• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06a
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• pp.63-67
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• 1996

• Proceedings of the Membrane Society of Korea Conference
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• 2003.11a
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• pp.168-171
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• 2003

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1997.04a
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• pp.135-137
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• 1997

• 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.

• Polymer(Korea)
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• v.32 no.6
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• pp.593-597
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• 2008

To separate carbon dioxide from a flue gas, membranes for gas separation was fabricated from polystyrene-b-polybutadiene (SB) diblock copolymer blends with poly(phenylene oxide), PPO. SB diblock copolymer formed miscible blends with PPO in the experimental range (lower than or equal to 70 wt% PPO). When the blend contained PPO whose composition is in the range of 40-50 wt%, the discontinuous phase of polybutadiene block in SB diblock copolymer, was changed to discrete phase, while polystyrene blocks containing PPO was changed to the continuous phase. A sudden decrease of the gas permeability and a sudden increase of the gas selectivity was observed at these blend compositions. A gas separation membranes having excellent mechanical properties and exhibiting advantages in gas permeability and selectivity could be fabricated from blends containing more than 50 wt% PPO.

• Journal of Biosystems Engineering
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• v.25 no.3
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• pp.221-226
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• 2000

Hot air heater with light oil burner is the most common heater for greenhouse heating in the winter season in Korea. However, since the thermal efficiency of the heater is about 80∼85%, considerable unused heat amount in the form of exhaust gas heat discharges to atmosphere. In order to capture this exhaust heat a heat recovery system for plant bed heating in the greenhouse was built and tested in the hot air heating system of greenhouse. The heat recovery system is made for plant bed or soil heating in the greenhouse. The system consisted of a heat exchanger made of copper pipes, ${\Phi}12.7{\times}0.7t$ located in the rectangular column of $330{\times}330{\times}900mm$, a water circulation pump, circulation plastic pipe and a water tank. The total heat exchanger area is 1.5$m^2$, calculated considering the heat exchange amount between flue gas and water circulated in the copper pipes. The system was attached to the exhaust gas path. The heat recovery system was designed as to even recapture the latent heat of flue gas when exposing to low temperature water in the heat exchanger. According to the performance test it could recover 45,200 to 51,000kJ/hr depending on the water circulation rates of 330 to $690\ell$/hr from the waste heat discharged. The exhaust gas temperature left the heat exchanger dropped to $100^{\circ}C$ from $270^{\circ}C$ by the heat exchange between the water and the flue gas, while water gained the difference and temperature increased to $38^{\circ}C$ from $21^{\circ}C$ at the water flow rate of $690\ell$/hr. By the feasibility test conducted in the greenhouse, the system did not encounter any difficulty in operations. And, the system could recover 220,235kJ of exhaust gas heat in a day, which is equivalent of 34% of the fuel consumption by the water boiler for plant bed heating of 0.2ha in the greenhouse.

• Korean Chemical Engineering Research
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• v.57 no.4
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• pp.492-500
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• 2019

In this study, the effect of chemical additives on the reduction of fine particles was identified in $9.2MW_e$ commercial scale circulating fluidized bed boiler firing bituminous coal. Futhermore, a simple and effective method of fine particle collection has been developed to collect the fine particles of the boiler during fossil fuel combustion. Chemical additives were used to reduce particles below 10 PM in the flue gas, and borax solution was used as a chemical additive. In order to identify the particle behavior of PM 10 or less among the collected fine particles, it was analyzed through particle size analyzer and SEM analysis. The Borax solution tends to absorb molten mineral in the flue gas and make fine particles grow. As a result, it was analyzed that particles smaller than $10{\mu}m$ were reduced by using borax solution.

• Journal of the Korean Society of Tobacco Science
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• v.28 no.2
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• pp.67-74
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• 2006

This study was carried out to investigate the changes of essential oils in flue-cured leaf tobacco during aging for 21 months. The threshed leaf tobacco(BlO) produced in 2002 crop year was aged for 21 months in the warehouse of Oc-Cheon Leaf Tobacco Processing Factory. The leaf tobacco were sampled at three month intervals for analysis of volatile compounds. Volatile compounds were identified by GC/MS and comparison of gas chromatographic retention time with those of the authentic standard. The total of 75 compounds from the steam volatile concentrate of the flue-cured leaf tobacco were identified; they were 15 hydrocarbons, 12 alcohols, 3 aldehydes, 18 ketones, 7 esters, 10 acids, 3 phenols, 4 furans, 2 pyrrols and 1 pyridine. The major components of essential oil were neophytadiene, solanone, megastigmatrienone and phytol. After a aging period of 21 months, most of volatile compounds showed a gradual increasing tendency.

• Analytical Science and Technology
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• v.12 no.1
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• pp.61-67
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• 1999

Two of municipal waste incinerators were selected as surveying facilities to research on the emission of dioxin and precusors. The sampling of flue gas and analysis was performed in the selected facilities. From the result, the emission patterns of dioxin and precusors, their relatership were examined. The toxic equivalency quantity(TEQ) of dioxin concentration was evaluated in two municipal waste incinerators. The 76.24% and 60.84% of total dioxin concentration in A and B incinerator were made up of the penta-, hexa- and hepta-chlorinated dibenzo-p-dioxin, respectively. Therefore, to reduce the dioxins in flue gas have to control the formation of furans. The chlorobenzenes and chlorophenols were analyzed in two incinerators. The 1,2,4,5-tetrachlorobenzene, penta-, and hexachlorobenzene are discharged and 2,4,6-trichlorophenol, 2,3,4,6-tetrachlorophenol and pentachlorophenol are discharged mainly in A and B municipal waste incinerators.

• Applied Chemistry for Engineering
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• v.23 no.3
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• pp.333-338
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• 2012

To verify the utilization of fluff refuse derived fuel (RDF) as energy source, the combustion charateristic has been studied by an experimental combustion furnace under various temperatures. The characteristics of flue gas, dust and residue from fluff RDF combustion has been analyzed and compared with those of pelletized RDF. From this work, it was found that the incomplete combustion of fluff RDF was greater than that of pelletized RDF because the combustion reaction rate of fluff RDF was faster than that of pelletized RDF, and oxgen concentration in fluff RDF combustion decreased rapidly. It was also found that carbon monoxide concentration of flue gas from fluff RDF combustion increased with combustion temperature because the oxygen consumption and the incomplete combustion increased. Therefore, it is felt that the combustion operation conditions of fluff RDF should be carefully determined.