• Environmental Engineering Research
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• 제8권3호
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• pp.152-161
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• 2003

• 한국습지학회지
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• 제4권2호
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• pp.23-41
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• 2002

In this paper, changes of the coliform bacteria were investigated when aquatic plant pond was used for separating algal particles from waste stabilization ponds(WSPs). Three different types of integrated natural systems were operated. It was found that there were no significant interferences for the disinfection efficiency of two integrated systems (WSPs coupled with water hyacinth ponds) used for treating domestic sewage and upgrading the secondary effluent as well. However, when constructed wetland (CW) was combined with the shallow algal ponds and used for the secondary effluent, it seriously interfered with the disinfection efficiency due to the regrowth and/or after-growth of the coliform bacteria, which can readily metabolize the amino acids and sugars leached from plants. In order to find out the primary disinfection parameters, several sets of the batch test were run. It was found that sunlight is the most predominant factor for the coliform decay. During the night, algal toxicity partly supports the decay but during the day, deteriorates it by attenuating the sunlight. The pH in the range of 4 to 10 did not affect the decay in the dark.

• Environmental Engineering Research
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• 제19권3호
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• pp.185-195
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• 2014

Despite the enormous technical and economic efforts to improve environmental conditions, currently about 40% of the global population (or 2 billion people) are still lack access to safe water supply and adequate sanitation facilities. Pollution problems and transmission of water- related diseases will continue to proliferate. The rapid population growth and industrialization will lead to a reduction of arable land, thus exacerbating the food shortage problems and threatening environmental sustainability. Natural systems in this context are a transdisciplinary approach which employs the activities of microbes, soil and/or plants in waste stabilisation and resource recovery without the aid of mechanical or energy-intensive equipments. Examples of these natural systems are: waste stabilisation ponds, aquatic weed ponds, constructed wetlands and land treatment processes. Although they require relatively large land areas, the natural systems could achieve a high degree of waste stabilisation and at the same time, yield potentials for waste recycling through the production of algal protein, fish, crops, and plant biomass. Because of the complex interactions occurring in the natural systems, the existing design procedures are based mainly on empirical or field experience approaches. An integrated kinetic model encompassing the activities of both suspended and biofilm bacteria and some important engineering parameters has been developed which could predict the organic matter degradation in the natural systems satisfactorily.

• Environmental Engineering Research
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• 제23권4호
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• pp.442-448
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• 2018

This paper presents the numerical simulation of advection-diffusion mechanism of BOD concentration which was used as an indicator of waste only in one flow-direction of waste stabilization ponds (1-dimension (1-D)). This model was represented in partial differential equation order 2. The purpose of this paper was to determine the simulation of the model 1-D of wastewater transport phenomena based advection-diffusion mechanism and did validate the model. Numerical methods which was used for the solution of this model is finite difference method with Forward Time Central Space scheme. The simulation results which was obtained would be compared with field observation data as a validation model. Collection of field data was carried out in the Wastewater Treatment Plant Sewon, Bantul, D.I. Yogyakarta. The results of numerical simulations were indicate that the advection-diffusion mechanism takes place continuously over time. Then validation of the model was state that there was a difference between the calculation results with the field data, with a correlation value of 0.998.

• 대한환경공학회지
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• 제27권3호
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• pp.323-329
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• 2005

본 논문은 호기-혐기 조건이 연속적으로 반복 운영되는 자연정화시스템의 질소제거에 관한여 연구하였다. 조류 광합성 활동을 극대화한 산화지(WSP: Waste Stabilization Pond)에서 호기조건을, 부레옥잠 잎과 줄기에 의해 태양광이 차단되어 산화지로부터 유입된 조류의 내호흡과 뿌리에 부착된 미생물 호흡에 의해 혐기조건이 형성되는 WHP(Water Hyacinth Pond)를 조합하여 운전하였다. Pilot plant는 2개 계열로 구성하여 운전하였다. 첫번째는 WHPs와 WSPs로 조합하였고, 두번째는 WSP와 질산화와 탈질화에 대한 식물의 효과를 평가하기 위해 대조반응조로 태양광을 차단한 반응조(DPs: Dark Ponds)를 조합하였다. 연구결과에 따르면 질소에 대한 전체적인 제거능력은 WSP-WHP에서 발휘되었으며 약 86%가 감소되었고 대조반응조 WSP-DP에서는 36%가 감소되었다. 대부분 질소는 WSP에서 질산화 된 후 WHP에서 탈질에 의해 제거되었다. 탈질이 원활히 수행될려면 외부탄소원이 필요한데 수생식물조 하부 수층에서 조류의 부패로 탄소원이 공급되었다. 그리고 WSP-WHP 시스템은 인 제거에도 매우 효과적이었다. WSP-WHP에서 인 제거율은 81%인 반면에 WSP-DPs에서는 단지 16%에 불과했다. 이들 두 시스템간의 인 제거율의 차이는 아마도 식물증식과 식물 뿌리에서 생산된 Extra-cellular 물질에 기인한다고 여겨지며 이러한 부분에 대해서는 향후 심도 있는 연구가 진행되어야 할 것이다.

• 환경위생공학
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• 제11권1호
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• pp.83-91
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• 1996

It is not too much to say that the territorial inhabitants' concerns are wholly c concentrated on the environmental preservation-problem and development-problem in Korea given effect to the local self-government system. At a time like this I was studied the effect on nutrients removal through lighting period in aerobic high rate pond and we know that waste stabilization pond method is the most economical and energy saving wastewater treatment technology than others. At the results which was studied through operating the reactor-l artifically main-tained at a temperature, $25^{\circ}C$, a light intensity, 3000lux, and a lighting period, 24hrs and the reactor-2 artifically maintained at a tern야rature, $25^{\circ}C$ and a light intensity 3000lux, and a lighting period period, 12hrs, It has appeared for 24hrs.-lighting period -reactor-1 to be prior to the reactor-2. The attained results are that 1. reactor-1 is prior to reactor-2 on oxygen-generation 2. reactor-1 is prior to reactor-2 on algal production 3. COD removal efficiency, 90.76%, T-N removal efficiency, 80%, T-P removal e efficiency, 74.47 % in reactor-2, in reactor-1 COD removal efficiency, 94.85 %, T-N removal efficiency, 98.07%, T-P removal efficiency, 72.13% are, so the treatment efficiency of reactor-1 is more excellent than things of reactor-2 4. it appeared that the detention time is 8, 9days.

• Environmental Engineering Research
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• 제24권1호
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• pp.127-136
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• 2019

Land application of treated palm oil mill effluent (TPOME) could be used as an alternative tertiary wastewater treatment process. However, phenolic compounds in TPOME might be leached to the environment. This study investigated the ability of grasses on reducing phenolic compounds in the leachate after TPOME application. Several pasture grasses in soil pots were compared after irrigating with TPOME from stabilization ponds, which contained 360-630 mg/L phenolic compounds. The number of soil bacteria in planted pots increased over time with the average of $10^8CFU/g$ for mature grasses, while only $10^4-10^6CFU/g$ were found in the unplanted control pots. The leachates from TPOME irrigated grass pots contained lower amounts of phenolic compounds and had lower phytotoxicity than that of control pots. The phenol removal efficiency of grass pots was ranged 67-93% and depended on grass cultivars, initial concentration of phenolic compounds and frequency of irrigations. When compared to water irrigation, TPOME led to an increased phenolic compounds accumulation in grass tissues and decreased biomass of Brachiaria hybrid and Brachiaria humidicola but not Panicum maximum. Consequently, the application of TPOME could be conducted on grassland and the grass species should be selected based on the utilization of grass biomass afterward.

• 한국환경농학회지
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• 제19권4호
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• pp.339-344
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• 2000

축산폐수를 처리하는 연못시스템의 1차연못 처리수(평균 $BOD_5\;49.1mg{\cdot}L^{-1}$, $T-N\;48.6\;mg{\cdot}L^{-1}$)를 1주에 2 - 3회 실험양어지에 공급하여 잉어의 성장을 조사하였다. 처리수 공급유량과 실험양어지의 유량이 1:4가 유지되도록 공급하였으며, 실험양어지의 평균 $BOD_5$는 $15\;-\;20\;mg{\cdot}L^{-1}$였다. 양어지에 수용한 잉어의 평균 체중은 8월에 204.2 g에서 9월과 10월에 210.4 g와 219.3 g로 각각 늘었으며 60일간 사육에서 생잔율이 82%였다. 운반 및 조사시 잉어에 주는 스트레스를 감안하면 양어지의 수질과 환경은 잉어 성장에 나쁘지 않았다고 여겨진다. 8월부터 10월 사이의 다소 낮은 성장률은 양어지의 물을 빼내고 잉어를 잡아 체중과 체장을 측정하는 과정이 잉어에 스트레스를 준데 원인이 있다고 사료된다. 월동 후인 이듬해 4월에 잉어의 평균 체중은 205.3g로 감소하였으며 전년도 10월과 비교하여 생잔율은 83%였다. 일반적으로 잉어는 월동 후에 체중이 약 10 - 20% 감소하는 경향이 있다. 양어지 실험결과 양어지의 평균 $BOD_5$가 $15\;-\;20\;mg{\cdot}L^{-1}$로 유지되면 용존산소결핍으로 잉어가 일시에 죽는 현상은 일어나지 않음을 알 수 있었다. 평균 $BOD_5$와 T-N이 각각 27.9, $30.8\;mg{\cdot}L^{-1}$인 2차연못에 체중 약 100g 정도의 잉어 10마리를 8월에 넣어 보았으나 1주일 이내에 모두 죽었다. 새벽 무렵의 급격한 용존산소결핍 현상에 원인이 있다고 사료된다. 연못시스템의 3차연못에 잉어를 직접 털어 성장을 분석하였다. 3차연못의 평균 $BOD_5$와 T-N은 각각 $19.8\;mg{\cdot}L^{-1}$, $21.0\;mg{\cdot}L^{-1}$였다. 3차연못은 2차연못에서 발생한 조류(algae)가 죽어 연못바닥으로 침전되는 마무리연못(maturation pond)으로 연못전체가 호기성을 유지하고 있었다. 3차연못에 8월에 넣은 잉어의 평균체중은 107.5g였으며 2개월 후에 165.2g으로 증가하였다. 사육 1년 후의 평균체중은 478.2g으로 약 3배 증가했으며, 1년 후의 잉어 생잔율도 86%로 높게 나타났다. 월동을 했다는 것을 고려한다면 매우 좋은 성장이다. 생잔율이 높게 나타난 원인은 측정 횟수가 적어 측정에 따른 스트레스가 적었다는 점과 3차연못의 환경조건 (수질, 먹이 등)이 잉어사육에 적합했다고 사료된다. 사료공급 없이 하${\cdot}$폐수를 재활용하는 세계 여러나라의 잉어 생산량은 약 $18\;-\;l37g{\cdot}m^{-2}year^{-1}$이다. 3차연못 잉어생산량은 $125\;g{\cdot}m^{-2}year^{-1}$로 아주 양호한 생산량이다. 산업폐수가 유입되지 않은 생활하수나 축산폐수의 처리수를 이용한 양어의 고기는 생체실험결과 인체에 해가 없다고 규명되어 왔다.$^{15,16),17)$ 축산폐수를 자연생태적으로 처리하는 연못시스템의 연못에서 잉어를 사육할 경우 연못의 수질이 2차처리수준인 $BOD_5\;20\;mg{\cdot}L^{-1}$ 정도를 유지하는 것이 적절하다고 사료된다. 연못시스템은 축산지수를 효율적으로 처리할 수 있을 뿐만 아니라, 양어의 수확으로 축산농가의 소득증대에도 기여할 수 있다.