Several endocrine disrupting chemicals(EDCs) were monitored to evaluate the estrogenic activities and the concentrations by yeast two-hybrid assay and enzyme-linked immunosorbent assay(ELISA) in sewage treatment plant(STP) which consist of industrial and domestic line. In the influent of domestic line, estrone, 17-estradiol, 17-ethinylestradiol and alkylphenolethoxylate(APE) were detected up to 167.1, 39.7, 7.3 and 145.4 ng/L, respectively. The average removal efficiency of 17-estradiol after the activated sludge process was 77.5% and further removed to 80.8% after the sand filtration-ozonation step. These results suggests that the activated sludge process has limited potential to remove the estrogenic activity effectively. The contributions of the estrogenic chemicals to the estrogenic activities were 70.7, 23.3, 3.7 and 2.3% for estrone, 17-estradiol 17-ethinylestradiol and APE, respectively, in the domestic line effluents. Therefore, 17-estradiol and estrone contributed most of the estrogenic activity in the domestic line effluents.

This study investigated the dechlorination mechanisms of TCE by Fe(II) associated with cement. Batch slurry experiments were peformed to investigate the behaviors of selected ions; Fe(II), Fe(III), , in cement/Fe(II) system. The kinetic experiments of TCE in cement/Fe(II) systems showed that injected Fe(II) was mostly sorbed on cement within 0.5 day and 90% of injected 200 mM sulfate was sorbed on cement within 0.5 day when = 0.25 mM and = 200 mM. The kinetic experiments of TCE in hematite/CaO/Fe((II) systems were conducted for simulation of cement/Fe(II) system. Calcium oxide that is one of the major components in cement hydration reactions or has a reactivity in limited conditions. Hematite assumed the ferric iron oxide component of cement. The reactivities observed in hematite/CaO/Fe(II) system were comparable to those reported for cement/Fe(II) systems containing similar molar amounts of Fe(II). The behavior of Fe(II) and sorbed on solid phase at an early stage of reaction in hematite/CaO/Fe(II) system was similar to that of cement/Fe(II) system. Ferric ion was released from hematite at an early period of reaction at low pH. The experimental evidence of kinetic test using hematite/CaO/Fe(II) system implies that the reactive reductant is a mixed-valent Fe(II)-Fe(III) mineral, which may be similar to green rust. Fe(II) sorbed on cement can be converted to new mineral phase having a reactivity such as Fe(II)-Fe(III) (hydr)oxides in cement/Fe(II) systems.

To investigate the effects of alkalinity on the nitrification capability of the nonwoven fabric filter bioreactor(NFBR), an experiment was performed for 641 days at a hydraulic retention time of approximately 11 hours by changing the influent concentration of from 54 mg/L to 1,400 mg/L and alkalinity from 43 mg/L to 10,480 mg/L. The MLSS concentration reduced from an initial value of 2,650 mg/L down to 830 mg/L, then increased up to 8,340 mg/L. Though the volumetric loading rate varied in a range of kg , the F/M ratio showed a narrow range of kg MLSS-day. The average nitrification efficiency at each experimental stage resulted in the range of , and the maximum nitrification rate was 2.970 kg or 0.489 g N/g MLVSS-day. The nitrifiers' fraction of the MLVSS increased up to 100% from an initial value of 7.1% and the biofilm formed on the nonwoven fabric filter showed a very low nitrifiers' fraction of mere 2.2%. The growth yield of the MLSS and the alkalinity consumption rate were computed to be 0.117 g VSS/g N removed and 7.08 g alkalinity/g produced, respectively. Results of the research suggest that NFBR could be an adequate process for nitrification of wastewaters with high ammonia concentrations.

A total of 48 samples of street dust were collected in Daegu area during April and May 2006, were sieved below 100 , and analysed by ICP for the analysis of 14 elements after an acid extraction. Results obtained from the source assessment of trace elements using enrichment factor showed that Ca, Fe, K, Mg, Mn, Na and V were influenced by natural sources such as soil and dust, while Cd, Cr, Cu, Ni, Pb and Zn were influenced by urban anthropogenic sources such as fuel combustion and waste incineration. The measured values were remarkably higher in components from natural sources than in components from urban anthropogenic sources. The concentrations of trace elements in Daegu area were generally higher than in other foreign cities. Samples originated from industrial and commercial areas had higher concentrations of trace elements and pollution indices of heavy metals than those from residential and green areas. The correlation analysis among trace elements indicated that the correlations among components from urban anthropogenic sources were much significant, while those among components from natural sources were less correlated. In addition there were significant correlations between traffic density and components from urban anthropogenic sources.

Fly ash and blast furnace slag are an industrial by-product that can be alkali-activated to yield adhesive and cementitious materials, whose production is less energy-intensive and emits less than ordinary Portland cement manufacture. A laboratory investigation was carried out to evaluate the effect of alkali-activating conditions on compressive strength of fly ash/slag cement and the acid corrosion resistance of this cement. Two alkali activator solution, NaOH and waterglass + NaOH solutions, were used. Waterglass concentration was the factor that gave the highest compressive strength in all tests. The next significant factor was the NaOH concentration, followed by curing temperature. Acid corrosion resistance of FC(fly ash cement) and FSC(fly ash/slag cement), such as sulfuric and hydrochloric acid(HCl), was for better than Portland cement(PC).

Investigation of alkali activation of fly ash and blast furnace slag was carried out using waterglass and sodium hydroxide. XRD, FTIR, and NMR, TGA and SEM were used to observed the reaction products and microstructure of the fly ash/slag cement (FSC) pastes. The reaction products were amorphous or low-ordered calcium silicate hydrate and aluminosilicate gel produced from alkali activation of blast furnace slag and fly ash, respectively. On the basis of this investigation, waterglass solution with a modulus(Ms) of 1.0 and 1.2 is recommended for alkali activation of fly ash and blast furnace slag. Morphology of FSC pastes alkali-activated with Ms of 1.0 and 1.2 shows a more solid and continuous matrix due to restructuring of gel-like reaction products from alkali-activated fly ash and blast furnace slag together with another hydrolysis product(i.e., silica gel) from water glass.

Earthworm casting was the natural fertilizer that contained high concentrations of nutrients such as nitrogen, phosphate and potassium and of over CFU/ml of microorganisms. Greater than 80% of feed was excreted through the fermentation by the intestinal enzyme, after worm had eaten feeds such as fallen leaves and rotten roots under the ground. Also, the soil structure of casting was known to be very efficient in the aspects of the porosity, the water permeability, and deodorizing activities. In this research, the biofilter packed with a biomedia made of casting and waste polyurethane foam, a binder, which helped to improve the durability and perpetuity of casting, was investigated to degrade malodorous hydrogen sulfide gas. The biomedia had no need of extra supply of nutrients and of microbial inoculations. On the beginning of the operations, it showed 100% removal of hydrogen sulfide gas without lag phase. At SV of 50 , hydrogen sulfide gas from the outlet of the biofilter was not detected, when inlet concentration increased to 450 ppmv. After that, removal efficiency decreased as increasing inlet hydrogen sulfide concentration. Hydrogen sulfide removal was maintained at almost 93% until inlet concentration was increased up to 950 ppmv, at which the elimination capacity of was 61.2 g . Maximum elimination capacity guaranteing 90% removal was 61.2, 65.9, 84.7, 89.4 g at SV ranging from 50 to 300 , but was 59.3 g at SV of 400 . The results calculated from Michaelis-Menten equation revealed that increased from 66.04, 88.96, 117.35, 224.15, to 227.54 g with increasing space velocity in the range of 50 to 400 . However, saturation constant decreased from 79.97 ppmv to 64.95 and 65.37 ppmv, and then increased to 127.72 and 157.43 ppmv.

Unpleasant tastes and odors in drinking water cause same problems for water utilities across Korea. Even though tastes and odors do not create health problems, they are main concerns for consumers who determine the safety of their drinking water. In this study, two different odor producing compounds(geosmin 2-MIB) in the Nakdong river water and rapid sand filtered rater were treated by advanced oxidation of process. The experimental results showed that the removal efficiency of geosmin with the use of 5 mg/L of and was higher than efficiency with the use of alone for both the raw water and the sand filtered water. And in general, the removal efficiency of geosmin was higher than 2-MIB in the sand filtered water. Under the range of concentration mg/L, the removal rate constants(k) of geosmin for the raw and sand filtered waters, and the one of 2-MIB in the sand filtered water were increased rapidly as doses of , and , increased. The removal rate constants(k) do not increase any more when ratio increases above the optimum ratio. The optimum ratio of , dose was for both geosmin and 2-MIB. The removal rate constant(k) becomes lower when OH radical consuming materials are present in raw water. The half-life of geosmin decreased rapidly as the and doses increase in the sand filtered water. The half life decreased about 8.5 times with the use of 2 mg/L of and 10 mg/L of than with the use of 2 mg/L of alone for the sand filtered water.

In this study, adhesion and transport of bacteria in positively-charged media was investigated with batch and column experiments. Bacterial species used in this study was Escherichia coli ATCC 11105(length: 2.2 , diameter: 0.6 ) and media used were quartz sand(particle size distribution: 0.5-2.0 mm, mean diameter: 1.0 mm) and iron-coated sand. Batch results indicate that bacterial adhesion increased as the content of iron-coated media increased. At iron-coated media 0%(quartz sand 100%), around 46% of bacteria was adhered to media while at iron-coated media 100%(quartz sand 0%) about 97% was attached. Column results also show that bacterial adhesion was enhanced with an increase of iron-coated media content. As the iron-coated media content increased from 0 to 100%, bacterial adhesion increased from 8 to 94%. The experimental results demonstrate that positively-charged media could influence transport of bacteria in porous media.

Temperature dependence of kinetic constants in the anaerobic acidogenesis was investigated using anaerobic chemostat-type reactor. Glucose was used as a substrate in this experiment. Temperature ranging from 15 to were studied. The saturation constant and growth yield(Y) decreased with increasing temperature, while the maximum specific substrate utilization rate increased. A temperature correction factor values of the substrate utilization rate and bacteria growth rate were the range from 1.3 to 2.2 and 1.5 to 2.2, respectively. The growth yield(Y) for the acidogenesis process was less sensitive to temperature changes than the maximum specific substrate utilization rate. The simulation model of the relationship between the substrate and sludge retention time(SRT) at the temperature range of 20 to is obtained as the following ; .

This study was performed to compare and to examine the degradation efficiencies and degradation mechanism of pentachlorophenol(PCP) by UV, , , , and processes. The pseudo-first order rate constant was compared in each process. The addition of increased the rate constant by 13 times compared to the reaction with UV alone. The reaction rate in reaction with PCP increased 4 times and 7.25 times by adding 180 mM and 16 mM , respectively. Compared to that with , the rate constant of the reaction with UV alone reaction increased 3.1 times. These results indicates the enhancement of reaction rate is closely related to the generation of OH radical. The degree of the iron sludge production observed in reaction was significantly reduced by irradiating UV in this process.