• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.1065-1070
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• 2001

The present age, it has been often reported that recycling of wasted glasses should be a great topic in related business circles. For the enviromental reasons, a public institution are looking for the ways of recycling these waste glasses. Consequently, the purpose of this research is to recycle crushed and powdered waste glasses by substituting for the cement in mortar and concrete. First of all, the optimum replacement ratio of Powdered Waste Glasses(PWG) can be obtained from the pilot test results. Secondary, we make advances in recycling of waste glasses as recycled to make secondary concrete products. So, we manufactured concrete brick and block contained powdered waste glasses by through mortar pilot test.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2001.11a
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• pp.58-63
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• 2001

Recently, it has been often reported that recycling of wasted glasses should be a great topic in related business circles. For the environmental reasons, a public institution are looking fur the ways of recycling these waste glasses. Consequently, the purpose of this research is to recycle crushed and powdered waste glasses by substituting for the cement in mortar and concrete. First of all, the optimum replacement ratio of Powdered Waste Glasses(PWG) can be obtained from the pilot test results. Secondary, we make advances in recycling of waste glasses as recycled to make secondary concrete products. So, we manufactured concrete brick and block contained powdered waste glasses by through mortar pilot test.

• Journal of Energy Engineering
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• v.26 no.1
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• pp.62-67
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• 2017

Limestone is an important commodity in Philippines. Limestone has numerous uses that range from agricultural applications to building materials to medicines. Many limestone products require rock with specific physical and chemical characteristics. Most limestone is biochemical in origin meaning the calcium carbonate in the stone originated from shelled oceanic creatures. In this paper, we reported the natural sources of limestone, geological formation of limestone and the oyster shell waste in Cebu, Bantayan, Philippines were reported. Due to the mining or quarrying in Cebu, Bantayan, in a limestone area poses the threat of groundwater pollution (since limestone is a porous geologic formation with a high transmissivity). The other environmental issue is oyster shell waste. The oyster shell waste is the major source of limestone. We developed and applied appropriate technologies for the extraction of limestone from oyster shell waste and utilizes as high value added material.

• Journal of Environmental Health Sciences
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• v.13 no.1
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• pp.17-33
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• 1987

As a result of technical advances and industrialization, the characteristics of domestic and industrial wastes are becoming more complex. Accordingly, improved treatment and disposal systems are being continuously sought to take account of complex characteristics and to comply with economic restrictions. In this study, an application of pyrolysis to the treatment of industrial wastes, including waste scrap rubber, waste raw material used in making the slipper bottom and waste PVC pipe, and the effectiveness of pyrolysis in resource recovery from these wastes were investigated. Batches of wastes were pyrolysed by external heating to a temperature of 400-800$\circ$C in a 32 mm diameter x 0.9 m long silica tube to produce combustible gases, oils and chars. Before the start of pyrolysis runs, the entire system was purged with nitrogen gas to exclude the air. The temperature inside the retort was controlled by the thermocouple in the gas stream, and referred to as the pyrolysis temperature. Under these conditions three products were separately collected and further analyzed. The results were summarized as follows. 1. More gases and less chars were produced with higher pyrolyzing temperature and with higher rates of heating, but the yields of oils tended downwards at temperatures above 700$\circ$C. Accordingly, operating conditions of pyrolysis should be varied with desired material. 2. Calorific values and sulfur contents of produced oils were sufficient and suitable for fuel use. Chars from waste rubber had high heating values with low sulfur contents, but calorific values of chars from waste PVC and waste slipper were as low as 3, 065-4, 273 kcal/kg and 942-2, 545 kcal/kg, respectively. Therefore, char from these wastes are inappropriate for fuel. 3. Soluble contents of Pb, Cd, Cu and Zn in chars from waste rubber and waste slipper were below the Specific Hazardous Waste Treatment Standards. However soluble contents of Pb and Cd in chars from waste PVC were one or two times and five or seven times exceedingly the Specific Hazardous Waste Treatment Standards, respectively. 4. Post high heating is desirable for treatment method of waste PVC which generates toxic hydrogen chloride. 5. The proportions of hydrogen, methane and ethane in produced gases were in the range of 3.99-35.61% V/V, 18.22-32.50% V/V and 5.17-5.87% V/V, respectively. 6. Pyrolysis is a useful disposal method in case of waste slipper, which was hardly combustible, and thus investigations of this kind of materials are required for effective management of industrial waste. 7. Based upon the possible market development for products, overall pyroly economics to take account of treatment values of noncombustible or hazardous materials should be evaluated.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.11b
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• pp.176-181
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• 2005

The electrolytic reduction process and the electrorefining process, which are being developed at the Korea Atomic Energy Research Institute (KAERI), are to generate molten waste salts such as LiCI salt and LiCI-KCI eutectic salt, respectively. Our goal in waste salt management is to minimize a total waste generation and fabricate a very low­leaching waste form such as a ceramic waste form. Zeolite has been known to one of the most desirable media to immobilize waste salt, which is water soluble and easily radiolyzed. Zeolite can be also used to the removal of fission products from the spent waste salt. Molten LiCI salt is mixed with zeolite A at $650^{\circ}C$ to form a salt-loaded zeolite, and then thermally treated in above $900^{\circ}C$ to become an immobilized product with crystal phase of $Li_{8}Cl_{2}$-Sodalite. In this work, a crystal phase changes of immobilization medium, zeolite, during immobilization of molten LiCI salt using zeolite A is introduced.

• Journal of the Korea Safety Management & Science
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• v.18 no.3
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• pp.9-15
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• 2016

Currently the forest area is 6,370,000 hectare (ha) which occupies 63.7% in Korea. The forest has good functions such as production of forest products, conservation of national land, prevention of disasters, etc. However constructing houses near the forest area make bad situation like illegal waste incineration by resident. So research subject is forest fire caused by waste incineration place including facility. And this study was conducted about statistical analysis and research analysis of the 100 waste incineration places including facilities at the country town. Statistical analysis shows that March is 27% which percentage is the highest number of forest fire in 10 years' average. The number of forest fire caused by waste incineration is 45 which is the third highest number in the fire statistic. The distance between waste incineration place including facility and forest area is 30m, 40m and 50m. That 40m (36%) is the most common distance from forest area. The types of waste incineration are ground (62%), the temporary facility made with oil drum can (35%) and other made with steel sheet, concrete, etc. The result of this study is that government and local government must conduct the improvement measure to reduce illegal incineration such as waste pickup area made with rain and wind proof type installed near residence, expenses for waste treatment, enlightenment and training, etc. Also considering their age and income are needed for realistic improvement.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.6
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• pp.839-846
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• 1994

Changing concepts in fishery science increasingly are recognizing depletion of traditional stocks, utilization of alternate(non-traditional) species, demand for high quality products, and a total resource utilization approach. Innovative practices are occurring in fisheries processing wherein solid and liquid discharges are no longer treated as 'waste,' but rather as valuable feedstocks for recovery of a variety of value-added ('value enhanced') by-products. Among these are protein hydrolysates, soluble proteins and amino acids, proteolytic enzymes, flavor and flavor extracts, pigments, and biopolymers such as chitosan. Properties and applications of this deacetylated derivative of chitin are noted. Crustacean processing by-products are discussed in terms of their serving as materials for generation of natural flavors and flavor extracts, and products such as fish sauces using contemporary enzymatic techniques. Various food and feed applications of fisheries processing by-products are illustrated with increased usage seen in formulated diets for an expanding aquaculture market. Examples are given of aquaculture becoming increasingly significant in global fisheries resource projections. Critical issues in the international seafood industry Include those of seafood quality, processing quality assurance (HACCP), and recognition of the nutritional and health-related properties of fisheries products. A variety of current seafood processing research is discussed, including that of alternate fish species for surimi manufacture and formulation of value-added seafood products from crawfish and blue crab processing operations. Increasing emphasis is being placed on international aspects of global fisheries and the role of aquaculture in such considerations. Coupled with the need for the aquatic food industry to develop innovative seafood products for the 21st century is that of total resource utilization. Contemporary approaches in seafood processing recognize the need to discard the traditional concept of processing 'waste' and adapt a more realistic, and economically sound, approach of usable by-products for food and feed application. For example, in a period of declining natural fishery resources it is no longer feasible to discard fish frames following fillet removal when a significant amount of residual valuable flesh is present that can be readily recovered and properly utilized in a variety of mince-based formulated seafood products.

• Textile Coloration and Finishing
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• v.7 no.2
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• pp.32-39
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• 1995

Various grades of hydroxyethyl cellulose (HEC, MS 0.65-3.20) were prepared throngh reaction of the knit-cotton-waste with ethylene oxide(EO). The knit-cotton-waste was composed of 98% of $\alpha$-cellulose and 2% of other components, and the cellulose was highly pure. The molar ratio of EO to knit-cotton-waste and that of NaOH to knit-cotton-waste, and the agitation speed were the important factors determining the molar substitution(MS) during the preparation of HEC. The MS of HEC was remarkably increased with increasing molar ratio of EO' to knit-cotton-waste. When the molar ratio of EO to knit-cotton-waste was 3.5, that of NaOH to knit-cotton-waste was 1.25, and agitation speed was 450rpm, it was possible to prepare HEC of MS 2.5. The structure and crystallinity of HECs prepared were determined by FT-IR and X-ray diffraction.

• Analytical Science and Technology
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• v.29 no.6
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• pp.300-304
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• 2016

The asphalt antistripping agents were synthesized from ethylenediamine (ED) or N,N'-bis(2-hydroxyethyl)ethylenediamine (HEED) with three different fatty acids. The formation of amide bonds were successfully performed and confirmed by FT-IR and $^1H-NMR$ data. The adhesive properties of antistripping agents were compared in terms of contact angle and BBS test. The reaction product of ED with waste animal fat exhibited the most hydrophobic by the contact angle measurement, and the strongest water resistance of 94 % by BBS test. However, the reaction product of ED with waste vegetable oil showed the strongest absolute bond strength of ca. 3610 and 3227 kPa for before and after water conditioning, respectively. For the bond strength in general, the reaction products of ED were superior to HEED reaction products, and the reaction products of animal fat and waste vegetable oil were superior to those of pure soybean oil.

• Elastomers and Composites
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• v.58 no.1
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• pp.32-43
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• 2023

The worldwide use of polyurethane foam products generates large amounts of waste, which in turn has detrimental effects on the surroundings. Hence, finding an economical and environmentally friendly way to dispose of or recycle foam waste is an utmost priority for researchers to overcome this problem. In that sense, the glycolysis of waste flexible polyurethane foam (WFPF) from automotive seat cushions using different industrial-grade glycols and potassium hydroxide as a catalyst to produce recovered polyol was investigated. The effect of different molecular weight polyols, catalyst concentration, and material ratio (PU foam: Glycols) on the reaction conversion and viscosity of the recovered polyols was determined. The obtained recovered polyols are obtained as single or split-phase reaction products. Besides, the foaming characteristics and physical properties such as cell morphology, thermal stability, and compressive stress-strain nature of the regenerated flexible foams based on the recovered polyols were discussed. It was observed that the regenerated flexible foams displayed good seating comfort properties as a function of hardness, sag factor, and hysteresis loss compared to the reference virgin foam. With the growing demand for a sustainable and circular economy, a global valorization of glycolysis products from polyurethane scraps can be realized by transforming them into profitable substances.