김용석 Yong Seok Kim , 박재홍 Jae Hong Park , 박지형 Ji Hyoung Park , 박배경 Bae Kyung Park , 어성욱 Seong Wook Oa

DOI:10.15681/KSWE.2015.31.3.235 Vol.31(No.3) 235-240, 2015

To evaluate the unit load generation and discharge, pig cage test was conducted. Feed intake, drink amount, and urine generation increased growth stage (heavy weight) of the pig more great. However, the sum of the urine and manure did not show a significant difference in the growth stages of pigs. Because of the limit of the experiment, e.g., research period, high pigpen temperature, breed-related stress and etc., it could not be derived the results of the four seasons. Therefore, in order to generalize the results, the feed intakes were calibrated using a NRC (National Research and nutritional requirements of pigs from the Commission) standards. The finalized unit load generation and generation amounts of manure and urine were estimated at BOD 104.1 g/head/d, T-N 21.2 g/head/d, T-P 4.9 g/head/d, manure 0.96 L/d, urine 1.66 L/d with consideration of revised feed intake. Compare to the former research results of MOE (Ministry of Environment, 1999) and NIAS (National Institute of Animal Science, 2008), the generation amounts of manure and urine were similar to the NIAS’s values. In case of unit load generation, BOD and T-N were almost similar in all of them. However, the T-P unit load generation of MOE was more difference, e.g., 2.5 times high, compare to this study.

Cage test, Swine wastewater, TOC, Unit loads generation

금동혁 Dong Hyuk Kum , 박윤식 Youn Sik Park , 정영훈 Young Hun Jung , 신민환 Min Hwan Shin , 류지철 Ji Chul Ryu , 박지형 Ji Hyung Park , 양재의 Jae E Yang , 임경재 Kyoung Jae Lim

DOI:10.15681/KSWE.2015.31.3.241 Vol.31(No.3) 241-252, 2015

Runoff behaviors by five bias correction methods were analyzed, which were Change Factor methods using past observed and estimated data by the estimation scenario with average annual calibration factor (CF_Y) or with average monthly calibration factor (CF_M), Quantile Mapping methods using past observed and estimated data considering cumulative distribution function for entire estimated data period (QM_E) or for dry and rainy season (QM_P), and Integrated method of CF_M+QM_E(CQ). The peak flow by CF_M and QM_P were twice as large as the measured peak flow, it was concluded that QM_P method has large uncertainty in monthly runoff estimation since the maximum precipitation by QM_P provided much difference to the other methods. The CQ method provided the precipitation amount, distribution, and frequency of the smallest differences to the observed data, compared to the other four methods. And the CQ method provided the rainfall-runoff behavior corresponding to the carbon dioxide emission scenario of SRES A1B. Climate change scenario with bias correction still contained uncertainty in accurate climate data generation. Therefore it is required to consider the trend of observed precipitation and the characteristics of bias correction methods so that the generated precipitation can be used properly in water resource management plan establishment.

Bias Correction, Change Factor, Climate Change Scenarios, Runoff, Quantile Mapping

박상진 Sang Jin Park , 이상혁 Sang Houck Lee

DOI:10.15681/KSWE.2015.31.3.253 Vol.31(No.3) 253-261, 2015

The purpose of this study is the efficient biological treatment of highly concentrated nitrate nitrogen by calcium ion control present within the pickling wastewater. In laboratory scale’s experiments research was performed using a sequencing batch reactor and the evaluation of denitrification reaction in accordance with the injection condition of calcium ions, the surface properties of microorganisms, and the evaluation of sludge precipitability were performed. Results of the study showed that the denitrification reaction was delayed when injecting more than 600 mg/L of the calcium ion within the denitrification process. In addition, we observed the absorption form of calcium ions absorbed on the surface of microorganisms following an increase in the calcium ion dose. It was found that as the calcium ion dose increased the sludge precipitability also increased continuously and it is judged that a smooth denitrification induction is possible when treating the nitrate nitrogen by the calcium ion control of pickling waste water and the shortening of precipitation time enables a liquid operation to increase the reaction time.

Acid pickling wastewater, Calcium, Nitrate, Sequencing batch reactor

박기수 Ki Soo Park , 청징 Jing Cheng , 김영철 Young Chul Kim

DOI:10.15681/KSWE.2015.31.3.262 Vol.31(No.3) 262-271, 2015

Laboratory study was undertaken to pursue the filter performance of a micro-filter module employing highly porous fiber media under a high filtration rate (over 1,500 m/day), faster than that of any conventional filter process. The effects of filtration rate, head loss, raw water turbidity, and filter aid chemicals on filter performance were analyzed. In spite of the extremely high filtration rate, the filter achieved an attractive efficiency, reducing the raw water turbidity by over 80%. As with other filter systems, the filter aid used (PAC in this study) greatly affected the performance of this particular fiber filter. Long term repetitive runs were additionally carried out to confirm the reproducibility of the filter performance. Finally, a comparison was carried out with other high rate filter systems which are either being tested for use in experimental studies, or are already commercially available.

Fiber media, High filtration rate, Micro-filter, Turbid water

이혁 Hyuk Lee , 강태구 Tae Gu Kang , 남기범 Gi Beom Nam , 하림 Rim Ha , 조경화 Kyung Hwa Cho

DOI:10.15681/KSWE.2015.31.3.272 Vol.31(No.3) 272-285, 2015

Accurate assessment of chlorophyll-a (Chl-a) concentrations in inland waters using remote sensing is challenging due to the optical complexity of case 2 waters. and the inherent optical properties (IOPs) of natural waters are the most significant factors affecting light propagation within water columns, and thus play indispensable roles on estimation of chl-a concentrations. Despite its importance, no IOPs retrieval model was specifically developed for inland water bodies, although significant efforts were made on oceanic inversion models. So we have applied and validated a recently developed Red-NIR three-band model and an IOPs Inversion Model for estimating Chl-a concentration and deriving inland water IOPs in Lake Uiam. Three band and IOPs based Chl-a estimation model accuracy was assessed with samples collected in different seasons. The results indicate that this models can be used to accurately retrieve Chl-a concentration and absorption coefficients. For all datasets the determination coefficients of the 3-band models versus Chl-a concentration ranged 0.65 and 0.88 and IOPs based model versus Chl-a concentration varied from 0.73 to 0.83 respectively. and Comparison between 3-band and IOPs based models showed significant performance with decrease of root mean square error from 18% to 33.6%. The results of this study provides the potential of effective methods for remote monitoring and water quality management in turbid inland water bodies using hyper-spectral remote sensing.

Chlorophyll-a Concentration, Inherent Optical Properties, IOPs, Inversion Model for Deriving IOPs, Red-NIR 3-band Model

박혜경 Hae-kyung Park , 신라영 Ra-young Shin , 이혜진 Hae Jin Lee , 이경락 Kyung-lak Lee , 천세억 Se-uk Cheon

DOI:10.15681/KSWE.2015.31.3.286 Vol.31(No.3) 286-294, 2015

Temporal and spatial characteristics of cyanobacterial communities at the monitoring stations for Harmful Algal Bloom Alert System (HABAS) in Nakdong River and Lake Dukdong were investigated for two years (2013 to 2014). A total of 30 cyanobacterial species from 14 genera were found at the survey stations. Microcystis sp. showed maximum cell density in the total cyanobacterial community in August, 2014 at ND-2 and in September, 2013 at ND-3 station. Lynbya limnetica and Geitlerinema sp., non-target species for alert criteria showed maximum cell density at ND-1 (August, 2013) and Dam station of Lake Dukdong (September, 2014), respectively. Total cyanobacterial cell density and the relative abundance of four target genera (Microcystis, Anabaena, Aphanizomenon and Oscillatoria spp.) for alert criteria was relatively lower in the mesotrophic Lake Dukdong than at the eutrophic riverine stations of Nakdong River, indicating cyanobacterial density and the RA of target genera is affected by the trophic state of the monitoring stations. Simulating the alert system using phycocyanin concentration as an alert criterion resulted in the longer period of alert issued compared to the period of alert issued using the current criterion of harmful cyanobacterial cell density due to the influence of phycocyanin concentration from non-target cyanobacterial species.

Cyanobacteria, Harmful Algal Bloom Alert System, HABAS, Lake Dukdong, Nakdong River, Phycocyaninconcentration

최인욱 In Uk Choi , 신동석 Dong Seok Shin , 김홍태 Hong Tae Kim , 박재홍 Jae Hong Park , 안기홍 Ki Hong Ahn , 김용석 Yong Seok Kim

DOI:10.15681/KSWE.2015.31.3.295 Vol.31(No.3) 295-303, 2015

In Korea, Total Maximum Daily Loads(TMDLs) has been enforced to restore and manage water quality in the watersheds. However, some assesment of implementation plan of TMDLs showed that the achievement of the target water quality is not related to the proper allocation loads because difference of flow duration interval. In the United States, the discharge loads are determined by water quality modeling considering standard flow conditions according to purpose. Therefore, this study tried to develop the allocation method considering economical efficiency using water quality model. For this purpose, several allocation methods being used in the management of TMDLs is investigated and develope an allocation criteria considering regional equality and uniformity. Since WARMF(Watershed Analysis Risk Management Framework) model can simulate thetime varying behavior of a system and the various water quality variables, it was selected for a decision support system in this study. This model showed fairly good performance by adequately simulating observed discharge and water quality in Miho watershed. Furthermore, the scenario simulation results showed that the effect of annual average water quality improvement to remove 1kg BOD is more than 25 times, even if point pollutants treatment facility is six times more expensive to operate than non-point pollutants treatment facility.

Allocation method, Dynamic model, Miho watershed, Optimized model, Total Maximum Daily Loads

김신 Shin Kim , 이규열 Kyu Yeol Lee , 김주언 Ju Eon Kim , 이권철 Kwon Chul Lee , 안정민 Jung Min Ahn , 이인정 In Jung Lee , 정강영 Kang Young Jung , 임태효 Tae Hyo Im

DOI:10.15681/KSWE.2015.31.3.304 Vol.31(No.3) 304-312, 2015

In this study, we tried to determine the vertical variation of sediment structure and geochemical characteristics, core sediment was collected in the Nakdong River midstream on August, 2014. Core sediment mainly composed of sand (51.48%) and silt (46.21%) and coarsing upward changed from sM to mS facies. IL and TOC were decreased from lower to upper layer. C/N ratio was lower than 10 so the organic matters were originated from underwater creatures and C/S ratio was decreased from lower to upper layer. Heavy metal (Al, Fe, Zn, Cr, Pb, Ni, Cu, Cd) content were decreased from lower to upper layer and seriously polluted condition is not. These results are thought to be due to the effect of natural and anthropogenic in the fluctuation of flow.

C/N ratio, Core sediment, C/S ratio, Heavy metal, Nakdong-River, Sedimentary structure

심무준 Moo Joon Shim , 이수형 Soo Hyung Lee

DOI:10.15681/KSWE.2015.31.3.313 Vol.31(No.3) 313-318, 2015

To study the influence of changes in river discharge on water quality of the main stem of the Geum River, we investigated variation of inflow load from tributaries with river discharge. We also studied the mixing behavior of pollutants during mixing of waters of the main stem and Gap Stream. For this study, we collected water quality data such as suspended solids (SS), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total organic carbon (TOC), total nitrogen (TN) and total phosphorus (TP) representing pre-monsoon, monsoon, and post-monsoon events of 2013 from a website of Water Information System. Based on inflow load, the Gap and Miho streams may be ones of tributaries which may largely influence water quality of main stem in upper river region. The Suksung and Nonsan Streams seemed to further affect water quality downstream. Results of modified EMMA indicated SS and TP may have another source(besides Gap Stream) at pre-monsoon, monsoon, and post-monsoon period. In contrast, TN and organic matter (BOD, COD, TOC) were conservative at pre-monsoon and post-monsoon. However, when river discharge increased, these pollutants may also came from unspecified non-point sources. Therefore, we need to attempt to find non-point sources for the pollutants in the main channel of upper Geum River region.

Gap Stream, River discharge, Tributary mixing, Water quality

노성유 Seong Yu Noh , 최희락 Hee Lak Choi , 박종영 Jong Young Park , 황순진 Soon Jin Hwang , 김상훈 Sang Hun Kim , 이재안 Jae An Lee

DOI:10.15681/KSWE.2015.31.3.319 Vol.31(No.3) 319-327, 2015

The present study was carried out to develop biological criteria for aquatic ecosystem health assessment using composition and diversity of collected species. The sampling sites were a total of 67 sites in the Han River (29 sites) and the Nakdong River (38 sites), May and September 2012. During the survey period fish were collected totally 93 species. In each water system, 73 and 61 species were collected in the Han River and the Nakdong River respectively. The current composition of fish species between the Han River and Nakdong River showed similar pattern. The dominant species was Zacco platypus of the Han River, and the Nakdong River was Opsariichthys uncirostris. In particular, ecological characteristics of O. uncirostris frequently appeared in general polluted waters. In conclusion, in the Nakdong River, average value of FAI (Fish Assessment Index) was averaged 41.3, indicating a “poor condition”, and the Han River was 53.1, indicating a “poor condition”. The aquatic health of the Nakdong River assessed based on FAI was considered to be worse than that of the Han River.

Ecological Health Assessment, FAI, Fish Assessment Index, Freshwater Fish, Han River, Nakdong River

최희정 Hee-jeong Choi

DOI:10.15681/KSWE.2015.31.3.328 Vol.31(No.3) 328-333, 2015

In this study, Mg-Sericite was used as a flocculant to harvest freshwater microalgae, Chlorella. vulgaris. Mg-Sericite separated successfully >95% of the C. vulgaris at the following optimal parameters: Mg/Si mol ratio 1.25 to 1.50, mixing time of 20 min and settling time of 20 min. The harvesting efficiency was pH dependent. The highest harvesting efficiency (99±0.3%) was obtained at Mg/Si mol ratio 1.5 and pH 9 to 11. These results indicated that a biopolymer, Mg-Sericite, can be a promising flocculant due to its high efficiency, low dose requirements, short mixing and settling times. This harvesting method is helpful to lower the production cost of algae for biodiesel.

Biomass, Clay, Flocculation, Harvesting, Microalgae, Mg-Sericite