• Journal of Korean Society for Atmospheric Environment
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• v.19 no.4
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• pp.427-436
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• 2003

This study is to establish a waste bed combustion model that can be available to assist the design of incinerators for efficient operation control of municipal waste incinerators. An unsteady one -dimensional bed combustion modeling was developed which incorporates the various sub-process models and solves the governing equations for both gases and solids in the waste bed combustion phenomena. The combustion characteristics and the properties of the combustion gas released from the bed were investigated by using a developed model. Besides, a sub-model which predicts the formation and destruction of nitrogen oxides in the waste bed was also developed as a post-processor for the waste combustion model. It is found that the reduction rate of nitrogen oxides is enhanced in the char layer.

• 한국연소학회:학술대회논문집
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• 1999.10a
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• pp.129-138
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• 1999

In this paper, our main issue is that establishing the control procedure of continuous gas flow rate according to combustion fan RPM. For this, first, we decide the optimum operating condition of gas swirl burner through analysis of combustion characteristics - thermal efficiency, combustion efficiency and exhaust gases such as CO, $CO_{2}$, $O_{2}$, $NO_{x}$ and THC. Second, fuel gas flow rate of gas valve is decided with considering excess air ratio and combustion fan RPM is decided by the target of combustion air flow rate. Finally, experimental operating equation is acquired by regression for gas valve and combustion fan. This equation is the control equation of continuous gas flow rate and always gas flow rate is decided by combustion fan operating RPM.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.6
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• pp.159-164
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• 2007

The purpose of this study is to reduce harmful emission gases in the range of stable combustion without loss of a thermal efficiency. Therefore, effects of both exhaust gas recirculation(EGR) and synthetic gas addition on engine performance and emission were investigated in a gasoline engine. Synthetic gas(syngas), which is in general prepared from reforming gasoline, was utilized in order to promote stable combustion. The major components of syngas are H2, CO and $N_2$ gases. The percentage of syngas addition was changed from 0 to 30% in energy fraction and EGR rate was varied up to 30%. As a result, $COV_{IMEP}$ as a parameter of combustion stability was decreased and THC/$NO_X$ emissions were reduced with the increase of syngas addition. And $COV_{IMEP}$ was increased with the increase of EGR but $NO_X$ emission was greatly reduced. In addition, under the region where the EGR rate is around 20%, thermal efficiency was improved.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.863-866
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• 2011

Recently environmental issue is more and more emphasized and 'Green Growth' became on of the key words of this Government. Based on this trend, the exhaust gases out of the gas generator cycle and the staged combustion cycle LRE whose propellants are kerosene and LOx were compared. For this purse, 8 tonf class of each cycle engine was designed and the amount and the components of the gases were investigated by using CEA. As expected, the staged combustion cycle engine generates less pollutants than the other cycle. In addition, the graphite that is generated by the gas generator can be reacted with the oxygen in the atmosphere creating additional pollutants.

• Journal of ILASS-Korea
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• v.3 no.1
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• pp.19-26
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• 1998

The effect of mixture component makes a nelay time and a long total combustion period $\tau_{p\;max}$. The flame propagation delay $\tau_{df}$ was determined by the record of current ion. The pressure release delay $\tau_{dp}$ and $\tau_{p\;max}$ were determined by the indicated pressure diagram in constant volume of the combustion chamber. The results are as follows: 1) The ignition delay $\tau_t$ time takes the minimum value around $\Phi=1.15$. 2) $\tau_{df}$ and $\tau_t$ time increased according to the increases of the concentrated dilution gases, because the adiabatic flame temperature decreased due to the increases of the heat capacity. But dilution gases have little effect on flame nucleus formation delay 3) The relation between $\tau_t$ time and reciprocal laminar burning velocity is almost linear. 4) The increase of the propagation length is accompanied with increased ratio of the $\tau_{df},\;\tau_{dp},\;\tau_{t},\;\tau_{p\;max}$.

• 보일러설비
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• s.81
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• pp.101-102
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• 2000

• Analytical Science and Technology
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• v.26 no.2
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• pp.120-124
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• 2013

It was studied to analyze the $CO_2$, CO, $SO_2$ standard gases of combustion gases by the open path FT-IR spectrometer with passive mode for remote analysis of air pollutant and volcano gases without IR lamp. As result, it was confirmed to have good linearity with more than 0.9 as correlation coefficients on the calibration curve of $CO_2$, CO concentration by MLR method. But in the case of $SO_2$, because the correlation coefficients were 0.88, the linearity could be lower. Finally, the concentration of three gases was predicted on in-site fire experiment under the condition of quantitative analysis. It could measure high $CO_2$ concentration as predicted result, but didn't measure the CO and $SO_2$. According to the result, it was possible to measure the combustion gases to long distance by only open path FT-IR spectrometer without infrared lamp.

• Fire Science and Engineering
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• v.17 no.1
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• pp.33-39
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• 2003

The purpose of this study is to evaluate flame retardant performance, thermal stability and toxicity of combustion gases for some commercial wallpapers. ID evaluate flame retardant performance 45 degree combustion experiment method was used and thermal stability was evaluated using DSC and TGA apparatus (OSC-50/Shimadzu, TGA2050/TA Instruments Inc) . Concentrations of CO, $CO_2$, HCN and HCI were measured with (GASTEC/Japan, MSA400 Gas Monitor/Infitron Inc) and toxicity indices using NIST N-Gas Model were applied to evaluate the toxicity of combustion gases. The evaluation produced the following results : First, paper cork and PVC wallpaper treated with flame retardants were found to be suitable for flame retardant performance standards. Second, paper, cork and PVC wallpaper non-treated with flame retardants were shown to be relatively more hazardous because they had greater calorific values and a faster decomposition time than the flame retardant treated wallpapers. Third, the toxicity indices of non-treated wallpapers were found to be higher than those of treated wallpapers, and the toxicity index of PVC wallpapers was higher than those of paper and cork wallpapers.

• Journal of the Korean Society of Combustion
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• v.10 no.3
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• pp.1-9
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• 2005

The characteristics of co-combustion of Korean anthracite and bituminous coal was determined in a TGA and a lab-scale CFB reactor. The combustion reactivity of Korean anthracite (E = 51.2 kcal/mol) was much lower than that of bituminous coal (E = 14.5 kcal/mol). As the addition amount of the bituminous coal into the anthracite was increased, the reactivity of the anthracite was found to be improved. The effluent rate of the emission gases from the CFB reactor was not changed appreciably when each coal burned. As the bituminous coal was added, however, the effluent rate of the emissions was increased. The unburned carbon in fly ash from the CFB reactor was decreased with increasing the ratio of bituminous coal in co-combustion. But as the ratio of the bituminous coal was larger than 40 %, the combustion reactivity was not increased any more.

• Korean Chemical Engineering Research
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• v.47 no.4
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• pp.512-517
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• 2009

$SO_2$ concentrations in oxy-fuel combustion flue gases increases about three times as high as that of conventional air combustion system owing to the flue gas recirculation for the control of combustion temperature. So the desulfurization reaction is different from that of the conventional air combustion system due to exceptionally high $CO_2$ and $SO_2$ concentration. In this study, drop tube furnace(DTF) system was used to investigate the desulfurization characteristics of limestone in oxy-fuel combustion furnace. The experiments were performed under $O_2/CO_2$ atmosphere to examine the effect of operating variables such as reaction temperatures, Ca/S ratios and inlet $SO_2$ concentrations on the $SO_2$ removal efficiencies. $SO_2$ removal efficiency increased with reaction temperature, Ca/S ratio and inlet $SO_2$ concentration. And the addition of water vapor resulted in about 4~6% of increase in $SO_2$ removal efficiency.