• 한국환경과학회지
• /
• 제1권1호
• /
• pp.11-17
• /
• 1992

The treatment performances of anaerobic-aerobic activated sludge Process were investigated under various operation conditions. The treatment system proposed in this study gave a relatively stable performance against hourly change of the flow rate and showed a satisfactory removal efficiency of nitrogen and phosphorus compounds under experimental conditions. The average removal efficiency of total nitrogen gradually decreased as the influent total nitrogen concentration was increased. High C/N ratio of the wastewater was required for the complete removal of nitrogen. Glucose as a carbon source was more efficient than starch and the removal ability for all components become hither with the increase of the fraction of glucose.

• 한국물환경학회지
• /
• 제23권5호
• /
• pp.689-696
• /
• 2007

Kinetic analysis was important to develope the biological nutrient removal process effectively. In this research, anoxic-anaerobic-aerobic system was operated to investigate kinetic behavior on the nutrient removal reaction. Nitrification and denitrification were important microbiological reactions of nitrogen. The kinetics of organic removal and nitrification reaction have been investigated based on a Monod-type expression involving two growth limiting substrates : TKN for nitrification and COD for organic removal reaction. The kinetic constans and yield coefficients were evaluated for both these reactions. Experiments were conducted to determine the biological kinetic coefficients and the removal efficiencies of COD and TKN at five different MLSS concentrations of 5000, 4200, 3300, 2600, and 1900 mg/L for synthetic wastewater. Mathematical equations were presented to permit complete evaluation of the this system. Kinetic behaviors for the organic removal and nitrification reaction were examined by the determined kinetic coefficient and the assumed operation condition and the predicted model formulae using kinetic approach. The conclusions derived from this experimental research were as follows : 1. Biological kinetic coefficients were Y=0.563, $k_d=0.054(day^{-1})$, $K_S=49.16(mg/L)$, $k=2.045(day^{-1})$ for the removal of COD and $Y_N=0.024$, $k_{dN}=0.0063(day^{-1})$, $K_{SN}=3.21(mg/L)$, $k_N=31.4(day^{-1})$ for the removal of TKN respectively. 2. The predicted kinetic model formulae could determine the predicted concentration of the activated sludge and nitrifier, investigate the distribution rate of input carbon and nitrogen in relation to the solid retention time (SRT).

• 한국막학회:학술대회논문집
• /
• 한국막학회 1993년도 춘계 총회 및 학술발표회
• /
• pp.41-41
• /
• 1993

Recently, the advanced membrane separation technology has even been applied to the post treatment to biological process of wastewater treatment, since the efficiency of biological treatment significantly depends on maintaining a high biomass concentration in the bioreator. Particularly, anaerobic microbes in the biological system have slower growth rates than aerobic microbes and thus it takes a long hydaulic retention time(HRT) to prevent biomass washout in the completely mixed anaerobic digester. The anaerobic sludge also has poor settleability owing to its diffusible and somewhat filamentous nature. Moreover, the residual gasification and consequent sludge rise in the clarifier compartment become a considerable problem, which proves that complete separation of biological solids is difficult.

• 한국물환경학회지
• /
• 제23권6호
• /
• pp.906-912
• /
• 2007

A lab-scale thermophilic aerobic digestion (TAD) system was operated at $64^{\circ}C$ with mixed primary and secondary sludges taken from a large wastewater treatment plant. The semi-continuously operated reactor at HRTs of 1, 3 and 6 days indicated that longer HRT could stabilize sludge organics and solids comparable to anaerobic digestion. It has been found that reduced HRT of 3 and 1 day produced the effluent with highly biodegradable soluble organics, indicating the possibility of energy recovery in TAD. No proof of biological nitrification was observed at thermophilic operating temperature of $64^{\circ}C$, while nitrogen removal seemed due to nitrogen exertion during the aerobic thermophilic cell synthesis as well as ammonia stripping.

• 상하수도학회지
• /
• 제28권4호
• /
• pp.411-417
• /
• 2014

The performance of the new aerobic digestion system combined with inorganic sludge separation unit and sludge solubilization unit, CaviTec II, is evaluated. Anaerobic digester effluent sludge is used for feed sludge of CaviTec II system. By addition of CaviTec II, the amount of cake generated is reduced by 27%, and the soluble nitrogen is reduced by 92%.

• 한국축산시설환경학회지
• /
• 제11권2호
• /
• pp.97-102
• /
• 2005

Anaerobic decomposition is one of the most common processes in nature and has been extensively used in waste and wastewater treatment for several centuries. New applications and system modifications continue to be adapted making the process either more effective, less expensive, or suited to the particular waste in question and the operation to which it is to be applied. Animal manure is a highly biodegradable organic material and will naturally undergo anaerobic fermentation, resulting in release of noxious odors, such as in manure storage pits. Depending on the presence or absence of oxygen in the manure, biological treatment process may be either aerobic or anaerobic. Under anaerobic conditions, bacteria carry on fermentative metabolisms to break down the complex organic substances into simpler organic acids and then convert them to ultimately formed methane and carbon dioxide. Anaerobic biological systems for animal manure treatment include anaerobic lagoons and anaerobic digesters. Methane and carbon dioxide are the principal end products of controlled anaerobic digestion. These two gases are collectively called biogas. The biogas contains $60\~70\%$ methane and can be used directly as a fuel for heating or electrical power generation. Trace amounts of ammonia and hydrogen sulfide ($100\~300\;ppm$) are always present in the biogas stream. Anaerobic lagoons have found widespread application in the treatment of animal manure because of their low initial costs, ease of operation and convenience of loading by gravity flow from the animal buildings. The main disadvantage is the release of odors from the open surfaces of the lagoons, especially during the spring warm-up or if the lagoons are overloaded. However, if the lagoons are covered and gases are collected, the odor problems can be solved and the methane collected can be used as a fuel. Anaerobic digesters are air-tight, enclosed vessels and are used to digest manure in a well-controlled environment, thus resulting in higher digestion rates and smaller space requirements than anaerobic lagoons. Anaerobic digesters are usually heated and mixed to maximize treatment efficiency and biogas production. The objective of this work was to review a current anaerobic biological treatment of animal manure for effective new technologies in the future.

• 한국물환경학회지
• /
• 제21권5호
• /
• pp.490-495
• /
• 2005

Since there are very limited numbers of thermophilic anaerobic digesters being operated, it is often difficult to start up a new one using sludge from an existing reactor as a seed. However, for obvious reasons it seems few attempts have been made to compare the start-up performance of thermophilic anaerobic digestion using different sources of seed sludges. The purpose of this study was to evaluate the start-up performance of anaerobic digestion using aerobic Waste Activated Sludge (WAS) from a plant and mesophilic Anaerobic Digested Sludge (ADS) as the seed source at both mesophilic ($35^{\circ}C$) and thermophilic ($55^{\circ}C$) temperatures. In this study, two experiments were conducted. First, thermophilic anaerobic reactors were seeded with WAS (VSS = 4,400 mg/L) and ADS (VSS = 14,500 mg/L) to investigate start-up performance with a feed of acetate as well as propionate. The results show that WAS started to produce $CH_4$ soon after acetate feeding without a lag time, while ADS had a lag time of 10 days. When the feed was changed to propionate, WAS removed propionate down to below the detection limit of 10 mg/L, while ADS removed little propionate and produced little $CH_4$. Second, in order to further compare the methanogenic activity of WAS and ADS, both mesophilic and thermophilic reactors were operated. WAS acclimated to anaerobic conditions shortly and after acclimating it produced more $CH_4$ than ADS. WAS at mesophilic temperature biodegraded acetate at the same rate as for thermophilic. However WAS at mesophilic temperature biodegraded propionate at a much faster rate than at thermophilic. WAS as the seed source of anaerobic digestion resulted in much better performance than ADS at both mesophilic and thermophilic temperatures for both acetate and propionate metabolism.

• 자원리싸이클링
• /
• 제9권4호
• /
• pp.56-62
• /
• 2000

본 연구에서는 하.폐수 처리를 효과적으로 할 수 있도록 각종 비금속 광물들을 혼합하여 부착성 및 토양 미생물의 활동을 촉진시킬 수 있게 광물 소결체를 이용한 합병정화조를 도입하여 주택용 소규모의 생활 하수를 발생원에서 바로 처리하기 위하여 단독주택 2가구를 대상으로 소규모형 무산소-호기 공정 합병정화조 실험 장치를 설치하여 실험하였다. 그 결과 COD.BOD의 방류수는 10mg/l 전후로 나타났고 총질소 (T-N)는 60~70% 정도까지 제거시킴으로 인해 외부에서 탄소원을 첨가하지 않고도 탈질을 할 수 있음을 확인 할 수 있었다. 또한 춤인(T-P)은 80%이상의 제거 효율을 나타내어 생물학적 처리 가능성을 확인할 수 있었다.

• 한국물환경학회지
• /
• 제29권6호
• /
• pp.782-789
• /
• 2013

Enhanced biological phosphorus removal (EBPR) behavior and microbial characteristics in the anaerobic-aerobic SBR (PAO SBR) and the anaerobic-anoxic SBR (DPAO SBR) were examined in this research. For 392 days of operation, both SBRs have exhibited a good EBPR (or denitrifying EBPR) performance. $P_{release}/P_{influent}$ ratio was highest in both reactors after the stabilization, while the efficiency of phosphorus removal was decreased since the sludge granulation has been visually observed within the reactor. The comparative analysis of Pyrosequencing-based microbial population between PAO and DPAO sludges showed indirectly that Dechloromonas spp. could utilize $O_2$ and $NO_3{^-}-N$ as an electron acceptor and Accumulibacter phosphatis use only $O_2$ in EBPR system. Also, we concluded that Thauera spp. as a denitrifier contribute significantly to the anoxic phosphorus removal in the DPAO system.

• 유기물자원화
• /
• 제21권3호
• /
• pp.64-73
• /
• 2013

가축분뇨 처리시스템에 대한 환경영향을 분석하기 위하여 전과정 평가방법을 적용하였다. 전과정평가의 첫 번째 부분은 사용될 분석 항목을 구성하는 것으로, 가축분뇨 처리시스템에 대한 유입 및 배출에 대한 항목이다. 전과정 영향평가를 위한 다음 단계로서 전체 환경부하를 최종적으로 하나의 지수로 통합하기 위하여, 특정 항목에 대한 자료를 취합하고 분석하는 것이다. 전과정 영향평가를 위해, Eco-indicator 95 방법은 체계화 되었으며, 규칙적으로 적용된 영향평가 방법이기 때문에 선택하였다. 전과정 영향 분석을 위한 실례로서 호기 및 혐기소화 시스템과 같은 두 종류의 돈분 처리시스템을 선정하였다. 돈 분뇨 처리시스템에 대한 농업환경영향을 평가한 항목을 확립하였고, 혐기소화시스템에서는 전 인산 배출이 높았으며, 호기소화시스템에서는 이산화탄소 배출이 높은 것으로 관측되었다. 돈분 1ton을 처리하는데 관련된 돈분처리시스템에 대한 환경영향 평가에서 Eco-indicator 수치에 따르면, 호기소화 시스템에 있어 지구온난화 및 토양산성화에서 음의 지수를 보인 반면 혐기소화시스템은 수계 부영양화 부분에서 비교적 높은 양의 지수를 보였다.