• 한국습지학회지
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• 제9권1호
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• pp.69-78
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• 2007

Constructed wetlands and other aquatic systems have been successfully used for waste and wastewater treatment in either temperate or tropical regions. To treat waste or wastewater in a sustainable manner, the integrated eco-engineering designs are explained in this paper with 2 case studies: (i) a combination of vertical-flow constructed wetland (CW) with plant irrigation systemfor fecal sludge management and (ii) integrated CW units with landscaping at full-scale application for domestic wastewater treatment. The pilot-scale study of fecal sludge management employed 3 vertical-flow CW units, each with a dimension of $5{\times}5{\times}0.65m$ (width ${\times}$ length ${\times}$ media depth) and planted with cattails (Typha augustifolia). At the solid loading rate of 250 kg total solids (TS)/$m^2.yr$ and a 6-day percolate impoundment, the CW system could achieve chemical oxygen demand (COD), TS and total Kjeldahl nitrogen (TKN) removal efficiencies in the range of 80 - 96%. The accumulated sludge layers of about 80 - 90 cm was found at the CW bed surface after operating the CW units for 7 years, but no clogging problem has been observed. The CW percolate was applied to 16 irrigation Sunflower plant (Helianthus annuus) plots, each with a dimension of $4.5{\times}4.5m$ ($width{\times}length$). In the study, the CW percolate were fed to the treatment plots at the application rate of 7.5 mm/day but the percolate was mixed with tap water at different ratio of 20%, 80% and 100%. Based on a 1-year data of 3-crop plantation were experimented, the contents of Zn, Mn and Cu in soil of the experimental plots were found to increase with increasing in CW percolate ratios. The highest plant biomass yield and oil content of 1,000 kg/ha and 35%, respectively, were obtained from the plots fed with 20% or 50% of the CW percolate, whereas no accumulation of heavy metals in the plant tissues (i.e. leaves, stems and flowers) of the sunflower is found. In addition to the pilot-scale and field experiments, a case study of the integrated CW systems for wastewater treatment at Phi Phi Island (a Tsunami-hit area), Krabi province, Thailand is illustrated. The $5,200-m^2$ CW systems on Phi Phi Island are not only for treatment of $400m^3/day$ wastewater from hotels, households or other domestic activities, but also incorporating public consultation in the design processes, resulting in introducing the aesthetic landscaping as well as reusing of the treated effluent for irrigating green areas on the Island.

• 농촌계획
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• 제12권2호
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• pp.57-64
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• 2006

The experiment was carried out to determine the distribution of total coliform the translocation of heavy metals and the salt accumulation in soils following the supply of ground water, the domestic wastewater and the ultraviolet treatment of domestic wastewater during the spinach and the chinese cabbage cultivation. There were not much changes in the Total-N, Total-P and cations in soils following the ultraviolet treatment of the domestic wastewater. However, the density of total coliform was dramatically reduced from 894MPN/100mL to 5MPN/100mL. The diagnosis of composition of soil after the harvest of chinese cabbages and spinach has shown that the concentration of Na$^+$ was 3-4 times higher in plot using domestic wastewater than in plot using ground water. When domestic wastewater and ground water were used in growing spinach md chinese cabbage at 50% each, the application of chemical fertilizers reduced about 25% to 50% compared to the criteria set down by the Rural Development Administration and there was not significant difference in terms of harvest. Using non-ultraviolet treatment of domestic wastewater directly on spinach and chinese cabbage has resulted in excessive density of total coliform at 25,000MPN/100mL. Even when ultraviolet treatment, the density was still high at 2,000MPN/100mL. The high density of total coliform even following ultraviolet treatment of domestic wastewater is considered to be caused by photo-reactivation of micro-organism. When reusing domestic wastewater, the application of sterilization such as ultraviolet, ultrasonic and electron-beam for public health and hygiene reasons may provide safe supply of agricultural water.

• International Journal of Industrial Entomology and Biomaterials
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• 제18권2호
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• pp.97-103
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• 2009

Sericulturists in the vicinity of Bangalore city irrigate their mulberry gardens with Vrishabhavathy stream water, which is polluted with domestic and industrial wastes from the city. To investigate the effect of pollutants on silkworm crops, a detailed field survey was conducted to study the cocoon yield pattern of the crops raised on mulberry irrigated with wastewater as against irrigation by bore/open wells. The villages along the stream were grouped into five test batches at about a distance of $5{\sim}8$ km from each other. The seasonal yield data with relevant information were collected through questionnaires from 117 rearers using stream water and 35 rearers using bore/open wells, the latter serving as control group. The average yield for 100 layings was 46 to 57 kg in the control group whereas in test groups, it ranged between 34 to 51 kg in the first test group and 22 to 38 kg in the rest. The difference in yield was $9{\sim}19$ kg depending on the season between control and test batches. In summer, this difference was higher, with high co-efficient of variation in test groups ($33{\sim}52$%). Further, water, soil and leaf samples were collected from selected rearers and were analyzed for zinc, copper, iron, lead and nickel. Results indicated significantly higher contents of these metals in samples from gardens using wastewater when compared control samples. Significantly (p<0.05 & p<0.01)) higher levels of zinc ($24{\sim}122$ ppm) and iron ($208{\sim}683$ ppm) were noticed in mulberry leaves during summer followed by winter and rainy season. The significance of high content of heavy metals in mulberry leaves and cocoon yield pattern of this area in relation to the quality of irrigation water is discussed.

• Advances in environmental research
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• 제9권4호
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• pp.233-249
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• 2020

To date, there is no central wastewater (WW) treatment plant in Erbil city, Kurdistan region, Iraq. Therefore, raw WW disposes to the environment and sometimes it used directly for irrigation in some areas of Erbil city. Disposal of the untreated WW to the natural environment and using for irrigation it causes problems for the people and the environment. The aims of the current work were to study the characteristics, design of primary and different secondary treatment units and reusing of produced WW. Raw WW samples from Ashty city-Erbil city were collected and analyzed for twenty three quality parameters such as Total Suspended Solids (TSS), total dissolved solids, total volatile and non-volatile solids, total acidity, total alkalinity, total hardness, five-day Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), biodegradability ratio (BOD5/COD), turbidity, etc. Results revealed that some parameters such as BOD5 and TSS were exceeded the standards for disposal of WW. Design and calculations for primary and secondary treatment (biological treatment) processes were presented. Primary treatment units such as screening, grit chamber, and flow equalization tank were designed and detailed calculation were illustrated. While, Conventional Activated Sludge (CAS), Sequencing Batch Reactor (SBR) and Moving Bed Biofilm Reactors (MBBR) were applied for the biological treatment of WW. Results revealed that MBBR was the best and economic technique for the biological treatment of WW. Treated WW is suitable for reusing and there is no restriction on use for irrigation of green areas inside Ashty city campus.

• 한국환경농학회지
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• 제27권3호
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• pp.225-230
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• 2008

하수종말처리장 방류수를 이용한 포장적응시험에서 토양 검정시비량의 50%시비수준에서 대체용수원 20일 관개구의 벼 생육 및 수량은 비교적 대조구와 비슷하게 나타났다. 표면수의 수질에 대한 $EC_i$ 및 SAR값은 하수종말처리장 방류수 관개구가 지하수 관개구에 비해 2배 이상 높은 것으로 나타났다. 관개기간별 하수종말처리장 방류수 10일과 20일 관개구의 표면수 $EC_i$ 및 SAR값은 유의차가 없었지만, 생육초기 단계에서 30일간 관개구에서 가장 높게 나타났다. 그리고 침출수중의 $EC_i$ 및 SAR값은 비료시용 수준별 및 대체용수 관개기간에 따라 일정한 경향을 보이지 않았다. 결론적으로 이앙기의 한발기 20일 동안은 검정시비량의 50% 시비수준으로 하수종말처리 방류수를 관개할 수 있는 것으로 판단된다. 그리고 한발 20일 동안 대체용수 관개 이용 효율성은 벼 재배기간 동안 총 관개량에 비교하여 32.7%인 것으로 나타났다.

• 한국농공학회논문집
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• 제56권6호
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• pp.45-53
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• 2014

This study presents a system dynamics modeling approach to simulate daily streamflow in a watershed including wastewater treatment plant which contributes to irrigation water supply. The conceptual system dynamics model considering the complex and dynamic hydrological processes in the watershed was developed. The model was calibrated and validated each for two years based on observed flow data. Model performances in terms of $E_{NS}$, RSR, PBIAS, and $R^2$ were 0.64, 0.60, -3.6 %, and 0.64 for calibration period, and 0.66, 0.58, -2.6 %, and 0.66 for validation period, respectively, showing an applicability on generating the daily streamflow. System dynamics modeling approach could help better understand the hydrological behavior of the watershed being reused wastewater for agriculture, by providing graphical dynamics of the hydrological processes as well as conventional rainfall-runoff model results.

• 한국환경농학회지
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• 제28권2호
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• pp.171-178
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• 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.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.267-270
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• 2003

This paper presents a recent finding from the progressed research efforts on the application for wastewater reclamation and reuse for agricultural uses. Reclaimed effluents from the Suwon municipal sewer treatment plant has been used to irrigate paddy rice at experimental plots. Three levels of reclamation treatments, filtration, disinfection, and the both, and one treatment to apply heavily polluted stream flow are compared to the control which uses groundwater for irrigation. The rice growth indicated by plant height and tiller number, and the yields were compared statistically among the five treatments. The results showed that the rice yields from polluted stream were greatest, and the control showed the lowest yields. And the first year experiment indicated that the agricultural reuse is promising.

• Membrane and Water Treatment
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• 제8권5호
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• pp.423-435
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• 2017

Settling Basins are one of the most important and popular methods for removal of suspended sediments irrigation and drainage networks or power canals taking off from an alluvial river and wastewater treatment plant. Improving the performance and so increasing sediment removal efficiency of settling basins by an alternative method is necessary. In the present work, the effect of baffle and its angle of attack with the flow (${\theta}$) on the sediment removal efficiency is investigated by conducting a series of experiments on a straight canal with 8 m length, 0.3 m width and 0.5 m height and 3 m length of basin equipped with an adjustable glass baffle. A numerical analysis has been carried out using ANSYS Fluent 3D software (a general purpose computational fluid dynamics simulation tool) for three Froude numbers from the experiments. The numerical and experimental results were found to match reasonably well.

• Environmental Engineering Research
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• 제16권4호
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• pp.243-252
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• 2011

Several mathematical relationships have been developed to describe bacterial responses to UV irradiation. Pseudomonas aeruginosa was taken as a bacterial model. The results obtained showed that the kinetics of disinfection is far to be as uniform. In fact, application of the model of Chick-Watson in its original form or modification, taking into account the speed change during the disinfection process, has not significantly improved results. The application of both models of Collins-Selleck and Hom constitute a major opportunity to simulate goodly the kinetics of UV disinfection. The results obtained showed that despite the major advantage held by applying the Hom model in this process of disinfection and for all strains studied, the model of Collins-Selleck gave the best results for the description of the UV inactivation process. The design of reactors, operating in continuous disinfection system, requires taking into account the hydrodynamic behaviour of water in the reactor. Knowing that a reduction of 4-log is necessary in the case of wastewater reuse for irrigation, a model integrating the expression of disinfection kinetics and the hydrodynamics through the UV irradiation room was proposed. The results highlight the interest to develop reactors in series working as four perfectly mixed reactors.