• 한국농업기계학회:학술대회논문집
• /
• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
• /
• pp.692-700
• /
• 1996

The objective of this study is to develop a systematic purification plant using the metabolism of aerobic microorganisms. This system is subsequently aerated and continuously removes suspended solids and settling sludges caused by aerating pressure at the bottom of a lower pipe (i.e., Continuous Removal of Suspended solids and Settling sludges, CRSS). The CRSS plants are brought out by introducing fine air bubbles into the liquid phase of a lower pipe in the bio-reactor. These plant uses aeration pipe, with multiple inlets to sweep the floor of bio-reactor tank, instead of the conventional scraper mechanisms. The principal advantage of this system is that it can continuously remove very small or light particles that settles completely within a short time. Once the particles have been floated to the surface, they can be moved into the pipe and collected in the settling tank by sequently aerated pressure. The experimental results shows that about 99.0% of the biochemical oxygen demand(BOD), 99.3% of the suspended solid(SS), 92.3% of the total nitrogen(T-N), 99.0% of the turbidity(TU), 100% of the total coliform(TC)and ammonia was respectively removed during aerobic digestion for 9 days. These result indicates that the CRS S plants are very effective for reduction and deodorization of swine wastewater contaminants, and the efflux from CRS S can either be discharged in the river or used as nutrient solution of formulation for plant growth factories. The developed CRSS plant proved to be flexible and it can simply be adapted to any type of biological waste treatment problem.roblem.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 2005년도 학술발표논문집
• /
• pp.673-678
• /
• 2005

The objective of this paper is to develop the microorganism concentration simulation model for the health related effect analysis while farmers and water managers reuse the wastewater for agricultural irrigation. This model consists of the CE-QUAL-R1 model and the CREAMS-PADDY model. The CE-QUAL-R1 model is the 1-D numerical model to analyze the water quality of the reservoir and the CREAMS-PADDY model is modified from CREAMS model for considering the hydrologic cycles in paddy field. This model was applied to examine the application by the observed data from 2003 in Byoungjum study area. From this research, the average root mean square error (RMSE) for the simulated concentration during the calibration period was 0.51 MPN/100ml and correlation coefficient $(R^2)$ was 0.71. And the RMSE for the simulated concentration during the verification period was 0.46 MPN/100ml and $R^2$ was 0.73. This simulation results show that the coliform inflow concentrations by the wastewater irrigation wield great influence upon the temporal coliform concentrations in paddy field.

• 한국농공학회논문집
• /
• 제54권6호
• /
• pp.53-63
• /
• 2012

The objectives of this study were to develop a linked watershed-waterbody modeling system and to assess the impacts of indirect wastewater reuse on irrigation water quality. The Osan stream watershed within Gyeonggi-do of South Korea was selected for this study. The linked modeling system was composed of the SWAT (Soil and water assessment tool) and QUALKO2 models. The SWAT model was calibrated and validated using the stream discharge and water quality data from 2010 to 2011. Runoff and non-point source pollutants from each subbasin and stream discharge from 1980 to 2009 were simulated by the SWAT model and applied to the QUALKO2 model. The QUALKO2 model was calibrated and validated under the conditions of low water and normal discharges, respectively. Finally, The 10-day irrigation water quality from April to September was simulated. The statistical measures of coefficient of determination ($R^2$), reliability index (RI), and efficiency index (EI) were used to evaluate the system performance. The $R^2$, RI and EI values ranged from 0.5 to 1.0, 1.03 to 1.92, and -35.03 to 0.95, respectively. The 10-day irrigation water quality showed the concentrations of BOD and coliform exceeded the water quality guidelines for wastewater reuse. The linked modeling system can be a useful tool to estimate non-point source pollutant loads in watershed and to control the water quality of effluent from a wastewater treatment plant and irrigation water in the downstream waterbody.

• Journal of Biosystems Engineering
• /
• 제31권1호
• /
• pp.46-51
• /
• 2006

This study was carried out to recover phosphorus in animal wastewater using a magnesium source. $MgCl_2$, as a magnesium source, was shown a SP (soluble phosphorus) recovery rate of 98% in both the aeration and the NaOH tests to adjust pH around 8.5. In case of MgO, the recovery rate of SP were 88% with the aeration and 58% with the NaOH. In case of ammonia nitrogen recovery, $MgCl_2$ was shown the recovery rate of 17% with aeration and 18% with NaOH. MgO was shown the ammonia recovery rate of 18% with aeration and 11% with NaOH. At low temperature of $6-8^{\circ}C$ with the animal wastewater from piglet stall, the recovery rate of SP was shown 95% with NaOH and 92% with aeration using $MgCl_2$. The recovery rate of ammonia nitrogen was shown 9% with NaOH and 12% with aeration, respectively. It was observed that the pH can be raised by aeration. The reaction was completed within 5 minutes and the struvite cristal structure was formed and could be observed with an electronic microscope.

• Journal of Microbiology and Biotechnology
• /
• 제12권4호
• /
• pp.569-575
• /
• 2002

Two bacterial strains capable of degrading trichloroethylene (TCE), isolated form soils contaminated with various chlorinated alkenes, were identified as Alcaligenes odorous N6 and Nocardia sp. Hl7. In addition, four KCTC strains, including three strains of Pseudomonas putida and one strain of Sphingomonas chlorophenolica, exhibited an ability to degrade toluene. A. odorans N6 and Nocardia sp. H17 degraded 84% of the initial amount of TCE in a basal salts medium (BSM), containing 0.2 mM TCE as the sole source of carbon and energy, in a day. The optimal pH for growth was within a range of 7.0-8.0. A mixed culture of the four toluene-degrading isolates degraded 95% of 0.2 mM TCE with 1.5 mM toluene as an inducer, whereas no TCE was degraded by the same mixture without an inducer. When a mixed culture of all 6 isolates was used, the degradation efficiency of 0.2 mM TCE was 72% without an inducer, in a day, and 82% with toluene as an inducer. In a continuous treatment, 1,000 mg/1 of TCE in an artificial wastewater was completely removed within 18 h when an activated sludge was used along with the microbial mixture, which was 27 h laster than when only an activated sludge was used. Accordingly, it would appear that such a microbial mixture could be effectively applied to the biological treatment of wastewater containing TCE with or without an inducer.

• 한국환경과학회지
• /
• 제28권12호
• /
• pp.1199-1208
• /
• 2019

Korea's protected horticulture is rapidly increasing in scale due to various advantages such as year-round harvesting, labor savings through automation and shortened culture period, and greater income generation. This study was conducted to investigate the impact of protected horticulture on water quality. The results of this study are expected to provide basic data contributing to improvements towards sustainable agriculture and eco-friendly design of protected horticulture complex. The average T-N and T-P loads from vinyl greenhouses were 286.55± 143.98 mg/L and 59.14±13.77 mg/L, respectively and those from glass greenhouses 380.68 ± 150.41 mg/L and 61.85±20.72 mg/L. The annual discharge of wastewater derived from the monthly discharge from the horticulture greenhouses were estimated at 2597 ton/ha, with the annual phosphorus load amounting to 155.3 kg/ha. The average T-N and T-P loads in the tested greenhouse effluents were in excess of 8.3- and 13.5-fold the standards for the Korean wastewater plant effluent. The waste nutrient solution discharged from a protected horticulture complex can cause water contamination. Therefore, there is a need to conduct follow-up research using a water purification system or a trench method to develop a eco-friendly protected horticulture complex for sustainable agriculture.

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

• 유기물자원화
• /
• 제20권2호
• /
• pp.53-65
• /
• 2012

본 연구에서는 국내 농공단지로부터 배출되는 폐수를 대상으로 폐수의 처리효율 특성을 전형적인 $A_{2}O$ 공정계열의 변법인, 배양조-혐기조-간헐포기조로 구성된 HBR-II 공정을 적용하여 이를 규명하고자 하였다. 또한 고도처리를 위한 상용화 플랜트 설계 시에 공정 조업 및 제어변수 값을 도출하고 HBR-II 공정의 고도처리 효율성을 경제적 측면에서 분석검토 하고자 하였다. 이를 위해 본 실험에서는, HBR-II 공정을 bench (또는 pilot) 규모의 실험 장치에 적용시켜 처리효율 실험을 수행하였으며, 1차 침전지 설계를 위한 회분식(batch type) 침전실험과 인(T-P)의 제거와 2차 침전지로부터의 난분해성 미세 부유고형물 입자의 배출농도 안정화를 위한 응집실험을 병행하여 이를 고도처리효율과 연계하여 최적의 침전 및 응집을 위한 공정조업 변수 값을 도출하고자 하였다. F/M비를 0.20~0.25 $BOD_5/Kg{\cdot}MLSS/Day$로 유지시켰으며, $BOD_5$ 98.4%, $COD_{Mn}$ 92.9%, SS 97.5%, T-N 91.3%, T-P 82.3% 의 높은 제거효율을 나타내었다. 본 연구를 통하여서 HBR-II 공정을 농공단지 폐수처리에 접목 할 경우 안정적인 수처리가 가능할 것으로 사료된다.

• 한국환경농학회지
• /
• 제28권2호
• /
• pp.171-178
• /
• 2009

기후변화로 인해 발생될 수 있는 물 부족 현상에 대응하기 위하여 기존 농업용수에 대한 대체용수로 하수처리수 및 폐양액의 재이용이 유식물 생장에 미치는 영향을 평가하였다. 하수처리수와 폐양액에 대한 수질분석결과 유기배지로부터의 폐양액은 무기배지로부터의 폐양액 및 하수처리수와 비교해서 보다 많은 양분을 함유하고 있었으며 하수처리수에서는 $Na^+$과 $Cl^-$ 함량이 다른 용수보다 높은 것으로 나타났다. 배추묘의 생육은 폐양액 처리구에서 대조구인 지하수 처리구에 비해 유사하거나 촉진되었고 하수처리수 처리구에서는 대조구와 비슷하게 나타났다. 육묘기간 동안 배추묘가 흡수한 질소는 관행재배에서 5.47 mg/plant 이었으며, 유기배지와 무기배지로부터의 폐양액 처리구에서 각각 10.02 mg/plant, 5.20 mg/plant인 것으로 나타났다. 하수처리수 처리구에서는 배추의 질소함량이 4.59 mg/plant으로 나타났다. 관행의 1/2 수준으로 시비하고 유기배지로부터의 폐양액을 처리한 배추의 질소 흡수량은 8.34 mg/plant으로 관행재배보다 높은 것으로 나타나 폐양액 이용 시 육묘에 이용되는 비료의 시용을 줄여야 할 것으로 판단된다. 한편 배추의 인 함량은 관행재배에서 8.9 ${\mu}$g/plant로 나타났으며 유기배지로부터의 폐양액 처리구에서도 관행재배와 비슷한 수준이었다. 반면 인 함량이 낮았던 무기배지로부터의 폐양액과 하수처리수 처리구에서 배추가 흡수한 인산 함량이 가장 높은 것으로 나타났다. 배추묘가 흡수한 양이온의 경우 관행재배에 비해 폐양액과 하수처리수 처리구에서 상대적으로 많은 양을 흡수하였다. 이상의 결과로부터 선정된 폐양액 및 하수처리수에 대한 농업용수로써의 재이용 가능성을 확인할 수 있었으며 향후 현장실험을 통해 작물의 생육특성 및 생산량 평가를 실시하고 대체용수 사용에 따른 환경영향을 평가하는 연구가 진행되어야 할 것으로 판단된다.

• 한국잠사학회:학술대회논문집
• /
• 한국잠사학회 2005년도 제48회 추계 학술연구 발표회
• /
• pp.38-38
• /
• 2005