• Membrane Journal
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• v.1 no.1
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• pp.78-95
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• 1991

Water factory 21(WF 2) in Orange County California, is a advanced wastewater treatment(AWT) plant designed to reclaim biologically treated munidpal wastewater for injection into a seawater barrier system. Processes included are lime treatment air stripping, filtration, activated carbon adsorption, reverse osmosis(RO), and chlorination. The effectiveness of each treatment process is presented including pretreatment, RO dimineralization. The data collected show that the processes, including RO, used at WF-21 are capable of producing a very high quality water on a reliable basis. Treatment reduced all contaminants, to levels below national primary drinldng water regulation maximum contaminant levels. It was found that lime clarified secondary effluent can be used as feedwater to a RO dimineralizer. Experiments with new low pressure membrane(250psi) show great potential for reducing RO cost.

• The Journal of the Acoustical Society of Korea
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• v.19 no.1
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• pp.40-47
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• 2000

To obtain the acoustic properties of dispersive polyurethane with high attenuation, through transmission method was applied by ultrasonic. In through transmission method, the sound velocity and attenuation coefficient of specimen were obtained by using Sachse's method which can be applied to small size specimen. But there is a problem when the reference signal is selected, so the result is not precise. The more precise acoustic properties of polyurethane was obtained when two specimens with different thickness were used. To predict the acoustic properties of low frequency range, the acoustic properties extended to the low frequency range were calculated by Kramers - Kronig relation. As a result, we studied on the relation between the sound velocity and the attenuation coefficient with frequency.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.93-93
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• 2011

고진공 펌프 국산화의 일환으로 터보분자 펌프와 크라이오 펌프 개발이 진행 중이다. 크라이오 펌프 개발은 기계연구원, 우성진공(주), 국민대학교가 연합해서 수행하고 있다. 올해 9월말에 끝나는 1단계 마지막 3차 년도에는 두 고진공 펌프 모두 시제품을 완성하고 성능을 입증해야 한다. 이를 위해 고진공 펌프 개발과 별도로 진공 펌프 종합특성평가 시스템 개발도 표준과학연구원 주도로 진행되고 있는데 크라이오 펌프 평가 시스템은 원자력연구원이 담당하고 있다. 완성된 크라이오 펌프 성능평가 장치는 상온 기준 5${\times}$10-11 mbar의 기저압력을 보이고 있어서 초고진공 영역에서 크라이오 펌프 운전성능을 평가할 수 있는 준비를 마쳤다. 현재 크라이오 펌프 냉동기는 전반적으로 목표 설계치에 근접한 냉각성능을 나타내고 있는데 예를 들면 2차 냉각단 냉각능력이 10 K, 10 W로 대형 크라이오 펌프를 제작하기에도 충분하다. 활성탄 어레이도 여러 모델들을 자작하여 배기성능을 시험해 보았으므로, 최종적으로 3,600 L/s 급에 적합한 어레이를 만들고 이를 개발된 냉동기에 얹고 열차폐와 몸통을 씌워 펌프로서의 운전성능을 평가하는 일이 남아있다. 시제품은 상용품과 달리 기기가 차지하는 공간이 크고 부대설비가 복잡해서 운전성능 평가 장치에 부착해서 실험하기 어려울 수도 있으므로 기계연구원 현장에서 진공 게이지와 기체도입구만 부착한 마구리 플랜지를 펌프 흡기구 위에 달고 간이로 배기속도를 측정하는 것도 고려하고 있다. 이 경우는 표준용기를 사용할 때보다 배기속도가 과대평가되므로 이를 보정해 주는 방안을 마련해 놓아야 한다.

• Fire Science and Engineering
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• v.25 no.6
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• pp.27-31
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• 2011

In this study, combustion toxicity evaluation for building interior materials and study for toxicity as using FT-IR analysis. this experiment for the calculation of toxicity index, it using a cone calorimeter model in KS F ISO/TR 9122-4 as a fire model. It is following ISO 19702 procedure for assessing fire toxic gas using FT-IR. This experiment used calculation method for toxicity index (FED) among the international standards. $LC_{50}$ is a concentration that it can cause death to 50 % of experimental animal in 30 minutes - exposure gas test. comparison with the three kinds of toxicity fire gas of construction materials using toxicity index.

• Prospectives of Industrial Chemistry
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• v.23 no.4
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• pp.1-12
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• 2020

최근 실내 공기질(IAQ; indoor air quality)을 악화시키는 물질 중 하나인 이산화탄소 저감 연구가 다수 진행되고 있다. 현재 이산화탄소를 저감하는 방법에는 흡착법, 흡수법, 막분리법 등이 있다. 그 중 흡수법은 액체 상태의 흡수제를 분사하는 공정 특성상 실내에 적용하기 어렵고 2차 오염물 또는 폐수가 발생할 수 있다. 또한, 막분리법은 이산화탄소 분리를 위한 응집 및 침전과 같은 전처리 과정이 필요하므로 실내 이산화탄소 저감에 적합하지 않다. 반면, 흡착법은 비교적 저렴하고 운영이 간단하여 적용 사례가 증가하였으며, 유동 인구가 많고 환기가 어려운 지하철, 버스 등의 대중교통 차량 내부 및 교실, 사무실, 공공시설에서 배출되는 실내 이산화탄소를 제어할 수 있다는 장점이 있어 가장 적합한 해결책으로 알려져 있다. 흡착 공정에 사용되는 대표적인 흡착제 종류에는 활성탄, 제올라이트, 알루미나 등이 있으며, 이 흡착제들을 개질 및 성형하여 흡착제의 성능 및 기계적 강도를 증진시키는 고도화 연구가 활발히 수행되고 있다. 이처럼 적용 대상 내 설치 및 교체가 용이하도록 하는 흡착제 제조 기술 개발이 필요한 실정이며, 흡착제를 상용화 수준까지 발전시킴으로써 강화된 실내 공기질 규제 기준에 대한 대응 및 삶의 질 향상이 기대된다.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2022.10a
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• pp.381-382
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• 2022

국내에서 1980년대까지 연탄을 에너지로 많이 사용하면서 일산화탄소 중독이 빈번하여 고압산소치료가 활용되다가 이후 연탄 사용의 감소로 고압산소치료기가 대부분 활용되지 못하고 폐기되는 경우도 많았다. 이후 세월호 사고에서의 잠수사들에 대한 고압산소치료 적용, 가스누출이나 번개탄을 활용한 자살시도가 빈번해지며 고압산소치료기를 보유하고 있는 기관이 부족해 적절한 치료를 제 때 받지 못하여 고압산소치료기의 필요성이 되두되었다. 국내에서는 2021년 기준으로 한해 36,266 건의 화재가 발생하고 2020년에 365명이 화재로 사망하며, 화재로 인한 손상은 1,917건이었는데. 화재 시 여러 유독가스를 흡입하게 되고, 이에 따라 고압산소치료가 필수적으로 진행되어야 한다. 유해화학물질 사고, 대규모 오염, 다양한 교통수단에서의 대형 사고, 건축물 붕괴 사고 및 대규모 지진, 화산폭발 같은 자연재해 시에도 가스 중독이 발생하며, 이는 고압산소치료가 필요하게 된다. 따라서 다양한 종류의 재난에서 발생하는 유독가스 피해자에게 고압산소치료는 필수적이나 본 연구에 의하면 국내에는 고압산소치료챔버의 숫자와 동시에 고압산소치료로 수용할 수 있는 환자수에도 한계가 있고 그 분포의 불균형도 존재하고 있어 재난 시 인명 피해 감소의 기반 장비, 시설로서 고압산소챔버의 균형있는 확산, 적용이 시급한 실정이다. 다행히 최근 전국적으로 고압산소챔버가 증가하는 추세에 있어 그 현황과 배치 상황을 조사하여 이를 통하여 고압산소챔버가 필요한 유독가스 발행 재난에 대비할 수 있는 역량이 증가하고 있다.

• Applied Biological Chemistry
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• v.44 no.2
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• pp.97-102
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• 2001

Cheju island depends on a hydrogeologically vulnerable aquifer system as its principle source of drinking water. Most of golf courses are located in the area which is important for the ground water recharge, and pesticides are applied to golf courses often at relatively high rates. Therefore, turf pesticides in golf course should be applied without adversely impacting ground water. In this experiment, downward movement of pesticides was monitored in model greens of golf course, where different adsorbents were layered in 3-cm thickness at 35-cm depth, and effect of the adsorption layer on the leaching loss of pesticides was investigated. Major leachings were observed in the periods of heavy rain and very limited leaching was observed under artificial irrigation. Fenitrothion and triadimefon, which have relatively short persistence and high adsorption coefficient, were found in the leachate in low concentrations only at the first rainfall event, around 20 days after the pesticide application. However, diniconazole, which has a relatively long half-life (97 days), was detected in the leachate during the whole period of experiment and concentration was much higher than those of the other pesticides. Maximum leachate concentrations were 1.9, 10.3, and 84.5 ${\mu}l^{-1}$ for fenitrothion, triadimefon, and diniconazole, respectively. Therefore, in golf course green which allows rapid water percolation and has extremely low adsorption capacity, persistence in soil could be more important factor in determination of leaching potential of pesticides. Total quantity of pesticides leached from the model green was <0.2% for fenitrothion and triadimefon and 1.8% for diniconazole. Adsorption layers significantly reduced pesticide leaching, and active carbon and Orpar were more effective than zeolite. In the model green having adsorption layer of active carbon or Orpar, leaching loss of pesticides was reduced below 0.01% of the initial application.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.4
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• pp.553-561
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• 2020

Water-soluble rubber asphalt-based waterproofing material, which is one of the waterproofing materials for building structures, is mainly used indoors (toilet, kitchen, balcony, etc.). In general, asphalt-based materials are used for non-exposed installation, rather than as exposed type as they do not deviate from their usual basic black pigmentation, and water-soluble rubber asphalt-based coating waterproofing materials are basically limited to indoors because of their low physical properties. Accordingly, in order to improve the tensile and elongation properties, a silane coupling agent, an inorganic filler, and a processor oil w ere added to improve the physical properties, and accordingly, the basic physical properties of the outdoor coating waterproofing material quality standard were analyzed. As a result, the water-soluble rubber asphalt coating waterproofing material compared with the exposure quality standard showed a result that exceeded the basic physical property quality standard of silicone rubber in all items under test evaluation, but the tensile strength and tear strength of the first class of urethane rubber were chloroprene. It was found that the performance compared to the quality standards of rubber-based tear strength was about 34.2% to about 40.8%.

• KSBB Journal
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• v.16 no.3
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• pp.286-289
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• 2001

A beterotrophic Pseudomonas putida B2 was used to treat of hydrogen sulfide containing gas. The experimental approach involved operating two indentical bench-scale biofilters with media consisting of a mixture of peatmoss, perlite and granular activated carbon(GAC). One column was seeded with Pseudomonas putida B2 and the other was left unseeded. The biofilter was operated for 16 days under EBRT for 20-40 sec, at a temperature of 25-30$^{\circ}C$ and a hydrogen sulfide concentration of 40-190 ppm. The biofilter inocculated with P.putida B2 exhibited high hydrogen sulfide removal efficiency, average of 95%, at a gydrogen sulfide concentration of 40-190 ppm (flow rate 3.6 L/min). However, at a shock loading of 190 ppm the biofiter showed a removal efficiency of 78.9% and the control only showed a removal efficiency of 31.6%. The critical load of this biofilter was 14.83 g/㎥hr, and the critical load of the control column was 4.93 g/㎥hr. These results suggest that P. putida B2 has the potential to be used as a $H_2S$ removal agent in a biofilter.

• Journal of Energy Engineering
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• v.18 no.3
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• pp.191-202
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• 2009

South Korea, ranks 10th largest emitter of carbon dioxide in the world, will probably be under the obligation to reduce GHG emission from 2013. It is very important to reduce the electrical energy consumption since 30% of GHG emission in South Korea is made during electricity generation. In this study, based on "the 1st national energy master plan", the GHG emission reduction potential and the feasibility of the scenario in the electricity generation have been analyzed using LEAP(Long-range Energy Alternative Planning system). The scenario of the mater plan contains the 41% expansion of nuclear power plant facilities and the 11% diffusion of renewable energy until 2030. In result, total $CO_2$ emission reduction rate is 28.8% in 2030. Also $CO_2$ emission of unit electricity generation of bituminous coal power plant is $0.85kgCO_2/kWh$ and its LNG power plant is $0.51kgCO_2/kWh$ in BAU scenario. Therefore when existing facilities is exchanged for nuclear or renewable energy power plant, substitute of bituminous power plant is more effective than LNG power.