• Journal of Korean Society on Water Environment
• /
• v.20 no.2
• /
• pp.132-144
• /
• 2004

The purpose of this study was to evaluate alternatives for stable operation of WWTP(Wastewater Treatment Plant) with a higher rate of inflows and a higher concentration of pollutants during wet weather to minimize the pollution loads being discharged into receiving waters. 3Q(Q: dry weather flow) of a base flow is normally intercepted and flows into WWTP as it was current practice. It is revealed by simulation that the bypassing alternative of 1Q through secondary treatment and 2Q into the stream after primary treatment was as good as it is expected. The bypass pollution loads were in the range of 23.9 ~ 38.5 % of the total loads flowing into the WWTP indicating that the bypassed flows need an extra treatment such as stormwater detention reservoir, high-rate coagulation with sedimentation, and step-feed. The high-rate coagulation with sedimentation was the most effective with respect to removal of the pollution loads.

• Journal of Korean Society on Water Environment
• /
• v.28 no.1
• /
• pp.109-114
• /
• 2012

In this study, both sedimentation and thickening experiments were conducted for residuals produced from an advanced water treatment plant for more accurate and practical design of residual treatment train. In order to design a backwashed residual sedimentation basin (SRSB) in the filter backwash water recycle system, two kinds of backwash waters, one from sand filter (SFBW) and the other from GAC adsorption bed (GACBW), were separately collected and their surface loading rate measured. In addition, in order to design a gravity thickener, batch thickening tests were conducted for concentrated residuals taken from sedimentation basin and their limiting solid flux ($SF_{L}$) measured. From the experimental results and consideration of the seasonal characteristics of the residual, surface loading rate of $70m^{3}/m^{2}{\cdot}d$ was proposed as a design parameter for SRSB and solid loading rate of 20 kg $TS/m^{2}{\cdot}d$ was proposed as a design parameter for gravity thickeners. Finally, the material mass-balance was made for the design of each unit process in the residual treatment train.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2011.10a
• /
• pp.36.2-36.2
• /
• 2011

Titanium and its alloys have been widely used for orthopedic implants because of their good biocompatibility. We have previously shown that the crystalline titania layers formed on the surface of titanium metal via anodic oxidation can induce apatite formation in simulated body fluid, whereas amorphous titania layers do not possess apatite-forming ability. In this study, hot water and heat treatments were applied to transform the titania layers from an amorphous structure into a crystalline structure after titanium metal had been anodized in acetic acid solution. The apatite-forming ability of titania layers subjected to the above treatments in simulated body fluid was investigated. The XRD and SEM results indicated hot water and/or heat treatment could greatly transform the crystal structure of titania layers from an amorphous structure into anatase, or a mixture of anatase and rutile.The abundance of Ti-OH groups formed by hot water treatment could contribute to apatite formation on the surface of titanium metals, and subsequent heat treatment would enhance the bond strength between the apatite layers and the titanium substrates. Thus, bioactive titanium metals could be prepared via anodic oxidation and subsequent hot water and heat treatment that would be suitable for applications under load-bearing conditions.

• The Journal of Korean Medicine
• /
• v.21 no.4
• /
• pp.84-92
• /
• 2000

Objectives : The water extract of Sebsaeng-eum(SheShengYin) has been used for treatment of ischemic brain damage in oriental medicine, However, little is known about the mechanism by which the water extract of Sebsaeng-eum(SheShengYin) rescues brain cells from ischemic damages. Methods : To elucidate the protective mechanism on ischemic induced cytotoxicity, We investigated the regulation of LPS and PMA induced iNOS expression in $C_{6}$ glial cells. Results : LPS and PMA treatment for 48 h in $C_{6}$ glial cells markedly induced NO, but treatment of the cells with the water extract of Sebsaeng-eum(SheShengYin) decreased nitrite formation. In addition, LPS and PMA treatment for 48 h induced severe cell death in $C_{6}$ glial cells. However treatment of the cells with the water extract of Sebsaeng-eum(SheSheng Yin) did not induce significant changes compared to the control. LPS and PMA induced iNOS activation in $C_{6}$ glial cells caused chromosomal condensation and fragmentation of nuclei. Conclusions : Taken together, We suggest that the protective effects of the water extract of Sebsaeng-eum(SheShengYin) against ischemic brain damages may be mediated by regulation of iNOS during ischemic condition.

• Journal of Korean Society on Water Environment
• /
• v.29 no.1
• /
• pp.127-137
• /
• 2013

Reuse of wastewater will intensify in the coming decades due to water shortage, the change of climatic conditions, the need for industrial and agricultural use and the necessity of improving health and environmental conditions for the growing population. This paper considers (a) the status and trends of wastewater reuse and reclamation in the world, (b) case studies of wastewater reuse projects, (c) analysis of technology level, (d) forecast of global market, and (e) the future views and directions in development of wastewater reuse technologies. Based on the available documented literature, this paper provides a review assessment of the current status of the wastewater treatment processes including potential applications for reuse. Key challenges for both wastewater treatment and reuse are also discussed in the paper and include recommendations, e.g. cost, effluent water quality, energy use and technical solutions, for future developments.

• Journal of Korean Society of Water and Wastewater
• /
• v.31 no.4
• /
• pp.289-296
• /
• 2017

Pulp and paper industry produces large volumes of wastewater and residual sludge waste, resulting in many issues in relation to wastewater treatment and sludge disposal. Contaminants in pulp and paper wastewater include effluent solids, sediments, chemical oxygen demand (COD), and biological oxygen demand (BOD), which should be treated by wastewater treatment processes such as coagulation and biological treatment. However, few works have been attempted to predict the treatment efficiency of pulp and paper wastewater. Accordingly, this study presented empirical models based on experimental data in laboratory-scale coagulation tests and compared them with statistical models such as artificial neural network (ANN). Results showed that the water quality parameters such as turbidity, suspended solids, COD, and UVA can be predicted using either linear or expoential regression models. Nevertheless, the accuracies for turbidity and UVA predictions were relatively lower than those for SS and COD. On the other hand, ANN showed higher accuracies than the emprical models for all water parameters. However, it seems that two kinds of models should be used together to provide more accurate information on the treatment efficiency of pulp and paper wastewater.

• Journal of Environmental Science International
• /
• v.7 no.2
• /
• pp.217-222
• /
• 1998

Organics matters including algae are the major contaminants of Nak-dong river and it's concentration Is more Increasing now. The use of coagulants has been Incresed for the effective treatment of drinking water, and aluminum coagulants have been the most widely used in raw water treatment. However, when inorganic metal coagulant is excessively used for long period, it would result in secondary problems, such as increasing sludge production, enhancing the cost of water treatment process, and increasing concentration of residual metal, especially aluminum. Therefore, recently. in order to reduce the use of metal coagulant and enhance the coagulation effectiveness, several alternative coagulants, such as polymeric Inorganic coagulants and organic polymers, have been used In water treatment plants. The objectives of thins research were (11 to determine optimum dosage concentration and compare the coajuiation efnciency at various pH ranees with alum alone, alum+cationic polymer, and alum+anlonlc polymer, (21 to evaluate the amount of alum reduced by using organic polymer, (31 to maximize removal officiency of organic matter and minimize the concentration of residual aluminum.

• Journal of Institute of Convergence Technology
• /
• v.1 no.2
• /
• pp.37-42
• /
• 2011

The purpose of this research is to improve nitrogen removal efficiency in winter season through rise of water temperature of extraneous water by using solar energy which is estimated to have great potential among new regeneration energy and while operating Plug-Flow Reactor to improve nitrogen removal efficiency by selecting A/O process among sewage waste water treatment processes as the necessity of solving the problem of nitrogen removal efficiency according to reduced water temperature in winter season and strengthening of water quality criteria regarding discharged sewage waste water suggested in the research background. Summarizing the research result, supply of solar energy source improves the function outstandingly when removing nitrogen, (nitrogen removal rate before operating solar energy 55.4% ${\rightarrow}$ nitrogen removal rate after operating solar energy 84.1%).

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.54 no.3
• /
• pp.155-159
• /
• 2005

This paper presents the water treatment system with high performance electromagnetic field for a good quality of water. The electromagnetic field water treater consists of a solion, a solion body, and a high voltage converter. The high voltage converter is controlled by PWM current controller. The high voltage converter of 13W is designed for an isolation operation amp, an isolation current detector, and an over current protector. Using the high voltage PWM converter, the system with the proposed electromagnetic field water treater can be controlled easily. Simulation and experimental results show the effectiveness of the system strategy proposed for the scale rejection.

• Proceedings of the Korean Society of Agricultural Engineers Conference
• /
• 2001.10a
• /
• pp.470-474
• /
• 2001

A pilot study was performed at the experimental field of Konkuk University in Seoul, to examine the waste water treatment using constructed wetland and pond system. The effluent of the wetland system in winter often exceeded effluent water quality standards for sewage treatment plant, therefore, pond system could be applied to additional system. As a result, removal rate of $BOD_{5}$, SS was 84.4%, 81.5% and effluent concentration was 4.6mg/L and 5.0mg/L respectively, when surface water of pond system was discharged in March. So we concluded that pond system stored wetland effluent in winter and discharged surface water of pond system in March, so met water quality standard.