• Journal of Korea Soil Environment Society
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• v.2 no.2
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• pp.53-60
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• 1997

A series of batch and lab-scale pilot tests were conducted to optimize the design parameters for the application of soil washing techniques to the soil contaminated by heavy metals. Cu, Pb, and Zn were selected as target heavy metals. The concentrations of Cu, Pb, and Zn were 500mg/kg dry soil, 1, 000mg/kg dry soil, and 500mg/kg dry soil, respectively. Citric acid and oxalic acid were used for the extractants. In the batch tests, the extraction efficiencies for Cu, Pb, and Zn were 79%, 72%, 72%, respectively. The proper extractant concentration and dilution ratio(weight/volume) for Cu and Pb were turned to be citric acid 50mM and 1:5, respectively. The extraction efficiencies were enhanced with the addition of 1~2% OA-5 or SDS. From pilot scale tests for Pb, first stage and second stage of soil washing resulted in the extraction efficiency of 59% and 78%, respectively.

• Journal of Soil and Groundwater Environment
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• v.10 no.1
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• pp.58-64
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• 2005

Several tests were conducted to determine the optimum operational conditions of soil washing techniques for floe-forming arsenic-contaminated soils, collected from D abandoned Iron-mine in Korea. The optimum cut-off size was 0.15 mm $(sieve\;\#100)$, about $94\%$ of the mass of soils. Both sodium hydroxide and hydrochloric acid were effective to remove arsenic and the optimum mixing ratio (soil [g] : washing solution [mL]) was 1:5 for both washing agents. Arsenic concentrations, determined by KST Methods, for the dried floe solids obtained from flocculation at pH 5-6 were $990\~1,086\;mg/kg$ dry solids, which were higher concentrations than at the other pH values. Therefore, batch tests for sequential washings with or without removing floc were conducted to find the enhancement of washing efficiencies. After removing floe with 0.2 M HCl, sequential washings of 1 M HCl followed by 1 M NaOH showed the best results (15 mg/kg dry soil). The arsenic concentrations of washing effluent from each washing step were about $2\~3\;mg/L$. However, when these acidic and basic effluents were mixed together, arsenic concentration was decreased to be less than $50\;{\mu}g/L$, due to the pH condition of coagulation followed by precipitation for arsenic removal.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1525-1529
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• 2009

Washed ballast is used on paved track to earn the high quality track performance. But, the water washing system caused the several environment problems such as the noise, dust and water pollution. Even if the washing is performed, it is difficult to earn the high quality because of the low efficiency of the water washing system. So, we developed the dry cleaning type machine to solve these problems. This machine excludes using the water completely. Especially, it is possible to organize on the conventional ballast cleaning train set.

• The Korean Journal of Ceramics
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• v.7 no.1
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• pp.16-19
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• 2001

For the fast dry of the aqueous tape, the process which water was reaplaced by organic solvent was proposed. Socalled, it was the solvent washing dry. Three organic solvents (methanol, ethanol and acetone) were selected for the washing solvent. The weight loss of the washed tapes was measured to evaluate the dry rate of the tapes and dried tapes were examined the generation of the cracks with the variations of the organic solvent and the washing time. Methanol, ethanol and acetone were available organic solvents for this method. The tapes washed in methanol, ethanol and acetone were dried rapidly for twenty minutes. After thirty minutes, the weight losses were not found any more, The solvent of the lower surface tension can decreases the crack of dried tape. If solvent substitutes water completely, though it was fast dried, crack can be eliminated.

• The Research Journal of the Costume Culture
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• v.16 no.1
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• pp.158-165
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• 2008

The purpose of this study was to investigate the dyeing property and ultraviolet-cut ability on silk 100% and nylon 100% fabrics dyed with Rhus verniciflua extracts. This study was investigated K/S values, surface color, washing fastness, dry cleaning fastness and ultraviolet-cut ability of the silk and nylon fabrics dyed with Rhus verniciflua extracts under the various dyeing conditions. As mordanting were used Tin(II) Chloride dihydrate $(SnCl_2{\cdot}2H_2O)$, Copper(II) sulfate pentahydrate$(CuSO_5{\cdot}5H_2O)$, Iron(II)Chloride$(FeC_2{\cdot}4H_2O)$. pH was adjusted by sodium carbonate$(Na_2CO_3)$ and formic acid(HCOOH). The optimum dyeing temperature, dyeing time, and pH of the silk fabrics dyed with Rhus verniciflua extracts were $90^{\circ}C$, 100min, and in the nylon fabrics were $90^{\circ}C$, 45min. It were colored(munsell value) 6.4Y 7.5/4.1 in the silk fabrics and colored 4.3Y 6.6/5.9 in the nylon fabrics dyed with Rhus verniciflua extracts. Washing fastness and dry-cleaning fastness in the silk and nylon fabrics dyed with mordanting agent improved in $4{\sim}5$ grade. UV-A test showed that nylon fabrics a high rate of 92% with Rhus verniciflua extracts.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.2
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• pp.127-137
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• 2012

This study focuses on the optimal washing conditions for dry cleaning recommended fabrics to minimize dimensional changes using wet cleaning. We suggest water-based alternatives to a perchloroethylene based cleaning process. Wool and rayon fabrics were laundered under various washing conditions and then air-dried for 24hrs. All specimens were extended after spinning and shrunk after drying. This is probably because the fibers were swollen and extended by wetting. The wool fabrics were shown to be acutely influenced by washing temperature and mechanical force. The optimal washing conditions for wool fabric to minimize the dimensional change implied a normal washing temperature and minimized mechanical force. For rayon specimens, dimensional change by a hand wash showed a remarkable decrease compared with a machine wash. Rayon fabric seemed to be influenced by the quantity of water contained in the fabric after spinning and washing time. Therefore, the desirable washing conditions for rayon fabric are to reduce the time required for washing and to increase the spin speed.

• Journal of the Korean Society for Railway
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• v.20 no.3
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• pp.365-373
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• 2017

This study proposes a newly developed dry washing method for removing pollutants such as total petroleum hydrocarbon (TPH) and oxidized iron from the surface of ballast gravel. A batch-type dry washing method showed a good performance in a previous study. In this study, a continuous-type dry washing system, instead of a batch-type system, was prepared to improve the efficiency of the system. A drier and a separator were also applied to this system as pre-treatment process, and the performance of this system was evaluated. In this experiment, blasting media was blasted on the polluted gravels through 12 nozzles by a pressure of $5-6kg/cm^2$ for 20-30 mins to remove TPH and oxidized iron. It was found to be possible to remove 80-90% of TPH and oxidized iron by using this system. Several ways to improve the performance were suggested in this study.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1849-1852
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• 2005

An automatic cap-washing machine is developed for rinse and dry of synthetic resin cap which is used in spring water bottle. This machine should be achieved all processes washing and drying, array, transfer automatically. A cap is washed by an ozonized water and pure water first. Next, a cap is dried by a hot wind drying equipment. In this paper, structural and modal analysis for the cap-washing machine is carried out to check the design criterion of the machine. The analysis is carried out by FEM simulation using the commercial software, CATIA V5. And a fictitious mass properties was used for the analysis of the machine. Finally, the machine performance is shown to be satisfactory.

• Journal of the Korean Society of Costume
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• v.65 no.7
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• pp.47-59
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• 2015

This paper studies the conservation treatment of Lady Shim's costume, which was excavated in Jecheon Province in 2012. There were the significant problems, which were encountered in the treatment of the costume ; First the Jeogoris were transformed during the excavation, Second fibers were seriously deteriorated, Third most of the fabrics such as Chusa were readily deformed. To overcome these problems and to secure stability in the conservation treatment, we decided to alternate between two different washing methods ; dry cleaning by n-hexane and wet cleaning by water. The costume shape was recovered by steaming and by swelling with Hanji(Korean traditional paper). The combined cleaning method proved to be relatively efficient and stable. In addition, the shape of Chusa was well preserved by dry cleaning.(using n-hexane also solved the problem of bad smell after washing with organic solvents.) The effects of the conservation treatment on the excavated costumes could be seen in the change of Lab color difference. Washing made the distribution of Lab color difference narrower, which may suggest that the impurities on the fiber was removed by washing. In addition, the value of L was greater than a-value and b-value after the treatment. This result indicates that the change of value represents the change of color difference by cleaning.

• Journal of Soil and Groundwater Environment
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• v.9 no.1
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• pp.104-111
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• 2004

Several tests were conducted to optimize design parameters of soil washing technique for arsenic contaminated tailings and soils. Arsenic contaminated tailings and soils have been sampled from the N nine, Kwangwondo and the K mine, Kyungsangbukdo, respectively. According to the result of sequential extraction procedure, total arsenic concentrations were 21,028 $\pm$ 190, 443$\pm$7, and 37$\pm$3 mg/kg, for mine tailings, dry field, and river sedimentary soil, respectively. The subtotal of weakly bonded and easily releasable arsenic concentrations which were 2,284$\pm$100 (10.9%), 151$\pm$5 (34.0%), 15$\pm$3 (39.5%)mg/kg for mine tailings, dry field, and river sedimentary soil, respectively. Kinetics of arsenic extraction using NaOH showed that arsenic was extracted more than 90% after 6 hours for all samples. The optimized concentration of NaOH were 200 mM for all samples while the optimized dilution ratio were different to have 1:10 (mine tailings) and 1:5 (dry field, river sedimentary soil), respectively. Results of sequential soil washing tests using NaOH showed that arsenic concentrations obtained by Korean Standard Test Procedure were decreased to meet the regulation for both river sedimentary soil and dry field while they were not decreased largely for mine tailings, even though NaOH had much higher efficiencies of arsenic extraction than other extractants.