• 공업화학
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• 제32권6호
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• pp.659-663
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• 2021

반도체 제조공정에서 발생하는 미세먼지와 질소산화물 동시처리를 위하여 오존산화, 습식중화 및 습식전기집진 기술들을 직접화한 10 CMM급 복합오염물질 제거시스템을 개발하였으며, NOx 제거효율 증대를 위한 공정변수 제어 및 최적화를 진행하였다. 특히, 전원공급장치를 포함한 습식전기집진장치 핵심부품 안정성 평가를 위해 30일 동안의 장기운전도 병행하였다. 오존산화 기반 DeNOx 공정에서 가장 중요한 운전변수인 O₃/NO 비율은 1.5 부근에서 최적화하였으며, 습식중화 공정의 운전변수를 최적화하여 중화반응에 의한 제거효율 기여도를 확인하였다.

• 유기물자원화
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• 제27권2호
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• pp.51-56
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• 2019

황화수소는 매립가스와 바이오가스 사용 전에 제거해야 하는 유해한 불순물이다. 본 연구에서는 공기 산화를 활용한 황화수소 저감 방법을 연구하였다. C시 매립장에서 발생하는 매립가스의 유량 조절이 가능한 실규모 황화수소 저감 장치를 운전하였다. 실험 결과, 세정액 내 용존 철 농도는 황화물 산화 효율에 유의한 영향을 미쳤다. 매립지 발생 침출수 내 철 성분은 매립가스 내 황화수소 제거를 위한 용도로 철킬레이트와 혼용할 수 있었다. 철 농도가 90 mM 이상인 경우 9 초 이내의 접촉 시간에서 83 % 이상의 $H_2S$가 제거되었다. 따라서 촉매 산화 흡착법은 매립가스 및 바이오가스 정제를 위한 용도로서 충분히 가치가 있는 것으로 판단되었다.

• Nuclear Engineering and Technology
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• 제55권1호
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• pp.169-179
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• 2023

Filtered containment system is a passive safety system that controls the over-pressurization of containment in case of a design-based accidents by venting high pressure gaseous mixture, consisting of air, steam and radioactive particulate and gases like iodine, via a scrubbing system. An indigenous lab scale facility was developed for research on iodine removal by venturi scrubber by simulating the accidental scenario. A mixture of 0.2 % sodium thiosulphate and 0.5 % sodium hydroxide, was used in scrubbing column. A modified mathematical model was presented for iodine removal in venturi scrubber. Improvement in model was made by addition of important parameters like jet penetration length, bubble rise velocity and gas holdup which were not considered previously. Experiments were performed by varying hydrodynamic parameters like liquid level height and gas flow rates to see their effect on removal efficiency of iodine. Gas holdup was also measured for various liquid level heights and gas flowrates. Removal efficiency increased with increase in liquid level height and gas flowrate up to an optimum point beyond that efficiency was decreased. Experimental results of removal efficiency were compared with the predicted results, and they were found to be in good agreement. Maximum removal efficiency of 99.8% was obtained.

• Nuclear Engineering and Technology
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• 제35권5호
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• pp.482-496
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• 2003

effectiveness of the PAM graphite-electrode technology for the treatment of many types of low-level radioactive waste including : combustible material, solidified resins in cement, inorganic materials, steel, glass, and solidified boric acid cement. The objectives of PAM-200 evaluation were to verify that 1) the facility meets air emission regulations, 2) the facility can be safely operated when processing hazardous and radioactive materials and 3) satisfactory final waste forms can be produced. Results, derived from KAERI's(Korea Atomic Energy Research Institute) analyses for samples of vitrified product, scrubbing solution and offgas collected during test period, show that PAM-200 can treat radioactive wastes as well as hazardous wastes with toxic constituents and radionuclides contained in the offgas exiting from the stack to the environment controlled to be far lower than the limit regulated by air conservation law and atomic law.

• 한국환경과학회지
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• 제9권5호
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• pp.389-392
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• 2000

In this study a packed tower was selected for the treatment apparatus of $NH_3$ gas produced in industry. Formerly latticework packing has been used in preventive facility of treatment of $NH_3$ gas. However recently metallic Ralu-Pack 250YC. structured packing is usually being used in petrochemical production plant. This study is for the application the packing to the $NH_3$ gas treatment in wet scrubbing process. In Air/water system hydraulic pressure drop dependent of specific liquid load and gas capacity factor was continuous and parallel from graph. The tower height can be determuined by the number of transfer unit and the height of transfer unit influenced on liquid distribution.

• 전기학회논문지
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• 제60권5호
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• pp.1036-1042
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• 2011

This paper presents an algorithm that conducts automatic memory scrubbing operated by dedicated hardwares. The proposed algorithm is designed so that it can scrub entire memory in a given scrub period, while minimally affecting the execution of flight softwares. The scrub controller is constructed in a form of state machines, which have two execution modes - normal mode and burst mode. The deadline event generator and period tick generator are designed in a separate way to support the behavior of the scrub controller. The proposed controller is implemented in VHDL code to validate its applicability. A simple version of the controller is also applied to mass memory modules used in STSAT-3.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2004년도 학술대회지
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• pp.85-106
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• 2004

Styrene as volatile organic compounds(VOC) has come under strict regulatory control as they cause serious health and environmental problems. Biofiltration offers a number of economical and environmental advantages over conventional technologies, such as incineration, catalytic adsorption, and chemical scrubbing. In this presentation, recent progresses on the development of lab-scale biofilter for the treatment of gas-phase styrene are reviewed, The potentials of commercialization of biofilter systems are also discussed.

• 한국환경과학회지
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• 제18권2호
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• pp.187-195
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• 2009

This study was investigated to control the corrosion and scale at the cooling water system in steel works. Laboratory and field tests were performed for the indirect cooling water system of plate mill. Throughout the experiment, various factors such as leakage of pipes, heating rate and capacity, and the reaction between existing and substitute inhibitors were carefully monitored. The results showed that the harmful effect of high temperature could be minimized, and satisfactory corrosion/scale controls were effectively achieved using inhibitor, even at the increased temperature of $80^{\circ}C$. The batch and field tests in the gas scrubbing cooling water system of blast furnace and cooling water system of corex plant indicated that the new inhibitor was more effective for the prevention of corrosion and scale than the existing one.

• 한국의류학회지
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• 제32권3호
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• pp.505-516
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• 2008

Image which appears in fashion illustration on the late twentieth century is not the representative image as an equivalence to the real fashion styles but the virtual image which bears no relation to any reality. The purpose of this study is review the concept of virtuality and analyze in which way virtual image is expressed in fashion illustrations on the background of Jean Baudrillard's simulacre theory. In post-modem paintings the expression methods of image-virtualization were image mixing through photo-image appropriation, image overlapping, and the icons inserted unreasonably, the focus-out effect through scrubbing and the over-painting on the photograph. Image-virtualization in fashion illustration was expressed through image mixing and expression of image uncertainty. Image mixing was made by photo-image appropriation, image overlapping, connection of heterogeneous images and using interface image, and uncertain image was expressed through the expression of visual ambiguity and virtual movement.

• 한국대기환경학회지
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• 제8권4호
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• pp.262-268
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• 1992

The trend of international concerns on environmental conservation and domestic demand of ambient air quality improvement, specially on sulfur dioxide level has resulted in the establishment of mid-term strategy of environmental improvement and stepwise strengthening of emission regulations in this decade in Korea. Development of flue gas desulfurization(FGD) process is becoming an essential task to be accomplished especially for the power plants and large industrial facilities. This study is an initial stage researc focusing on the mass transfer principles in wet type FGD process and the effects of operating variables of a jet bubbling scrubber utilizing limestone slurry on sulfur dioxide removal efficiency. Experimental results showed this type of scrubbing system has some advantages in terms of mass transfer mechanism and removal efficiency. More rigorous research is needed for the reaction system and the comparison with existing FGD processess for the possible development of a process which is compatative in view of installation cost and treatment of by-products.