• Membrane Journal
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• v.16 no.3
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• pp.204-212
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• 2006

A numerical analysis was carried out for separation of carbon dioxide from carbon dioxide/nitrogen gas mixture by a polyethersulfone hollow fiber membrane which has shown a good stability against plasticization by carbon dioxide and an excellent separation efficiency fur carbon dioxide from its gas mixture. A computer program for carbon dioxide separation was developed using the Compaq Visual Fortran 6.6 software. Governing module equations were thought to be an initial-value problem and the nonlinear ordinary differential equations were simultaneously solved using the Runge-Kutta-Verner fifth-order method. From results of numerical analysis, the carbon dioxide partial pressure of the feed stream, the pressure ratio of the feed side to the permeate side and the feed gas residence time at the inside of a membrane were found to be very important factors to affect the permeation characteristics of carbon dioxide.

• Journal of Hydrogen and New Energy
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• v.21 no.1
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• pp.72-79
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• 2010

This paper is studying the selective separation of methane and carbon dioxide which are the main ingredients of biogas. Adsorption performance of molecular sieve 13x for carbon dioxide seems to be reasonable. In this experiments carbon dioxide contains about 3~5 ppm of methane and it is impossible to obtain high purity carbon dioxide. Applying the low temperature technique, it is possible to separate methane and carbon dioxide from bio gas. PRO II simulation shows results a small change of liquefaction temperatures and no difference with the used thermodynamic models. Applying low temperature technique, It is possible to separate carbon dioxide and methane from biogas.

• Korean Chemical Engineering Research
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• v.61 no.4
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• pp.619-626
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• 2023

Primary and secondary amine-based sorbents were synthesized to investigate the operation capacity for the carbon dioxide separation TSA process. (3-Aminopropyl) triethoxysilane was used as a primary amine precursor as a crosslinking agent to synthesize a secondary amine precursor in which amine groups were crosslinked with a crosslinking agent. Carbon dioxide absorbed by primary amines is completely separated above 170 ℃. The working capacity of the primary amine absorbent was less than 2% when regenerated at 130℃. The secondary amine absorbent has a higher carbon dioxide separation capacity at a lower regeneration temperature than the primary amine absorbent. The secondary amine absorbent could predict process operation performance of about 6.5% with 2% carbon dioxide absorption and 100% carbon dioxide regeneration conditions. Therefore, it was found that the working capacity of the secondary amine absorbent was higher than that of the primary amine.

• Progress in Superconductivity and Cryogenics
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• v.23 no.3
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• pp.14-19
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• 2021

The reduction of carbon dioxide emissions becomes a global issue, the main source of carbon dioxide emissions in the Asian region is the energy conversion sector, especially coal-fired power plants. We are working to develop technologies that will at least limit the increase in carbon dioxide emissions from the thermal power plants as one way to reduce carbon dioxide emissions. Our research aims to reduce carbon dioxide emissions by removing iron oxide scale from the feedwater system of thermal power plants using a superconducting high-gradient magnetic separation (HGMS) system, thereby reducing the loss of power generation efficiency. In this paper, the background of thermal power plants in Asia is outlined, followed by a case study of the introduction of a chemical cleaning line at an actual thermal power plant in Japan, and the possibility of introducing it into the thermal power plants in China based on the results.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.4
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• pp.471-478
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• 2011

A series of laboratory experiments carried out to investigate the particle separation efficiency and flotation characteristics using $CO_2$ bubbles. The primary objective of this study was to find out the feasibility of $CO_2$ bubbles as an applicable unit of flotation process in tap-water and wastewater treatment plant. The fundamental measurements were conducted to characterize the $CO_2$ bubble from the physical viewpoint in water including bubble size distribution and rising velocity under various operational conditions. In addition, the removal efficiency of solid was experimented using the lab scale plant applied $CO_2$ bubbles, namely the dissolved carbon dioxide flotation (DCF) process. The DCF process using carbon dioxide bubble, which is an advantage as the decrease and the reuse of Green-House gas, can be a promising technology as an water treatment process. On the other hand, the further research to decrease the bubble size distribution of $CO_2$ is required to enhance the particle separation efficiency.

• Membrane Journal
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• v.17 no.2
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• pp.134-139
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• 2007

Experimental and numerical analysis were performed for separation of carbon dioxide from carbon dioxide and nitrogen gas mixture using a polyethersulfone hollow fiber membrane. The experimental results were compared with those obtained at the same operating condition by the numerical analysis. It was observed that there was a big difference between the experimental results and those by a numerical analysis where the permeance of carbon dioxide and its ideal selectivity over nitrogen were obtained from the pure gas permeation. Therefore, the permeance of carbon dioxide and its selectivity were obtained from the separation experimental results using the numerical analysis as a function of the mole fraction of carbon dioxide, the feed pressure and the permeate pressure in the gas mixture. The results of the numerical analysis using the selectivity obtained from the gas mixture were in good agreement with those of the experimental.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.17-24
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• 2021

The development of a new sorbent for carbon dioxide depends on several factors, such as fast adsorption/absorption velocity, hydrophobicity, and lower regeneration temperature than commercial sorbent. In this study, aminosilane grafted activated carbon was synthesized to capture CO2. Methyltrimethoxysilane (MTMS) and 3-aminopropyl-triethoxysilane (APTES) were used as the grafting precursor of the amine functional group. The APTES grafting activated carbon showed higher sorption property than MTMS used one. The characteristics of the separation mechanism of carbon dioxide were examined by measuring the adsorption capacity according to temperature and carbon dioxide partial pressure. The absorption capacity of carbon dioxide was similar to amine grafting activated carbon and activated carbon at 25℃, but amine-grafted activated carbon was higher at 75℃. The amine functional group-grafted activated carbon showed higher absorption capacity than activated carbon with a 1% carbon dioxide partial pressure. Aminosilane grafting of activated carbon was chemically absorbed but also showed the characteristics of physical adsorption. The reforming activated carbon with an amine functional group grafted solid absorption/adsorption sorbent would significantly impact the material engineering industry and carbon dioxide adsorption process. The functionalized sorbent is a high-performance composite material. The developed sorbent may have applications in other industrial processes of absorption/adsorption and separation.

• Membrane Journal
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• v.12 no.3
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• pp.121-142
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• 2002

The $CO_2$ emission is the largest contribute for the green house effect. Among the existing chemical separation processes, the membrane separation technology is(/will be) the most potential process for $CO_2$, separation from flue gas. Based on the solution-diffusion theory and physical properties of carbon dioxide/nitrogen and the permeation data in the literature, the relationships between physico-chemical structures of polymeric membrane materials and the perm-selectivities for $CO_2$/$N_2$ gases were described in detail. The progress of membrane module and process development was introduced briefly. Finally, the worldwide research activity including South Korea's for carbon dioxide separation by membrane technology were introduced through the survey of papers and technical reports published.

• Journal of Hydrogen and New Energy
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• v.34 no.1
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• pp.83-89
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• 2023

In this study, a computer simulation work has been performed for the separation of electronic grade highly pure carbon dioxide more than 7 N purity through a cryogenic distillation process. For the cold utility as a cooling medium for a condenser of the cryogenic distillation column, propylene was utilized as a refrigerant in the vapor-recompression refrigeration cycle. Through this work, it was concluded that the cryogenic distillation column with two stage compression and refrigeration cycle were essential to obtain a highly-pure liquefied CO₂.

• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.128-134
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• 2012

The pilot scale experiments can handle the flue gas up to 1,000 $Nm^3/hr$ for separation of carbon dioxide included in real flue gas at coal-fired power plant. The operational characteristics was analyzed with the main experimental variables such as flue gas flow rate, absorbent circulation rate using chemical absorbents mono-ethanolamine( MEA) and 2-amino-2-methyl-1-propanol(AMP). The more flue gas flow rate decreased in 100 $m^3/hr$ in the MEA 20 wt% experiments, the more carbon dioxide removal efficiency was increased 6.7% on average. Carbon dioxide removal efficiency was increased approximately 2.8% according to raise of the 1,000 kg/hr absorbent circulation rate. It also was more than 90% at $110^{\circ}C$ of re-boiler temperature. Carbon dioxide removal efficiency of the MEA was higher than that of the AMP. In the MEA(20 wt%) experiment, carbon dioxide removal efficiency(85.5%) was 10% higher than result(75.5%) of ASPEN plus simulation.