• Proceedings of the Korea Water Resources Association Conference
• /
• 2008.05a
• /
• pp.827-831
• /
• 2008

In this study, the effects of reclaimed wastewater irrigation on the concentration of heavy metals such as lead, zinc, cadmium, and copper in soil and vegetables were investigated by monitoring an experimental area irrigated with reclaimed wastewater. Three treatments and three replications on $10{\times}2$-m plots were installed and heavy metal concentrations in soil and vegetables were monitored from 2005 to 2007. The treatments applied in this study were groundwater irrigation (control treatment), wastewater irrigation, and irrigation with filtered reclaimed wastewater treated with ultraviolet light. The monitored results showed that the concentrations of Cu, Cd, and Pb in soil during the experimental period were lower than initial soil levels before irrigation, whereas Zn increased in all treatment plots. However, the ranges of Zn, Cu, Cd and Pb in soil were below the soil pollution standards in the Republic of Korea. Heavy metal concentrations in vegetables showed insignificant variations for all treatments.

• Proceedings of the Korean Society of Agricultural Engineers Conference
• /
• 2003.10a
• /
• pp.267-270
• /
• 2003

This paper presents a recent finding from the progressed research efforts on the application for wastewater reclamation and reuse for agricultural uses. Reclaimed effluents from the Suwon municipal sewer treatment plant has been used to irrigate paddy rice at experimental plots. Three levels of reclamation treatments, filtration, disinfection, and the both, and one treatment to apply heavily polluted stream flow are compared to the control which uses groundwater for irrigation. The rice growth indicated by plant height and tiller number, and the yields were compared statistically among the five treatments. The results showed that the rice yields from polluted stream were greatest, and the control showed the lowest yields. And the first year experiment indicated that the agricultural reuse is promising.

• Proceedings of the Korean Society of Agricultural Engineers Conference
• /
• 2003.10a
• /
• pp.583-586
• /
• 2003

The objective of this research was to examine the significance of change to indicator microorganisms (TC, FC, and E. coli) in the paddy field and repair of UV disinfected secondary effluent. Average concentrations of Microorganisms were maintained by more than about 1,000 MPN/100mL in paddy field after irrigation. Microorganism repair was evaluated in relation to UV dose in photoreactivating light and dark. In addition, a significant inverse relationship was found between UV dose and repair of indicator microorganisms when the research of wastewater was conducted in the condition of low and high UV dose.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
• /
• 2001.02a
• /
• pp.193-196
• /
• 2001

This paper deals with the fabrication and characteristic experiment of a high-Tc superconducting(HTSC) power supply using by Bl-2223 tape. The purpose of this research is to apply real HTSC load. This system consists of two heaters, an electromagnet, a Bi-2223 solenoid and a Bi-2223 pancake load. In the experiment. 17sec and 8.5sec were used for pumping period. Mechanism of the superconducting switch is used for heater-trigger. In experiment, the pumping-current has reached about 1.2A.

• Proceedings of the KIEE Conference
• /
• 2004.04a
• /
• pp.284-286
• /
• 2004

기존노선을 이용한 고속화 신기술 개발사업 과제를 수행하여 중장거리 및 도시간의 교통해소를 위해 중고속 철도차량을 개발하여 최고속도 180km/h의 속도로 운행할수 있는 차량의 주요 전기시스템인 주변압기, 주변환장치, 견인전동기, 보조전원장치의 설계 및 사양을 정립하여 TTX차량을 제작하는 연구를 수행하였다.

• Journal of the Korean Society of Industry Convergence
• /
• v.23 no.1
• /
• pp.17-24
• /
• 2020

This study analyzes economic feasibility by looking at the case of wastewater reclamation and reuse system of Osan, the only place currently operated in Korea, exploiting wastewater uniquely reused as industrial water. Furthermore, this paper examines the problem in wastewater recycling and present the method to expand the potential of using reclaimed water. Method to activate the reuse of wastewater as industrial water. First, it is required to provide self-governing body and demander with diverse information on this project so that they correctly recognize the reuse of wastewater as industrial water. Second, law should be amended so that the water quality requirement of reused water can be given in the national level to supply industrial water depending on right standard. Third, financial support should be expanded in diverse parts so that more private investment advantageous to investor can be made, for instance, BTL, BTO.

• Proceedings of the Korean Society of Agricultural Engineers Conference
• /
• 2005.10a
• /
• pp.643-648
• /
• 2005

The objective of this paper is to analyze the environmental effects by the fertilizer change with wastewater reuse for agriculture. For this research, Lysimeter tests are being implemented to cultivate rice with different levels of fertilizer applications with wastewater irrigation., and to analyze the nutrient loading by wastwater reuse in paddy fields was examined the CREAMS-PADDY model. CREAMS-PADDY model is modified from CREAMS model for considering the hydrologic cycles in paddy field. As a result, in the lysimeter treated by irrigation with wastewater and chemical fertilizer with half of the conventional amount showed generally similar tendency to the control plot. This may require the modifications of standard cultural practices for rice in terms of fertilizer and pesticide applications. However, high concentration of sodium in wastewater might cause damage to physico-chemical properties of paddy soil. And the wastewater reuse effects on nutrient loads were quantitatively analyzed and this results provide the reasonable management for agricultural reuse.

• Proceedings of the KIEE Conference
• /
• 2001.04a
• /
• pp.12-14
• /
• 2001

This paper deals with the fabrication and characteristic experiment of a high-Tc superconducting (HTSC) power supply using by Hi-2223 tape. The purpose of this research is to apply real HTSC load. This system consists of two heaters, an electromagnet, a Bi-2223 solenoid and a Bi-2223 pancake load. In the experiment, 17sec and 8.5sec were used for pumping period. Mechanism of the superconducting switch is used for heater-trigger. In experiment, the pumping-current has reached about 1.2A.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.53 no.4
• /
• pp.59-65
• /
• 2011

The purpose of this study was to analyze the water quality change when wastewater applied to study paddy fields. CREAMS-PADDY (Chemical, Runoff and Erosion from Agricultural Management System) model was used to estimate the field-scale water quality. Simulated results were compared with observed data monitored from Byeongjeom study paddy fields which is located near the Suwon sewage treatment plant in Gyeonggi-do. Significance analysis was performed for the three different irrigation water quality level and five fertilizer reduction scenarios using LSD (Least Significant Difference) and DMRT (Duncan's Multiple Range Test). Total nitrogen was found to be significant for both irrigation water quality level and fertilizer reduction while total phosphorus was not. Annual drainage load for total nitrogen was reduced by 66~92 % compared to irrigation load when treated wastewater irrigated to study paddy fields from 2002 to 2007. Total phosphorus was reduced by 70~86 %.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.4 no.1
• /
• pp.41-48
• /
• 1998

There are several serious problems in treating shipboard wastewater due to special environmental conditions of ship, such as confined space, rolling and pitching, change of temperature and so on. It was suggested that Sequence Batch Reator (SBR) process might be suitable for overcoming above problems in terms of small size, high capacity of treating wastewater and full automation. In this study the SBR process was used for the secondary treatment of shipboard wastewater. The average removal efficiency of DOC, nitrogen, phosphorus and surfactants(MBAS) were studied and the effects of various C/N ration on the efficiency of treatment were investgated. From the experimental results it was convinced that the SBR process would be able to be used as a suitable process for removing organic matters and nitrogen in reuse system of shipboard wastewater.