.5 % of total electric energy produced annually, which is equivalent to 207.7 billion Korean won per year. To minimize the energy consumption and as a way of mitigating the depletion of energy sources, the sewage treatment strategy should be improved to the level of "energy positive". The core processes for the energy positive sewage treatment include A-stage for energy recovery and B-stage for energy-efficient nitrogen removal. The integrated process is known as the A/B-process. In A-stage, chemically enhanced primary treatment (CEPT) or high rate activated sludge (HRAS) processes can be utilized by modifying the primary settling in the first stage of sewage treatment. CEPT utilizes chemical coagulation and flocculation, while HRAS applies returned activated sludge for the efficient recovery of organic contents. The two processes showed organic recovery efficiencies ranging from 60 to 70 %. At a given recovery efficiency of 80 %, 17.3 % of energy potential ($1,398kJ/m^3$) is recovered through the anaerobic digestion and combustion of methane. Besides, anaerobic membrane bioreactor (AnMBR) can recover 85% of organic contents and generate $1,580kJ/m^3$ from the sewage. The recovered energy is equal to the amount of energy consumption by sewage treatment equipped with anaerobic ammonium oxidation (ANAMMOX)-based B-stage, $810{\sim}1,620kJ/m^3$. Therefore, it is possible to upgrade STPs as efficient as energy neutral. However, additional novel technologies, such as, fuel cell and co-digestion, should be applied to achieve "energy positive" sewage treatment.

• Environmental Engineering Research
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• 제25권3호
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• pp.309-315
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• 2020

Slaughterhouse wastewater (SWW) is characterized as one of the most harmful agriculture and food industrial wastewaters due to its high organic content. The emissions of SWW would cause eutrophication of surface water and pollution of groundwater. This study developed a pilot scale anaerobic-aerobic slaughterhouse wastewater treatment process (AASWWTP) to enhance the chemical oxygen demand (COD) and total nitrogen (TN) removal. The optimum supernatant reflux position and ratio for TN removal were investigated through the modified Box-Behnken design (BBD) experiments. Results showed that COD could be effectively reduced over the whole modified BBD study and the removal efficiency was all higher than 98%. The optimum reflux position and ratio were suggested to be 2 alure and 100%, respectively, where effluent TN concentration was satisfied with the forthcoming Chinese discharge standard of 25 mg/L. Anaerobic digestion and ammonia oxidation were considered as the main approaches for COD and TN removal in the AASWWTP. The results of inorganic nutrients (K⁺, Na⁺, Ca²⁺ and Mg²⁺) indicated that the SWW was suitable for biological treatment and the correspondingly processes such as AASWWTP should be widely researched and popularized. Therefore, AASWWTP is a promising technology for SWW treatment but more research is needed to further improve the operating efficiency.

• 상하수도학회지
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• 제24권1호
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• pp.51-62
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• 2010

The high concentration of N in the wastewater from livestock farming generally renders the efficiency of the wastewater treatment. Therefore, removal of N in livestock wastewater is crucial for successful treatment. The current study was conducted to investigate the optimum conditions for partial nitrification under anaerobic condition following nitritation in TPAD-BNR(two-phase anaerobic digestion-biological nitrogen removal) operating system. Sequential operating test to stimulate partial nitrification in reactor showed that partial nitrification occurred at a ratio of 1.24 in $NO_2{^-}$-N:$NH_4{^+}$-N. With this result, a wide range of factors affecting stable nitritation were examined through regression analysis. In the livestock wastewater treatment procedure, the hydraulic retention time (HRT) and pH range for optimum nitrite accumulation in the reactor were 1-1.5 days and 7-8, respectively. It was appeared that accumulation of $NO_2{^-}$-N in the reactor is due to inhibition of the $NO_2{^-}$-N oxidizer by free ammonia (FA) while the effect of free nitrous acid was minimal. Nitrification was not influenced by DO concentration at a range of 2.0-3.0 mg/L and the difference in the growth rate between $NH_4{^+}$-N oxidizer and $NO_2{^-}$-N oxidizer was dependent on the temperature in the reactor.

• 대한환경공학회지
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• 제35권4호
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• pp.294-300
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• 2013

혐기성 암모늄 산화공정 전처리로써 적절한 $NO_2{^-}-N/NH_4{^+}-N$ 반응비율에 맞는 유출수를 생성하기 위한 연구실 규모의 연속 회분식 반응기 시스템을 적용하였다. 부분아질산화 적용에 있어서 운전인자들을 이용하여 AOB를 활성화하고, 동시에 NOB를 억제하는 다양한 전략이 있다. 하지만 적용된 인자들은 명확히 정의되지 않고 아질산 축적에 있어서 극복할 점이 있다. 본 연구의 목적은 부분아질산화의 주 인자를 조사하여 안정적인 공정을 구축하는데 있다. 부분아질산화 시스템을 구축하기 위하여 우세적인 인자인 온도, 중탄산알칼리도, pH를 평가하고자 한다. 실험의 결과로써 알맞은 알칼리도 비가 $35^{\circ}C$와 상온 두가지 온도범위에 안정적인 50% 부분아질산화가 이루어졌다. 이는 질산화시 필요한 알칼리도를 50% 아질산화에 맞추어 주입하여 질산화과정을 억제하는 것이다. 알칼리도 비는 pH 조절없이 50% 부분아질산화의 전략으로 제안한다. 유출수의 $NO_2{^-}-N/NH_4{^+}-N$ 비가 거의 100%에 다다랐을 때 중탄산알칼리도는 각각 6.8, 6.7이 되었다. PCR-DGGE의 미생물 분석 결과 암모늄산화균이 지배적인 질산화균임을 알 수 있었으며 NOB는 억제되어 활성을 잃은 것으로 사료된다.