• Journal of Industrial Technology
• /
• v.27 no.B
• /
• pp.3-7
• /
• 2007

Ultraviolet light(UV-C, wavelength: 200~280nm) is employed profitably for sterilizing drinking water. For most water serving apparatus such as a water purifier, a water cooler and heater, a coffee vending machine and etc., pre-sterilized water may be contaminated secondarily with bacillary inhabitation in a container before serving. In consideration of this problem, a household water tap which is equipped with a sterilization/Purification device in combination with non-contact UV-lamp, was designed to sterilize and purify water at the last outlet just before serving. Hopefully this simple but creative item may be commercialized for household and public use.

• Journal of Korean Society on Water Environment
• /
• v.23 no.5
• /
• pp.766-775
• /
• 2007

The use of toxic chemicals was extended as the industry in Korea has grown dramatically during the last three decades. However, list of toxic substances and limit concentrations in the water environment are not consistent within management of ambient water, drinking water and industrial effluent. This article suggests the systematic framework to classify toxic substances in the water environment and deriving their effluent limits. The most important factor for decision-making to classify toxic substances is whether their concentrations in the water environment are higher than the reference concentrations, estimated by considering human health risk and ecological risk. Using a risk-based reference concentration, the ambient water quality criterion, it is possible to derive the regulatory limit concentrations of toxic substances in drinking water and in industrial effluent. The goal concentrations in the effluent, which guarantee the human and ecological safety, should be determined with scientific investigation, balancing environmental benefit and economical effect, considering availability of treatment technology and identifying characteristics of wastewater from different industries.

• Journal of the Korean Society of School Health
• /
• v.33 no.2
• /
• pp.125-138
• /
• 2020

Purpose: The study investigated the effect of adolescent health behavior on the prevalence of current allergic diseases. Methods: The subjects were 57,303 middle and high school youth. Data were analyzed using Rao-Scott χ² test and complex sample logistic regression analysis. Results: While controlling the affect of the general characteristics of the subjects, health behaviors affecting the current prevalence of allergic diseases were smoking, drinking, physical activity, eating habits, drug abuse, and mental health. Smoking behaviors affecting the current prevalence of allergic diseases were lifetime smoking experience, smoking days, liquid e-cigarette lifetime smoking experience, number of liquid electronic cigarette smoking days, e-cigarette lifetime smoking experience, e-cigarette smoking days, amount of smoking, second-hand smoking and drinking behaviors were lifetime drinking, drinking days, the amount of drinking, and severe drinking. Variables such as physical activity exceeding 60 minutes days, intake of energy and sweet drinks, water intake, habitual drug use and mental health behavior such as stress perception, weekday sleep time, subjective sleep satisfaction, depression, suicidal thoughts/ plan/ attempts affect current allergic diseases (p<.001). Conclusion: The results showed that current allergic disease related health behaviors in Korean adolescents. Therefore, considering these factors, it may be helpful to facilitate a health promotion plan for prevention and management of such diseases and to promote evidence-based health practices at school.

• Journal of the Korean housing association
• /
• v.19 no.1
• /
• pp.79-88
• /
• 2008

Hot water is used by having a wash, dishes, taking tub and drinking water in residential buildings, and the use objective is to raise comfort of human body sense, washing and sterilization effect and so on. Cold & hot water supply system is understanded simpler than HVAC systems relatively, so it is true that pace of performance improvement is slower than other systems for plan and technical development. In this study, the performance evaluations are conducted under the condition of composition ratio by 1:1 for cold & hot water supply manifold system using functionally complex valves such as constant flow regulating valve and 3-way mixing valve in the area of $105.6m^2$ apartment which consist of the largest part of the whole apartment. Also, flow rate related to simultaneous use of faucets and change of hot water temperature are compared with the existing method.

• Advances in nano research
• /
• v.10 no.4
• /
• pp.397-414
• /
• 2021

The steady growth in population has led to an enhanced water demand and immense pressure on water resources. Pharmaceutical residues (PRs) are unused or non-assimilated medicines found in water supplies that originate from the human and animal consumption of antibiotics, antipyretics, analgesics etc. These have been detected recently in sewage effluents, surface water, ground water and even in drinking water. Due to their toxicity and potential hazard to the environment, humans and aquatic life, PRs are now categorized as the emerging contaminants (ECs). India figures in the top five manufacturers of medicines in the world and every third pill consumed in the world is produced in India. Present day conventional wastewater treatment methods are ineffective and don't eliminate them completely. The use of nanotechnology via advanced oxidation processes (AOP) is one of the most effective methods for the removal of these PRs. Present study is aimed at reviewing the presence of various PRs in water supplies and also to describe the process of AOP to overcome their threat. This study is also very important in view of World Health Organization report confirming more than 30 million cases of COVID-19 worldwide. This will lead to an alleviated use of antibiotics, antipyretics etc. and their subsequent occurrence in water bodies. Need of the hour is to devise a proper treatment strategy and a decision thereof by the policymakers to overcome the possible threat to the environment and health of humans and aquatic life.

• Proceedings of the Membrane Society of Korea Conference
• /
• 1998.06a
• /
• pp.81-94
• /
• 1998

Nowadays, membrane separation such as reverse osmosis (RO) and ultrafiltration (UF) play an important role in the industrial separation technology. Among desalination technologies available today, reverse osmosis is usually the most economical process for wide range of water salinity. Main applications include production of high purity water, desalination of seawater and brackish water for a drinking water supply, treatment of waste water for environmental protection, and recovery of precious materials from industrial waste water. In this paper, we will mention membrane performance and these practical use focused on reverse osmosis membranes and ultrafiltration membranes recently developed by Toray.

• Journal of Korean Society on Water Environment
• /
• v.20 no.3
• /
• pp.236-240
• /
• 2004

Autohydrogenotrophic denitrification of high nitrate concentration contaminated wastewater in a batch-scale biofilm reactor has been investigated. High nitrate concentration decreased as pH increased from 7.01 to 9.45. The high nitrate concentrations continuously decrease from $150mg.l^{-1}$ to $0mg.l^{-1}$. Nitrite concentrations increase at about two-thirds way through the denitrification process and thereafter it decreases with time. Autohydrogenotrophic denitrification of high nitrate concentration is passible to use drinking water as well as wastewater, and to deal with wastewater treatment by hetrotrophic denitrification.

• Hwankyungkyoyuk
• /
• v.22 no.4
• /
• pp.81-94
• /
• 2009

This study was intended to develop the STS module regarding conservation of water resources, called "A Project for the Conservation of Water Resources". Since each theme consisted of 2 subject activities, they had total 8 subject activities. Developed STS module was applied to 113 male students of 11th grader of D High School in Incheon. After they received 8 periods of the developed STS module, the environmental sensitivity and environmental conservation behavior and the interest of the affective domains related to science were determined. Results were as follows; Four themes of this module were 'What are the water resources?', 'What is a main cause for the water pollution?', 'A drinking water? or non-drinking water?' and 'Making UCC for the water resources'. Since each theme consisted of 2 subject activities, they were for total 8 periods. Developed STS module was found to be appropriate for the STS and they could be applied to the classroom easily. Students who were instructed according to the developed STS module showed that there was a statistically significant enhancement in the environmental sensitivity and environmental conservation behavior and in the area of interest of the affective domains related to science. Students who were instructed according to the developed STS module showed positive responses to the instructional methods by STS. Based on students' interview, they revealed that they were impressed with the hands-on activities and the process of subject activities. Instruction with STS module seemed to be more appropriate way of teaching compared to the traditional way of teaching. However, it will be necessary to develop more modules or programs which could be linked from the elementary school level to the high school level and to use them consistently in order to maximize their effects.

• Korean Chemical Engineering Research
• /
• v.51 no.6
• /
• pp.645-654
• /
• 2013

In this study, the management polices of micropollutants (MPs) were reviewed and the future management strategy was discussed considering climate change and etc. In Korea, the investigation of drinking water has been actively carried out for the priority contaminants as well as MPs. Recently river and lake waters have been also examined for MPs. However, the coverage and depth of the investigation is limited. Moreover, climate change is likely to increase air & water temperature and it will affect the hydrological cycle. Such changes may increase the residual concentrations of MPs in water system. As water reuse increases, the residual MPs of the recycled water may create public concerns. Thus, in a viewpoint of the precautionary principle, more stringent management of MPs is recommended for the drinking water and the body-contact water use. For the surface water, more studies are necessary to understand the ecological risk by MPs.

• Proceedings of the IEEK Conference
• /
• 2001.10a
• /
• pp.275-280
• /
• 2001

Typically, manganese (II) ions are incompletely removed from water as $MnO_2$ on increasing the pH of the water to 10. The water then has to be neutralized before it can be used. We propose a new and effective method for removing Mn (II) from water using a new combination of symbiotic microbes consisting of manganese-oxidizing bacteria and filamentous algae. The microbes rapidly oxidize Mn(II) to Mn (IV) at a neutral pH with no organic matter required as a nutrient and $MnO_2$is precipitated immediately. This differs from the use of heterotrophic manganese-oxidizing bacteria where organic nutrients are required. Our results suggest that this method will be useful in developing new systems for removal of manganese(II) ions from industrial and mining wastewater and drinking water. In addition, there are other possibilities such as recycling of dry batteries which are presently discarded without treatment