• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.259-264
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• 2009

Most of the fossil power plants firing lower grade coals are challenged with maintaining good combustion conditions while maximizing generation and minimizing emissions. In many cases significant derate, availability losses and increase in unburned carbon levels can be attributed to poor combustion conditions as a result of poorly controlled local fuel and air distribution within the boiler furnace. The poor combustion conditions are directly related to the gas flow deviation in upper furnace and convection tube-bank but a less reported issue related to in large-scale oppose wall fired boilers. In order to develop a on-line combustion monitoring system and suggest an alternative heat flux estimation method at tube bank, which is very useful information for boiler design tool and blower optimizing system, field test was conducted at operating power boiler. During the field test the exhaust gases' temperature and tube metal temperature were monitored by using a spatially distributed sensors grid which located in the boiler's high temperature vestibule region. At these locations. the flue gas flow is still significantly stratified, and air in-leakage is minimal which enables tracing of poor combustion zones to specific burners and over-fire air ports. Test results showed that the flue gas monitoring method is more proper than metal temperature distribution monitoring for real time combustion monitoring because tube metal temp. distribution monitoring method is related to so many variables such as flue gas, internal flow unbalance, spray etc., Heat flux estimation at the tube bank with flue gas temp. and metal temp. data can be alternative method when tube drilling type sensor can't able to use.

• Particle and aerosol research
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• v.15 no.2
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• pp.57-65
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• 2019

Recently, there has been much research on the effect of fine dust on human body with increasing interest in the fine dust. Thermal power plant, which is considered as one of the main sources of fine dust, is reported to be responsible for 14% of the total amount of domestic fine dust in the Republic of Korea. Therefore, dust collecting devices in the thermal power plant need to be improved. In this study, the electrostatic precipitator (ESP) was considered to substitute for a mist eliminator used in flue gas desulfurization facility. By considering real situation in the flue gas desulfurization facility, the collection efficiency of the ESP was evaluated by using the sprayed limestone slurry particles. The collection efficiency of the ESP was higher than that of the mist eliminator, showing the possibility of replacing the mist eliminator with the ESP in flue gas desulfurization facility.

• 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.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.12
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• pp.2247-2254
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• 2000

This study was carried out to investigate the reaction characteristics of NOx with reagents to grope the power consumption rate reduction and NOx removal rate improvement for the non-thermal plasma denitrification process. The experiments were performed using the real flue gas and wire-plate type plasma reactor. and the flow rate of real flue gas is $20Nm^3/hr$. Paraffinic and olefinic hydrocarbons and ammonia were used as reagents. Olefinic hydrocarbon oxidizes NO more actively than paraffinic hydrocarbon under the non-thermal plasma conditions, resulting in the generation of large amount of $NO_2$ and a very small amount of CO. When the initial NOx concentration increases. oxidation rate of NO decreases and the consumption rate of olefinic hydrocarbon increases significantly. On the other hand. $NH_3$ did not promote reduction reaction with NO under non-thermal plasma conditions. however, there was a tendency that the NHa was effective to remove the $NO_2$ oxidized by olefinic hydrocarbon.

• Journal of environmental and Sanitary engineering
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• v.22 no.2
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• pp.9-20
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• 2007

The incineration process has commonly used for wastes amount reduction and thermal treatments of pollutants as the technologies accumulated. However, the process is getting negative public images owing to matter of hazardous pollutants emission. Specially dioxins became a main issue and were mostly emitted from municipal solid wastes incineration. In this reason, pyrolysis/gasification/melting process is presented as an alternative of incineration process. The pyrolysis/gasification/melting process, a novel technology, is middle of verification of commercial plant and development of technologies in Korea. But the survey about the pollutant emission from the process, and background data in these facilities is necessary. So in this survey, t is investigated that the behavior of chlorobenzenes and chlorophenols in plasma type pyrolysis/gasification/melting plant of pilot scale. We investigated discharging behavior of each phase of chlorobenzene through each process in the plsasma type pyrolysis/gasification/melting process. From this result, it was found that about 99 percent of particle-phase chlorobenzene was removed, but on the other hand gas-phase chlorobenzene was increased by about 600 percent through heat exchanger, flue gas cooling, system and semi dry absorption bag filter(SDA/BF). Also, this investigation presented that di-chlorobenzene(DCB) tri-chlorobenzene(TCB), tetra-chlorobenzene(TeCB), penta-chlorobenzene (PCB), except mono-chlorobenzene(MCB) and hexa-chlorobenzene(HCB) were increased through the flue gas cooling system and the semi dry absorption bag filter(SDA/BF). It was investigated that concentration of particle-phase chlorophenol was decreased by about 66 percent, but on the other hand, concentration of gas-phase chlorophenol was increased by about 170 percent through heat exchanger, flue gas cooling system, and semi dry absorption bag filter(SDA/BF). Also, it was found that di-chlorophenol(DCP), tri-chlorophenol(TCP), and penta-chlorophenol(PCP) were increased through the flue gas cooling system, and the semi dry absorption bag filter(SDA/BF). It can be considered that small-scale pilot facility and short investigation period might cause the concentration increase through the flue gas cooling system and the semi dry absorption bag filter(SDA/BF). A further study on real-scale pilot facility and accurate investigation may be required.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2010.04a
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• pp.591-593
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• 2010

• Journal of Environmental Science International
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• v.22 no.7
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• pp.847-853
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• 2013

Functionalized adsorbent has been synthesized by piperazine(Pz) on activated carbon. Quantitative estimations of $CO_2$ were undertaken using gas chromatography with GC/TCD and the prepared adsorbents were characterized by BET surface area and FT-IR. It was also studied effect of various parameters such as piperazine loadings and adsorption temperature. The specific surface area decreased from $1212.0m^2/g$ to $969.8m^2/g$ by impregnation and FT-IR revealed a N-H functional group at about $1400cm^{-1}$ to $1700cm^{-1}$. The $CO_2$ adsorption capacity at $20^{\circ}C$ and $50{\sim}100^{\circ}C$ was as follow: AC > Pz(10)-AC> Pz(30)-AC> Pz(50)-AC at $20^{\circ}C$ and Pz(10)-AC > AC > Pz(30)-AC> Pz(50)-AC at $50{\sim}100^{\circ}C$. Therefore, for high temperature flue gas condition, the Pz(10)-AC showed the highest adsorption capacity due to physical adsorption and chemical adsorption by amino-group content. The results suggest that activated carbon impregnated with Pz is an effective adsorbent for $CO_2$ capture from real flue gases above $50^{\circ}C$.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.11
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• pp.1977-1983
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• 2000

SCR(selective catalytic reduction) pilot plant for reduction of the nitrogen oxides using diesel oil as a reductant was installed at the NG(natural gas) fired combined cycle and the activity of Pt(0.3%)/Zeolite catalyst was studied in real flue gas condition according to the amount of reductant. reaction temperature and space velocity. NOx conversion gradually increased with increasing the diesel oil concentration up to C/N ratio 5.5(C/N ratio: the ratio of the number of carbon atom to the number of NOx molecules included in the flue gas). Increasing the reaction temperature. NOx conversion increased and reached a maximum conversion of 50% at $190^{\circ}C$. NOx conversion did not changed with increasing the space velocity up to 18,500/hr and then gradually decreased. These results reveal the potential for diesel oil as a reductant for de-NOx SCR process.

• Korean Chemical Engineering Research
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• v.54 no.6
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• pp.838-846
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• 2016

Most of combustion processess used in industries require recovering or removing flue gas components. Recently a new MBA (moving bed adsorption) process for recovering $CO_2$ using zeolite 13X was developed. In this study, adsorption experiments for carbon dioxide, nitrogen, sulfur dioxide, and water vapor on zeolite 13X were carried out. Adsorption equilibrium and adsorption rate into solid particle were investigated. Langmuir, Toth, and Freundlich isotherm parameters were calculated from the experiment data at various temperatures. Experimental results were consistent with the theoretically predicted values. Also $CO_2$ adsorption amount was measured under the conditions with impurities such as $SO_2$ and $H_2O$. Binary adsorption data were well fitted to the extended Langmuir isotherm using parameters obtained from pure component experiment. However, $H_2O$ impurity less than, roughly, ${\sim}10^{-5}H_2O\;mol/g$ zeolite 13X enhanced slightly $CO_2$ adsorption. Spherical particle diffusion model well described experimentally measured adsorption rate. Diffusion coefficients and activation energies of $CO_2$, $SO_2$, $N_2$, $H_2O$ were obtained. Diffusion coefficients of $CO_2$ and $SO_2$ decreased with small amount of preadsorbed impurity. Parameter values from this study will be helpful to design of real commercial adsorption process.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.2
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• pp.238-248
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• 2008

This study investigated mercury emission at various combustion conditions and analyzed mercury species in flue gas from coal combustion at a laboratory scale furnace in coal. The results of this study can be used to predict and to assess mercury emission at coal boilers and power plants. The coal used in the plants generally contains about $0.02{\sim}0.28\;mg$ of mercury per kg. Bituminous and anthracite coal used for the experiment contained 0.049 and 0.297 mg/kg of mercury, respectively. Mercury emissions during coal combustion at temperatures range of $600^{\circ}C$ to $1,400^{\circ}C$ was measured and analysed using Ontario Hydro method; the speciation changes were also observed in mercury emissions. The results showed higher fraction of elemental mercury than that of oxidised mercury at most temperatures tested in this experiment. The fraction of elemental mercury was lower in combustion of anthracite coal than in bituminous combustion. As expected, equilibrium calculations and real power plants data showed good similarity. The distribution of particle size in flue gas had the higher peak in size above $2.5\;{\mu}m$. However the peak of mercury enrichment in dust was at $0.3\;{\mu}m$, which could be easily emitted into atmosphere without filtration in combustion system. When the CEA(Chemical equilibrium and Application) code was used for combustion equilibrium calculation, Cl was found to be the important component effecting mercury oxidation, especially at the lower temperatures under $900^{\circ}C$.