• Journal of the Korean Society of Safety
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• v.35 no.6
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• pp.85-92
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• 2020

Wet Scrubber reacts the incoming pollutant gas with cleaning water (water + absorbent) to absorb pollutants and release the clean air to the atmosphere. Wet scrubbers and packed tower scrubbers using this principle are widely used in businesses that emit acid gases. In particular, in the etching process using hydrochloric acid (HCl), alkaline washing water (NaOH) having a pH of about 8 to 11 is used to absorb a large amount of acid gas. However, These salts are attached to the injection nozzle (nozzle), filling material (packing), and the demister (Demister), causing air pollution, human damage, and inoperability due to clogging and acid gas discharge. Therefore, In this study, an improvement plan was proposed to manage the washing water with pH 3~4 acidic washing water. The test method takes samples from the Wet Scrubber flue measurement laboratory twice a month for 1 year. Hydrogen chloride (HCl) concentration (ppm) was measured, and nozzle clogging and scale conditions were measured, compared, and analyzed through a differential pressure gauge and a pressure gauge. As a result of the check, it was visually confirmed that the scale was reduced to 50% or less in the spray nozzle, filler, and demister. In addition, the emission limit of hydrogen chloride in accordance with the Enforcement Regulation of the Air Quality Conservation Act [Annex 8] met 3 ppm or less. Therefore, even if the washing water is operated in an acidic pH range of 3 to 4, it is expected to reduce air pollution and human damage due to clogging of internal parts, and it is expected to reduce maintenance costs such as regular cleaning or replacement of parts.

• Journal of Environmental Science International
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• v.21 no.8
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• pp.977-988
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• 2012

This study analyzed the characteristics of stormwater runoff by rainfall type in orchard areas and transportation areas for 2 years(2010~2011year). Effluents were monitored to calculate the Event Mean Concentrations(EMCs) and runoff loads of each pollutant. The pollutant EMCs by volume of stormwater runoff showed the ranges of BOD 0.9~13.6 mg/L, COD 13.7~45.2 mg/L, SS 4.1~236.4 mg/L, T-N 2.123~21.111 mg/L, T-P 0.495~2.214 mg/L in the orchard areas, and was calculated as BOD 2.3~22.5mg/L, COD 4.4~91.1 mg/L, SS 4.3~138.3 mg/L, T-N 0.700~13.500 mg/L, T-P 0.082~1.345 mg/L in the transportation areas. The correlation coefficient of determination in the orchard area was investigated in the order of Total Rainfall(0.81) > Total Runoff(0.76) > Rainfall Intensity(0.56) > Rainfall Duration(0.46) > Antecedent Dry Days(0.27). Also, in the case of the transportation area was investigated in the order of Total Rainfall (0.55) > Total Runoff(0.54) > Rainfall Intensity(0.53) > Rainfall Duration(0.24) > Antecedent Dry Days(0.14). As the result, comparing valuables relating to runoff of non-pollutant source between orchard areas and transportation areas, orchard area($R^2{\geq}0.5$ : X3, X4, X5) was investigated to have more influence of diverse independent valuables compared to the transportation area($R^2{\geq}0.5$ : X3, X4) and the difference of discharge influence factor by the land characteristics appeared apparently.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.2
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• pp.96-101
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• 2021

Developing effective and earth-abundant electrocatalyst for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is critical for the commercialization of a water splitting system. In particular, the overpotential of the OER is relatively higher than the HER, and thus, it is considered that one of the important methods to enhance the performance of the electrocatalyst is to reduce the overpotential of the OER. We report effects of incorporation of metalloid into Ni(OH)2 microcrystal on electrocatalytic activities. In this study, Te incorporated Ni(OH)2 (��Te-Ni(OH)2) were grown on three-dimensional porous NF by a facile solvothermal method with �� = 1, 3 and 5. Homogeneous microplate structure on the NF was clearly observed for the Ni(OH)2/NF and ��Te-Ni(OH)2/NF samples. However, irregular and collapsed nanostructures were found on the surface of nickel foam when Te precursor ratio is (��) over 3. Electrocatalytic OER properties were analysed by Linear sweep voltammetry (LSV) and Electrochemical impedance spectroscopy (EIS). The amount of Te incorporation used in the electrocatalytic reaction was found to play a crucial role in improving catalytic activity. The optimum Te amount (��) introduced into the Ni(OH)2/NF was discussed with respect to their OER performance.

• The Korean Journal of Food And Nutrition
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• v.36 no.1
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• pp.42-49
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• 2023

To enhance the efficacy of Abeliophyllum distichum leaves, extracts were prepared using different solvents for hydrolytic enzyme-treated Abeliophyllum distichum leaves. Physicochemical quality and antioxidant activity were measured. Soluble solids, reducing sugar, ascorbic acid, flavonoids, and polyphenols contents showed the lowest values in the control without enzyme treatment. However, they showed high contents in ethanol extract. In the case of enzyme treatment, their values were higher than those of the control. In particular, verbascoside content increased about 220 times more than that of the control group when treated with enzymes and extracted with 50% ethanol. pH was lowered upon enzymatic treatment. Regarding DPPH radical scavenging activity, for enzyme-free, 25% ethanol extract showed the highest activity among extracts with different solvents. For cellulase and pectinase-treated leaves, water extract showed the highest DPPH radical scavenging activity among extracts with different solvents. For leaves treated with enzyme combination, 50% ethanol extract showed the highest DPPH radical scavenging activity among extracts with different solvents. Regarding ABTS radical scavenging activity, it was generally higher in the 50% ethanol extract than in the water extract and 25% ethanol extract. In particular, verbascoside content was increased when the extract was prepared by co-treatment with enzymes and 50% ethanol.

• Proceedings of KOSOMES biannual meeting
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• 2005.05a
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• pp.175-177
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• 2005

본 연구는 도서지방에 식수를 안정적으로 공급하기 위하여 도서별 특성에 적합한 최적의 상수원 방안을 마련하는데 목적이 있다. 특히 도서지역은 지형적인 특정상 상수원 확보를 위한 저수지 건설의 적지가 드물고 이상 가뭄과 환경오염으로 물 부족 현상이 심화되고 있으므로 도서지방의 안정적인 식수 공급 방안 수립은 시급한 실정이다.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.28 no.4
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• pp.182-186
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• 2020

As all flight training institutions in Korea were approved by the Ministry of Land, Infrastructure and Transport (MOLIT) as aviation training organizations (ATO), safety management based on the Aviation Safety Management System (SMS) became mandatory. However, even though safety management using SMS has become mandatory, the performance of aviation safety voluntary report, which is the core of the system, remains low compared to other countries. The current address of SMS, a ATO, is like a watermill without water. The present study is to find out why voluntary aviation safety reports, which is equivalent to water from waterwheel, is underperforming and to suggest ways to revitalize it.

• Ocean and Polar Research
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• v.40 no.3
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• pp.161-167
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• 2018

We examined the effect of salinity and water temperature on hatching and survival rates of fertilized eggs of hybrid grouper (Epinephelus fuscoguttatus ♀ ${\times}$ E. lanceolatus ♂) at different developmental stages, determining optimal conditions for their long-distance transportation. Deformities and hatching rates of fertilized grouper eggs were observed at salinities of 24, 27, 30, 33, 36, and 39 psu. The optimal salinity was determined to be 36 psu, with a survival rate of $70.0{\pm}2.0%$. Transportation experiments at 36 psu were conducted at water temperatures of 21, 24, 27, and $30^{\circ}C$, different developmental stages such as morula, 5-myomere, and tail beating for hatching and survival rates. The optimal water temperature and developmental stage for transporatation were $30^{\circ}C$ and tail beating stage and those hatching rates were $50.6{\pm}1.9%$ and $86.3{\pm}1.3%$, respectively. At $21^{\circ}C$, the survival rate by transportation water temperature was highest ($73.1{\pm}10.6%$), but the hatching rate ($17.1{\pm}3.1%$) was lowest. Therefore, the hybrid grouper fertilized eggs (E. fuscoguttatus ♀ ${\times}$ E. lanceolatus ♂) can be most efficiently produced under long-distance transportation conditions during the tail beating stage and at a water temperature of $30^{\circ}C$.

• Journal of Korean Society of Water and Wastewater
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• v.10 no.3
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• pp.115-132
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• 1996

The present problems concerning the control of generation, storage, collection, transfer and transport, processing and disposal of the municipal waste are serious. And the transportation of the municipal waste is recently a important part of solid waste treatment and disposal. The waste pneumatic transportation system is expected to be an effective method for use in solving that problems. In this study, pneumatic transportation system was applied to 2,000-5,000 households of public/group housing for economic and technical analysis on the basis of data for working and operation. The proper equipment must be selected through economic and technical analysis for generation and properties of waste because the equipment in facilities of system is various. And the efficient operation method should be studied on the basis of information on the record of oeration. As the wet food waste clogs the pipeline, it is necessary to examine under the actual condition. The maximum unit waste generation rate based on the assumption that each household is comprised of 3.20 people is determined $2,340g/household{\cdot}day$, and it is included the 50% increase of seasonal and daily change.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.7
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• pp.341-349
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• 2017

Formation and transportation of $CO_2$-hydrate slurry was conducted by circulating saturated water with $CO_2$ through a double-tube type heat exchanger which was cooled down by brine. The inner diameter and circulation length of the heat exchanger were 1 inch and 20 m, respectively. Water in tank was supersaturated by injected $CO_2$ and the operation pressure was maintained at 3,000 to 4,000 kPa with fluid-temperature of less than $9^{\circ}C$. $CO_2$ hydrate mass fraction was calculated based on density of $CO_2$-hydrate slurry mixture. Results showed that the $CO_2$-hydrate slurry could be circulated without blockage for 1 hr. Circulation status of the $CO_2$-hydrate slurry was also visualized.

• Journal of Climate Change Research
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• v.5 no.4
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• pp.291-300
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• 2014

In this study, we investigated the activity data and basic data of the surface of the water within the ship to be operated by lakes and rivers inland. In this study previously, there was no survey activity data of Ferry and Cruise ship in Korea. In order to ensure the basic data and development of measures to reduce efficiently by local governments, these studies should be performed. Therefore, in the present study was survey the activity data such as cruising time and engine load factor and the specifications of the vessels. As a result, by analyzing the cruising pattern according to the area and the purpose of the cruise, to calculate the emissions of greenhouse gases.