촉조된 습지 (wetland) 톨 이용한 때수처리의 설계기준에 관한 연구

윤춘경(Chun-Gyeong Yoon),정재춘(Jae-Chun Chung) 유기성자원학회 1996 유기물자원화 Vol.4 No.1

최근 축조된 습지를 이용한 폐수처리에 대한 관심이 높아지고 있다. 이는 습지이용시스탬이 자연정화법을 이용한 처리법으로써 에너지의 소모량이 적고 유지관리가 비교적 간단하며 기술적 난점이 적기 때문으로 판단된다. 그래서 이러한 시스댐은 우리나라 농촌지역에서 특히 응용될 수 있는 처리법이라고 생각된다. 본논문에서는 이러한 처리법을 우리나라에서 적용할 수 있도록 미국 둥 구미선진국에서 개발된 축소형 습지에 대한 설계기준에 대해서 논하였다. 본 논문에서 중점적으로 논한 것은 식생의 종류,자연적 천이와 관리,식재기법,파종기법 및 건설 후의 관리이다. Recently, significant attention is given to the wastewater treatment using Constructed wetland. This 'is because the wetland system is a kind of natural taeatment system, simple to maintain and it has relatively fewer technical difficulty. Thus, it would be a practical method to employ especially in rural area in Korea. 1n this paper, the authors dscuss the design criteria of construted wetland developed in USA as an initial feasibility study to adopt it in Korea. We discuss about especially types of vegetation, natural succession and management, planting techniques, seeding teckniques and management after censtruction.

농업용저수지 유역의 토지 이용과 수질항목 간의 상관관계 분석

윤춘경 ( Chun Gyeong Yoon ),이새봄 ( Sae Bom Lee ),정광욱 ( Kwang Wook Jung ),한정윤 ( Jung Yoon Han ) 한국하천호수학회 2007 생태와 환경 Vol.40 No.1

강물의 수질오염 Modeling에 사용되는 신뢰도 분석방법에 대한 비교연구

윤춘경 ( Yoon Chun Gyeong ) 한국농공학회 1995 韓國農工學會誌 : 전원과 자원 Vol.37 No.5

공학분야에 널리 사용되고 있는 신뢰도 분석방법중에서 Monte Carlo simulation (MC), Mean-value First-Order Second-Moment Method(MFOSM), and Advanced First-Order Second-Moment(AFOSM) method들을 강물의 오염물질 농도와 수질기준치사이의 신뢰도 분석에 적용하였다. 미환경보건국에서 개발 보급한 QUAL2E를 이용하여 New Jersey에 위치한 Passaic강의 수질예측에서 4가지 주요인자(용존산소, 생물학적 산소요구량, 암모니아 그리고 조류)들이 정해진 수질기준치를 유지 할 수 있는 확률을 세가지 방법에 의해 추정한 후에 상호 비교하였다. MC방법에 의해 2,000회 simulation시켜서 그 결과가 시스템의 추계학적 성질을 잘 반영한 것으로 판단하여 비교기준으로 삼고 MFOSM과 AFOSM에 의해 추정한 결과와 비교하였다. MFOSM의 결과보다는 AFOSM의 결과가 전체적으로 MC의 결과에 더 근접하였으며, 이유는 AFOSM의 계산방법이 MFOSM의 선형근사로 인한 오차를 줄일 수 있었기 때문인 것으로 판단된다. MC방법의 결과와 다른 방법들의 결과사이의 차이가 입력변수들이 평균값에서 멀어질 때가 많았는데 이는 MC의 경우 입력변수들이 일정범위를 벗어나서 비현실적인 상황이면 model이 정지하는데, 다른 방법들은 simulation에 의한 것이 아니고 수학적인 계산에 의해서 신뢰도가 추정되기 때문에 이러한 상황이 반영될 수 없기 때문이다. 강물의 수질을 취급하는 공학적인 측면에서 보면, 이중에 가장 간편한 MFOSM이 많은 simulation이 필요한 MC나 계산방법이 상대적으로 복잡한 AFOSM에 비해 오차가 크지 않아서 이들을 대신하여 사용될 수 있다고 판단된다.

오수처리수 관개 벼재배를 통한 농업용수 수질기준의 검토

윤춘경 ( Yoon Chun Gyeong ),권순국 ( Kwun Soon Kuk ),정일민 ( Chung Il Min ),권태영 ( Kwon Tae Young ) 한국농공학회 1999 韓國農工學會誌 : 전원과 자원 Vol.41 No.2

Agricultural water quality standards were reviewed through rice culture using treated sewage irrigation. The sewage from school building of Konkuk University was treated by a constructed wetland system, and the effluent of the system was irrigated for rice culture after nutrient concentration adjusted by dilution. Average concentration of COD, SS, T-N and T-P in irrigated water was 22.3mg/ ℓ, 6.5mg/ ℓ, 25.8mg/ ℓ, and 2.2mg/ ℓ, respectively. Treatment include irrigation of adjusted effluent with conventional fertilization (TWCF), adjusted effluent with no fertilization (TWNF). and effluent of the wetland system as it was with no fertilization (SWNF). These treatment plots were compared with control plot irrigated by tap water with conventional fertilization (CONTROL). Other environments for rice culture were identical for all the plots. Among them, TWCF showed the best growth rate and the highest yield, and constituents in the harvested rice showed not much difference among them. Which implies that irrigation with relatively high nutrient concentration compared to the current water quality standards may cause no adverse effect on rice culture and could be even beneficial. Although T-N for this study was 25 times greater than the current standards, rice culture was not adversely affected by irrigation water quality and even better results were observed than the CONTROL. It could be mistakenly that clean irrigation water produces better agricultural product, however, it is not necessarily true. Irrigation water with moderate nutrient concentration can enhance the plant growth, and better result might be expected. Therefore, peer review and modification if necessary are needed to the current agricultural water quality standards, especially for the nutrient components.

습지-연못 연계시스템에 의한 수질개선과 농업적 재이용 타당성 분석

윤춘경 ( Chun Gyeong Yoon ),장재호 ( Jae Ho Jang ),정광욱 ( Kwang Wook Jung ),함종화 ( Jong Hwa Ham ) 한국하천호수학회 2004 생태와 환경 Vol.37 No.3

A pilot study was performed from September 2000 to April 2004 to examine the feasibility of the wetland-pond system for the agricultural reuse of reclaimed water. The wetland system was a subsurface flow type, with a hydraulic residence time of 3.5 days, and the subsequent pond was 8 m3 in volume (2 m × 2 m × 2 m) and operated with intermittent-discharge and continuous flow types. The wetland system was effective in treating the sewage; median removal efficiencies of BOD5 and TSS were above 70.0%, with mean effluent concentrations of 27.1 and 16.8 mg L^(-1), respectively, for these constituents. However, they did often exceed the effluent water quality standards of 20 mg L^(-1). Removal of T-N and T-P was relatively less effective and mean effluent concentrations were approximately 103.2 and 7.2 mg L^(-1), respectively. The wetland system demonstrated high removal rate (92? 96%) of microorganisms, but effluent concentrations were in the range of 300? 16,000 MPN 100 mL^(-1) which is still high for agricultural reuse. The subsequent pond system provided further treatment of the wetland effluent, and especially additional microorganisms removal in addition to wetland-pond system could reduce the mean concentration to 1,000 MPN 100 mL^(-1) from about 106 MPN 100 mL^(-1) of wetland influent. Other parameters in the pond system showed seasonal variation, and the upper layer of the pond water column became remarkably clear immediately after ice melt. Overall, the wetland system was found to be adequate for treating sewage with stable removal efficiency, and the subsequent pond was effective for further polishing. This study concerned agricultural reuse of reclaimed water using natural systems. Considering stable performance and effective removal of bacterial indicators as well as other water quality parameters, low maintenance, and cost-effectiveness, wetland-pond system was thought to be an effective and feasible alternative for agricultural reuse of reclaimed water in rural area.

수도재배시 논에서의 영양물질 수지 분석

윤춘경 ( Chun Gyeong Yoon ),황하선 ( Ha Sun Hwang ),전지홍 ( Ji Hong Jeon ),함종화 ( Jong Hwa Ham ) 한국하천호수학회 2003 생태와 환경 Vol.36 No.1

Field experimental study was performed to evaluate water and nutrient balances in paddy rice culture. The water balance showed that outflow generally balanced the inflow showing that about half(47~54%) of total outflow was lost by surface drainage. No significant effect of fertilization rate was observed from three treatments (150%, 100%, and 70% of standard fertilization) on both rice yield and nutrient outflow from surface drainage. Therefore, reducing nonpoint source nutrient loading by reducing fertilization may not work well in the range of normal paddy rice farming practice, and instead it could be achieved by reducing surface drainage outflow. Water-saving irrigation by reducing ponding depth, raising ridge height in rice field, and minimizing forced surface drainage are suggested to reduce surface drainage outflow. These practices can save water and protect water quality, however, deviation from conventional standard practices might affect the rice yield and further investigations are necessary. It was demonstrated that rainfall affects nutrient net outflow and paddy rice culture might be beneficial to water quality protection under normal rainfall condition.

TDR을 이용한 토양함수비 측정의 정확성에 대한 실험

윤춘경 ( Yoon Chun Gyeong ),유찬 ( Yu Chan ),김경한 ( Kim Kyoung Han ) 한국농공학회 1999 韓國農工學會誌 : 전원과 자원 Vol.41 No.1

Laboratory experiment was performed for the TDR to measure the soil moisture, and the results, were compared with the design water content and the one measured by oven-try method. Sand and kaolinite were used. Variables for the experiment were water content (10~50%), void ration (0.7~1.3), mixture rate of kaolinite (10~30%), and measurement methods (TDR and oven-dry). In all cases, TDR method showed very accurate and reliable results, and average error and error range were far less than the oven-dry method which is widely used. Considerable error was noticed when water content was 50% where saturation was achieved for both methods. Therefore, TDR was thought to be applicable to the field moisture measurement if it is unsaturated. For field scale application of TDR, more research and verification of the accuracy with diverse soil conditions including physical, chemical and mineral properties are recommended.

강물의 수질오염 modeling에 사용되는 재폭기(再曝氣)계수공식 개발을 위한 적정규모의 표본의 크기

윤춘경 ( Yoon Chun Gyeong ),( Charles S. Melching ) 한국농공학회 1996 韓國農工學會誌 : 전원과 자원 Vol.38 No.4

동일한 하천의 용전산소량(DO)을 예측하는 경우에도 사용하는 再曝氣 계수(K₂)는 계산하는 공식에 따라 커다란 차이를 나타매며, 부적합한 공식의 사용에 의한 K₂의 계산은 하천의 수질관리 정책결정에 지장을 초래하므로 현장사정에 적합한 공식의 개발이 필요하다. 이러한 공식의 개발은 많은 현장측정 자료를 사용하도록 신뢰성이 높으나 현장측정은 소요되는 비용에 제약을 받기 때문에 신뢰성과 경제성을 동시에 고려한 표본의 크기의 적정규모를 산정하는 것이 필요하다. 본 연구에서는 Monte Carlo 방법에 의해 통계적으로 수출된 K₂를 사용해서, 주어진 자료에 의해 개발된 공식을 사용할 때 야기되는 오차가 K₂ 개수의 증가에 따라 얼마나 감소하는지를 널리 사용되는 공식 중에 Owen공식과 Churchill공식을 New Jersey에 있는 Passaic River에 적용시켜 검토하였다. 표본의 크기가 10에서 20으로 증가할 때 오차가 크게 감소하였으며 20을 넘어 증가시켰을 때에는 오차의 감소폭이 미미하였다. 오차의 감호형태와 단위측정당 소요되는 비용을 고려할 때 약 20정도의 표본의 크기가 적정수준의 규모에 판단된다. 이러한 적용사례의 결과는 회귀모델의 이론적 계산결과에 의한 오차 감소와 흡사하여 본 연구결과는 여러 가지 K₂ 공식과 광범위한 하천의 조건에 적용이 가능할 것이며, 본 연구에서 사용한 적정표본의 크기 산정방법은 회귀분석에 의해 실험식을 개발하는 다른 분야에도 적용이 가능하다.

습지-저류지에 의한 하구 담수호 수질개선 효과 예측

윤춘경 ( Yoon Chun Gyeong ),함종화 ( Ham Jong Hwa ) 한국농공학회 2000 韓國農工學會誌 : 전원과 자원 Vol.42 No.5

Investigated was the effectiveness of a constructed wetland system on water quality in Hwa-Ong estuarine reservoir, located in Hwasung-Gun, Kyunggi-Do. Procedures for estimation of pollutant loading from watershed and required area for natural systems, and simulation of corresponding reservoir water quality were reviewed. Generally, simulated reservoir water quality was within the reasonable range, and about 15% of total polder farmland was required to meet the agricultural water quality standards. The model was applied based on the current loading condition without additional treatment systems. Wetland system is an ecologically sound treatment system. Therefore, natural systems can be an alternative measure for water quality improvement in polder projects. The area for natural systems was estimated using literature value which might be acceptable at the planning stage. However, pilot system and its experimental data are requisite for large scale field application. WASP5 was proved to be a useful and versatile model, and its application to estuarine reservoir water quality simulation was thought to be appropriate.

용수재이용을 위한 하수처리 유출수의 UV 소독 효율 연구

윤춘경 ( Chun G. Yoon ),정광욱 ( Kwang Wook Jung ),함종화 ( Jong Hwa Ham ),전지홍 ( Ji Hong Jeon ) 한국농공학회 2003 韓國農工學會誌 : 전원과 자원 Vol.45 No.2

The feasibility study of UV-disinfection system was performed for disinfection of effluent from wastewater treatment plant. Three low-pressure UV lamps of 17, 25, and 41 W were examined with various flow rates. Low-pressure UV lamps of 17W were examined with various turbidity, DOM (dissolved organic matter), and SS (suspended solid). The pilot plant was a flow-through type UV-disinfection system, and the range of exposure time varied from 5 to 40 seconds, turbidity from 0 to 40 NTU, DOM from 0 to 30 mg/L, and SS from 10 to 40 mg/L. The 41W lamp demonstrated complete disinfection showing no survival ratio in all the experimental conditions, and generally 17W and 25W lamps also showed high removal ratio over 97%. For the same UV dose (UV intensity times exposure time), high intensity-short exposure conditions showed better disinfection efficiency than low intensity-long exposure conditions. While the effects of turbidity and DOM were not apparent, the effects of SS was significant on the disinfection efficiency which indicates that SS control before UV-disinfection appears to be necessary to increase removal efficiency. Considering characteristics of effluent from existing wastewater treatment plants, cost-effectiveness, stable performance, and minimum maintenance, the flow-through type UV-disinfection system with high intensity and low-pressure lamps was thought to be a competitive disinfection system for wastewater reclamation.