• 지질공학
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• 제23권2호
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• pp.95-104
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• 2013

농업용 저수지의 수질 개선을 위한 효율적 관리 방안은 본 연구에서 제시되었다. 홍동 저수지는 저수지 유역 내에 농경지, 산림지역, 주거지역, 그리고 축산지역 등을 포함하고 있다. 수질 환경을 복원시키기 위해 우선 저수지 내 퇴적물의 오염도를 조사되었고 저수지내 퇴적토의 잠재적인 영양염류인 분석한 결과 총질소(T-N)은 $1.06g/m^2-d{\sim}3.67g/m^2-d$로 분포를 보이고 총인(T-P)는 $0.52 g/m^2-d{\sim}1.12g/m^2-d$로 측정되었다. 또한 퇴적토 준설 시 용출 특성 분석을 위해 72시간동안 20 혐기성 조건으로 시험을 진행되었다. 총인(T-P)와 (인산염인) $PO_4$-P의 농도는 시간에 따라 비교적 일정하게 용출되는 특성이 나타났으며 총질소(T-P)의 경우에 아질산성 질소($NO_2$-N)와 질산성 질소($NO_3$-N)의 탈질산화로 인하여 그농도가 불규칙적으로 용출되는 특성을 보였다. 특히, 암모니아인 경우는 컬럼 내부의 혐기성 조건으로 형성된 낮은 pH로 인하여 질소($N_2$)와 함께 용출 양은 극히 미량으로 측정되었다.

• 한국가금학회지
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• 제35권2호
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• pp.115-121
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• 2008

본 시험은 microbial phytase을 첨가하여 산란계에 급여시 산란율, 계란 품질, 인 이용율 및 영양소 소화율에 미치는 영향을 조사하기 위하여 수행하였다. 32주령 Hy-Line Brown 갈색계 120수를 공시하여, 4주간 사양시험을 실시하였다. 시험 설계는 CON(control), LP(low phosphorus diet), NP(low phosphorus diet + 0.03% normal microbial phytase) 및 CP(low phosphorus diet + 0.03% coated microbial phytase)로 4개 처리를 하여 처리당 5반복, 반복당 6수씩 완전 임의 배치하였다. 전체 기간 동안 산란율은 CON과 CP 처리구가 LP 처리구보다 높게 나타났다(P<0.05). 난각 강도와 난각 두께는 LP 처리구에 비해 CON, CP 및 NP 처리구가 높게 나타났다(P<0.05). 난황색과 haugh unit에서는 CON, CP 및 NP 처리구가 LP 처리구보다 높게 나타났다(P<0.05). 혈액내 칼슘과 인 농도는 CP 처리구가 LP 처리구에 비해 높게 나타났다(P<0.05). 건물 소화율과 질소 소화율에서는 CP 처리구가 CON, LP 및 NP 처리구에 비하여 유의적으로 증가하였다(P<0.05). 회분소화율은 CON, CP 및 NP 처리구가 LP 처리구에 비해 증가하였다(P<0.05). 칼슘 소화율과 인 소화율에서는 CP와 NP 처리구가 CON과 LP 처리구에 비해 높게 나타났다(P<0.05). 칼슘 흡수량은 CON, CP 및 NP 처리구가 LP 처리구보다 유의적으로 높게 나타났다(P<0.05). 인 흡수량은 CP와 NP 처리구가 CON과 LP 처리구와 비교하여 유의적으로 높게 나타내었다(P<0.05). 질소와 칼슘 배출량은 CON, NP 및 CP 처리구가 LP 처리구에 비해 유의적으로 낮게 나타냈다(P<0.05). 인 배출량은 LP, NP 및 CP 처리구가 CON 처리구에 비해 유의적으로 낮게 나타내었다(P<0.05). 결론적으로, 산란계에 있어 코팅된 microbial phytase의 첨가는 산란율, 계란 품질, 혈액 내 칼슘과 무기태 인, 영양소 소화율과 칼슘 및 인 흡수량을 증진시키며, 질소와 칼슘 배출량을 감소시키는 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권5호
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• pp.698-701
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• 2000

To prevent surface and underground water pollution, wastewater treatment is essential. Four bench-scale activated sludge units (10 L operational volumes) were operated at 5, 10 and $20^{\circ}C$ for evaluation of treatment efficiencies with typical wastewater from swine housing. The units were set for a 24-hour cycle. As compared to the conventional process, high removal efficiencies for organic substances, nitrogen and phosphorus in swine wastewater were obtained simultaneously with an intermittent aeration process (lAP). The NOx-N produced during an aeration period was immediately reduced to nitrogen gas (e.g. $N_2$ or $N_2O$) in the subsequent non-aeration periods, and nitrification in aeration periods occurred smoothly. Under these conditions, phosphorus removal occurred with the release of phosphorus during the non-aeration periods followed by the excess uptake of phosphorus in the activated sludge during aeration periods. It was confirmed that the lAP had a better ability to remove pollutants under both low temperatures and high nitrogen loading conditions than the ordinary method did. In addition to that, the total emission of $N_2O$ from lAP was reduced to approximately 1/50 of the conventional process for the same loading. By adopting an adequate aeration programme for individual swine wastewater treatment, this system will provide a promising means for nitrogen and phosphorus control without pH control or addition of methanol.

• Ecology and Resilient Infrastructure
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• 제10권3호
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• pp.85-96
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• 2023

국내 호소를 상류 저수지 (<0.3 psu), 하구 저수지 (0.3 - 2 psu), 기수성 석호 (>2 psu)로 분류하여 호소별 퇴적물 총질소 (T-N), 총인 (T-P) 농도의 차이를 일원분산분석 (ANOVA) 하였으며, 실험실 코어 배양법 (laboratory core incubation)을 이용해 송지호 (11.80 psu), 간월호 (0.73 psu), 장군 저수지 (0.08 psu)의 호기 (aerobic)와 무산소 (anoxic) 조건에서의 질소 및 인 용출량 (benthic nutrient flux)을 측정하였다. 국내 호소의 퇴적물 내 총질소와 총인 농도는 염분 농도가 다른 호소별로 유의한 차이가 있는 것으로 분석되었다 (p<0.05). 사후 검정 (post-hoc)을 통해 총질소의 경우 상류 저수지 (2,918 mg/kg)와 하구 저수지 (2,094 mg/kg)에서 유의한 차이를 확인하였고 (p<0.001), 총인의 경우 상류 저수지 (789 mg/kg)와 기수성 석호 (533 mg/kg)가 유의한 차이를 보였다 (p<0.01). 실험을 통해 산정된 NH₄⁺-N의 용출량은 간월호에서 가장 높게 나타났으며, 폐쇄성 수역인 물리적인 특성과 염분으로 인한 질산화의 저해 등에 의한 것으로 판단된다. NO₃^--N의 용출량은 호기 조건에서 염분이 높은 호소일수록 낮게 나타났으나 무산소 조건에서는 염분이 높은 호소일수록 용출량이 높게 관측되었고, 이는 염분이 질산화 및 탈질이 억제되었기 때문이다. PO₄^3--P의 경우 송지호, 간월호, 장군 저수지 순으로 용출량이 높게 나타나, 염분이 음이온 흡착 경쟁 등을 통해 인산염의 용출을 촉진시키는 것으로 조사되었다. 퇴적물의 용출량 산출 시 미생물 군집, 성장률, 산화, 환원, 영양염류의 결합 형태 등의 요인이 염분에 의해 영향을 받으므로 염분화 된 호소의 퇴적물 용출 조사 시 염분에 의한 영향을 고려해야 할 것으로 사료된다.

• 한국물환경학회지
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• 제33권6호
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• pp.722-727
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• 2017

Livestock manure is known to be the main cause of non-point pollution in agricultural areas. The pollutant reduction ratio of livestock manure recycling to fertilizers was measured in order to analyze the effect on the water quality of the Total Maximum Daily Load (TMDL) system in Korea. The reduction ratio has been applied by theoretical consideration without a survey, and there is no value for Total Organic Carbon (TOC) newly introducing any organic items. The reduction ratio of each pollutant from this study was revealed as follows: TOC, BOD, T-N and T-P were 0.34, 0.60, 0.37, and 0.42 for individual farm and 0.38, 0.61, 0.45 and 0.44 for entrustment facilities, respectively. The reduction ratio of individual farm was surveyed as TOC 0.63, BOD 0.62, T-N 0.42 and T-P 0.32 for liquid fertilizer, and TOC 0.30, BOD 0.64, T-N 0.40 and T-P 0.48 for compost. The total reduction ratio was derived by multiplying the ratio for liquid fertilizer and compost by the respective load. Compared to the pollutant reduction ratio of the individual farm with entrustment facilities marking the higher in liquid fertilizer and the lower in compost. Through this study, we found the difference of pollutant reduction ratio between a livestock manure recycling process and facilities. Although phosphorus is known as a preservative matter, the treatment efficiency of T-P is analyzed to decrease by chemical precipitation.

• 상하수도학회지
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• 제35권5호
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• pp.323-334
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• 2021

Pilot-scale coagulation and sedimentation processes were operated to investigate the T-P (Total phosphorus) removal efficiency. A multiple regression model was also derived to predict the water quality improvement effect with river water characteristics. The inflow rates for the pilot-scale facility were 157-576 m³/day, and the coagulant doses were in the range of 13.7-58.5 mg/L (average 38.9 mg/L) for PAC (Poly alum chloride) and 16.5-62.1 mg/L (average 36.0 mg/L) for alum. The results found that the influent BOD (Biochemical oxygen demand) and T-P concentrations were 4.9 mg/L and 0.115 mg/L, and the removal efficiencies were 52.7% and 59.4%, respectively. T-P removal efficiencies on wet weather days were higher by 10% than dry weather days because influent solids influenced T-P's coagulation process. The pH of river water was 6.9-7.8, and the average pH was 7.3. Although the pH variation was not significant, the trend showed that the treatment efficiency of T-P and PO₄-P removal increased. Thus, the pH range considered in this study seems to be appropriate for the coagulation process, which is essential for phosphorous removal. The T-P removal efficiencies were 19.6-93.3% (average 59.2%) for PAC and 16.4-98.5%(average 55.9%) for alum; thus, both coagulants showed similar results. Furthermore, the average coagulant doses were similar at 42.4 mg/L for PAC and 41.3 mg/L for alum. When the T-P concentration of the effluent was compared by the [Al]/[P] ratio, the phosphorus concentration of the treated water decreased with an increasing [Al]/[P] ratio, and the lowest T-P concentration range appeared at the [Al]/[P] ratio of 10-30. A seasonal multiple regression analysis equations were derived from the relationships between 10 independent and dependent variables (T-P concentration of effluent). This study could help lake water quality maintenance, reduce eutrophication, and improve direction settings for urban planning, especially plans related to developing waterfront cities.

• Asian-Australasian Journal of Animal Sciences
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• 제11권1호
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• pp.89-96
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• 1998

The experiment was conducted with 120 barrows weaned at 21 days of age to estimate their lysine requirement weaned at 21 days of age when other important amino acids were fortified to get optimal ratio to lysine. The treatments were 1.15% (control), 1.25%, 1.35%, 1.45%, 1.55%, 1.65% total lysine in the diet. Based on the growth performance total lysine requirement of 21-day old pigs appears to be 1.45%. The lowest digestibilities of dry matter and crude fat were found in pigs fed 1.15% total lysine diet and the highest were found in pigs fed 1.65% total lysine diet with no significant differences among treatments. Nitrogen digestibility increased as the total lysine level increased up to 1.35% (p < 0.05) and remained relatively constant beyond 1.35%. However, the best nitrogen digestibility was observed in pigs fed 1.45% total dietary lysine. Gross energy, crude ash and phosphorus digestibilities did not differ due to the increase in total lysine level. The amounts of excreted dry matter and nitrogen differed significantly by the increase in lysine level up to 1.35% (p < 0.05), while phosphorus excretion was not influenced by the lysine level. Dry matter and nitrogen excretion were reduced by 13.6% and 18.4%, respectively, when 1.45% lysine was offered to the pigs compared to the those fed on 1.15% lysine diet. The amino acid digestibilities increased as the total lysine level increased up to 1.45% (p < 0.05), and remained constant beyond 1.45%. The lysine requirement for the pigs weighing 6 to 14 kg seems to be higher than the previous estimates and in order to reduce pollutant excretion the accurate nutrient requirement should be set and applied to the animal.

• 상하수도학회지
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• 제27권6호
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• pp.779-785
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• 2013

This study investigated the applicability of a two step microfiltration(MF) and reverse osmosis(RO) membrane system for reuse of tunnel wastewater. In this two step process, the MF system first treated only micropollutants in tunnel wastewater such as suspended solids(SS) and heavy metals, achieving less than 0.2 NTU turbidity, less than 1.1 mg/L chemical oxygen demand($COD_{Mn}$) and less than 0.8 mg/L total manganese(Mn). The RO system then removed over 95 % of the remaining pollutnats and particles, resulting in less than 0.02 NTU turbidity, less than 0.5 mg/L chemical oxygen demand($COD_{Mn}$), less than 0.04 mg/L total nitrogen(T-N) and less than 0.01 mg/L total phosphorus(T-P). In particular, addition of an RO system could lead to markedly reduced high salt concentrations in tunnel wastewater, approaching almost zero. Thus, reclaimed water using the combined membrane system could satisfy current South Korean regulations concerning wastewater reuse(turbidity ${\leq}2.0$ NTU; T-N ${\leq}10mg/L$; T-P ${\leq}0.5mg/L$; Salinity ${\leq}250mg{\cdot}Cl/L$).

• 한국환경보건학회지
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• 제27권1호
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• pp.112-118
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• 2001

The aim of this study was to evaluate on the removal effect of total nitrogen and phosphorus in municipal wastewater with temperature change from 1$0^{\circ}C$ to 24$^{\circ}C$ in CNR(Cilia Nutrient Removal) process. CNR process is the process combining $A^2$/O process with cilium media of H2L company. The removal efficiencies for T-N were found to be 57.9% at 1$0^{\circ}C$ below, 53.7% at 10-2$0^{\circ}C$, 52.2%at 20-24$^{\circ}C$ and 44.4% over 24$^{\circ}C$ respectively. The removal efficiencies for T-P were 53.3% at 1$0^{\circ}C$ below, 59.1% at 10-2$0^{\circ}C$, 72.4% at 20-24$^{\circ}C$ and 50.0% over 24$^{\circ}C$ respectively. The specific nitrification rate (kg NH$_3$-N/kg MLSS.d) of Oxic basin was 0.088 and 0.053 at 1$0^{\circ}C$ below, 0.077 at 10-2$0^{\circ}C$, 0.097 at 20-24$^{\circ}C$ and 0.088 over 24$^{\circ}C$ respectively. The specific denitrification rate (kg NH$_3$-N/kg MLSS.d) in anaerobic and anoxic was 0.013, 0.008 respectively.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.747-752
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• 1999

The effects of nonpoint source pollutants from a small agricultural alluvial watershed on groundwater quality were investigated and analyzed in this study . Water quality factors of pH, electric conductivity(EC), total nitrogen(T-N), nitrate nitrogen(NO3-N), ammonium nitrate(NH4-N), and total phosphorus(T-P) concentrations were monitored at the watershed located in Shinbook-myon , Chunchon, Kangwon-Do, Korea for 2 years. Groundwater samples of about 2 liters from 7 to 20 farm wells were regulary collected and analyzed with respect to the water quality factors which were again anlayzed with respect to time and land uses of residential , agricultural , livestock feedlot, greenhouse, and natural areas.