자유수면형 인공습지에서 식물식재 유무가 처리효율에 미치는 영향

함종화,김형중,김동환,홍대벽,Ham, Jong-Hwa,Kim, Hyung-Joong,Kim, Dong-Hwan,Hong, Dae-Byuk 한국농공학회 2011 한국농공학회논문집 Vol.53 No.6

Three different types of wetlands (unplanted wetland, reed planted wetland, cattail planted wetland) were constructed at the mouth of Seokmoon reservoir with 910 $m^2$ each to examine the effects of wetland plant on pollutant removal rate in constructed wetland, and operated for 9 years (2002~2010). Water depth of the wetland was maintained at 0.3~0.5 m, flow rate was about 40~200 $m^3$/day, and retention time was managed at about 1~5 days. There was no difference in removal rate of SS, TN, and TP between reed wetland and cattail wetland. Removal rate of SS and TN in planted wetland with reed and cattail were higher than unplanted wetland, whereas removal rate of TP in unplanted wetland was higher then planted wetland. The monthly variation of removal rate in planted wetlands was high compared with unplanted wetland. From the long term monitoring results, SS and TN removal rates of period3 (2008~2010) were higher than period1 (2002~2004) in planted wetland, whereas TP removal rate was decreased as time goes on. Overall, pollutant removal rate in constructed wetland was more influenced by existence of plants than by plant species. Although constructed wetland is operated long term period, SS, TN, and TP removal rate (SS 90 %, TN 60 %, TP 40 %) can be maintained high values.

물리적 설계인자가 인공습지의 처리효율에 미치는 영향

함종화,윤춘경,구원석,김형철,신현범,Ham Jong-Hwa,Yoon Chun G.,Koo Won-Seok,Kim Hyung-Chul,Shin Hyum-Bhum 한국농공학회 2005 한국농공학회논문집 Vol.47 No.5

The field scale experiment was performed to examine the effect of physical design parameters on the constructed wetland performance and recommend the feasible design of constructed wetland in Korean polder areas. Four sets (each set of 0.85 ha) of wetland (0.8 ha) and pond (0.08 ha) systems were used. Two different wetland systems, a wetland-pond system and a pond-wetland system, were studied to examine the effect of wetland and pond configuration. And two different length-to-width ratios were used, 2: 1 and 0.8: 1, to examine the effect of aspect ratio. A pond-wetland system was more preferable than a wetland-pond system, and also requires a smaller area than a wetland-pond system or a wetland system to reduce T-P. There was no difference in effluent concentration between the 2:1 system and the 0.8:1 system. Although the linear velocity of the 2:1 aspect was higher than the 0.8:1 aspect, resuspension was not a factor in this study due to a very low linear velocity. From this study and other literature review, it was found that design method of paddy rice field could be applied and expanded to the design of constructed wetland in Korea. Further investigation for the detailed design parameters of constructed wetland needs be continued for design method of paddy rice to be applied in full scale.

인공습지를 이용한 하구담수호 유입하천수 수질개선 현장실험결과 분석

함종화,윤춘경,구원석,김형철,신현범,Ham, Jong-Hwa,Yoon, Chun-G.,Koo, Won-Seok,Kim, Hyung-Chul,Shin, Hyun-Bhum 한국농공학회 2004 한국농공학회논문집 Vol.46 No.5

Wetland system is widely accepted as one of natural water purification systems around the world for nonpoint sources pollution control. Constructed wetlands have become a popular technology for treating contaminated surface and waste water. In this study, the field experiment to reduce nonpoint source pollution loadings from polluted stream waters using wetland system was performed from June 2002 to March 2004. Four wetlands were used and the size of each one was 0.8ha. Water of Dangjin stream flowing into Seokmun estuarine reservoir was pumped into wetlands. Inflow and hydraulic residence time of the system was 500 $m^3$/day∼1,500 $m^3$/day, 2∼5 days, respectively. After 2 year operation, plant-coverage of the wetlauds was about 70% from bare soil surface at initial stage . Average water quality of the influent was $BOD_5$ 4.17 mg/L, TSS 18.45 mg/L, T-N 4.32 mg/L, and T-P 0.30 mg/L. The average removal rate of $BOD_5$, TSS, T-N and T-P during the study period was 5.6%, 46.6%, 45.7%, and 54.8%, respectively. Organic ($BOD_5$) removal rate was low and the reason might be low influent concentration. Wetland removal rate of T-P was about 10% higher than T-N. Performance of the experimental system was compared with existing data base (NADB), and it was within the range of general system performance. Overall, the wetland system was found to be adequate for treating polluted water stream with stable removal efficiency even during the winter period. Most of the nonpoint source pollutions from watershed are transported by streams or ditches, and they could be controled by constructed wetland system before entering the lake or reservoir.

불확실성을 고려한 통합유역모델링

함종화,윤춘경,다니엘 라욱스,Ham, Jong-Hwa,Yoon, Chun-Gyoung,Loucks, Daniel P. 한국농공학회 2007 한국농공학회논문집 Vol.49 No.4

The uncertainty in water quality model predictions is inevitably high due to natural stochasticity, model uncertainty, and parameter uncertainty. An integrated modeling system under uncertainty was described and demonstrated for use in watershed management and receiving-water quality prediction. A watershed model (HSPF), a receiving water quality model (WASP), and a wetland model (NPS-WET) were incorporated into an integrated modeling system (modified-BASINS) and applied to the Hwaseong Reservoir watershed. Reservoir water quality was predicted using the calibrated integrated modeling system, and the deterministic integrated modeling output was useful for estimating mean water quality given future watershed conditions and assessing the spatial distribution of pollutant loads. A Monte Carlo simulation was used to investigate the effect of various uncertainties on output prediction. Without pollution control measures in the watershed, the concentrations of total nitrogen (T-N) and total phosphorous (T-P) in the Hwaseong Reservoir, considering uncertainty, would be less than about 4.8 and 0.26 mg 4.8 and 0.26 mg $L^{-1}$, respectively, with 95% confidence. The effects of two watershed management practices, a wastewater treatment plant (WWTP) and a constructed wetland (WETLAND), were evaluated. The combined scenario (WWTP + WETLAND) was the most effective at improving reservoir water quality, bringing concentrations of T-N and T-P in the Hwaseong Reservoir to less than 3.54 and 0.15 mg ${L^{-1}$, 26.7 and 42.9% improvements, respectively, with 95% confidence. Overall, the Monte Carlo simulation in the integrated modeling system was practical for estimating uncertainty and reliable in water quality prediction. The approach described here may allow decisions to be made based on probability and level of risk, and its application is recommended.

자유수면형 인공습지에 의한 저농도 고유량의 하천수질개선 효과 분석

함종화,윤춘경,구원석,김형철,신현범,Ham, Jong-Hwa,Yoon, Chun G.,Koo, Won-Seck,Kim, Hyung-Chul,Shin, Hyum-Bhum 한국농공학회 2005 한국농공학회논문집 Vol.47 No.1

Wetland systems are widely accepted natural water purification systems around the world in nonpoint sources pollution control. Constructed wetlands have become a popular technology for treating contaminated surface and wastewater. In this study, the field experiment to reduce nonpoint source pollution loadings from polluted stream waters using wetland system was performed from June 2002 to March 2004, including winter performance using four newly constructed wetlands. The Dangjin stream water flowing into Seokmun estuarine lake was pumped into wetlands, and inflow and hydraulic residence time of the system was $500m^{3}{\~}1500m^{3}/day\;and\;2{\~}5$ days respectively. After 3 years operation plant-coverage was about $80~90\%$ from zero at initial stage even with no plantation. Average water quality of the influent in growing season was BOD_{5}\;3.96mg/L$, TSS 22.98 mg/L, T-N 3.29 mg/L, T-P 0.30 mg/L. The average removal rate of four wetlands for $BOD_{5},\;TSS,\;T-N\;and\;T-P$ in growing season was $24\%$, $62\%$, $54\%$, and $51\%$, respectively. And average water quality of the influent in winter season was $BOD_{5}$ 4.92 mg/L, TSS 12.47 mg/L, T-N 5.54 mg/L, and T-P 0.32 mg/L, respectively. The average removal rate of four wetlands for them was $-21\%$. $23\%$, $33\%$, and $53\%$, respectively. The reason of higher BOD_{5} effluent concentration in winter season might be that low temperature restrained microorganism activity and a organic body from the withered plant and algae was flown out. Except the result of $BOD_{5}$, the effectiveness of water quality improvement in winter season was satisfactory for treating polluted stream waters, and $BOD_{5}$ variation was within the range of background concentration. Performance of the experimental system was compared with existing data base (NADB), and it was within the range of general system performance. Overall, the wetland system was found to be satisfactory for NPS control such as improvement of polluted stream water.

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.

SWMM 과 희귀분석법에 의한 유역의 오염부하량 산정 비교

윤춘경(Chun Gyeong Yoon),전지홍(Ji Hong Jeon),함종화(Jong Hwa Ham) 한국물환경학회 2001 한국물환경학회지 Vol.17 No.2

Rating curve method and SWMM (Storm Water Management Model) were applied to estimate pollution loading from Hwa-Ong watershed in Kyunggi-Do. Sampling data from monitored sites were used to derive rating curves and calibrate SWMM, and they were applied to the whole watershed including non-monitored subcatchments. Overall, the results from these methods were comparable and the loadings were in the same range and the difference was acceptable considering complicated natural pollutant loading processes. However, inconsistency was observed among the subcatchments. The pollutant loading estimates from two subcatchments with similar area were almost identical in rating curve methods, while the difference was significant in SWMM methods. Rating curve method can be a reliable tool to estimate pollutant loading from watershed if it is fully monitored, but it may generate large error during extrapolation to non-monitored area. SWMM is a comprehensive hydrologic model with great diversity that it can incorporate watershed characteristics like land use effects which is not available in rating curve methods. Therefore, it is recommended to use reasonable watershed model rather than rating curve and unit loading methods for the estimation of pollutant loading from watershed

비점오염원 제어를 위한 인공습지의 계절별 처리효율 비교

함종화 ( Jong Hwa Ham ),윤춘경 ( Chun Gyeong Yoon ),구원석 ( Won Seok Koo ),김형철 ( Hyung Chul Kim ),이광식 ( Kwang Sik Lee ) 한국물환경학회 2004 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2004 No.-

습지와 유수지를 이용한 강우 유출수 처리

함종화 ( Ham Jong Hwa ),윤춘경 ( Yoon Chun Gyeong ),구원석 ( Koo Won Suk ) 한국농공학회 2003 한국농공학회 학술대회초록집 Vol.2003 No.-

Constructed wetlands have become a popular technology for treating contaminated surface and wastewater. In this study, the field experiment to reduce nonpoint source pollution from watershed runoff during rainy day using wetland and pond. TSS and T-N removal rate of wetland-pond system and pond-wetland system was 91% and 73%, 94% and 70%, respectively and values were same range. BOD₅ and T-P removal rate of pond-wetland system (38% and 78%) was higher than wetland-pond system (27% and 62%). overall, pond-wetland system is more useful than wetland-pond system to control NPS

습지와 유수지를 이용한 하구담수호 수질개선

함종화 ( Ham Jong Hwa ),윤춘경 ( Yoon Chun Gyeong ),문용현 ( Moon Yong Hyun ) 한국농공학회 2002 한국농공학회 학술대회초록집 Vol.2002 No.-

Wetland systems are widely accepted natural water purification systems around the world in nonpoint sources pollution control. In this study, the field experiment to reduce nonpoint source pollution loadings from agricultural drainage and polluted stream waters using wetland and pond system was performed. The removal rate of BOD₅, TSS, TN, TP, and Chl-α was 52%, 90%, 56%, 59%, and 81%, respectively. Performance of the experimental system was compared with existing data base (NADB), and it was within the range of general system performance. Overall the water quality improvement was apparent in wetland and pond system.