• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1071-1071
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• 2001

Near-infrared spectroscopy (NIRS) is potentially a powerful and revolutionary technology for environmental analysis. It is supported by a large body of scientific and experiential knowledge. The instrumentation is well-developed, with easy-to-use, highly dependable instruments, but at the same time it is still developing, particularly with the production of more portable and rapid instruments, and more powerful software. NIRS is used globally in numerous industries for commodity analysis. Yet NIRS is largely unknown in the field of environmental chemistry and monitoring, and is not even routinely used in soil analysis, where the research literature on NIRS extends over four decades. Part of the explanation for the poor visibility of NIRS is the fact that NIRS is not routinely taught in Chemistry programs in universities, where most environmental chemists and environmental technicians are trained. This presentation examines the unique capabilities of NIRS, such as rapid, real-time analysis; analysis of whole samples; simultaneous analysis of multiple constituents; cost-effectiveness, and portability, as they match needs for analysis in several environmental areas. Examples of NIRS usage and published and unpublished results will be described for such areas as soil and sediment analysis; water quality monitoring; and nutrient loading in application of manures and sewage sludge (biosolids) to land. Present barriers to the use of NIRS in environmental analysis will be discussed. It is argued that emerging environmental problems and increasing attention to some traditional problems will enhance the application of NIRS in the future.

• 한국대기환경학회지
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• 제14권6호
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• pp.599-606
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• 1998

Removal of toluene vapor from airstreams was studied in a biological reactor known as a biofilter. The biofilter was packed porous ceramic inoculated with thickened activated sludge (MLVSS 17,683 mg/L). The lab-scale biofilter was operated for 42 days under various experimental conditions including inlet toluene concentrations and flow rates of the contaminated air streams. Removal efficiency reached up 96.6% after 4 days from start up. Nutrient limitation was proposed as a reason for the decrease in biofilter performence. Biofilter performance decreased substantially, coincident with the buildup of back pressure due to accumulation of excess VSS within the medium bed. Practically, the bed needs to be backwashed when the overall pressure drop is greater than 460.6 Pa at SV (Space Velocity) 100 h-1. Periodic backwashing of the biofilter was necessary for removing excess biomass and attaining stable long -term high removal efficiency The removal efficiency of toluene in the biofilter decreased as the gas velocity and toluene concentration in the inlet gas increased. The maximum elimination capacity of ceramic biofilter could reach up to 444.85 g/m3. hr. When the loading of toluene exceed this critical value, substrate inhibition occurred.

• 한국토양비료학회지
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• 제45권5호
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• pp.690-697
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• 2012

Approximately 67% of the total land area of the Korea is covered by forest. Eutrophication, defined as the enrichment of waters beyond natural levels, principally by the nutrient phosphorus (P), is a serious cause of concern at the present time. The contribution of forestry to P loading in catchment waters has not been intensively studied in Korea, but is potentially important because forests are often located in near-pristine environments. Phosphorus is retained by most mineral soils and, as a consequence, losses are usually negligible. However, it is much more mobile in organic soils where it can be relatively easily leached or lost through surface runoff, as these soils have a low capacity to retain free phosphate. This report has been prepared to study the influence of arable land used for paddy, upland, and forestry on water quality in the basin of Daechung reservoir.

• 농촌계획
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• 제8권1호
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• pp.15-25
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• 2002

The study was carried out to investigate the water balance and losses of nutrients from paddy fields during cropping period. The size of paddy fields was 95 ha and the fields were irrigated from a pumping station. The runoff loading was the highest in June because of the high concentrations of nutrients due to applied fertilizer, When the runoff Bosses of nutrients were compared to applied chemical fertilizer, it was found that 39.1 % to 42.5 % of nitrogen lost via runoff while runoff losses of phosphorus account for 14.5 % to 17 % of the total applied amount during cropping period. When the ratio was calculated between nutrients losses by infiltration and the applied of chemical fertilizer, two year results showed 9.1% to 10.8% for nitrogen and 0.5% for phosphorus, respectively.

• 한국물환경학회지
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• 제28권3호
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• pp.409-417
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• 2012

SWAT model was applied for the Nakdong River Basin to characterize water quality variability and assess the feasibility of using the load duration curve to water quality management. The basin was divided into 67 sub-basins considering various watershed environment, and rainfall runoff and pollutant loading were simulated based on 6 year measurements of meteo-hydrological data, discharge data of treatment plants, and water quality data (SS, T-N and T-P). The results demonstrate that non-point source loads during wet season increase by 80 ~ 95% of total loads. Although the rate of water flow governs the amount of SS that is transported to the main streams, nutrient concentrations are highly elevated during dry season by being concentrated. This phenomenon is more pronounced in the lower basin, receiving large amounts of urban point source discharges such as treated sewages. Also, the load duration curves (LDC) demonstrate dominant source problems based on the load exceedances, showing that SS concentrations are associated with the rainy season and nutrients, such as T-P, may be more concentrated at low flow and more diluted at higher flow. Overall, the LDC method could be used conveniently to assess watershed characteristics and pollutant loads in watershed scale.

• 한국환경과학회지
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• 제16권3호
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• pp.369-376
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• 2007

This study was conducted to evaluate water quality in coastal sea of Kunsan using multivariate analysis. The analysis data in Coastal Sea of Kunsan use of surveyed data by the NFRDI from April 2000 to November 2002. Twelve water Quality parameter were determined on each sample. The results was summarized as follow ; Water quality in coastal sea of Kunsan could be explained up to 62.782% by four factors which were included in loading of nitrogen-nutrients by Keum river(24.688%), suspended solids variation (12.180%), seasonal climate variation (18.367%) and variation of DIP (10.546%). To analyze spatially and monthly variation by factor score, it was divided by inner area and outer area spatially, and spring and summer monthly. The result of time series analysis by factor score, inner area of Kunsan coastal sea(St.1 and St. 2) was the most affected by nitrogen-nutrient and suspended solids due to runoff by Keum river. It could be suggested from these results that it is important to reduce tile pollution loads from Kuem river for the control of the water quality in coastal sea of Kunsan.

• Asian-Australasian Journal of Animal Sciences
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• 제12권4호
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• pp.629-632
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• 1999

Constructed wetlands are being used for the removal of nutrients from livestock wastewater. However, natural vegetation typically used in constructed wetlands does not have marketable value. As an alternative, agronomic plants grown under flooded or saturated soil conditions that promote denitrification can be used. Studies on constructed wetlands for swine wastewater were conducted in wetland cells that contained either natural wetland plants or a combination of soybeans and rice for two years with the objective of maximum nitrogen reduction to minimize the amount of land required for terminal treatment. Three systems, of two 3.6 by 33.5 m wetland cells connected in series were used; two systems each contained a different combination of emergent wetland vegetation: rush/bulrush (system 1) and bur-reed/cattail (system 2). The third system contained soybean (Glycine max) in saturated-soil-culture (SSC) in the first cell, and flooded rice (Oryza sativa) in the second cell. Nitrogen (N) loading rates of 3 and $10kg\;ha^{-1}\;day^{-1}$ were used in the first and second years, respectively. These loading rates were obtained by mixing swine lagoon liquid with fresh water before it was applied to the wetland. The nutrient removal efficiency was similar in the rush/bulrush, bur-reed/cattails and agronomic plant systems. Mean mass removal of N was 94 % at the loading rate of $3kg\;N\;ha^{-1}\;day^{-1}$ and decreased to 71% at the higher rate of $10kg\;N\;ha^{-1}\;day^{-1}$. The two years means for above-ground dry matter production for rush/bulrushes and bur-reed/cattails was l2 and $33Mg\;ha^{-1}$, respectively. Flooded rice yield was $4.5Mg\;ha^{-1}$ and soybean grown in saturation culture yielded $2.8Mg\;ha^{-1}$. Additionally, the performance of seven soybean cultivars using SSC in constructed wetlands with swine wastewater as the water source was evaluated for two years, The cultivar Young had the highest yield with 4.0 and $2.8Mg\;ha^{-1}$ in each year, This indicated that production of acceptable soybean yields in constructed wetlands seems feasible with SSC using swine lagoon liquid. Two microcosms studies were established to further investigate the management of constructed wetlands. In the first microcosm experiment, the effects of swine lagoon liquid on the growth of wetland plants at half (about 175 mg/l ammonia) and full strength (about 350 mg/l ammonia) was investigated. It was concluded that wetland plants can grow well in at least half strength lagoon liquid. In the second microcosm experiment, sequencing nitrification-wetland treatments was studied. When nitrified lagoon liquid was added in batch applications ($48kg\;N\;ha^{-1}\;day^{-1}$) to wetland microcosms the nitrogen removal rate was four to five times higher than when non-nitrified lagoon liquid was added. Wetland microcosms with plants were more effective than those with bare soil. These results suggest that vegetated wetlands with nitrification pretreatment are viable treatment systems for removal of large quantities of nitrogen from swine lagoon liquid.

• 한국환경보건학회지
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• 제21권4호
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• pp.1-9
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• 1995

This study was carried to investigate the biodegradability of phenol in the wastewater with the two sludge blanket-packed bed reactor in series. Each reactor had a dimension of 0.09 m i.d. and 1.5 m height and consisted of two regions. The lower region was a sludge blanket of 0.5 m height and the upper region was a packed-bed of 1 m height. The packed bed region was charged with ceramic raschig rings of 10 mm i.d., 15 mm o.d. and 20 mm length. The reactors were operated at 35$\circ$C and the hydraulic retention time(HRT) was maintained 24 hours. The synthetic wastewater composed of glucose and phenol as major components was fed into the reactor in a continuous mode with incereasing phenol concentration. In addition, the nutrient trace metals($Na^+, Mg^{2+}, Ca^{2+}, PO_4^{3-}, NH_4^+, Co^{2+}, Fe^{2+}$ etc.) were added for growing anaerobes. The phenol concentration of the effluent, the overall gas production, the composition of product gas, the efficiency of COD reduction and the duration of acclimation period were measured to determine the performance of the anaerobic wastewater treatment system as the phenol concentration of the influent was increased from 600 to 2400 mg//l. Successfully stable biodegradation of phenol could be achieved with the anaerobic treatment system from 600 to 1, 800 mg/l of the influent phenol concentration. The upper level of influent phenol loading was high enough to meet most of the practical requirement. The duration of acclimation increased with the phenol loading. At steady state of the influent phenol concentration of 1800 mg/l, the treatment performance indicated the phenol reduction efficiency of 99%, the COD reduction efficiency of 99% and the gas production rate of 37 l/day. At the influent phenol concentration of 2400 mg/l, however, the operation of the treatment system was noted unstable. While the concentration of methane in biogas decreased with increasing the influent phenol loading, the carbon dioxide was increased. However, the concentration of hydrogen was varied negligibly. The concentration of methane was high enough to be used as a fuel. As a result, it is suggested that anaerobic phenol wastewater treament was economical in the sense of energy recovery and wastewater treatment.

• 대한환경공학회지
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• 제28권8호
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• pp.866-871
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• 2006

연속 회분식 방식의 실험실 규모 상향류 반응조를 사용하여 인 결정화공정을 이용한 영양물질 회수에 대한 연구를 수행하였다. 양이온 공급원으로서 산업폐기물인 폐석회와 마그네슘염을 이용하여 그 운전특성을 비교하였다. 이 연구는 고성능 발효조와 인 결정화 반응조로 구성된 새로운 통합 슬러지 처리 공정에 있어서 인 결정화공정의 성공적인 적용성 평가에 초점을 두고 있다. 발효조 유출수와 유사한 특성으로 제조된 합성폐수를 이용한 첫 번째 struvite 결정화 실험에서 반응은 $0.5{\sim}1$ hrs 사이의 반응시간에서 빠르게 진행되었는데, 그 동안 상당량(약 60% 이상)의 암모니아와 인이 제거되었다. 알칼리성 조건이라는 기질의 고유특성으로 인하여 암모니아 탈기 현상이 다소 발생하였으나 그 정도는 미미한 것(<5%)으로 나타났다. 또한 공기주입에 의한 이산화탄소 탈기조건을 추가적으로 제공하였을 때 struvite 형성속도의 향상은 일어나지 않았다. 실폐수로서 발효조 유출수를 사용한 두 번째 실험에서 stuvite 결정화를 위한 마그네슘염의 최적주입량은 struvite형성질량비와 유사한 0.86 g Mg $g^{-1}$ P이었다. 반면에 폐석회의 최적주입량은 0.3 g $L^{-1}$으로 다소 높게 나타났으며, 약 3시간의 반응시간 조건에서 $NH_4$-N과 $PO_4$-P의 제거효율은 각각 80%와 41%로 나타났다. 각 실험에서 침전물을 현미경으로 분석한 결과 마네슘염을 사용한 경우 프리즘과 같은 결정체가 관찰된 반면 폐석회를 사용한 경우는 비결정질의 결정체가 주로 관찰되었다. 하수처리용량 158,880 $m^3\;d^{-1}$의 실규모 처리시설의 경우를 대상으로 한 통합 슬러지처리시스템의 물질수지 분석결과 결정화 반응조 유출수로 부터의 반송되는 영양물질의 재순환 부하(각각 하수 1 $m^3$ 당 0.13 g N와 0.19 g P)는 매우 낮게 유지되는 것으로 나타났다. 그러므로 이미 산업폐기물 형태로 존재하는 폐석회를 본 연구에서와 같이 통합 슬러지 처리시스템의 영양물질 회수 공정에서 재이용하는 것은 높은 환경적 및 경제적 이익과 동시에 산업폐기물의 지속발전적 처리/처분이라는 다양한 장점을 가질 것이다.

• 한국산림과학회지
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• 제110권2호
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• pp.198-209
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• 2021

본 연구는 졸참나무, 물푸레나무, 느티나무를 대상으로 용기 규격이 시설양묘 과정에 질소 양분 특성에 미치는 영향을 구명하기 위해 수행되었다. 16 종류의 용기[4 생육밀도(100, 144, 196, 256본/m²) × 4 용적(220, 300, 380, 460 cm³/구)]에서 생산된 묘목의 질소 양분 특성을 조사·분석하였다. 생육밀도와 용적에 따른 용기묘의 질소 양분 농도 및 함량 변화를 알아보기 위해 이원분산분석 및 다중회귀분석을 이용하였다. 세 수종 모두 용기 규격에 따라 묘목의 질소 양분 특성은 유의적 차이를 보였으며, 생육밀도와 용적 두 요인간의 상호작용이 질소 농도 및 함량에서 확인되었다. 세 수종 모두 질소 함량과 용적은 정의 상관관계를 보였지만, 물푸레나무의 질소 함량은 생육밀도와 부의 상관관계를 나타냈다. 추가적으로 양분벡터분석을 실시하여, 용기 규격에 따른 시비 효과 차이로 양분결핍, 과량집적 등의 양분저장능력이 다르다는 것을 확인하였다. 묘목 질소 함량을 기준으로 다중회귀분석기법을 적용한 결과, 졸참나무는 180~210본/m²과 410~460 cm³/구, 물푸레나무는 100~120본/m²과 350~420 cm³/구, 느티나무는 190~220본/m²과 380~430 cm³/구가 최적 용기 규격으로 최종 도출되었다. 수종별 적정 용기 적용으로 시설양묘 과정에서 양분저장능력이 높은 묘목 생산과 함께 조림 후에도 우수한 생장을 기대할 수 있을 것이다.