• Journal of Environmental Health Sciences
• /
• v.24 no.3
• /
• pp.54-62
• /
• 1998

20 bacterial strains capable of growing on phenol minimal medium were isolated from soil and wastewater by the enrichment culture technique, and among them, one isolate which was the best in the cell growth was selected and identified as Bacillus sp. SH3 by its characteristics. Strain SH3 could grow with phenol as the sole carbon source up to 15 mM, but did not grow in minimal medium containing above 20 mM of phenol. The optimal conditions of temperature and initial pH for growth and phenol degradation were 30$^{\circ}$C and 7.5, respectively. This strain could grow on various aromatic compounds such as catechol, protocatechuic acid, gentisic acid, o-, m-, p-cresol, benzoic acid, p-hydroxybenzoic acid, anthranilic acid, phenyl acetate and pentachlorophenol, and the growth-limiting log P value of strain SH3 on organic solvents was 3.1. In batch culture, strain SH3 degraded 97% of 10 mM phenol in 48 hours. In continuous culture under the conditions of 20 mM of influent phenol concentration and 0.050 hr$^{-1}$ of dilution rate, the treatment rate of phenol was 94%.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2002.04a
• /
• pp.254-257
• /
• 2002

The purposes of this research are to identify the source and to analyze the pathway of nitrate contamination in "cultural village", Jeungpyeong. In order to examine recharge processes and flow pattern that closely related to the influent of nitrate contaminant, the flow field was simulated and the oxygen and hydrogen stable isotopes were analyzed. The nitrogen isotope was used to delineate contaminant sources. The shallow groundwater was mainly composed of precipitation, but leakage of domestic water and sewage contributed to the recharge. Nitrate contaminants were possibly from the leakage of sewage and animal waste. The nitrate concentration decreased due to dilution by low concentration water.ion water.

• Journal of Korean Society on Water Environment
• /
• v.23 no.3
• /
• pp.367-370
• /
• 2007

Numerous sets of simulation were conducted in order to find out the optimum operational conditions of the existing BNR process using GPS-X program. The model of ASM3 and modified Bio-P module were applied for simulations. From the result of this study, effluent quality was closely related with the step feeding rate and influent C/N ratio. The effluent TN concentration seemed to be significantly affected by step feeding rate at the low C/N condition. But at the high C/N condition, the effluent concentration of TP rather than that of TN was affected by the control of step feeding rate.

• Journal of Korean Society on Water Environment
• /
• v.29 no.3
• /
• pp.337-342
• /
• 2013

The particle counter compared with the turbidimeter provides good precision and sensitivity and can get the characteristics of particulates effectively. The purpose of this study is to provide the application of particle counter in sand and activated carbon filters. The particle count by size could be more easily sense when the water quality is changed by the influent of high turbidity or algae. We could decide the optimal backwashing cycles and detect the efficiencies of filters by monitoring the total particle count of effluent in sand and activated carbon filters.

• Journal of Korean Society of Water and Wastewater
• /
• v.12 no.2
• /
• pp.67-75
• /
• 1998

The purpose of this study is to develop a system for treating industrial wastewater with high carbonaceous and nitrogenous materials. To investigate the potential of using this system, a number of experiments are conducted for about 7 months with the varieties of COD and $NH_3-N$ concentrations, and hydraulic retention time. In the system, 1,500mg/L of COD is remover over 95% in a retention time as low as 9 hours, and the $NH_3-N$ removal efficience is nearly 100% with 90mg/L of $NH_3-N$ in the influent. These results illustrate that the system can effectively be used to treat industrial wastewater containing high concentration of COD and $NH_3-N$.

• Journal of Korean Society of Water and Wastewater
• /
• v.10 no.3
• /
• pp.55-63
• /
• 1996

Nitrification reaction consists of two reactions: nitritification which oxidizes ammonia nitrogen to nitrite nitrogen and nitratification which oxidizes nitrite nitrogen to nitrate nitrogen. Each reaction is carried out by Nitrosomonas and Nitrobacter, respectively. The effective maximum growth rates for both bacteria have to be determined to design aeration tank whenever the aeration tanks have to nitrify ammonia nitrogen in influent. And these values are very important to use mathematical models such as IAWPRC model to simulate nitrification in activated sludge. There are several methods to determine these valves, however, the Fed-Batch experiments can determine these values within 72 hours. In this study, the mathematical equations and experimental procedures for Fed-Batch test are presented. Also, the experimental data and reported values are compared. The estimated mean values of maximum specific growth rates for Nitrosomonas and Nitrobacter are $0.5010day^{-1}$ and $0.6704day^{-1}$, respectively.

• Journal of Environmental Science International
• /
• v.5 no.4
• /
• pp.513-524
• /
• 1996

Laboratory investigation was conducted to evaluat the mixing effects on organic removal efficiency to treat low-strength synthetic wastewater using modified anaerobic - filter reactor combining anaerobic filter and upflow anaerobic sludge blanket. Using the modified process the low-strength wastewater like municipal sewage could be treated with 85% T-COD removal efficiency at hydraulic retention time of 6 hours. At the constant organic loading of 0.5 kg COD/m 3-day, the organic removal efficiency and effluent COD concentration are increased as influent COD concentration increased from 125 mg/l to 500 mg/l. Mixing effects on organic removal efficiency are evident and optimum mixing speed is found as 50RPM. Placing the granular sludge and media on which slime layer was pre-formed into the reactor seemed to be very effective In achieving short start-up period. Therefore, the steady state was achived after 4 weeks and 1 week based on T-COD and S-COD, respectively.

• Journal of Environmental Health Sciences
• /
• v.27 no.3
• /
• pp.11-20
• /
• 2001

An anaerobic sludge-aerobic fixed-bed biofilm(packed with ceramic support carrier of 1 inch size) reactor system was built up to treat textile wastewater. The efficiency of reactor system was examined by determining the effects of textile wastewater ratio(from 25% to 100% at HRT 24 h). The influent range of SCOD concentration and color were 1,036~1,357 mg/L, and 1,487~1,853 degree, respectively. When textile wastewater ratio was 100% and hydraulic retention time was 24 hours, SCOD removal efficiency by the anaerobic stage were 39.2% 100% and hydraulic retention time was 24 hours, SCOD removal efficiency by the anaerobic stage were 39.2% and the removal efficiency of the whole system were 75.8%. Color removal efficiency by the anaerobic stage were 45.4%(soluble color), and the removal efficiency of the whole system were 70.2%. In the A/A reactor system, the aerobic stage played an important role in removing both color and COD as well as anaerobic stage.

• Journal of Environmental Science International
• /
• v.14 no.12
• /
• pp.1155-1161
• /
• 2005

Anoxic-oxic process were analyzed numerically for the each unit and final TN effluent by Water Quality Management(WQM) model and the results were compared data from these sewage or wastewater treatment plants. No bugs and logic error were occurred during simulation work. All of the simulation results tried to two times were obtained and both results were almost same thus this model has good reappearance. A few of simulation results were deviated with measured data because lack of influent water qualities are reported however simulation results have wholly good relationship with measured data. Also each unit of simulation result was kept good relationship with that of measured data therefore this WQM model has good reliance. Finally, WQM model predicts final TN effluent within ${\pm}4.1\;mg/{\ell}$

• Journal of Bio-Environment Control
• /
• v.3 no.2
• /
• pp.136-144
• /
• 1994

A long- time aeration method was developed for purification of animal wastewater. Under repeated aereations of 4 hours on and 4 hours off, the higher removal rates were obtained which were in average of 99%, 96%, 92% and 50% for BOD, SS, total nitrogen and phosporous, respectively. In detail, the measured BOD concentrations of the influent and effluent were 2,700ppm and 40ppm while the SS concentrations in the primary chamber and of the effluent were about 3,000 and 110 ppm, respectively. Zeolite and activated carbon, applied for removing the nitrogen and phosphorous, showed a good absorption, especially zeolite for NH$_4$-N and activated carbon for NO$_3$-N and PO$_4$-P. The treatment cost per head by this method amounts to 1,923 won and it comes to 1.6% in the whole production cost. Therefore, this method is economically available with the half cost of the conventional activated sludge process.