• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.2
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• pp.143-148
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• 2011

Corrosion at the top of a distillation column is a common problem in refineries and chemical plants. In particular, severe damage has been inflicted in refineries by corrosive materials such as hydrogen sulfide and chlorine. Therefore, the mechanism of the corrosion occurring at the top of a distillation column has been analyzed, and a model for forecasting the corrosion rate has been developed. Four major materials were selected for modeling: $H_2S$, $CO_2$, $H^+$ and $Cl^-$. These were selected by taking into consideration their effect on the corrosion rate. Studies on the transport phenomenon and reaction engineering for this model were carried out, and the reliability of the model was verified on the basis of the data measured at a real refinery.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.106-106
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• 2004

보일러에서 연소된 후 배출된 가스는 탈황목적으로 설치된 흡수탑 내에 유입되어 Slurry Spray Nozzle에서 분사된 Limestone Slurry에 의해 배기가스중의 SO$_2$를 흡수한 다음 반응조로 떨어지게 되지만 분사된 액적의 일부는 배기가스의 압력에 의하여 같은 유동 방향으로 미세한 Mist의 형태로 배기가스와 함께 흡수탑의 Outlet Duct를 통해 빠져나간다. 이 Mist(액적크기 40 $\mu\textrm{m}$이하)에는 고형 성분이 함유되어 있는데 보통 Chloride농도가 높아 탈황설비 후단 (duct, GGH, Stack)에 plugging, 부식 등의 문제를 유발하므로 Spray Header상부에서 Mist Eliminator를 설치하여 Mist를 제거하도록 한다.(중략)

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.236-236
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• 2004

삼중수소수 오염처리의 선행공정으로 적합한 전기분해-촉매교환 결합공정(CECE process)은 수소동위원소 산화물의 수소화 전환을 위한 전해셀과 다단 액상촉매 교환탑으로 이루어진 탈삼중수소 공정이다(그림 1). 촉매탑은 수소 흐름에 수증기를 동반하도록 하는 친수층과 수증기-수소간의 수소동위원소 교환반응을 유도하는 촉매층으로 구분되며, 탑 상부에는 수소의 산화 반응기 그리고 하부에는 물의 수소화 전해셀로 구성되어 있다(그림 2).(중략)

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.2
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• pp.1032-1037
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• 2011

In this study, simulation and optimization works for a demethanizer column have been performed to obtain ethane and heavier products from a pretreated natural gas stream. Pretreated natural gas feed stream was partially condensed after being precooled by exchanging heat with demethanizer top vapor stream and by using an external refrigeration cycle with a propane refrigerant. Vapor stream was cooled further and partially condensed through a turbo-expander. The power generated from the expansion of turbo-expander was delivered to the compressor for the residue gas compression. Liquid stream was cooled by Joule-Thomson expansion valve and was fed to the middle section of the demethanizer. Recovery percent of ethane for feed natural was set to 80% and methane to ethane molar ratio was fixed as 0.0119. On the other hand, some of the cold heat could be recovered by splitting the feed stream and by exchanging heat with side reboiler in order to reduce the heat duty in the propane refrigeration cycle.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.3
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• pp.1473-1478
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• 2011

In this study, simulation and optimization works for a demethanizer column have been performed to obtain ethane and heavier products from a pretreated natural gas stream. Pretreated natural gas feed stream is partially condensed after being precooled by exchanging heat with demethanizer top vapor stream and by using an external refrigeration cycle with a propane refrigerant. Vapor stream is furtherly cooled and partially condensed through a turbo-expander and the power generated from the expansion of turbo-expander was delivered to the compressor for the residue gas compression. Liquid stream is being cooled by Joule-Thomson expansion valve and is fed to the middle section of the demethanizer. Ethane recovery percent for feed natural gas was set to 75% and methane to ethane molar ratio was fixed as 0.015. Propane refrigeration heat duty was reduced by splitting the feed stream and to exchange heat with side reboiler.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3774-3778
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• 2012

A dynamic simulation of a fully thermally coupled distillation is conducted for the design of a possible operation scheme, and its performance is examined with an example process of reformate fractionation process. The outcome of the dynamic simulation indicates that the column can be operated by using a $3{\times}3$ control structure. The structure consists of three controlled variables of the compositions of overhead, side products and bottom and three manipulated variables of the flow rate of reflux, liquid split ratio between a main column and a prefractionator and steam.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.05a
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• pp.185-186
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• 2018

에어보트(Air boat)는, 판옥선처럼 선체 밑바닥이 편평한 형태로 되어있어 물위는 물론 일반 선박이 갈 수 없는 얕은 수면, 개펄, 빙상, 늪지수풀 위를 달릴 수 있는 모터보트의 한 종류이다. 선체상부 뒤쪽에 장착된 로터의 회전에 의한 풍력으로 추진되며, 로터 바로 뒤에 방향키가 있다. 선체 재질로는 스틸, FRP가 주로 사용되고 있으며 최근 알루미늄, 탄소섬유의 적용이 늘어나고 있다. 수상크루징, 낚시, 스쿠버 등에 활용되며, 선저의 독특한 형상으로 인해 군사용, 인명구조용, 수산물수송용 등으로도 사용된다. 이 연구에서는 12인승 비미니탑 에어보트를 설계, 제작하고 해상 시운전을 실시하였다. 또한 소음저감을 위해 머플러를 설계 제작하고, 35노트에서 75~78dB 수준으로 성능을 검증하였다.

• Korean Chemical Engineering Research
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• v.47 no.3
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• pp.327-331
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• 2009

A thermally coupled distillation system is constructed using two columns used in a conventional two column system, and its operability is examined by investigating the dynamic behavior. For the control of three product specifications, the step response test is performed and a $3{\times}3$ control structure using flow rates of overhead and side products and vapor boilup is suggested. The performance of the proposed control system indicates that the specification control of bottom product is the most difficult but the operation of the proposed system is available.

• Journal of Radiation Protection and Research
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• v.33 no.1
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• pp.35-40
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• 2008

A distillation tower is one of the important facilities which separates and refines a crude oil stream according to certain boiling points. Its operation efficiency can affect the productivity of a refinery substantially. The objective of this study is to elucidate some operational information on the internal conditions of a distillation tower from a measurement of density profile by using a sealed gamma-ray source and a radiation detector. Gamma radiation counts were measured by a BGO detector positioned diametrically outside the tower-wall, opposite to the gamma source(Co-60) as the detector and the source were lowered concurrently. From the results, structural abnormality of the trays was not found inside the tower. Considering the flow distribution patterns, however, a vapor phase was dominantly formed at the upper part of the tower and a liquid phase at the lower part. From the gamma scanning of the distillation tower, it is anticipated that the gamma absorption technique can be used as an important tool for confirming the structural soundness of trays and investigating flow distribution in refinery facilities.

• Clean Technology
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• v.22 no.4
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• pp.241-249
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• 2016

In this study, comparative work has been performed between two-columns and three-columns configurations for an extractive distillation process to produce highly purified ethanol with not less than 99.7 wt% using dimethyl sulfoxide (DMSO) and ethylene glycol (EG) as extracting agents. Optimal ethanol concentration at a concentrator top stream which minimized the total reboiler heat duties was determined for a three-columns configuration for two different solvents. For the thermodynamic model, NRTL liquid activity coefficient model was used and PRO/II with PROVISION 9.4 at Schneider electric company was utilized. DMSO was proved to be a better solvent than EG and three-columns configuration is better than two- columns configuration in the total utility consumptions since some of the liquid water contained in the feed stream was removed at a concentrator bottom liquid stream.