전상호 , 이해금 Sang Ho Jun , Hae Keum Lee

DOI: Vol.2(No.2) 2001-2008, 1986

Pollution potential of bottom mud on overlying water quality at a site of Gongjichon area in Lake Uiam is investigated. The bottom mud is classified as bioturbated layer, sand layer, and reduced layer by texture, color, and organic activity. The bottom mud has high organic carbon content, low C/N ratio in bioturbated layer, little organic carbon content in sand layer, and moderate organic carbon content, high C/N ratio in reduced layer. This shows that fresh organic matter is accumulated in the bioturbated surface layer, and degradation of organic matter is more complete in the deeper part of the mud, and bioturbated layer has high pollution potential on overlying water.

이문호 , 서윤수 , 현용범 Mun Ho Lee , Yoon Soo Suh , Yong Bum Hyun

DOI: Vol.2(No.2) 2009-2013, 1986

The roles of algal biomass as a organic pollutant in the fresh water lakes was estimated and oxygen demand exerted by dead algal cells was determined. The results are as follows: Mean chlorophyll-a content of ATCC 4 strains, Anabaena, Scenedesmus, Microcystis, Cblorella, was 0.84% of dry weight and mean COD demanded by 1mg dry weight of algal biomass was 0.34mg. We could calculate algal COD (mg/1) from chlorophyll-a concentration (mg/m^3) in the lake water by multiplication by 0.04. The proportion of algal COD to the lake water COD was about 6.7% when the lake was in the normal state. But the proportion was increased by more than 30% during the season of algal bloom, accordingly algae contribute as a important organic pollutant in this season. BOD_5 and BOD_12 demanded by dead 1mg algal biomass of Anabaena flos-aquae were 1.3mg, 1.6mg respectively. With this respect algal biomass can be serve as a serious organic pollutant and can consume much oxygen in the lake especially during the death phase of algal bloom.

박영규 , 이철희 , 나중균 , 정병걸 Yung Kyu Park , Chul Hee Lee , Joong Kyun Ra , Byung Geul Chung

DOI: Vol.2(No.2) 2014-2024, 1986

Studies were carried out on the pathway and the trend of the heavy metal pollution on the sediment in the down stream of Nak-dong river. It was found that The content of heavy metal on sediment concentrated in the small particle size. The ratio of copper between 400 mesh and 230/270 mesh was to be 2.07 In the upper part of sediment and in the lower part of sediment to be 2.78. Copper pollution at each sampling sites was remarkably increased to the down stream. The coefficient variances of each heavy metal in the same particle size wire not different greatly, but the values of the coefficient variance between heavy metals showed different. The contents of organic matter in the small particle size were also more concentrated than the large particle size. The high correlation between organic matter and the content of heavy metal on the sediment could be found. If was confirmed that heavy metals such as Cu, Zn and Cr of sediment in the down stream of Nak-dong river were originated with pollution fly the analysis of the probability distribution and the coefficient variance.

양동범 , 이광우 Dong Beom Yang , Kwang Woo Lee

DOI: Vol.2(No.2) 2025-2030, 1986

Distributions of chemical oceanographic parameters were measured in Jindong Bay in July and September, 1982 and in July, 1983. In July, 1982, low concentrations of nutrients were observed in the surface waters of high salinity. In September, 1982, lowering of surface salinity accompanied an increase in nutrient concentrations which were too low for red-tide bloom. In July, 1983, although the sampling was done just after heavy rainfall, concentrations of dissolved inorganic nitrogen in the surface waters seemed to be not sufficient for red-tides to occur. And dissolved phosphate contents were over 20 ㎍p/ℓ in the surface waters, suggesting that phytoplankton growth was not limited by phosphates.

김치경 , 김근식 Chi Kyung Kim , Keun Sik Kim

DOI: Vol.2(No.2) 2031-2041, 1986

The survival of E.Coli was studied by an in situ method in water column, sediment, and water-sediment interface in Moosimcheon River waters. Their survival rates were analyzed in terms of ecological correlations with water temperature, water quality, and indigenous predators. E. coli survived longer in water-sediment interface than in water column, and shorter than in sediment. The survival rates increased in any samples as the water temperature decreased, while the difference of the rates in water column and sediment decreased in the colder season. In the samples of the more polluted waters, the organisms survived longer. The difference of the rates in water column and sediment was greater in the less polluted waters than in more polluted. The total numbers of indigenous predators were found to be about 1 log higher in sediment than in water column. But after 14 days of in situ experiment, the number in the dialysis sac changed to be 1 log higher in sediment than in water sample. The fact that the survival rates of E. coli in water-sediment interface were always higher than those in water column, and lower than those in sediment, without regard to water temperature, water quality and heterotrophic activity of E. coli in the waters. But the amount of sediment materials resuspending into the water column was found to be one of the most important factors for survival of E. coli in the river waters.

윤제용 , 김신조 , 임기철 , 김준용 Jae Yong Yoon , Shin Jo Kim , Ki Chul Lim , Joon Yong Kim

DOI: Vol.2(No.2) 2042-2053, 1986

The reaction of ferrite formation by aerial oxidation of Fe(OH)_2 suspension of aqueous solutions has been recognized as the convenient methods for the treatment of waste-water containing several kinds of heavy metal ions at high concentration. In this study the optimal conditions of the ferrite formation are studied by air oxidation of Fe(OH)_2 suspensions, which are subjected to various temperatures and time under the different kinds of R(=2NaOH/FeSO_4, 2NaOH/FeCl_2) values and heavy metal ions. The samples after ferrite process are then examined by X-Ray diffraction, electron microscopic observation, magnetic hysteresis loop tracer, and dissolving experiment, the concentrations of heavy metal ions in treated water are examined by A.A. spectroscopy.

이수환 , 정용 , 권숙표 Soo Hwan Lee , Yong Kwon Chung , Sook Pyo Kwon

DOI: Vol.2(No.2) 2054-2064, 1986

Hanging Biological Contactor process is utilized to sewage treatment by symbiosis and food-chain mechanism with micro-organisms adhered on hanging contactor in the biological reactor. Recently this process has been widely applied to organic wastewater and domestic sewage treatment in small size with the advantages of low cost for maintenance and simple operation. This study was dealt with organic removal efficiencies owing to the operation variables, such as flowrate of influent wastewater, the length of hanging contactor, organic loading rate, and degree of dissolved oxygen saturation, and organic removal efficiency in HBC process, and the following experimental results subsequently obtained; For the upmost BOD removal efficiency with respect to the retention time and air flow rate, BOD removal efficiency showed 84% to 12 hours of retention time and 3 1/min of air flow rate, 75% to 8 hours of retention time and 5 1/min of air flow rate, and 73.2% to 4 hours of retention time 9 1/min of air flow rate. When the length of hanging contactor in the reactor was 4m of above, the upmost BOD removal efficiency was shown in 85.9% and BOD removal rate constant (Ko) 0.056day^(-1). In this case, BOD loading rate with respect to 1m of hanging contactor was 3.04 g BOD/m/day. From the Stepwise Multiple Regression Analysis for the related parameters effected on BOD removal efficiency, using SPSS, the following equation was obtained; Y = 66.1 + 56.4x₁ + 0.34x₂ + 16.7x₃ - 15.6x₄ - 5.4x_5 + 0.29x_6 + 0.26x_7 - 0.24x_8 - 0.23x_9 (R^2 = 0.71, P<0.01) where; Y = EFF (Effluent BOD concentration, ㎎/ℓ) x₁ = INEL (Influent flow rate, ㎥/day) x₂ = ORLD (Influent organic loading, BODg/day) x₃ = RT (Retention time, hr) x₄ = RI (Length of HBC, m) x_5 = TEO (Influent water temperature, ℃) x_(6-9) = DO1-DO4: (DO saturation rate at stage 1-4, %)