• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.2 s.115
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• pp.61-71
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• 2006

Environment-friendly shock-absorbing (cushioning) materials were made using a vacuum forming method from waste wood collected from local mountains in Korea. The waste wood was pulped by thermomechanical pulping. The TMP cushions showed superior shock-absorbing properties with lower elastic moduli compared to EPS(Expanded Polystyrene) and pulp mold. Even though the TMP cushions made using at different suction times had many free voids in their inner fiber structures, their apparent densities were a little higher than EPS and much lower than pulp mold. The addition of cationic starch improved elastic modulus of the TMP cushions without increasing the apparent density, which was different from surface sizing with starch. The porosity of the TMP cushions was a little greater than EPS and much less than pulp mold. Finally, the TMP cushions have great potential to endure external impacts occurring during goods distribution.

• Applied Chemistry for Engineering
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• v.30 no.6
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• pp.707-711
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• 2019

The feasibility of waste concrete as a catalyst for the effective pyrolysis of polyethylene terephthalate (PET) was examined using thermogravimetric (TG) and pyrolyzer-gas chromatography/mass spectrometry (Py-GC/MS) analyses. TG analysis results indicated that the maximum decomposition temperature of PET is not altered by the use of waste concrete, showing similar values (407 ℃ and 408 ℃ at 5 ℃/min). Meanwhile, the volatile product distribution data obtained from the Py-GC/MS analysis revealed that the use of waste concrete promoted the deoxygenation reaction via converting the oxygen containing products such as benzoic acids, benzoates, and terephthalates to valuable deoxygenated aromatic hydrocarbons including benzene, toluene, ethylbenzene, and styrene. This suggests that the waste concrete can be used as a potential catalyst for the production of valuable aromatic hydrocarbons from PET pyrolysis.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.3
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• pp.42-47
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• 2008

For the purpose of reduction of production cost in the industrial papermaking process, the use of waste paper has been more and more increased as a fibrous raw material, and the closed system of white water became closed more than ever. "Scum" indicates the floated sludge by a flotation during primary wastewater treatment process in paper mills. If the scum is used as the raw material, it could reduce both the raw material and solid waste treatment cost with even small quantity. In this study, the element survey and the toxicity measurement was carried out for recycling scum. A load factor of stock preparation process in paper mills was measured by somerville screen. Physical properties of paper sheet containing the accepted scum from the stock of AOCC or KOCC were evaluated. The result of this study shows that recycling scum has potential to be used in paper making system. It also might be able to reduce the required energy used by the pressing or drainage process, the raw material cost, and solid waste treatment cost due to the recycling of scum.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.841-846
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• 2002

As growing of industrialization and increasing of population. the quantities of waste are rapidly growing in the earth. It cause some problems such as the waste of natural resources and environmental pollution. In this context, recycling waste glass as a material of concrete has a great advantage environmentally and economically. On that score, other contries have start recycling waste glass widely and accoumulatig the technology of manufacturing equipment and construction. However, few studies have been done in this country. Therefore, this study was conducted freeze-thaw resistance test and neutralization reaction test to analyze the durability properties of steel fiber reinforced concrete containing waste glass as fine aggregate and containing industrial by-products(Fly ash).

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.593-598
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• 2002

Recently, as industrialization is rapidly growing and the standard of life is rising, the quantities of waste glasses have been hastily increased and most of them are not recycled but abandoned. It causes some problems such as the waste of natural resources and environmental pollution. Therefore, in this study freeze-thaw resistance test was conducted to analyze the properties of concrete containing waste glasses as fine aggregates and containing industrial by-products (fly ashes, silica fumes). As a results, it was found that freeze-thaw resistance decreases as the content of waste glasses increases. Also, the content of fly ash doesn't affect to the freeze-thaw resistance, and freeze-thaw resistance decreases with tile increase of silica fume contents.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.11b
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• pp.79-83
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• 1999

A cationic demand(CD) is a very useful indication for determining the optimum dosage rate of retention aids to the papermaking stock at the wet end. Polyelectrolyte titration has been most often used to determine a CD. Highly accurate results can be obtained by this method when the ionic strength of sample is low. But this is accompanied by the serious errors when the ionic strength is higher than that corresponding to 20 milli molar(mM) monovalent, 2 mM divalent or 0.2 mM trivalent ions because of no occurrence of the end point of titration. Therefore, it is very difficult or almost impossible for the conventional method to be applied to the industrial suspensions such as papermaking stock and industrial waste water. Then a novel method using chromophoric labeled cationic polymer which can be applicable to the sample with high ionic strength has been developed.

• Journal of the Korean Ceramic Society
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• v.53 no.4
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• pp.444-449
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• 2016

Industrial by-products generated by integrated iron and steel manufacture cause environmental pollution. The by-products contain not only iron element but also harmful substances. Therefore, in view of to waste recycling and environmental preservation, production of sponge iron using the by-product is considered an effective recycling method. In this study, reduction efficiency of pellets from blast furnace dust was measured. Metallization was found to be increased, as $C/Fe_{total}$ ratio and reaction time were increased. The pellets were formed into a globular shape, and calcined for 60 minutes at $1100^{\circ}C$ in an electric furnace. Phase changes were analyzed using an X-ray diffractometer. Microstructures of the pellets were observed by a scanning electron microscope.

• Asian Journal of Turfgrass Science
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• v.5 no.2
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• pp.81-86
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• 1991

The sludge, a waste of brewery industries, was examined for potentials as a natural organic fertilizer (or soil conditioner) for lawn. Trial products were measured for changes of physical, chemical properties in laboratory and seed germination and seedling growth in green house were also tested. The results are as the following:1The sludge from distilled liquor brewery contained high quantity of organic matter which had proper physical and chemical properties for lawn fertilizer (natural organic fertilizer, soil conditioner, top-dressing mix) . It showed good characteristics in handling and capabilities to be developed as commercial products for golf courses. 2.Sludge from beer company needs proper treatment to improve physical properties for futher degradiation. It is because aggregation of the sludge particles prevented microbial activities and changing to soluble form. 3.Green carbon can be used as carbon source for organic fertilizer production using brewery sludge, but it should not contain wood extract which inhibit seed germination and seedling growth.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.6
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• pp.128-135
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• 2003

This study is performed to examine the physical and mechanical properties of concrete using recycled aggregate and industrial by-products. The test results show that the unit weight, compressive and flexural strength, ultrasonic pulse velocity and dynamic modulus of elasticity are decreased with increasing the content of recycled aggregate. But, the absorption ratio is increased with increasing the content of recycled aggregate. The unit weight is 2,237∼2,307 kg/$\textrm{m}^3$, the absorption ratio is 2.96∼4.12%, the compressive strength is 415∼532 kgf/$\textrm{cm}^2$, the flexural strength is 75∼96 kgf/$\textrm{cm}^2$, the ultrasonic pulse velocity is 4,350∼4,949 m/s and the dynamic modulus of elasticity is $390\times10^3\;∼\;465\times10^3$ kg f/$\textrm{cm}^2$, respectively These recycled aggregate concrete can be used for high strength concrete.

• Journal of Applied Reliability
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• v.10 no.3
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• pp.199-211
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• 2010

Recycling involves processing used materials into new products and remanufacturing is an industrial process in which worn-out products are restored to like-new condition. Recycling and remanufacturing industry is environmentally and economically important industry and provides significant benefits to prevent waste of potentially useful materials and reduce energy usage. The purpose of this research is to investigate the trend of recycling and remanufacturing industry in Korea and other countries like Germany, Japan and America. The yield information is generally quite valuable to promote green growth industry as an important alternative in the 21st century.