• Resources Recycling
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• v.19 no.6
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• pp.36-42
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• 2010

Researches on resources recycling in the field of construction have made an extensive progress such as recycled aggregate of waste concrete and recycling of asphalt. On the other hand, there are almost never researches on pavement method with used waste frying oil. In South Korea, 0.2 million ton used waste frying oil is discharged every year. It is guessed that about 0.1 million ton used waste frying oil can be collected. If used waste frying oil is recycled, it is expected that disuse cost will be reduced and water pollution of rivers will be prevented. Therefore, the purpose of the study was to evaluate on mechanical features (strength, water resistance, chemical resistance, abrasion resistance, freezing and thawing resistance and permeable coefficient) whether dense graded permeable concrete mixing silica sand with flexible alkyd resin manufactured by making ester reaction with collected used waste frying oil to make alkyd resin could be applied to road pavement for non-roadway. The results of the study were as follows. In flexural strength, it had 1.6 times as much as road design standard 4.5MPa. In water resistance, chemistry resistance and freezing and thawing resistance, they had lack of strength in early age. As age went by, they didn't have large changes. And curing temperature had phenomenon of increase in strength at rather low temperature than high temperature by glass transition temperature of resin. Therefore, considering workability, strength and durability when it was applied to road pavement, it was reasonable that the mixing ratio of flexible alkyd resin was 10~15% in comparison with silica sand weight.

• Applied Chemistry for Engineering
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• v.7 no.6
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• pp.1164-1173
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• 1996

Treating methods and characteristics of waste from a nuclear fuel powder conversion plant were studied. To recovery or treat a trace uranium in liquid waste, the ammonium uranyl carbonate(AUC) filtrate must be heated for $CO_2$ expelling, essentially. Uranium content of final treated waste solution from fuel powder processes for a heavy water reactor(HWR) could be lowered to 1 ppm by the lime treatment after the ammonium di-uranate(ADU) precipitation by simple heating. Otherwise, in case of the waste from fuel powder processes for a pressurized light water reactor(PWR), it is result in 0.8 ppm as a form of uranium peroxide such as $UO_4{\cdot}2NH_4F$ compounds. Optimum condition was found at $101^{\circ}C$ by the simple heating method in case of HWR powder process waste. And in case of PWR powder process waste, optimum condition could be obtained by precipitating with adding hydrogen peroxide and adjusting at pH 9.5 with ammonia gas at $60^{\circ}C$ after heating the waste In order to expelling $CO_2$. As the characteristics of recovered uranium compounds, median particle size of ADU was increased with pH increasing in case of HWP waste. Also, in case of uranium proxide compound recovered from PWR waste, the property of $U_3O_8$ power obtained after thermal treatment in air atmosphere was similar to that of the powder prepared from AUC conversion plant.

• Journal of Navigation and Port Research
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• v.27 no.3
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• pp.259-266
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• 2003

Due to the growth of population and industrial development at the coastal cities, there has been much increase in necessity to effective control of the wastes into the coastal water and river. The amount of disposal at those waters has been increased rapidly ana it is necessary for us to track of it in order to keep the waterway safe and the water clean. The investigation and research in terms of water quality in these regions have been conducted frequently but the systematic survey of the disposed wastes at the bottom was neglected and/or minor. In this study we surveyed the status of disposed waste distribution at the bottom of coastal water and river from the scanned images. The intensity of sound received by the side scan sonar tow fish from the sea floor provides information as to the general distribution and characteristics of the superficial wastes. The port and starboard side scanned images produced from two arrays of transducers borne on a tow fish connected by tow cable to a tug boat have the area with width of 22m~112m and band of 44m~224m. All data are displayed in real-time on a high-resolution color display ($1280{\times}1024$ pixels) together with position information by DGPS. From the field measurement and analysis of the recorded images, we could draw the location and distribution of bottom disposals. Furthermore, we could make a database system which might be useful for navigation and fundamental for planning the waste reception and process control system.

• The Journal of Engineering Geology
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• v.16 no.4 s.50
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• pp.351-357
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• 2006

Recently there is increasing the flow of hazardous chemical substances caused by industrial waste waters into a main river. It is needed to make the high treatment in drinking water treatment plants for reducing a health risk. Therefore, the monitoring of trace hazardous chemical substances by the industrial waste water inflow is available increasing economical efficiency of river management as well as reduction of risk. In this study, the most important substance among numerical and quantitative trace hazardous chemicals is Hexachlorobutadiene in an effluent of industrial wastes. However all items of GroupII which was included with semiconductor, electricity/electron and metal assemble was not detected. It means that we must consider the characteristics and behavior of load pollutants to water resources to select monitoring items. That was called 'preparatory monitoring'. We can reduce an economical consumption as well as risks from these pollutants using the preparatory monitoring.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.2
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• pp.135-142
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• 2010

To obtain the input data for the design and long-term performance assessment of a high-level waste repository, the thermal conductivities of several granite rocks which were taken from the rock cores from the declined borehole were measured. The thermal conductivities of granite were measured under the different conditions of water content to investigate the effects of the water content on the thermal conductivity. A simple empirical correlation was proposed to predict the thermal conductivity of granite as a function of effective porosity and water content which can be measured with relative ease while neglecting the possible effects of mineralogy, structure and anisotropy. The correlation could predict the thermal conductivity of granite with the effective porosity below 2.7% from the KURT site with an estimated error below 10%.

• Journal of Hydrogen and New Energy
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• v.34 no.4
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• pp.327-333
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• 2023

The water gas shift reaction was carried out using the commercial catalyst pellet and the simulated gases expected to occur from waste plastic gasification. In the water gas shift reaction, the high temperature shift reaction and the low temperature shift reaction were continuously performed with CO:H₂O ratio of 1:2, 1:2.5, and 1:3, and the CO conversion and H₂ increase rate were evaluated. The H₂ increase rate increased in order to CO:H₂O ratio of 1:3 > CO:H₂O ratio of 1:2.5 > CO:H₂O ratio of 1:2. The CO conversion showed a high value of more than 97% at each CO:H₂O ratio. The water gas shift reaction at a CO:H₂O ratio of 1:3 showed the highest H2 increase rate and CO conversion.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.6
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• pp.56-71
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• 2003

Waste landfills have been the center of environmental problems and they must be restored due to environmental pollution, disgusting landscape, and cost of management. It is suggested that they be recycled urban space as cities expand. Specially, nonsanitary waste landfills which have no pollution prevention facilities cause serious problems. Restoring the landfills as parks and golf courses, so on makes more benefits because of cheap use land, closeness to urban area, flat topography applicable to parks and golf courses, and high land values after restoration and the changes to local recreation sites. Restoration of waste landfills is a complex, costly, and interdisciplinary work. But, the waste landfill is a manmade ecosystem. Control, restoration and postmanagement of waste landfills are very important problems. The role of vegetation prevents soil erosion, reduces soil water storage, and obstructs leachate seepage. Early restoration makes derelict lands into man park artificially geared to soil, vegetation, landforms and hydrology. But, Ideal restoration is to make stable ecosystem nature-friendly and compatible with surrounding landscape without more management. Landscape is structured hierarchically with patches and stands as small components and forms forest as large components. Therefore, landscape formation of the waste landfills needs much restoration process. There are many ecological restoration techniques for the waste landfills. Those are divided into artificial and natural methods. The artificial method is anthropogenic plantings while the natural method is to trigger and use succession processes. The most important thing in the restoration of waste landfills is to consider the final restoration objectives of each waste landfill. According to these objectives, the depth of covering layer, planting degree, and structural design should be determined. The effective restoration methods should be selected of artificial and natural options.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.6
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• pp.682-688
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• 2016

Food waste has recognized one of useful sources for potentially agricultural application to supply organic matter and nutrients in arable soil. However, there was little information on application of food waste compost related to the maturity and NaCl content in arable soil. This study evaluated the effect of food waste compost application on yield and fertility in soil under flooding and upland condition. The yields in rice and pepper cultivation decreased with increasing the rate of food waste compost application in soil (p<0.05). Maximum yields of rice ($49.0g\;plant^{-1}$) and pepper ($204g\;plant^{-1}$) were shown at 10 and $30Mg\;ha^{-1}$ of food waste compost application, respectively. The N, P, and K contents in grain and plant residues increased by the application of food waste compost, there was no difference on Na/K ratio in plant tissue among the treatments. Application of food waste compost resulted in the increase of pH, EC, TC, available P contents in soil after crop harvest, especially, which was shown the increase of the CEC and exchangeable sodium percentage (ESP) contents in irrespective of water condition. In conclusion, application of food waste compost in soil was effective on the supply of the organic matter and nutrient. However, it might need caution to apply food waste compost for sustainable productivity in arable soil because of potential Na accumulation.

• Journal of the Korea Convergence Society
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• v.11 no.7
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• pp.79-87
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• 2020

The environmental problems caused by food waste have been a steady social issue, and the severity of the problem emerged as the 2013 London Convention banned the marine emissions of waste water. The government implemented measures related to food waste, but prior studies showed that it lacked continuity and lacked strategies for each area of occurrence, and emphasized that citizens' participation is important to implement effective reduction policies. Therefore, this study proposed a food waste disposal machine through user experience analysis as a way to induce civic participation. To this end, the design development direction was outlined in this study after the pre-research and user survey stages through FGI and user journey maps. Based on this, the proposed treatment machine facilitates the frequent discharge of waste and simplifies the process of food waste in the home. In addition, the moment of direct contact between the user and waste is only the point at which the waste is released to the handler, thereby minimizing the negative experience the user has experienced.

• Smart Structures and Systems
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• v.22 no.4
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• pp.433-440
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• 2018

Pavements porous concrete is a noble structure design in the urban management development generally enabling water to be permeated within its structure. It has also capable in the same time to cater dynamic loading. During the technology development, the quality and quantity of waste materials have led to a waste disposal crisis. Using recycled materials (secondary) instead of virgin ones (primary) have reduced landfill pressure and extraction demanding. This study has reviewed the waste materials (Recycled crushed glass (RCG), Steel slag, Steel fiber, Tires, Plastics, Recycled asphalt) used in the pavement porous concretes and report their respective mechanical, durability and permeability functions. Waste material usage in the partial cement replacement will cause the concrete production cost to be reduced; also, the concretes' mechanical features have slightly affected to eliminate the disposal waste materials defects and to use cement in Portland cement (PC) production. While the cement has been replaced by different industrial wastes, the compressive strength, flexural strength, split tensile strength and different PC permeability mixes have depended on the waste materials' type applied in PC production.