• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.55-60
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• 2012

The energy conservation and exergy loss of a fully thermally coupled distillation commercialized as the divided wall column are compared with those of a conventional two-column system for ternary separation. The used example for the comparison is the benzene-toluene-m-xylene separation process widely used in a petrochemical plant. The design procedure of the fully thermally coupled distillation column is explained, and the energy requirement is compared using the HYSYS. When the same numbers of trays are utilized, the fully thermally coupled distillation column uses 28.2% less energy and 10.4% more exergy loss. The increase of the exergy loss is due to the additional mixing from the bidirectional inter-linking and the temperature elevation in the reboiler from the increased pressure at the bottom of the main column.

• ICROS
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• v.6 no.3
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• pp.54-61
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• 2000

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.21-27
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• 2018

FRN (Full range Naphtha) is distilled from crude oil in a Naphtha Splitter Unit and is separated into the Light Straight Naphtha, Heavy Naphtha, and kerosene according to the boiling point in sequence. This separation is conducted using a series of binary-like columns. In this separation method, the energy consumed in the reboiler is used to separate the heaviest components and most of this energy is discarded as vapor condensation in the overhead cooler. In this study, the first two columns of the separation process are replaced with the Petlyuk column. A structural design was exercised by a stage to stage computation with an ideal tray efficiency in the equilibrium condition. Compared to the performance of a conventional system of 3-column model, the design outcome indicates that the procedure is simple and efficient because the composition of the liquid component in the column tray was designed to be similar to the equilibrium distillation curve. An analysis of the performance of the new process indicated an energy saving of 12.3% under same total number of trays and with a saving of the initial investment cost.

• Korean Chemical Engineering Research
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• v.48 no.6
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• pp.725-730
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• 2010

The fully thermally coupled distillation columns(FTCDC) are thermodynamically more efficient than conventional columns. Despite these advantages, industry has been reluctant to use FTCDC. This can be largely attributed to the lack of established design procedures and column operability. In this study, the $3{\times}3$control structure was applied to control the FTCDC which was simulated using Aspen HYSYS on the possible control structure of 4 kinds and control performance was investigated. As the result of dynamic simulations, one of the proposed structures had better controllability of product compositions and control efficiency was evaluated.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.270-276
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• 2012

In this study, thermally coupled distillation system and conventional two-column process were investigated for extractive distillation. The two processes were simulated and optimized using Aspen plus. Objective function for the optimization was energy consumption and optimization results to reduce energy consumption were used to get guidelines for design and operation for the two extractive distillation processes. Comparison of these two processes showed that thermally coupled distillation system provided better energy efficiency and lower capital cost than conventional distillation system.

• Korean Chemical Engineering Research
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• v.46 no.5
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• pp.892-897
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• 2008

A new ethanol dehydration process utilizing a thermally coupled distillation column is proposed to reduce the energy requirement of the existing dehydration processes. An entrainer of benzene is used in the proposed system having the column profile similar to the equilibrium composition profile for the maximum distillation column efficiency, and the feed composition is arranged to close to the boundary of different distillation regions. It is found that the proposed distillation system gives some 18% of energy saving over the existing process. In addition, design guidelines are suggested for other azeotropic distillation process.

• Korean Chemical Engineering Research
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• v.45 no.1
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• pp.52-56
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• 2007

Though a reactive distillation column reduces energy requirement and gives easy separation of azeotropic mixture to result in wide practical applications in field, its design is difficult. On the other hand, a commercial design software used largely in chemical process design and performance evaluation can solve the problem, but the addition of reaction into the tray is not simple. In this study the addition is implemented to make the process simulation available, and it is utilized in the design of a TAME process to find the following design guidelines. The addition of reactive trays gives more composition elevation than the composition decrease from the reduction of the trays, and the increase of non-reactive trays does not improve product quality. The elevation of reboiler heat duty lowers the product quality by the reduction of residence time in reactive tray and conversion.

• Proceedings of the KAIS Fall Conference
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• 2002.05a
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• pp.127-129
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• 2002

본 연구는 반도체 및 LCD Photo 공정에서 발생되는 폐액의 재자원화를 위한 공정설계 data와 재자원화 기술의 성능향상을 위한 기초 자료를 제공하는데 있다. 재자원화 증류탑의 설계를 위한 공정모사를 통하여 공정폐액 재자원화의 최적조건을 설계할 수 있는 기초자료를 제안하였다.

• Korean Chemical Engineering Research
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• v.56 no.1
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• pp.29-41
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• 2018

Separating a mixture having an azeotrope or low relative volatility with single distillation column is difficult. Separating water-acetic acid mixture and water-ethanol mixture with a distillation column consumes a lot of energy. Pervaporation membrane can be used to separate the mixture in the concentration region where separation is difficult with distillation. We simulated a distillation-membrane hybrid process where membrane is located on the head of the distillation column for efficient separation of water-acetic acid and water-ethanol mixture. Permeability data were obtained from experiments and literature. We formulated an optimization problem for the process with total annual cost (TAC) as an objective function and major design variables as optimization variables. Major optimization variable affecting TAC of the hybrid process was shown to be distillate concentration. We also suggested a simplified optimization procedure to get a close-to-optimal solution.

• Transactions of the Korean hydrogen and new energy society
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• v.30 no.1
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• pp.83-94
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• 2019

LPG is increasingly being used as a clean energy source due to the continuous strengthening of environmental regulations. In addition, the demand of propane which is the basic compound for petrochemicals is increasing for propylene production. In the study, a divided wall column was used as de-propanizer and de-butanizer, which is expected to save large amount of energy among the four conventional distillation columns used for processing LPG. The simulation results showed a decrease of energy duty with ESI by 30.30% using two divided wall columns. Furthermore, simulation case studies were carried out with respect to design and operation condition. The main column tray and withdrawal tray were determined from the design case studies while the internal liquid flow and vapor flow were decided from the operating case studies. Also, ESI of 1.06% could be achieved from the case studies. According to the results, the simulation method used showed that it is greatly helpful to the design and evaluate a highly efficient divided wall column.