• Journal of Korean Society for Atmospheric Environment
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• v.18 no.2
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• pp.85-94
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• 2002

In this study, a 3-dimensional numerical model, has been developed applied for the investigation of combustion characteristics, and used to optimize operating conditions in MSW incinerator, in Gwangju. The model developed in this study has been verified by exacting both the predicted and the measured temperature in combustion chamber which has been operated to provide a reference condition. By predictive results, the Sangmoo incinerator has a good characteristics of combustion and low emission however after burning zone produced incomplete products, also probably because the supply of primary air was not enough. Parametric screening studies have been conducted to study optimal operating conditions. For the optimal combustion characteristics, operating conditions should be adjusted with the waste properties.

• Korean Chemical Engineering Research
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• v.52 no.2
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• pp.256-260
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• 2014

Interior of the building is used as a MDF plywood if there is a fire in order to delay the ignition, flame retardant paint, flame retardant solution and flame retardant film are being handled by the flame retardant. Combustion characteristics anf flame retardant performance results can be summarized as follows: General film with a sample showed that short of the criteria in terms of carbonation area, and the results of flame retardant paint, flame retardant solution and flame retardant film products satisfied the criteria. Toxic gases generated in the combustion process results in a film samples using a high incidence of carbon monoxide and the creation of a smoke could be seen. This confirm that is estimated that result from incomplete combustion of PVC film that attach, and displays high toxicity index and hazard class relatively.

• Journal of the Korean Wood Science and Technology
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• v.48 no.6
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• pp.847-860
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• 2020

This study was conducted into combustion characteristics and gases generated by the combustion of charcoal and agglomerated charcoal distributed in the domestic using a combustion chamber based on the average space per crater of a charcoal-grilled restaurant in South Korea. Each of the three types of charcoals and agglomerated wood charcoals was analyzed for fuel and combustion characteristics. In addition, the concentration changes of CO, CO₂, NO_x, and O₂ were measured for 20 minutes depending on ventilation. As a result, CO yield without ventilation was measured in the range of 1390 to 4703 ppm, and CO yield with ventilation decreases about 29.8% to 57.4%. CO₂ yield without ventilation was measured in the range of 1.34% to 2.42%, and CO₂ yield was about 44.1% to 53.6% when the emission was more than about 1.5% at 10 minutes. The NOx yield was divided into two cases where the NO_x yield was continuously increased because of incomplete combustion, emitted ranging from 29 ppm to 47 ppm, and where emission was constant after 1 minute in the range of 9 ppm to 18 ppm. The NO_x yield with ventilation tends to be similar to the without ventilation, and NO_x yield decreases up to 62.5%. Therefore, it could be used for health risk assessment with the simulation of the usage environment of charcoal and agglomerated wood charcoal.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.1
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• pp.48-58
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• 2014

It is very important to investigate air pollutants emissions emitted from open burning in order to control nonpoint sources effectively. In this study, we utilized incineration simulator proposed by U.S EPA and investigated emissions of CO, OC/EC, from household waste and biomass burning to estimate pollutant emissions by illegal incineration of biomass wastes. Emission factor of OC was estimated as 17.1 g/kg for rice strew, 23.5 g/kg for barley, 10.3 g/kg for corn stover, 4.3 g/kg for unseasoned wood, respectively. In case of EC, it was calculated as 1.6 g/kg for rice strew, 4.3 g/kg for barley, 1.4 g/kg for corn stover, 0.6 g/kg for unseasoned wood, respectively. Most of the pollutants emissions were emitted at the stage 1 and 2. In the stage 3, the pollutants concentration decreased gradually. To estimate emissions and build inventory for biomass burning, we need to know accurate activity data. We, therefore, used activity data of both survey results of previous study and statistical data of National Statistical Office. However, we need to perform additional experiments in the future to obtain more accurate activity data for various cases.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.5
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• pp.75-81
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• 2005

An experimental study on homogeneous charge compression ignition combustion with direct fuel injection was conducted using a single cylinder common-rail diesel engine. To improve the homogeneity of fuel-air mixture, the premixed fuel (gasoline) was injected into premixing chamber and the diesel fuel was injected into the combustion chamber as an ignition source for the gasoline premixture. The experimental results show that soot emissions were dramatically reduced with the increase of fuel premixing ratio, however incomplete products such as HC and CO increased with the increase of the premixed ratio. Earlier injection of Dl diesel fuel increased the IMEP with the decrease of HC and CO concentrations.

• Clean Technology
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• v.25 no.4
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• pp.316-323
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• 2019

In order to enhance combustion efficiency and reduce atmosphere pollutants, it is essential to measure carbon monoxide (CO) concentration precisely in combustion exhaust. CO is the important gas species regarding pollutant emission and incomplete combustion because it can trade off with NOx and increase rapidly when incomplete combustion occurs. In the case of a steel annealing system, CO is generated intentionally to maintain the deoxidation atmosphere. However, it is difficult to measure the CO concentration in a combustion environment in real-time, because of unsteady combustion reactions and harsh environment. Tunable Diode Laser Absorption Spectroscopy (TDLAS), which is an optical measurement method, is highly attractive for measuring the concentration of certain gas species, temperature, velocity, and pressure in a combustion environment. TDLAS has several advantages such as sensitive, non-invasive, and fast response, and in-situ measurement capability. In this study, a combustion system is designed to control the equivalence ratio. Also, the combustion exhaust gases are produced in a Liquefied Petroleum Gas (LPG)/air flame. Measurement of CO concentration according to the change of equivalence ratio is confirmed through TDLAS method and compared with the simulation based on Voigt function. In order to measure the CO concentration without interference from other combustion products, a near-infrared laser at 4300.6 cm^-1 was selected.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.4
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• pp.26-31
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• 2006

An experimental investigation of an early injection strategy was conducted on a small single cylinder common-rail DI diesel engine to reduce the oxides of nitrogen($NO_x$) emission. The main objectives of this study were to investigate the emissions, performance and combustion characteristics in a diesel engine with early and two-stage injections. The two- stage injection was conducted to reduce the wall-wetting of early injected fuels on the cylinder wall or to promote the ignition of premixed charge. The engine test was performed at conditions of 1500rpm, injection timing ranging from TDC to BTDC $80^{\circ}$. The experimental results show that $NO_x$ emissions were decreased in both cases of early injection and two stage injection compared to the conventional diesel combustion by the near TDC injection. However, soot and products of incomplete products (i.e. HC and CO) are slightly increased. Also, the second injection near TDC promoted the ignition of premixed fuel, therefore, IMEP was increased.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.3
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• pp.315-320
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• 2020

Pellets are manufactured using wood by-products. The combustion efficiency of pellets depends on the pellet manufacturing process, the types of materials mixed while manufacturing and the wood pellet stoves themselves. In this study, we developed a multi-layer combustor to be used in a wood pellet stove, for the purpose of reducing environmental pollution and energy waste due to incomplete combustion. The multi-layer combustor was designed to compensate for the shortcomings of existing combustors. A CAD (Computer Aided Design) model was verified using a 3D printer and a prototype was developed. The combustion experiments were conducted on commercial and proposed combustors using pellets of the same brand, manufacturing date, place and specifications. From the experiments, it was found that the proposed combustor produced the lowest carbon monoxide (CO) emission and highest thermal efficiency.

• 한국연소학회:학술대회논문집
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• 2002.06a
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• pp.85-94
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• 2002

Computational flow dynamics(CFD) has been frequently applied to the waste incinerators to understand the flow performance for various design and operating parameters. Though it needs many simplifications and complicated flow models, the reasonability of its results is not fully evaluated. For example, the inlet condition is calculated from an arbitrarily assumed properties of combustion gas release from the waste bed, since the combustion in the bed is difficult to be predicted. In this study, the computational modeling and calculation procedures of CFD for the grate type waste incinerator were evaluated using comparative simulations. Though the assumption method on the generation of the combustion gas directly affected the temperature and gas species concentrations, the overall flow pattern was dominated by the secondary air jets. The gaseous reaction could be included by assuming the release of the products of incomplete combusion from the bed. However, the reaction effficiency cannot not be directly evaluated from the species concentration, since it is not possible to simulate the actual co-existence of fuel rich or oxygen rich puffs over the bed. In predicting the turbulence, the higher order model, such as Reynolds stress model, gave difference shape of local recirculation zones, but similar results was acquired from the standard $k-{\varepsilon}$ model. Introducing radiation model was required for accurate temperature prediction, but it also caused heat imbalance due to the fixed temperature of the inlet, i.e. the waste bed. Thus, the computational modeling procedures on incinerators and the analysis of the predicted results should be progressed carefully. Though not validated experimentally, current simulation method is capable of comparative evaluation on the flow-related parameters such as the furnace shape and secondary air injection using identical inlet conditions. Quantitative analysis using measures of the residence time and mixing is essential to compare the flow performance efficiently.

• Korean Chemical Engineering Research
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• v.40 no.6
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• pp.757-762
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• 2002

The interest of incineration, which is one of the effective methods for municipal waste disposal, has gradually increased because the incineration could reduce the volume and weight of the waste, and produce useful energy from the waste. This study has developed the 3-dimensional numerical model, and applied for the investigation of combustion characteristics and optimized operating conditions in MSW incinerator in Gwangju. The model developed in this study has been verified through the comparison between the predicted and the measured temperature in combustion chamber which is operating. By predictive results, the Sangmoo incinerator has a good characteristics of combustion efficiency and a low emission by the second burning in the main flame zone, even though after burning zone produces incomplete products by which primary air is introduced not enough.