• 미생물학회지
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• 제6권4호
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• pp.131-140
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• 1968

The soil of the reclaimed tidal land, located in Chogi-ri, Is. Kanghwa, Korea was used in this experiment. The experimented soil samples were collected from 18 sites with its time elapsed after the shore-protection works, soil-depth and the vegetation of saline plants, and at each site samplings were conducted monthly from March through October, 1968, for the purposes of examining the changes of microbial populations for the microbes such as bacteria, actinomycetes and fungi, by using the dilution plate method. The numbers of the microbes in these soils generally showed lower levels comparing with those of other soils. The more time elapsed after the reclamation, the higher numbers of the microbes inhibited the soils. Higher populations were there in the surface soils than in the lower part of the area. The surface soils included comparatively better conditions in aeration and contents of organic matter than in the lower part, and this fact was. same as in general soils. However, not so was this in the case of March, April and October due to the higher soil temperatures in the lows. At the experimental sites where the halophytes such as Salicorniu were grown vigourously, the more densly the plants grew, the higher populations of actinomycetes and fungi were, but not in the case of bacterial population. This means, in this soil with dense Salicornia, it is difficult to obtain good-natured soils in short time without a higher population of bacteria. For the rapid utilization of the land soil, in this view of point, the methods increasing the number of bacteria in the soil are needed as well as the cultivation and harvesting Salicorniu which indicated in the privious paper(Hong, et al., 1969a). According to the results of this experiment, the changes of soil-microbial populations in the reclaimed tidal land soil containing high salinity depend deeply upon the interrelations of many environmental factors such as soil-salinity, soil-components and contents, concentration of organic matters, pH, aeration, and air and soil temperatures, as in the general soils.

• 한국토양비료학회지
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• 제40권2호
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• pp.156-163
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• 2007

본 연구는 혼합유기질비료를 액비화할 때 액비화 효율을 증진시키기 위하여 폭기시간과 유기질비료 농도에 따른 무기성분의 특성변화를 조사하였다. 혼합 유기질비료는 참깻묵, 쌀겨, 어분, 혈분 등의 유기질 재료와 일라이트, 패화석 등으로 이루어져 있으며 약 2개월간의 발효과정을 거쳤고 N, $P_2O_5$, $K_2O$ 및 유기물함량은 각각 $23.0g\;kg^{-1}$, $17.0g\;kg^{-1}$, $23.9g\;kg^{-1}$, $290g\;kg^{-1}$이었다. 폭기시간은 일 2시간, 8시간, 연속 폭기 및 무폭기의 처리를 두었으며 물량에 대한 유기질비료 농도는 10%로 하였다. 유기질비료 농도에 따른 특성변화는 전체 물 함량에 대한 유기질비료 농도를 5%, 10% 및 20%로 하고 일 2시간씩 폭기를 하였다. 액비제조 기간이 경과함에 따라 폭기시간에 관계없이 pH, EC 및 $NH_4-N$ 농도는 증가하였다. 일 2시간 폭기한 처리구에서 액비제조 10일 후의 N, $P_2O_5$ 및 $K_2O$ 농도는 각각 $646mg\;kg^{-1}$, $68.1mg\;kg^{-1}$, $453mg\;kg^{-1}$으로 침출률은 각각 27.6%, 4.0% 및 18.9%이었으며 일 8시간 폭기 및 연속폭기조와 유의적인 차이가 없었다. 연속폭기조에서 호기성 세균, 포자형성 세균 및 사상균의 생균수가 다른 처리구보다 많았다. 물에 대한 유기질비료의 농도를 증가시키면 EC, $NH_4-N$ 및 무기성분 함량은 증가하였으나 유기질비료의 침출률은 감소하였다. 액비제조 10일 후 유기질비료 20% 처리구의 N, $P_2O_5$ 및 $K_2O$ 농도는 각각 $1,140mg\;kg^{-1}$, $35.4mg\;kg^{-1}$, $544mg\;kg^{-1}$이었고 침출률은 각각 24.8%, 2.4% 및 13.6%이었다. 유기질비료 농도의 증가는 포자형성 세균과 Pseudomonas spp. 균의 생균수를 증가시켰다.

• 한국환경과학회지
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• 제12권4호
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• pp.427-437
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• 2003

An evaluation of the application of SBR and biofilm en small sewerage system was conducted. A newly developed small sewerage system, using SBR, was successfully applied to the nutrient treatment using municipal wastewater. The system was consisted of 6 compartments. Two systems, with SBR (A type) or without SBR (B type), were compared by several parameters (COD, SS, T-N, NH$_4$$\^$+/-N, NO$_3$$\^$-/-N, NO$_2$$\^$ -/-N, alkalinity, pH, DO) in all experimental periods. Also, the time variation of several parameters (DO, pH, NH$_4$$\^$+/-N, NO$_3$$\^$-/-N NO$_2$$\^$-/-N) was examined in a SBR applied sewerage system. T-N removal efficiency of B type Was higher than that Of A type by the effect of nitrification and denitrification even though the COD removal efficiencies were similar. In aeration stage, the pH was decreased from 6.4 to 6.3 within 1 h and increased to 6.65 at the end of aerobic stage, and pH was decreased to 6.2 in non-aeration stage, and these phenomena were explained. The effects of nitrification and denitrification were compared in A type and B type sewerage system, and the typical nitrification and denitrification were observed in B type sewerage system.

• 상하수도학회지
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• 제19권5호
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• pp.537-546
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• 2005

This study was carried out to evaluate EPS and SMP variation of sludge and effluent in nitrification and denitrification process with zeolite addition, a possible reduction of effluent DOC by URC(Ultra Rapid Coagulation) process. As a biological wastewater treatment result, EPS formation of both aeration and anoxic sludges are not affect by SRT variation. However, EPS concentration of sludges is higher in aeration tank than in anoxic tank by 6~8 mg EPS/ g VSS. Linear relationship between SMP to DOC indicates that SMP of bulk solution contributes to most of the biological treatment effluent DOC. DOC and turbidity removal efficiency was more improved with URC process than in a conventional coagulation. For pretreatment of UF filtration DOC removal was advanced by URC process than only UF filtration.

• Environmental Engineering Research
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• 제14권4호
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• pp.238-242
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• 2009

This study investigated the effects of organic loading rates on simultaneous carbon and nitrogen removal in an innovative fixed-film aerobic bioreactor. The fixed-film bioreactor (FFB) was composed of a two-compartment aeration tank, in which a synthetic filamentous carrier was submerged as biofilm support media, and a settling tank which polyvinylidene media (Saran) was used as settling aid for suspended solids. Three different organic loading rates, ranging from 0.92-2.02 kg chemical oxygen demand/$m^3$/day were applied by varying hydraulic retention time (HRT). The total soluble organic carbon removal efficiencies were in the range of 90-97%. The removal efficiency of ammonia was found to be in the range of 70-84%. Total nitrogen removal efficiency was found to be in the range of 40-45%, which indicates that denitrification reactions occurred simultaneously in the attached biofilm on the fibrous media in the aeration tank. The settling performance of suspended solids was significantly improved due to the presence of Saran media in the settling compartment, even for a short HRT. The fixed-film aerobic bioreactor used in this study demonstrated efficient treatment efficiency even at higher organic loading rates and at short HRTs.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 추계학술대회 초록집
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• pp.175.1-175.1
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• 2011

A rotating activated bacillus contactor (RABC) process with a series of aerobic reactors was tested in pilot scale to treat digested liquid from an anaerobic digester treating swine wastewater and sewage sludge. The influent (digested liquid) for the RABC process showed C/N ratios less than 2 as a typical feature of effluent from anaerobic digesters. The pilot process, which consists of three 3 RABC reactors, four aerobic tanks and a sedimentation tank, was operated for 210 days with a hydraulic retention time of 20 days without pH and temperature control. Since the Bacillus-enriched aerobic reactors shows high efficiencies of nitrogen removal at low DO levels less than 1.0 mg/L, they were operated at reduced aeration intensities. With relatively low concentrations of organics in comparison with nitrogen concentrations, the RABC process tested in this study showed stable and high nitrogen and organics removal efficiencies over 80%. The nitrogen removal process tested in this study was proven to be an effective and operation-cost saving (lower aeration) method to remove nitrogen without adding external carbon sources to meet the optimum C/N ratio.

• 한국식품영양학회지
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• 제11권6호
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• pp.606-611
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• 1998

For waste recyle, we were investigated on Gardenia blue color production using Gardenia by-product by Bacillus subtilits. Optimum conditions for producing blue pigment were found to be 30$^{\circ}C$, initial pH 6.5, glucose as a carbon source 3% and yeast extract as a nitrogen source 0.5%, respectively. Optimum conditions for fermentor culture were agitation speed 400rpm, aeration 2 vvm and inoculum 5%. The optimum perculture time for inoculum was 20 hrs for blue pigment production.

• 한국수산과학회지
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• 제33권3호
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• pp.205-212
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• 2000

공기 구동식, 고속 폭기식 및 벤튜리식 포말분리 장치를 동일한 용량으로 제작하여 양어장 순환수 중의 단백질,총 부유 고형물 및 탁도를 제거하는데 있어 각 포말 분리장치의 운전 특성을 알아보고자 하였다. 공기구동식 포말분리기의 유략감소가 거의 없었으나 벤튜리식 포말분리기는 $66.1{\%}$정도의 유량감소가 발생하였으며 고속 폭기식 포말분리기는 $77.2{\%}$의 유량감소가 발생하였다. 공기 구동식, 고속 폭기식 및 벤튜리식 포말분리 장치의 단백질 제거속도는 수력학적 체류시간이 증가함에 따라 지수적으로 감소 하였다. 0.32 분 이상의 수력학적 체류시간에서는 공기 구동식 포말분리장치의 제거속도와 제거율이 가장 높게 나타났으며 그 이하의 수력학적 체류시간에 대해서는 고속 폭기식 포말분리 장치의 제거속도와 제거율이 가장 높은 것으로 나타났다. 수력학적 체류시간의 변화에 따른 총 부유 고형물과 탁도의 제거속도와 제거율의 변화는 단백질 제거속도 및 제거율의 변화와 거의 비슷하였으며 벤튜리식 포말분리기는 짧은 수력학적 체류시간에서는 총 부유고형물의 제거 효율이 다른 두 포말분리기에 비해 떨어지는 것으로 나타났다. 탁도의 제거는 공기 구동식 포말 분리기가 가장 우수한 것으로 나타났다.

• 유기물자원화
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• 제11권1호
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• pp.132-137
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• 2003

본 연구는 생물학적처리공정인 SBR에서 아세트산의 주입시간에 따른 질소와 인의 제거특성을 알아보기 위해서 수행되었으며, 실험기간동안 사용된 폐수는 유기물에 비해 질고농도가 상대적으로 높은 특성을 갖는 양돈폐수이었다. 아세트산의 주입시간에 따른 실험에서 Run 1은 무산소기간에 아세트산을 주입하지 않았고, Run 2는 무산소기간 15시간동안 간헐적으로 아세트산을 주입하였다. 그리고 Run 3은 폐수유입의 종료시로부터 3시간의 무산소기간동안에 간헐적으로 주입하였다. 그리고 폐수의 유입시간은 모든 조건에서 20시간으로 하였다. 본 실험에서 유기물과 질소에 있어서 가장 제거효율이 높게 나타난 조건은 Run2(교반/폭기 시간비 : 16.5/5.5, 아세트산주입시간 15시간)이었고, T-P에 있어서는 Run 3조건(교반/폭기 시간비 : 16.5/5.5, 아세트산주입시간 : 3시간)에서 가장 높은 효율을 나타내었으며 각각의 제거효율은 $BOD_5$ 96.1%, $COD_{Mn}$ 87.7%, $COD_{Cr}$ 90.6%, T-N 86.6% 그리고 T-P는 84.5%로 나타내었다.

• 한국환경과학회지
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• 제13권3호
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• pp.245-250
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• 2004

The SBR(Sequencing Batch Reactor) process is ideally suited to treat high loading wastewater due to its high dilution rate. SBR operates by a cycle of periods consisting of filling, reacting, settling, decanting and idling. The react phases such as aeration or non-aeration, organic oxidation, nitrification, denitrification and other bio-logical reactions can be achieved in a reactor. Although the whole reactions can be achieved in a SBR with time distributing, it is hard to manage the SBR as a normal condition without recognizing a present state. The present state can be observed with nutrient sensors such as ${NH_{4}}^{+}-N$, ${NO_{2}}^{-}-N$, ${NO_{3}}^{-}-N} and ${PO_{4}}^{ 3-}-P.$ However, there is still a disadvantage to use the nutrient sensors because of their high expense and inconvenience to manage. Therefore, it is very useful to use common on-line sensors such as DO, ORP and pH, which are less expensive and more convient. Moreover, the present states and unexpected changes of SBR might be predicted by using of them. This study was conducted to get basic materials for making an inference of SBR process from ORP(oxidation reduction potential) of synthetic wastewater. The profiles of ORP, DO, and pH were under normal nitrification and denitrification were obtained to compare abnormal condition. And also, nitrite and nitrate accumulation were investigated during reaction of SBR. The bending point on ORP profile was not entirely in the low COD/NOx ratio condition. In this case, NOx was not entirely removed, and minimum ORP value was presented over -300mV. Under suitable COD/NOx ratio which complete denitrification was achieved, ORP bending point was observed and minimum ORP value was under -300m V. Under high COD/NOx ratio, ORP bending point was not detected at the first subcycle because of the fast denitrification and minimum ORP value was under -300mV at the time.