• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.62-65
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• 2001

담수와 해수가 혼합되는 환경에서 퇴적 저니로부터의 오염 물질 용출률을 조사하였다. 축산폐수와 산업폐수의 영향을 받은 두 지점의 퇴적저니 시료에 대해 해수와 담수로 장기(약4주) 용출 시험을 행한 결과, 해수보다는 담수에서의 오염물질(영양염류 및 중금속) 용출률이 높은 것으로 조사되었는데, 이는 담수에서의 이온강도(ionic strength)가 상대적으로 낮아 오염성분의 포화농도가 높기 때문인 것으로 판단된다. 또한, 용존산소의 농도를 달리하여 시험한 결과 무산소 상태에서의 용출률이 호기성 상태에서 보다 높은 것으로 나타났으며, 그 원인이 생물학적인 것인지 화학적인 것인지는 밝혀지지 않았다. 시험결과를 종합해 볼 때 무산소 상태의 담수에서 오염물질의 용출이 극대화되며, 따라서 강어귀 등과 같이 유속이 작아져 오염물질의 침강은 잘되는 반면 오염물질의 해수에 의한 희석 효과는 적은 경우가 저니로 인한 수질 환경영향이 가장 클 것으로 예측된다.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.7
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• pp.665-675
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• 2010

The effects of chemical binders (ladle slag, ordinary portland cement (OPC), hydroxyapatite and calcium hydroxide) on the solidification/stabilization of heavy metals (Cd, Cu, Ni, Pb, Zn) in sewage sludge were evaluated by chemical leaching tests such as EDTA extraction, TCLP and sequential extraction. The results of EDTA extraction showed that heavy metal concentrations in sewage sludge were highly reduced after solidification/stabilization with slag, cement or calcium hydroxide. However, EDTA interrupted solidification/stabilization of heavy metals by hydroxyapatite. The TCLP-extracted heavy metal concentrations in sewage sludge after solidification/stabilization with chemical amendments were highly reduced. However, Cu concentration in the sewage sludge solidified/stabilized with slag, cement or calcium hydroxide increased because the pH of TCLP solution was higher than 7. Mixtures of sludge 1 : slag 0.2 : calcium hydroxide 0.1 (wt ratio) showed the least leachability in batch TCLP and EDTA extraction. The results of sequential extraction (SM&T, formaly BCR) indicated that the distribution of heavy metals changed from exchangable and carbonate fractions to strongly bound organic fraction. It was found that maximum leachate concentrations of Ba, Cd, Cr and Pb from sewage sludge amended with slag and calcium hydroxide were far below US EPA TCLP regulations.

• Korean Journal of Food Science and Technology
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• v.47 no.6
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• pp.725-732
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• 2015

This study was conducted to compare the physicochemical and sensory characteristics of beef-bone broths prepared under atmospheric pressure (BBAP) and overpressure (BBOP). Beef-bone was boiled in water (bone/water=1:2, w/w) for 1, 2, 4, 6, and 12 h under atmospheric pressure and overpressure ($121^{\circ}C$, 1.25 atm). The BBOP broth samples were found to contain significantly higher amounts of solid, crude protein, crude ash, collagen, and chondroitin sulfate than the BBAP broth samples for a given boiling time (p<0.05). In addition, the Ca and Mg contents in the BBAP samples were higher than those in the BBOP samples, whereas the P, Na, and K contents were higher in BBOP than BBAP. The L value of BBAP was also significantly higher than that of BBOP (p<0.05). Further, as the boiling time increased, turbidity increased in the BBAP samples. In the quantitative descriptive analysis, the BBOP samples exhibited stronger brownness, transparency, meaty off-odor, meaty off-flavor, and sulfuric odor than the BBAP samples.

• Journal of the Korean Society of Food Science and Nutrition
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• v.11 no.3
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• pp.47-52
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• 1982

The contents of efficient nutrients, especially calcium(Ca), phosphorus (P), $\alpha$-amino nitrogen($\alpha-amino$ N) and total nitrogen (total N) were observed to evaluate the Sagol bone stock as a calcium and protein source: In case of quantitative changes of nutrients in the bone stock as a result of boiling for two, four, eight and twelve hours, respectively, the Ca, $\alpha$-amino N and total N contents increased in the course of boiling, and showed maximum after twelve hours. P contents also increased during eight hours but decreased after twelve hours. By four hours of reboiling, the contents of nutrients in the second stock decreased in contrast with the duration of the preceding process. The Ca and $\alpha-amino$ N contents extracted for 4 hours from the Sagol bones which were boiled for two through eight hours amounted to almost 60$\sim$90% and the total N to 130% amount of their first stocks; Ca and P contents increased when the amount of the water exceeded by weight that of the bones over seven times; and $\alpha$-amino N and total N increased when that of the water exceeded over ten times. These results suggest that Sagol bone stock could be a valuable calcium and protein source by boiling for at least twelve hours with ten times of water (wt/wt).

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.3
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• pp.243-248
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• 1986

This study was examined the contents of calcium, phosphorus, magnesium, sodium, potassium, total nitrogen (total N) and free amino acid in shank bone stock as results of boiling for eight, twelve, sixteen and twenty hours. The results were as follows. 1) Contents of calium, sodium and potassium were increased according to boiling time, Content of calcium was more than two times after boiling for twenty hours as compared with eight hours. The contents of potassium and sodium were increased slightly but that of magnesium was constant in the course of boiling. The content of phosphorus was showed maximum value after toiling for eight hours and was decreased after boiling for twelve hours. 2) The content of total N was increased according to boiling time and showed moximum value after boiling for twenty hours. Total N was extracted more than two times after boiling for twenty hours as compared with eight hours. The content of free amino acid was little at various boiling time. The contents of glycine, glutamic acid and serine were increased according to boiling time. Glycine was the most abundant free amino acid and was followed in order of glutamic acid. alanine and serine.

• Ecology and Resilient Infrastructure
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• v.10 no.3
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• pp.85-96
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• 2023

The study involved the categorization of domestic lakes located in South Korea into three groups based on their salinity levels: upstream reservoirs with salinity less than 0.3 psu, estuarine reservoirs with salinity ranging from 0.3 to 2 psu, and brackish lagoons with salinity exceeding 2 psu. Subsequently, the research assessed variations in the concentrations of total nitrogen (T-N) and total phosphorus (T-P) in the sediment of these lakes using statistical analysis, specifically one-way analysis of variance (ANOVA). Additionally, a laboratory core incubation test was conducted to investigate the benthic nutrient fluxes in Songji lagoon (salinity: 11.80 psu), Ganwol reservoir (salinity: 0.73 psu), and Janggun reservoir (salinity: 0.08 psu) under both aerobic and anoxic conditions. The findings revealed statistically significant differences in the concentrations of T-N and T-P among sediments in the lakes with varying salinity levels (p<0.05). Further post-hoc analysis confirmed significant distinctions in T-N between upstream reservoirs and estuarine reservoirs (p<0.001), as well as between upstream reservoirs and brackish lagoons (p<0.01). For T-P, a significant difference was observed between upstream reservoirs and brackish lagoons (p<0.01). Regarding benthic nutrient fluxes, Ganwol Lake exhibited the highest diffusive flux of NH₄⁺-N, primarily due to its physical characteristics and the inhibition of nitrification resulting from its relatively high salinity. The flux of NO₃^--N was lower at higher salinity levels under aerobic conditions but increased under anoxic conditions, attributed to the impact of salinity on nitrification and denitrification. Additionally, the flux of PO₄^3--P was highest in Songji Lake, followed by Ganwol Lake and Janggun Reservoir, indicating that salinity promotes the diffusive flux of phosphate through anion adsorption competition. It's important to consider the influence of salinity on microbial communities, growth rates, oxidation-reduction processes, and nutrient binding forms when studying benthic diffusive nutrient fluxes from lake sediments.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.141-144
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• 2003

청양 및 서보광산에서 채취한 광미 및 오염된 토양에 대한 산성비를 고려한 용출실험 결과, 아연, 카드뮴 및 망간 pH 6.2-5.8, 철 pH 5.2-3.2, 코발트 pH 4.4-3.2, 구리 pH 3.2-3.0, 납과비소 pH3.0-3.5의 용출조건에서 최초로 각 원소의 용출이 발생하였다. 반응용액의 최종 pH5.0-1.5사이에서 용출되는 중금속은 이온교환형태 및 탄산염광물형태와 수반된 것이 용해된 것이다. 반응용액의 최종 pH1.5이하에서 용출되는 중금속은 철과 밀접하게 수반된 것으로 해석되었다. 청양광산과 서보광산의 광미가 pH2.0이하로 유지되는 경우가 발생한다면, 청양광산은 비소(최대 6,006$\mu\textrm{g}$/g), 아연(최대 2,503$\mu\textrm{g}$/g) 및 납(최대 29,638$\mu\textrm{g}$/g), 서보광산은 납(최대 2,258$\mu\textrm{g}$/g)과 111소(최대 874$\mu\textrm{g}$/g)의 오염확산이 크게 우려되며, 이 결과는 광미에 대한 환경복원이 필요한 것을 지시한다. 서보광산의 오염된 토양은 pH3.0까지의 산성비와 반응하는 경우에는 중금속의 오염확산이 거의 우려되지 않으며, pH3.0이하의 강산 용액과 반응한다면 아연의 오염확산이 우려된다.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.499-499
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• 2016

본 연구는 오염된 농업용 저수지에 대하여 수층에 따른 수질 변화 특성을 조사하고, 저수지 저부의 퇴적물에 대한 용출 실험을 통해 수층별 수질 특성이 퇴적물의 용출에 미치는 영향을 분석하고자 수행되었다. 연구 대상 저수지의 선정은 설치년도 1960년대를 기준으로 이전과 이후로 분류하였으며, 주요 오염원을 축산계와 생활계 오염원으로 분류하여 각 다른 특성을 가진 저수지를 선정하여 조사하였다. 내부 오염 부하량이 수체에 미치는 영향을 평가하기 위해 실시한 용출량 실험 결과, 호기 조건에서 축산계오염원 저수지의 T-P가 미미하게 용출이 일어난 것을 제외하고는 생활계, 축산계오염원 저수지에서 용출이 일어나지 않았다. 반면에 혐기 조건의 경우에는 생활계오염원 보다는 축산계오염원 저수지에서, 1960년대 이후 설치된 저수지에서 보다는 1960년대 이전에 설치된 저수지에서 용출이 크게 일어나는 것으로 조사 되었다. 혐기 조건에서 T-N의 경우 생활계오염원과 1960년대 이후 설치된 저수지에서는 용출이 일어나지 않았으나, 그 외의 항목에서는 모두 용출이 일어나는 것으로 분석되었다. 특히 혐기조건에서는 모든 연구대상 저수지에서 T-P의 용출이 크게 일어나는 것으로 조사되었는데, 이는 부영양화의 주요 영향인자로 작용할 수 있으므로 저수지 저부의 혐기조건이 형성되는 것을 제어?관리해야 할 필요성이 있다고 하겠다. 연구 저수지에 대한 현장 조사 결과, 가뭄의 영향으로 수위가 평년에 비해 상당히 낮았으며, 저수량의 부족으로 저수지 주변의 바닥이 드러나거나 유출이 없는 등의 특징을 보였다. 수심이 낮은 5~7월의 조사 시기에는 표층의 DO 농도가 높음에도 저층부의 DO 농도는 1.2~2.2 mg/L를 나타내 약혐기조건이 형성됨을 확인하였다. 또한 현장측정기(HYDROLAB_Quanta)를 이용한 DO측정시, 저층부 퇴적물의 재부유를 막기 위해 저층경계면에서 30~50cm 윗부분을 측정했다는 점에서 저층부 바닥면의 DO 농도가 더 낮을 수 있다고 추정할 수 있다. 이는 이 시기에 퇴적층에 존재하는 오염물질의 용출이 충분히 일어날 수 있으며, 이후 8~11월에 수계 내 환란 및 순환에 의해 오염물질이 수중으로 이동하게 되고, 수질을 악화시키는 원인으로 작용할 수 있음을 추론할 수 있다. 이와 같이 퇴적되어 있던 오염물질이 계속적으로 용출 및 순환을 해마다 반복한다면 해당 저수지는 장기간 수질 오염 저수지가 될 수밖에 없을 것이다. 따라서 이러한 내부오염부하가 크다고 판단되는 저수지에 대하여 오염퇴적물의 관리가 필요하다고 하겠다.

• Journal of Soil and Groundwater Environment
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• v.9 no.1
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• pp.87-94
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• 2004

The effects of pretreatment of GAC and dissolved oxygen (DO) on the sorption capacity for ο-cresol were investigated using pretreated GAC under oxic and anoxic conditions. Virgin GAC was used with pretreated GACs by $O_2$, acid and base as sorbents. Sorption capacity of GAC was dependent on the oxygen conditions according to the pretreatment methods. Virgin GAC showed increased sorption capacity when DO was present in the solution, while $O_2$-pretreated GAC did not show any considerable capacity change. Acid- and base-pretreated GACs were relatively more influenced by presence of DO as compared with virgin GAC. Both acid and base-pretreated GACs showed a rapid sorption rate at the initial stage, but as contact time became longer the sorption was slower. Sorbed ο-cresol was extracted with micro-Soxhlet extraction apparatus using the GAC separated from the rate experiments. Within 1 hour both acid and base-pretreated GACs showed the decrease in extraction efficiencies under both oxic and anoxic conditions. After 1 hour such a trend (the increase as contact time was longer) was not observed and showed relatively constant efficiencies of 35∼50%. According to the results of this study $O_2$contacted with GAC before sorption as well as DO present in the solution during sorption could influence the GAC sorption capacity.

• Journal of the Korean GEO-environmental Society
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• v.2 no.4
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• pp.29-38
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• 2001

In this study, the fractional composition and the releasing of nutrients and metals from sediments of Boryung reservoir were investigated. Based on present study, the forms of sediment phosphorus of the four sites in reservoir were classified as adsorbed phosphorus, non apatite inorganic phosphorus(NAI-P), apatite phosphorus and residual phosphorus. Residual phosphorus showed the highest fration, NAI-P second, apatite phosphorus third and absorbed phosphorus fourth. The sedimentation rate of T-P and T-N in aerobic condition were $0.31mg/m^2{\cdot}day$ and $29mg/m^2{\cdot}day$. The sedimentation rate of T-P and T-N in anaerobic condition were $0.12mg/m^2{\cdot}day$ and $13.6mg/m^2{\cdot}day$. The releasing rate of T-P and T-N in anaerobic condition were $0.23mg/m^2{\cdot}day$ and $10.5mg/m^2{\cdot}day$.