• 한국환경농학회지
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• 제30권2호
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• pp.118-124
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• 2011

BACKGROUND: Development of water recycle technologies is important for human health and sustainable agriculture. However, few studies have been conducted to examine the purification methods or the water quality of reclaimed wastewater in Korea. METHODS AND RESULTS: In this study, the different wastewaters including reclaimed wastewater and waste nutrient solution (NS) were evaluated. The changes of water quality in reclaimed wastewater and NS were determined using ultraviolet (UV) treatment and sand filtration with charcoal. Our results showed that one of the most critical limitations of reusing wastewater was the presence of harmful pathogens that possibly cause human health risks. CONCLUSION(s): This study suggests that the application of UV treatment or combined with sand filtration on reclaimed wastewater and waste NS effectively removes the total coliform bacteria below the harmful or acceptable level. For future studies, a long-term field monitoring after applying reclaimed wastewater or NS is needed.

• 한국환경과학회지
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• 제26권1호
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• pp.109-118
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• 2017

This study was conducted to investigate the effects of intermittent plasma and electrolysis treatments on lettuce (Lactuca sativa var. oak-leaf.), nutrient solution components ($NO_3{^-}-N$, $NH_4{^+}-N$, $PO{_4}^{3-}-P$, $K^+$, $Ca^{2+}$ and $Mg^{2+}$) and environmental parameters (electrical conductivity, total dissolved solids and pH). The recirculating hydroponic cultivation system consisted of planting port, LED lamp, water reservoir and circulating pump. Nutrient solution was circulated in the following order: reservoir ${\rightarrow}$ filtration-plasma or filtration-electrolysis ${\rightarrow}$ planting port ${\rightarrow}$ reservoir. The results showed that nutrient solution components and environmental parameters were changed by plasma or electrolysis treatment. Lettuce growth was not affected by the intermittent plasma or electrolysis treatment with 30 minutes or 90 minutes, respectively. The roots of the lettuce was damaged by excessive plasma and electrolysis treatment. Electrolysis treatment had greater effect on than plasma treatment because of the accumulation of high levels of TRO (Total Residual Oxidants).

• 한국입자에어로졸학회지
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• 제6권4호
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• pp.185-192
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• 2010

This paper reports that the installation of a carbon fiber ionizer in front of an activated carbon fiber(ACF) filter enhanced the antibacterial efficiency. In addition, the effect of the ionizer on the filtration of bioaerosols is reported. Negative air ions from the ionizer were used as antibacterial agent. The test bacteria(Escherichia coli) were aerosolized using an atomizer and were deposited on the ACF filter media for 10 minutes. E. coli deposited on the filter were exposed to negative air ions for 0, 1, 5 and 10 minutes. Then they were separated from the ACF filter by shaking incubation with nutrient broth for 4 hours. The separated E. coli were spread on nutrient agar plates and incubated at $37^{\circ}C$ for 1~3 days. The antibacterial efficiency of E. coli was measured using a colony counting method. The antibacterial efficiencies of E. coli exposed to negative air ions for 1, 5 and 10 minutes were 14%, 48% and 71%, respectively. The filtration efficiency was evaluated by measuring the number concentration of bioaerosols at the upstream and downstream of the filter media. The increase of filtration efficiency by air ions was 14%, that is similar to the 17% filtration efficiency by none air ions. The ozone concentration was below the detection limit (under 0.01ppm) when the carbon fiber ionizers were on.

• 한국환경과학회지
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• 제23권6호
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• pp.1165-1173
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• 2014

For the field application of dielectric barrier discharge plasma reactor in nutrient solution culture, a filtration-DBD (dielectric barrier discharge) plasma reactor was investigated for the Ralstonia solanacearum which causes bacterial wilt in aquiculture. The filtration-DBD plasma reactor system of this study was consisted of filter, plasma reactor, reservoir. The DBD plasma reactor consisted of a quartz dielectric tube, discharge electrode (inner) and ground electrode (outer). The experimental results showed that the inactivation of R. solanacearum with filter media type in filter reactor ranked in the following order: anthracite > fiber ball > sand > ceramic ball > quartz ceramic. In filtration + plasma process, disinfection effect with the voltage was found to small. In disinfection time of 120 minutes, residual R. solanacearum concentration was 1.17 log (15 CFU/mL). When the continuous disinfection time was 120 minute, disinfection effect was thought to keep the four days. In sporadic operation mode of 30 minutes disinfection - 24 hours break, residual R. solanacearum concentration after five days was 0.3 log (2 CFU/mL). It is considered that most of R. solanacearum has been inactivated substantially.

• 한국습지학회지
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• 제8권2호
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• pp.45-51
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• 2006

우리나라 대부분의 하수처리장에서는 영양염류 및 MBAS의 제거를 위하여 생물학적 고도처리시설과 모래여과시설을 설치하여 운영하고 있다. 그러나 미처리된 영양염류 및 합성세제가 수계에 그대로 유입되어 하천에 사상성부착조류의 발생 및 하천의 자정작용을 방해하여 물에서의 이 취미 발생과 거품 때문에 미관상 불쾌하여 하수처리수를 도시하천유지용수로 재이용하는 G 하수처리장을 실험 대상으로 하여 모래여과시설에 대한 MBAS 제거효율을 파악하고자 본 연구를 실시하였다. 그 결과 모래여과를 이용한 MBAS의 최대 제거 효율은 24시간이 지난 후에 63% 정도로 나타났고 특히, 2시간 내지 4시간이 경과한 후의 MBAS 제거 효율도 30% 정도로 그 효과는 아주 적은 것으로 나타났다. 결론적으로 모래여과를 이용한 MBAS 제거는 여과지속시간이 장시간 소요되어 시설부지의 대규모화 등 경제성이 부족하고 제거 효율도 거의 기대에 미치지 못하여 앞으로 하수처리수를 하천유지용수로 재이용하는 하천에서는 MBAS 제거를 위해서는 모래여과시설보다는 다른 공법의 연구와 대책이 필요할 것으로 판단되었다.

• 농촌계획
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• 제24권2호
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• pp.21-29
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• 2018

Riparian management has become important as stream water quality as well as riparian ecosystem gain more public attentions. The objective of this study was to determine riparian widths based on the functions of nutrient removal and wildlife habitat protection and to apply for the Jinwee stream area as a preliminary case. Nitrogen and phosphorus filtration efficiencies were considered in water quality aspect, while the habitat radii of amphibian and reptiles were used for wildlife conservation purpose. In addition, observation of endangered species and human impact on wildlife disturbance in riparian area were also taken into account in determining riparian widths. The stream confluence zone was emphasized by doubling the riparian widths as the focal point for wildlife habitat conservation. As the results, three different levels of riparian widths were proposed depending on the major riparian functions and applied to the Jinwee stream section as the case study. The proposed method can be used to determine riparian width in other stream areas based on different functional focus, ie, water quality or riparian conservation purposes.

• 한국유기농업학회지
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• 제17권3호
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• pp.357-370
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• 2009

본 연구는 돈분뇨 여과 및 농축액비를 이용한 양액재배의 가능성을 검토하기 위하여 여과액비와 농축액비와 부산물, 양액 혼합처리가 토마토 생육에 미치는 영향을 검토하였다. 퇴비화 과정 중 과수분 상태에서 배출되는 퇴비단 여과액비와 막분리 처리과정에서 한외 여과막을 통과하고 역삼투막 처리에서 역류되어 나오는 돈슬러리 농축액비를 공시재료로 하였다. 본 연구는 질소함량을 기준으로 액비와 부산물, 양액의 혼합하는 처리구를 두어 전기전도도와 pH를 조정하여 토마토의 양액재배를 실시한 결과를 요약하면 다음과 같다. 1. 여과액비와 농축액비는 다량 및 미량원소를 함유하고 부유물질(SS)이 낮아 양액재배시 관배수의 막힘문제 없이 활용이 가능하였다. 여과, 농축액비는 인산, 칼슘, 마그네슘 함량이 낮고 칼륨이 높은 양분불균형를 나타내었다. 2. 여과액비는 원예연 표준양액 대비 총수량 91%, 상품수량 70%를 나타내어 여과액비 단독급액으로 토마토의 유기 수경재배 생산이 가능하였다. 3. 막처리 농축액비 100% 처리구는 토마토의 지상부의 생육이 지연되고 과중이 감소되어 화학양액 대비 40%의 수량을 나타내었다. 4. 퇴비단 여과액비+부산물, 농축액비+부산물 혼합처리구의 토마토 수량은 대조구 대비 각각 87, 76%를 나타내어 여과액비 단독시용구의 수량에 미치지 못하였다. 5. 질소기준으로 여과액비와 농축액비에 양액을 50% : 50% 비율로 혼합하여 균형처방 처리한 경우 표준양액 처리와 대등한 수량을 나타내었다. 결론적으로 토마토 양액재배에서 생육과 수량을 고려할 때 액비와 양액의 50 : 50 혼합 재배시 수량이 유지되어 가축분뇨 유래 유기액비에 의하여 화학양액를 50% 대체할 수 있을 것으로 판단된다.

• Journal of Applied Biological Chemistry
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• 제54권2호
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• pp.84-88
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• 2011

Edestin, a major hempseed storage protein from Cheungsam, was isolated to apparent homogeneity by acid precipitation and gel filtration chromatography. The native molecular weight of purified edestin was approximately 300 kDa by Sephacryl S-300 gel filtration. Upon adding 2-mercaptoethanol, the isolated edestin of 56.7 kDa on the non-reduced sodium dodecyl sulfate polyacrylamide gel was converted into subunits, suggesting that the protein might be composed of subunits linked by disulfide bond. Cheungsam edestin was rich in essential amino acids and it has 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity. The results suggest that Cheungsam edestin might be utilized as a superior antioxidative nutrient.

• 대한환경공학회지
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• 제22권5호
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• pp.895-905
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• 2000

본 연구는 여재가 모래와 무연탄인 복층 중력식 급속여과법으로 BNR(biological nutrient removal) 공정 유출수를 처리할 때 여과율의 변화에 따른 오염물질 제거효율 및 여층 깊이별 처리수질을 파악하기 위하여 수행되었다. Pilot scale의 4-stage BNR 공정 유출수를 200, 300 및 400 m/day의 여과율로 급속여과시킨 결과, 처리수는 2.6 NTU 이하의 탁도를 나타내어 우리나라의 중수도 제한수질인 5.0 NTU를 만족하였다. 여과율이 200, 300 및 400 m/day로 증가함에 따라 SS 제거효율은 각각 80.6, 75.4 및 68.9%로 감소하는 경향을 보였지만, 여과수는 모든 여과율에서 유입수의 수질변화에 큰 영향을 받지 않고 평균 1.3 mg/L의 SS 농도를 보였다. 생물학적 작용에 의하여 영양염류도 제거되었는데, 200, 300 및 400 m/day의 여과율에서 질산화효율이 각각 17.4, 18.8 및 14.3%, 그리고 탈질효율이 각각 32.3, 27.7 및 21.4%로, 질산화와 탈질이 동시에 일어났다. 여과주기의 후반기에는 여층 내의 DO가 결핍됨에 따라 인의 재용출이 일어남으로써 유출수의 T-P 농도가 유입수에 비하여 6.1~21.4% 증가하였다.

• Environmental Engineering Research
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• 제21권3호
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• pp.265-275
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• 2016

In this study, the microalga Neochloris oleoabundans was cultivated in a sustainable manner using diluted anaerobic digestate to produce biomass as a potential biofuel feedstock. Prior to microalgae cultivation, the anaerobic digestate was characterized and several pretreatment methods including hydrogen peroxide treatment, filtration, and supernatant extraction were investigated and their impact on the removal of suspended solids as well as other organic and inorganic matter was evaluated. It was found that the supernatant extraction was the most convenient pretreatment method and was used afterwards to prepare the nutrient media for microalgae cultivation. A bench-scale experiment was conducted using multiple dilutions of the supernatant and filtered anaerobic digestate in 16 mm round glass vials. The results indicated that the highest growth of the microalga N. oleoabundans was achieved with a total nitrogen concentration of 100 mg N/L in the 2.29% diluted supernatant in comparison to the filtered digestate and other dilutions.