The objectives of this study were to characterize an algae polluted-lake water using conventional variables of Trophic State Index Korea (TSIko) and to evaluate the performances of granular activated carbon (GAC) adsorption and the filtration of membrane filter (MF) using stirred dead end filtration cell on pollutants removal (COD, T-N, T-P, chlorophyll-a (chl-a), secchi disc (SD), and dissolved organic matter(DOC)) in the algae-polluted-lake water. As a result, regression analyses of log transformed seasonal Chl-a against T-P and T-N showed that variation of the Chl-a was explained by the variation of T-P(r= 0.3887) but not by T-N(r=0.2721). Consequently, The data obtained from this study suggest that one of the ways controlling the eutrophication would be a reduction of phosphorus from the watershed. Applied filtration rates during this experiment were <4.0 m/h for GAC bed and 0.5 m3/m2.d for MF. Both GAC bed and GAC/MF system achieved more than 40% efficiency in removing geosmin and 2-methylisoborneol(2-MIB). The combined membrane process with GAC adsorption process was found to produce the highest quality finished water and could be proposed as one of the best available processes for removing geosmin. The increase of influent algae and DOC increased transmembrane pressure (TMP) of MF process. Membrane resistance of MF process coupled with GAC bed was lower than that MF process.

Nickel is a widely used chemical species, but it is also known for its toxicity. The Pourbaix diagrams were constructed to investigate the influences of temperature and hydrogen ion on wastewater which contains nickel ion. Nickel exists as Ni3O4, Ni(OH)2, Ni2+, and Ni in the water of pH 0 to 14. In the temperature range of 288K to 318K, Ni(OH)2 was shown to have stable region from pH 5.7 to pH 14, and the area of stable region increases with temperature. The ratio of Ni(OH)2 to Ni and the ratio of Ni(OH)2 to Ni2+ wereexamined to be greater than the ratios of Ni3O4 to Ni and Ni3O4 to Ni2+, respectively. Also, the ratio of Ni(OH)2 to Ni2+ and the ratio of Ni3O4 to Ni2+ were shown to be proportional to the temperature, while Ni was not. The reduction-precipitation process of nickel ion to Ni(OH)2 by controlling the pH depending on the temperature following the value of pH 6.29 at 288K, pH 6.08 at 298K, pH 5.88 at 308K, and pH 5.70 at 318K, can be used to decrease concentration of nickel ion in wastewater and recover nickel from wastewater in the form of Ni(OH)2.

In this study, economical and efficient sewage and wastewater treatment methods were analyzed by distributing sewage flowing into the public wastewater treatment facility from the residential area of Dalseong 1st industrial complex to nearby sewage and wastewater treatment facilities. In the future, it was attempted to predict the increase in the amount of wastewater by industry by analyzing the change trend by industry within the Dalseong 1st Industrial Complex. Therefore, the environmental infrastructure around the Dalseong 1st Industrial Complex with the possibility of linked treatment was investigated. Based on this, the Hyeonpung Sewage Treatment Plant was judged to be suitable in consideration of various legal considerations such as the flow rate of each facility and effluent water quality standards. The distance from the public wastewater treatment facility in the Dalseong Industrial Complex to the Hyeonpung sewage treatment plant, the diameter of the pipe, and the type of pipe were reviewed, and the total project cost was more than KRW 2.8 billion. The Dalseong 1st Industrial Complex treats both sewage from residential areas and wastewater from industrial complexes, and the Hyeonpung Sewage Treatment Plant selected as the linked treatment area is a sewage treatment plant. Therefore, it is judged that the administrative procedure for changing the residential area of the Dalseong 1st Industrial Complex from a public wastewater treatment plant to a sewage treatment plant and consultation with related organizations is necessary.