Perfluorooctanoic acid (PFOA) and perfluorooctyl sulfonate (PFOS) is a new persistent organic pollutants of substantial environmental concern. This study investigated the potential of magnetic ion exchange resin (MIEXⓇ) as the adsorbent for the removal of PFOA and PFOS from Nakdong River water. In our batch experiments, we studied the effect of some parameters (pH, temperature, sulfate concentration) on the removal of PFOA and PFOS. The results of sorption kinetics on MIEXⓇ show that it takes 90 min to reach equilibrium but the economical contact time and dosage were 30 min and 10 mL/L. An increase in pH (pH 6∼10) leads to a decrease in PFOA (2.0%) and PFOS (3.6%) sorption on MIEXⓇ. The sorption of both PFOA and PFOS decreases with an increase in ionic strength for sulfate ion (SO4 2-), due to the competition phenomenon. An increase in water temperature (8℃∼28℃) in water leads to a increase in PFOA (2.8%) and PFOS (4.3%) sorption on MIEXⓇ. Based on the sorption behaviors and characteristics of the adsorbents and adsorbates, ion exchange and hydrophobic interaction were deduced to be involved in the sorption, and hemi-micelles possibly formed in the intraparticle pores.

We compared the applicability and economical efficiency of peroxone process with those of ozone process in the existing water treatment plant on downstream of Nakdong River. After comparing the peroxone process for removing geosmin with the ozone process in lab scale test, peroxone process showed much higher removal efficiency than the ozone process at the same ozone dosage. Proper range of H2O2/O3 ratio were 0.5~1.0 and the half-life of geosmin was about 5.5~6.8 min when the H2O2/O3 ratio was set to 0.5 during 1~2 mg/L of ozone dosage. Peroxone process could reduce the ozone dosage about 50 to maximum 30% for the same geosmin removal efficiency compared to the ozone process in the pilot scale test. In case of 1,4-dioxane treatment, peroxone process could have 3~4 times higher efficiency than ozone process at the same ozone dosage. The results of estimating the economical efficiency of ozone and peroxone process for treating geosmin and 1,4-dioxane by using pilot scale test, in case of the removal target was set to 85% for these two materials, the cost of peroxane process could be reduced about 1.5 times compared to ozone process, and in the same production cost peroxone process could have 2~3 times higher removal efficiency than ozone process. The removal efficiency by peroxone process showed a large difference depending on the physicochemical characteristics of target materials and raw water, therefore detailed examination should be carried out before appling peroxone process.

The Nakdong River being used as drinking water sources for the Busan metropolitan city has the vulnerability of water management due to the fact that industrial areas are located in the upper Nakdong River. This study used emergy analysis method to evaluate ecological-economics of water treatment systems of D water treatment plant (WTP) where located in the downstream of the Nakdong River. The emergy methodology is a system evaluation tool that uses energy as the common currency to compare different resources on a common basis. Emergy yield ratio (EYR) and emergy sustainability index (EmSI) of D WTP were 1.16 and 0.18, respectively. It means not resources and sustainable system but consumer goods and not sustainable system. Ratio of emergy benefit to the purchaser (EBP) shows 2.7 times higher than economic costs. To change the weak water source and situations we need to diversity water intake.

After identifying species by collecting the suspended and attached algae mat inhabiting in the slow sand-filter, Spirogyra sp., Mougeotia sp. and Closterium sp. were main green algae and Synedra sp. was diatom algae. Among them green algae Spirogyra sp. was dominant species. A result of observing the life mode of apple snail for a month after introducing into the slow sand-filter, apple snail eggs were discovered on the filter walls 2 weeks after introducing, 4 weeks later lots of eggs were observed all of the slow sand-filter walls, it means there is no problem for apple snail to live in the slow sand-filter. The observation result for algae removal potential by introduced apple snail after 2 months later, slow sand-filter where apple snail were introduced, a few algal mat were observed. On the other hand, no introduced apple snail into the slow sand-filter, lots of suspended algal mats were formed in the water and attached algal mats on the sand surface as well, these algal mat induced much of operating problems.

This is made of domestic and foreign coal activated carbon of five species, physicochemical adsorption efficient about sterilize products and micro harmful substances and is a result of the economic evaluation. The most well-developed micropores bed volume 123,409 of AC-1 activate carbon appeared to be the best next AC-2, AC-3, AC-4, AC-5 followed by activated carbon was investigated. PFOA and PFOS in the BV 96,000 when evaluating foreign types of adsorption activated carbon adsorption capacity was greater when more than PFOA, PFOS showed that the adsorption well. The economic evaluation of activated carbon usage in chloroform (CUR) was most excellent as a AC-1 4.3 g/day, the next AC-2, AC-3, AC-4, AC-5 there are two types of foreign economic order appears to have appeared, but the current domestic market when applying the price AC-1, AC-3, AC-2, AC-4, AC-5 order was investigated.

The concentration of organic compounds was analyzed at each step of BAC process though BDOCtotal/rapid/slow. Further, bacteria communities and biomass concentrations measured FISH and ATP methods were analyzed. The bed volume (BV) of steady state is different from that of based on assessment of organic compounds removal. Bed volumes in DOC, BDOCrapid and BDOCtotal/slow removal at steady state were around 27,500 (185.8 day), 15,000 (101.4 day) and 32,000 (216.2 day), respectively. A biomass didn't change after the bed volume reached 22,500 (152.0 day) according to analyzing ATP concentration of bacteria. The concentration of ATP was 2.14 μg/g in BV 22,500 (152.0 day). The total bacterial number was 4.01±0.4×107 cells/g at the bed volume 1,150 (7.8 day) (the initial operation) and the number of bacteria was 9.27±0.2×109 at the bed volume 58,560 395.7 day) that increased more than 200 times. Bacterial uptrend was reduced and bacterial communities were stabilized since BV 18,720 (126.5 day). When BV were 1,150 (7.8 day), 8,916 (60.2 day), 18,720 (126.5 day), 31,005 (209.5 day), 49,632 (335.3 day), 58,560 (395.7 day), a proportion of total bacteria for the Eubacteria were 60.1%, 66.0%, 78.4%, 82.0%, 81.3% respectively. γ-Proteobacteria group was the most population throughout the entire range. The correlation coefficient (r2) between Eubacteria biomass and ATP concentration was 0.9448.

The aims of this study were to investigate and confirm the occurrence and distribution patterns of iodinated X-ray contrast media (iopromide) in Nakdong river basin (mainstream and its tributaries). Iopromide was detected in 16 sampling sites. The concentration levels of iopromide on February 2011 and on October 2011 in surface water samples ranged from not detected (ND) to 1481.1 ng/L and ND to 1168.2 ng/L, respectively. The highest concentration level of iopromide in the mainstream and tributaries in Nakdong river were Goryeong and Jincheon-cheon, respectively. The sewage treatment plants (STPs) along the river affect the iopromide levels in river and the iopromide levels decreased with downstream because of dilution effects.

Formation of disinfection by-products (DBPs) including trihalomethans (THMs), haloacetic acid (HAAs), haloacetonitriles (HANs) and others from chlorination of algogenic organic matter (AOM) of Microcystis sp., a blue-green algae. AOM of Microcystis sp. exhibited a high potential for DBPs formation. HAAs formation potential was higher than THMs and HANs formation potential. The percentages of dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) formation potential were 43.4% and 51.4% in the total HAAs formation potential. In the case of HANs formation potential, percentage of dichloroacetonitrile (DCAN) formation potential was 97.7%. Other DBPs were aldehydes and nitriles such as acetaldehyde, methylene chloride, isobutyronitrile, cyclobutanecarbonitrile, pentanenitrile, benzaldehyde, propanal, 2-methyl, benzyl chloride, (2-chloroethyl)-benzene, benzyl nitrile, 2-probenenitrile and hexanal.

The aims of this study were to investigated the occurrence of caffeine and carbamazepine in Nakdong river basin (8 mainstreams and 2 tributaries) and the behavior of caffeine and carbamazepine under drinking water treatment processes (conventional and advanced processes). The examination results showed that caffeine was detected at all sampling sites (5.4 ∼558.5 ng/L), but carbamazepine was detected at five sampling sites (5.1∼79.4 ng/L). The highest concentration level of caffeine and carbamazepine in the mainstream and tributaries in Nakdong river were Goryeong and Jinchun-cheon, respectively. These pharmaceutical products were completely removed when they were subject to conventional plus advanced processes of drinking water treatment processes. Conventional processes of coagulation, sedimentation and sand-filtration were not effective for their removal, while advanced processes of ozonation and biological activated carbon (BAC) filtration were effective. Among these pharmaceuticals, carbamazeoine was more subject to ozonation than caffeine.

The Raw water from Deer Creek (DC) reservoir and Little Cottonwood Creek (LCC) reservoir in the Utah, USA were collected for jar test experiments. This study examined the removal of arsenic and turbidity by means of coagulation and flocculation processes using of aluminum sulfate and ferric chloride as coagulants for 13 jar tests. The jar tests were performed to determine the optimal pH range, alum concentration, ferric chloride concentration and polymer concentration for arsenic and turbidity removal. The results showed that a comparison was made between alum and ferric chloride as coagulant. Removal efficiency of arsenic and turbidity for alum (16 mg/L) of up to 79.6% and 90.3% at pH 6.5 respectively were observed. Removal efficiency of arsenic and turbidity for ferric chloride (8 mg/L) of up to 59.5% at pH 8 and 90.6% at pH 8 respectively were observed. Optimum arsenic and turbidity removal for alum dosages were achieved with a 25 mg/L and 16 mg/L respectively. Optimum arsenic and turbidity removal for ferric chloride dosages were achieved with a 20 mg/Land 8 mg/L respectively. In terms of minimizing the arsenic and turbidity levels, the optimum pH ranges were 6.5 and 8for alum and ferric chloride respectively. When a dosage of 2 mg/L of potassium permanganate and 8 mg/L of ferric chloride were employed, potassium permanganate can improve arsenic removal, but not turbidity removal.

The blue-green algae which caused odor problem in the tap water are difficult to precipitate in sedimentation basin and clogged the filter void rapidly. The studies of this paper were not only oxidation, coagulation and sedimentation processes for effectively removing blue-green algae but yellow clay and polyamine for verification as coagulants aids. The results of this research are summarized as follows: Higher ozone dose(C) and longer contact time(T) were needed for a high degree of removing blue-green algae efficiency. the removal rate of blue-green algae was proportional to the C×T value. The removal percent of chlorophyll-a by sedimentation and filter without pre-ozonation was about 75% but 1 mg/L pre-ozonation could increase the removal percent of chlorophyll-a to 99% and more pre-ozonation could remove completely. Though the removal efficiency of turbidity could increased by high dose of chlorination, the dissolved organic carbon was increased. More chlorine dose from 4 to 10 mg/L dissolved organic carbon was decreased. Using yellow clay as coagulant aids increased density of floc so the settling velocity of floc become rising but polyamine could not increase settling velocity of floc though it could formated large floc.

The bacterial community structure in biological activated carbon (BAC) process in drinking water treatment plant was investigated by Fluorescent in situ Hybridization (FISH) with rRNA-targeted oligonucleotide probe. Samples were collected at different three points in BAC process every month for one year. They were hybridized with a probe specific for the alpha, beta, gamma subclass of the class Proteobacteria, Cytophaga- Flavobacteria group and Gram-positive high G+C content (HGC) group. Total numbers of bacteria in BAC process counted by 4',6-diamidino-2-phenylindole (DAPI) staining were 5.4×1010 (top), 4.0×1010 (middle) and 2.8×1010 cells/ml (bottom). The number of the culturable bacteria was from 1.0×107 to 3.6×107 cells/ml and the culturability was about 0.05%. The faction of bacteria detectable by FISH with the probe EUB338 was about 83% of DAPI counts. Gamma and alpha subclass of the class Proteobacteria were predominant in BAC process and their ratios were over 20% respectively. In top and middle, alpha, beta and gamma subclass of the class Proteobacteria competed with each other and their percentages was changed according to the season. In bottom, gamma subclass of the class Proteobacteria was predominant all through the year. It could be successfully observed the seasonal distribution of bacterial community in biological activated carbon process using FISH.