• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.805-812
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• 2009

Permeation water resulting in the reclaimed land of waste can possibly cause the second pollution, such as the underground water and environmental pollution. Accordingly, Liner layer has been installed in the reclaimed land of waste to block and purify permeation water and prevent this second pollution. The material used as Liner layer is the one for water resistance and that of less than permeability coefficient $1{\times}10^{-7}cm/sec$ is widely used. As it is very difficult to secure in bulk this natural clay with low permeability around the field, the suitable way to secure low permeable material is that we use blend with good watertighness by mixing it with natural soil which is spread in the site. While this mixed soil which can resist water is commonly used in the site, bentonite mixed soil which is widely used as Liner layer in the reclaimed land of waste is recognized in Liner and durability. In this study, the engineering characteristics of soil-bentonite mixed liner are investigated using the laboratory hydraulic conductivity and uni-axial strength tests. The soil used for the liner is the clay soil located near the site. Mixing ratio of the bentonite which satisfies the requirement of hydraulic conductivity is determined and the optimum mixing ratio of bentonite is recommended for the landfill. After the mixed liner is constructed using the optimum mixing ratio of bentonite, the block samples of the constructed liner are obtained and the strength tests were performed. The hydraulic and strength properties of the liner for construction of the waste landfill were both satisfactory.

• 상하수도학회지
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• 제25권1호
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• pp.15-21
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• 2011

Arsenic is one of the most abundant contaminant found in waste mine tailings, because of it's carcinogenic property, the countries like United states of America and Europe have made stringent regulations which govern the concentration of arsenic in drinking water. The current study focuses on different treatment methods for removal of arsenic from waste water. Treatment method the high strength arsenic waste water is treated with Fe(III)-ettringite by co-precipitation method. Number of experiments were carried out to decide the optimal dosage of Fe(III)-ettringite to treat arsenic waste water. The Fe(III)-ettringite was synthesized by taking appropriate equivalent ratios of calcium oxide and ferric chloride in proportion to the arsenic. The best removal efficiencies of 94% were observed at a As/(Ca: Fe) ratio of 1:3. The maximum removal of arsenic was observed in pH range of 12. But as the pH increases the arsenic removal efficiency decreases as portlandite is formed in the pH above 12. The analysis of surface of precipitate conform the needle like structure of ettringite. This treatment technique has promising features such as, the chemicals required in the treatment as well as the sludge generated can be reduced. The operating pH range is in alkaline region which is advantageous over traditional treatment process which has lower pH. Also the co-precipitation not only helps in removal of arsenic but also heavy metals.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1997년도 추계 국제학술심포지움 논문집
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• pp.3-31
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• 1997

Water has always played a significant role in the lives of people. In urbanised Rome, with its million people. sophisticated supply systems developed and then fled with the empire. only to be rediscovered later But it was the industrial Revolution commencing in the eighteenth century that ushered in major paradigm shifts In use and altitudes towards water. Rapid and concentrated urbanisation brought problems of expanded demands for drinking supplies, waste management and disease. The strategy of using water from local streams, springs and village wells collapsed under the onslaughts of rising urban demands and pollution due to poor waste disposal practices. Expanding travel (railways. and steamships) aided the spread of disease. In England. public health crises peaks, related to water-borne typhoid and the three major cholera outbreaks occurred in the late eighteenth and early nineteenth century respectively. Technological, engineering and institutional responses were successful in solving the public health problem. it is generally accepted that the putting of water into pipe networks both for a clean drinking supply, as well as using it as a transport medium for removal of human and other wastes, played a significant role in towering death rates due to waterborne diseases such as cholera and typhoid towards the end of the nineteenth century. Today, similar principles apply. A recent World Bank report Indicates that there can be upto 76％ reduction in illness when major water and sanitation improvements occur in developing countries. Water management, technology and thinking in Australia were relatively stable in the twentieth century up to the mid to late 1970s. Groundwater sources were investigated and developed for towns and agriculture. Dams were built, and pipe networks extended both for supply and waste water management. The management paradigms in Australia were essentially extensions of European strategies with the minor adaptions due to climate and hydrogeology. During the 1970s and 1980s in Australia, it was realised increasingly that a knowledge of groundwater and hydrogeological processes were critical to pollution prevention, the development of sound waste management and the problems of salinity. Many millions of dollars have been both saved and generated as a consequence. This is especially in relation to domestic waste management and the disposal of aluminium refinery waste in New South Wales. Major institutional changes in public sector water management are occurring in Australia. Upheveals and change have now reached ail states in Australia with various approaches being followed. Market thinking, corporatisation, privatisation, internationalisation, downsizing and environmental pressures are all playing their role in this paradigm shift. One casualty of this turmoil is the progressive erosion of the public sector skillbase and this may become a serious issue should a public health crisis occur such as a water borne disease. Such crises have arisen over recent times. A complete rethink of the urban water cycle is going on right now in Australia both at the State and Federal level. We are on the threshold of significant change in how we use and manage water, both as a supply and a waste transporter in Urban environments especially. Substantial replacement of the pipe system will be needed in 25 to 30 years time and this will cost billions of dollars. The competition for water between imgation needs and environmental requirements in Australia and overseas will continue to be an issue in rural areas. This will be especially heightened by the rising demand for irrigation produced food as the world's population grows. Rapid urbanisation and industrialisation in the emerging S.E Asian countries are currently producing considerable demands for water management skills and Infrastructure development. This trend e expected to grow. There are also severe water shortages in the Middle East to such an extent that wars may be fought over water issues. Environmental public health crises and shortages will help drive the trends.

• 대한화학회지
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• 제58권4호
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• pp.359-365
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• 2014

The inhibition effect of cinnamon plant extract as a green corrosion inhibitor for steel in sulfide polluted salt water was studied by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and electrochemical frequency modulation (EFM). The results showed that cinnamon plant extract in sulfide polluted salt water is a good corrosion inhibitor with inhibition efficiency reached to 80% at 250 ppm of the plant extract. The adsorption of cinnamon obeys Temkin adsorption isotherm, and acts as a mixed-type of inhibitor but dominantly as a cathodic inhibitor in sulfide polluted salt water.

• 환경영향평가
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• 제12권3호
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• pp.161-170
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• 2003

To investigate the characteristics of 17 solid waste landfills in the upper drainage basin of Lake Daechong, the landfill sites were surveyed, the leachate of these landfills were analyzed, and the analysis results were assessed from standpoint of water contamination. Sanitary landfills which are now being operated are relatively well equipped with facilities such as leachate collection, daily soil cover and landfill gas treatment devices. But a few of open-dumping landfills were leaking leachate apparently and were supervised improperly and neglectfully by local governments. Some of sanitary landfills exceeded the COD permission criteria of leachate effluent, and some of open-dumping landfills exceeded SS, T-P, Pb, As, Fe, Mn permission criteria of leachate effluent. To improve the water quality of Lake Daechong which is utilized for supplying drinking water, agricultural water, and industrial water to the great part of Chungchong area, the adequate and prompt measures for preventing Daechong Lake water contamination from landfills leachate is necessary.

• Environmental Analysis Health and Toxicology
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• 제16권4호
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• pp.153-159
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• 2001

The main point source of pollution of the Keumho river in Taegu, Korea, stems from waste from the areas of industrial complexes . Although it is widely accepted that pollutants in waste water negatively effects general water quality, it is difficult to evaluate the effluent effect because of varying conditions in ambient water and inconclusive knowledge of causative pollutants. To analyze the water in relation to the industrial effluent in the area, pH. temperature, conductivity, and Microtox toxicity of various river samples were measured. Water samples were collected every 2 hours for 36 hours from Keumho river and Dalseo stream. Data from continuous monitoring for 36 hours showed that effluent in Keumho river originated from Dalseo stream, which is near adjacent to industrial complexes. Change in toxicity and other factors tested during the 36 hours indicated that continuous monitoring was necessary for a satisfactory effluent toxicity test Furthermore, in addition to water quality monitoring, it was concluded that sediment toxicity also needed to evaluate effluent effects.

• 한국막학회:학술대회논문집
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• 한국막학회 1998년도 제6회 하계 Workshop (98 한국막학회, 국립환경연구원 국제 Workshop, 수자원 보전과 막분리 공정)
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• pp.81-94
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• 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.

• International Journal of Air-Conditioning and Refrigeration
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• 제6권
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• pp.168-176
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• 1998

A simulation study was conducted to use city-water which is thermally regulated by unused energy as a heat source for urban dwellings. This study utilized multiple heat pump system using the city-water as a heat source and suggested a method of reducing the heat load of hot water supply. The simulation was done to calculate the energy savings at a dwelling for a year. The relation between the controlled temperature of city-water. and electric energy in all seasons was also investigated. Furthermore, it has been found that the controlled water system can lead to considerable energy savings and decrease environmental load such as sensible waste heat which otherwise would form heat islands.

• 한국식품영양과학회지
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• 제28권3호
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• pp.747-754
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• 1999

Food waste in school foodservices is an important factors in managing expense and in evaluating the acceptance of served meals. This study was undertaken to investigate the management of food waste and the opinion of dietitians in one hundred fourty nine elementary school foodservices, in Pusan, Korea. When serving places were compared, the classroom generated more leftover and plate waste than those of lunchroom(p<0.05). In rank for generating raw waste, the residue from vegetables was the highest in first order. Fruit, eggs, fish, and shell fish also left the most raw waste, respectively, in descending order. The residue that generated the most plate waste in the first and the second order was from soup and pot stew, and vegatables side dishes, respectively. The treatment process of food waste which was the most common in school foodservices was the fertilization by processing machine in order to make recyclable fertilizer(52.1%). Food waste at 30.8% of foodservices was processed for live stock feed. At 92.3% of investigated foodservices, food waste water was drained through a round net basket. Before treating as a waste, food residue was recycled at only 41.9% of foodservices. The main utilization of food residue was the production of soap from used oil. Most dietitians in school foodservices recognized that treating food waste was not so inconvenient, although, the problems of odor and hygiene were not solved. They also thought that the liquid residue(54.1%) and oil(30.4%) among food waste were primarily responsible for resulting environmental pollution.

• Environmental Engineering Research
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• 제8권3호
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• pp.152-161
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• 2003