• Proceedings of the Korea Air Pollution Research Association Conference
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• 2006.04a
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• pp.575-576
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• 2006

• Membrane Journal
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• v.17 no.3
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• pp.197-209
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• 2007

In this study, a multi-staged pilot-scale membrane plant was constructed and operated for the separation of $CO_2$ from LNG-fired boiler flue gas of 1,000 $Nm^3/day$. The target purity and recovery ratio of $CO_2$ required for the pilot plant were 99% and 90%, respectively. For this purpose, we previously developed the asymmetric polyethersulfone hollow fibers and evaluated the effects of operating pressure and feed concentration of $CO_2$ on separation performance[1,2]. The permeation data obtained were also analyzed in relation with the numerical simulation data using counter-current flow model[3,4]. Based on these results, we designed and prepared the demonstration plant consisting of dehumidification process and four-staged membrane process. The operation results using this plant were compared with the numerical simulation results on multi-staged membrane process. The experimental results matched well with the numerical simulation data. The concentration and the recovery ratio of $CO_2$ in the final stage permeate stream were ranged from $95{\sim}99%$ and $70{\sim}95%$, respectively, depending on the operating conditions. This study demonstrated the applicability of the membrane-based pilot plant for $CO_2$ recovery from flue gas.

• Journal of Advanced Marine Engineering and Technology
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• v.18 no.4
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• pp.84-93
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• 1994

The purpose of this study is to modify the kerosene furnace, which is forced flue type with 15000kcal capacity, to gas furnace satisfying for CITY gas, LNG gas and LPG gas. The gas furnace, a kind of gas appliance, is mainly used for heating houses by combusion of gas. This paper describes briefly the design technology for gas burner which is most important in replacing kerosene fuel with gas fuel. Especially, the design for gas nozzle is constructed by theoretical and experimental method. It is found that the experimental results of the modified gas burner are good agreement with the theoretical results for calorific value and combustion efficiency. The result of this study will contribute in the design skill and of gas burner and similar gas appliance, and the pursuit for reduction of fuel cost as well as atmospheric pollution.

• Journal of Environmental Health Sciences
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• v.11 no.1
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• pp.9-14
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• 1985

This experiment was carried out to study on the effect of SO$_2$ gas to chemical composition of tobacco leaves during flue-curing. The results were as follows: SO$_2$ gas in briquet was the major factor to damage with tobacco leaves. The damage only occured in a presence of moisture in tobacco leaves, it did not occured after color fix'lng stage which is a little leaf moisture. The danger of damage to tobacco leaves lies in 10ppm of SO$_2$ gas concentration. Follow with the SO$_2$ gas concentration increased, sugar and nitrogen contents became higher, polyphenol contents were loss, and the quality of tobacco leaves declined.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2007.10a
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• pp.520-521
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• 2007

• Journal of Korean Society of Environmental Engineers
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• v.29 no.6
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• pp.647-653
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• 2007

The ultimate objective of this study is to develop a reliable oxygen-enriched combustion techniques especially for the case of the flue gas recycling in order to reduce the $CO_2$ emissions from practical industrial boilers. To this end a systematic numerical investigation has been performed, as a first step, for the resolution of the combusting flame characteristics of lab-scale LNG combustor. One of the important parameters considered in this study is the level of flue gas recycling calculated in oxygen enriched environment. As a summary of flame characteristics, for the condition of 100% pure $O_2$ as oxidizer without any flue gas recycling, the flame appears as long and thin laminar-like shape with relatively high flame temperature. The feature of high peak of flame temperature is explained by the absence of dilution and heat loss effects due to the presence of $N_2$ inert gas. The same reasoning is also applicable to the laminarized thin flame one, which is attributed to the decrease of the turbulent mixing. These results are physically acceptable and consistent and further generally in good agreement with experimental results appeared in open literature. As the level of $CO_2$ recycling increases in the mixture of $O_2/CO_2$, the peak flame temperature moves near the burner region due to the enhanced turbulent mixing by the increased amount of flow rate of oxidizer stream. However, as might be expected, the flue gas temperature decreases due to presence of $CO_2$ gas together with the inherent feature of large specific heat of this gas. If the recycling ratio more than 80%, gas temperatures drop so significantly that a steady combustion flame can no longer sustain within the furnace. However, combustion in the condition of 30% $O_2/70% $ $CO_2$ can produce similar gas temperature profiles to those of conventional combustion in air oxidizer. An indepth analyses have been made for the change of flame characteristics in the aspect of turbulent intensity and heat balance.

• Journal of the Korean Society of Combustion
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• v.14 no.4
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• pp.25-32
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• 2009

In commercial combustion systems, heavy oil is one of main hydrocarbon fuel because of its economical efficiency. Regarding heavy oil combustion, due to increasing concerns over environmental pollutants such as carbon monoxide, unburned hydrocarbon and nitrogen oxides, development of low pollutant emission methods has become an imminent issue for practical application to numerous combustion devices. Also a great amount of effort has been tried to developed effective methods for practical using of biomass. It is also an important issue to reduce carbon tax. In this paper, an experimental study has been conducted to evaluate the effect of biomass reburning on NOx formation in a heavy oil flamed combustion furnace. Experiments were performed in flames stabilized by a multi-staged burner, which was mounted at the front of the furnace. Experimental tests were conducted using air-carried rice husk powder and LNG as the reburn fuel and heavy oil as the main fuel. The paper reports data on flue gas emissions and temperature distribution in the furnace for several kinds of experimental conditions. NOx concentration in the exhaust has decreased considerably due to effect of reburning. The maximum NOx reduction rate was 62% when the rice husk was used by reburn fuel, however it was 59% when the LNG was used by reburn fuel. The result shows the positive possibility of biomass reburning system for optimal NOx reduction.

• Membrane Journal
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• v.15 no.4
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• pp.310-319
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• 2005

This paper describes the preliminary study on the development of multi-stage membrane demonstration plant for removal of carbon dioxide from flue gas stream being emitted from LNG boiler in thermal power generation plant. The prerequisite requirement is to design and develop the membrane process producing a $99\%\;CO_2$ with $90\%$ recovery from LNG flue gas of 1,000 $Nm^3$/day. Asymmetric polyethersulfone hollow fiber membranes and membrane modules developed in this laboratory[1] were used in this study. Using the permeation data for the hollow fiber membranes, modelling on the membrane module and multi-stage membrane process was done to meet the requirement condition of the process design. The effects of the operating pressure of feed and permeate side and feed concentration on $CO_2$ purity and recovery were investigated experimentally with the developed hollow fiber modules. These experimental results matched well with theoretical modelling results.

• 한국연소학회:학술대회논문집
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• 2006.04a
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• pp.189-193
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• 2006

Experiments were performed to investigate the melting characteristics of pellet fuel made of LDPE and PP for a waste plastic firing boiler. Pellet fuel in a burner goes through conduction, convection and radiation transferred from flame in a furnace, and complex thermo/chemical processes. To figure out effects of ambient temperature and size of pellet on melting time pellets with a diameter from 5 mm to 40 mm were made to contact high temperature flue gas generated by a LNG firing pilot burner. Though melting processes of plastics include complicated heat transfer in a burner, parameters are limited to flue gas temperature and size for the simplicity in this study. From the results, melting times of LDPE and PP with a diameter of 5mm are 63 and 62 secs respectively at 600 $^{\circ}C$ while 677 and 583 sees respectively for a diameter of 40 mm. At $900^{\circ}C$, melting times of LDPE and PP with a diameter of 5mm are 21 and 24 sees respectively while 408 and 337 secs respectively for a diameter of 40 mm. It is found that melting time of LDPE is longer than that of PP, and melting times of both in general increase with diameter of pellets. It is thought melting is dependent mostly on melting temperature of plastic. It is expected melting times obtained from the study might be taken into account in designing a pellet firing burner for a boiler

• Journal of the Korean Institute of Gas
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• v.27 no.3
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• pp.77-83
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• 2023

Energy consumption is increased by rapid industrialization. As a result, climate change is accelerating due to the increase in CO₂ concentration in the atmosphere. Therefore, a shift in the energy paradigm is required. Hydrogen is in the spotlight as a part of that. Currently 95% of hydrogen is fossil fuel-based reforming hydrogen which is accompanied by CO₂ emissions. This is called gray hydrogen, if the CO₂ is captured and emission of CO₂ is reduced, it can be converted into blue hydrogen. There are 3 technologies to capture CO₂: absorption, adsorption and membrane technology. In order to select CO₂ capture technology, the analysis of the exhaust gas should be carried out. The concentration of CO₂ in the flue gas from the hydrogen production process is higher than 20%if water is removed as well as the emission scale is classified as small and medium. So, the application of the membrane technology is more advantageous than the absorption. In addition, if LNG cold energy can be used for low temperature CO₂ capture system, the CO₂/N₂ selectivity of the membrane is higher than room temperature CO₂ capture and enabling an efficient CO₂ capture process. In this study, we will analyze the flue gas from hydrogen production process and discuss suitable CO₂ capture technology for it.