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Daegu, South Korea

Kim Y.,EB Technology Co. | Kim J.,EB Technology Co. | Han B.,EB Technology Co. | Choi J.-S.,Korea Dyeing Technology Center | Lee M.-J.,Korea Atomic Energy Research Institute
Journal of the Korean Physical Society | Year: 2011

Textile dyeing processes consume a great amount of water and steam and discharge filthy and colored wastewater. Increased use of assorted dyes and other chemicals has increased the pace of reequipping purification facilities by applying efficient methods based on radiation technology. Based on laboratory data, a pilot-scale e-beam plant was constructed at the Daegu Dyeing Industrial Complex (DDIC) in 1998. An electron accelerator, 40 kW at 1 MeV, was used for 1,000 m3 per day. Continuous operation of this plant showed that the preliminary e-beam treatment reduced the bio-treatment time and resulted in significant decreases in the TOC (total organic carbon), CODCr (Chemical Oxygen Demand as dichromate method), and BOD5 (Biochemical Oxygen Demand in 5 days). Convinced of the economics and efficiency of the process, a commercial plant with a 400-kW electron accelerator was constructed in 2005. This plant improved the removal efficiency of wastewater by decreasing the retention time in a bio-treatment facility with a dose of approximately 1 kGy. This plant is located in the vicinity of an existing wastewater treatment facility in the DDIC, and the treatment capacity is 10,000 m3 of wastewater per day. Source

Son Y.-S.,Harvard University | Son Y.-S.,Konkuk University | Kim P.,Konkuk University | Park J.H.,Korea Dyeing Technology Center | And 2 more authors.
Plasma Chemistry and Plasma Processing | Year: 2013

To identify the decomposition characteristics of trimethylamine (TMA) by electron beam (EB), we conducted an experiment based on process parameters, including absorbed dose (2.5-10 kGy), background gas (air, O2, N 2 and He), water content (1,200, 14,300, and 27,500 ppm), initial concentration (50, 100, and 200 ppm) and reactor type (batch or continuous flow system). Air background gas showed a maximum TMA removal efficiency of 86 % at 10 kGy and that was the highest efficiency of all background gases. Energy efficiencies were higher when the absorbed dose was lower (e.g., 2.5 kGy). Decomposition efficiencies of all initial TMA concentrations were approximately >90 % at 10 kGy. Removal efficiencies increased up to 30 % as water vapor increased. As a by-product, it is observed that CH3 radical formed by EB irradiation was converted into CH4 by reaction with residual TMA, (CH3)2NH, and H. These results suggest that EB technology can be applied for TMA treatment under low concentration and high flow rate conditions. © 2013 Springer Science+Business Media New York. Source

Karim M.R.,Kyungpook National University | Lee H.W.,Kyungpook National University | Woo C.,Kyungpook National University | Park S.M.,Korea Dyeing Technology Center | And 2 more authors.
Polymer Composites | Year: 2010

Conducting polyaniline (PAni)-titanium dioxide (TiO2) nanocomposites have been synthesized by the inverted emulsion polymerization method. Aqueous mixtures of aniline, a free-radical oxidant, and/or TiO 2 nanopar- ticles (∼25 nm in diameter; mixture of anatase and ru- tile) are utilized to synthesize the hybrid nanocompo-sites. The polymerization is carried out in an organic solvent (chloroform, CHCl3) in the presence of a pro- tonic acid (hydrochloric acid, HCl) as a dopant and an emulsifier (cetyl trimethylammonium bromide). The resultant PAni-TiO2 nanocomposites are characterized with their structural, morphological, conducting, and optical properties. SEM and TEM images represent the PAni-TiO2 nanocomposites with the diameter range of 50-200 nm. Electrical conductivities are checked by standard four-point probes method and found to be 0.38 S/cm for bulk PAni and 0.11 S/cm for PAni-TiO2 nanocomposites. UV-visible absorption shows two electronic bands at about 320 and 596 nm for bulk PAni and the blue-shifted bands with the intensity changes due to the formation of PAni-TiO2 composites. Thermogravimetric analysis reveals that the composites have a higher degradation temperature than the PAni alone. POLYM. COMPOS., 31:83-88, 2010. © 2009 Society of Plastics Engineers. Source

Park J.H.,Kyungpook National University | Park S.M.,Korea Dyeing Technology Center | Kim Y.H.,Kyungpook National University | Oh W.,Dong - Eui University | And 4 more authors.
Journal of Composite Materials | Year: 2013

Zein is a hydrophobic protein produced from maize and has great potential in a number of industrial applications such as food, food coating and food packaging. The objectives of this study are to determine the effects of montmorillonite on the wettability and microstructure properties of zein/montmorillonite nanocomposite nanofiber mats fabricated by the electrospinning technique in ethyl alcohol aqueous solution. The zein/montmorillonite nanofiber mats were characterized by field-emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis and contact angle measurements. This study shows that the introduction of montmorillonite resulted in the improvement of the thermal stability and hydrophilicity for the zein matrix. X-ray diffraction patterns and transmission electron microscopy micrographs suggest the coexistence of intercalated montmorillonite layers over the examined montmorillonite contents. Since montmorillonite is a hydrophilic clay, its addition can be used not only to produce nanomaterials with the already known improved properties but also to enhance the hydrophilicity of material. © The Author(s) 2012 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav. Source

Han B.,EB Technology Co. | Kim J.,EB Technology Co. | Kang W.,EB Technology Co. | Choi J.S.,Korea Dyeing Technology Center | Jeong K.-Y.,Kongju National University
Radiation Physics and Chemistry | Year: 2016

Due to the necessity of pilot scale test facility for continuous treatment of wastewater and gases on site, a mobile electron beam irradiation system mounted on a trailer has developed. This mobile electron beam irradiation system is designed for the individual field application with self-shielded structure of steel plate and lead block which will satisfy the required safety figures of International Commission on Radiological Protection (ICRP). Shielding of a mobile electron accelerator of 0.7 MeV, 30 mA has been designed and examined by Monte Carlo technique. Based on a 3-D model of electron accelerator shielding which is designed with steel and lead shield, radiation leakage was examined using the Monte Carlo N-Particle Transport (MCNP) Code. Simulations with two different versions (version 4c2 and version 5) of MCNP code showed agreements within statistical uncertainties, and the highest leakage expected is 5.5061×10-01 (1±0.0454) μSv/h, which is far below the tolerable radiation dose limit for occupational workers. This unit could treat up to 500 m3 of liquid waste per day at 2 kGy or 10,000 N m3 of gases per hour at 15 kGy. © 2015 Elsevier Ltd. Source

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