• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.153-156
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• 2008

MILD combustion has been successfully applied to gaseous fuels and few commercial systems are now in operation. Extending MILD combustion applicability to solid fuel of sawdust is the focus of the present work. The MILD combustion furnace at the University of Adelaide in Australia was used in this study. A measurement of $O_2$ and CO emissions have been carried out in parallel with consideration of NOx emission and compared in each modes of conventional natural gas combustion, natural gas MILD combustion, NOx emission in natural gas MILD combustion mode can be reduced to 20% in comparison with conventional combustion. Emission in cases of air carrying sawdust combustion and $CO_2$ carrying sawdust combustion were also compared. Air and $CO_2$ were sued as a carry gas for the sawdust. It was found that MILD conditions are possible for sawdust particles of less than $355{\mu}m$ without additional air pre-heating. It was also found that when using $CO_2$ as the carry gas the flame inside the furnace was not visible anymore and that NOx emission dropped to less than two folds.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.5
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• pp.79-84
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• 2004

We evaluated the reduction performance of NOx storage catalyst and TWC for lean-burn natural gas engine by the model gas. The method of unsteady state reaction was used to compare with reduction performances of NOx storage catalyst and TWC. It was found that the effective parameter was rich spike duration, temperature of the model gas. In the presence of $CO_2$ and $H_2O$ in the reaction mixture was decreased the NOx reduction performance.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.2
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• pp.16-21
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• 2003

Natural gas is one of the promising alternative fuels because of the abundant deposits and the cleanness of emission gas. It can be used in conventional gasoline engine without major modification. Natural gas has some advantages than gasoline i.e. the high octane number, good mixing condition because of gas and wide inflamable limit. In the present study, a $1.8{\ell}$ conventional gasoline engine is modified for using the CNG as a fuel instead of gasoline. Performance and emission characteristics are compared between gasoline and CNG with 4 cylinder SI Engine which is controlled by programable ECU. Parameters of experimentation are equivalence ratio, spark timing and fuels. We analyzed the combustion characteristics of the engine using the cylinder pressure i.e. ignition delay, combustion duration and cycle variation. As a result, CNG engine shows lower exhaust emissions but brake torque is slightly reduced compared to gasoline engine. Overall combustion duration is longer than that of gasoline because of lower burning speed.

• Journal of the Korean Society of Combustion
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• v.20 no.2
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• pp.36-39
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• 2015

The combustion characteristics of metal fiber burner fueled natural gas with tail gas produced from reforming process were analyzed on the point of flame stability and excess air conditions. Also, it was analyzed the effect of energy efficiency improvement due to decrease the fuel input in reforming system by using residue gases. As a results, it was confirmed that tail gas including hydrogen, CO and $CO_2$ could be directly injected without any change of air control system in natural gas burner and also energy efficiency was increased up to 30% maintained stable combustion.

• Structural Engineering and Mechanics
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• v.84 no.6
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• pp.733-741
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• 2022

The amount of natural gas that is used on a worldwide scale is continuously going up. Natural gas and acidic components, such as hydrogen sulfide and carbon dioxide, cause significant corrosion damage to transmission lines and equipment in various quantities. One of the fundamental processes in natural gas processing is the separation of acid gases, among which the safety and environmental needs due to the high toxicity of hydrogen sulfide and also to prevent wear and corrosion of pipelines and gas transmission and distribution equipment, the necessity of sulfide separation Hydrogen is more essential than carbon dioxide and other compounds. Given this problem's significance, this endeavor aims to extend the lifespan of the transmission lines' pipes for gas and oil. Zinc oxide nanoparticles made from the environmentally friendly source of Allium scabriscapum have been employed to accomplish this crucial purpose. This is a simple, safe and cheap synthesis method compared to other methods, especially chemical methods. The formation of zinc oxide nanoparticles was shown by forming an absorption peak at a wavelength of about 355 nm using a spectrophotometric device and an X-ray diffraction pattern. The size and morphology of synthesized nanoparticles were determined by scanning and transmission electron microscope, and the range of size changes of nanoparticles was determined by dynamic light scattering device.

• Environmental and Resource Economics Review
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• v.17 no.4
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• pp.751-774
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• 2008

In this paper, we examine the institutional prices differences in the electricity and natural gas industries using unbalanced panel data from 1999 to 2001. The changing market structures following deregulation in both markets allow us to examine the institutional prices differences by ownership type, market structure and merger activities. Estimating the reduced form, after controlling both intrinsic characteristic (marginal costs) and external factors (demand), allows us to identify the extent to which specific factors are correlated with the price. Furthermore it allows us to identify systematic institutional price differences in both electricity and natural gas markets. Our estimation results suggest that the private firms in electricity markets are associated with higher prices than public firms after controlling for demand and cost. We further find that dual-product firms in the natural gas industry and the electricity industry are associated with lower rates than single product firms. These results provide a weak evidence of economies of scope in the dual-product firms. Our results finally suggest that merger activities in natural gas markets are associated with higher rates.

• Korean Chemical Engineering Research
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• v.47 no.1
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• pp.65-71
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• 2009

In this study, performance and economic analysis of natural gas/syngas fueled 100 MWth chemical-looping combustion (CLC) combined cycle plant were performed. Net efficiency of both cases was 53~54%, corresponding to previous research. We used Chemical Engineering Plant Cost Index and Guthrie method to evaluate plant cost. For syngas fueled CLC combined cycle plant, the plant cost was higher since lower heating value(LHV) of syngas was lower than that of natural gas and cost of electricity(COE) was also higher since the cost of syngas was higher than that of natural gas. By sensitivity analysis, it was shown that the cost of syngas should be less than 5.3 $/GJ in order to make COE lower than 5.8 ¢/kWh which was COE of natural gas fueled CLC combined cycle plant.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.647-650
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• 2005

Gas hydrates draw great at tent ion recently as a new clean energy resources substituting conventional oil and gas hydrate its presumed huge amount of volume reaching 10 trillion tons of gas and environmentally friendly characteristics. Gas hydrate can contribute to the rapidly increasing consumption of natural gas in Korea and achieve the self support target by 2010 which is $30\%$ of total natural gas demand. This paper shows the importance and benefit of Gas hydrate comparing with new & renewable energy in Korea

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.47-49
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• 2006

The Sea of Okhotsk is the unique area providing the highest methane production rate of the northern hemisphere. The area of focused fluid venting offshore the NE Sakhalin continental slope was investigated during the CHAOS (Hydro-Carbon Hydrate Accumulations in the Okhotsk Sea) expeditions onboard of RV "Akademik Lavrentyev" In 2003, 2005 and 2006. The International Research Project CHAOS (Russia-Korea-Japan) aimed at the study of gas hydrate formation processes associated with the fluid venting in the Sea of Okhotsk. Several new gas hydrate accumulations were discovered during the cruise. Hydrate-associated structures have been named as KOPRI, VNIIOKeangeologia, POI and KIT (the names of cruise participant institutes) Some of hydrate-bearing cores contain big amount of gas hydrates: massive gas hydrate layers (up to 35cm thick) were recovered. The shallowest submarine gas hydrate accumulations in the world (at the depth less then 400m) were discovered during the cruise.

• Journal of the Korean Institute of Gas
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• v.23 no.1
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• pp.1-11
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• 2019

The Korean government has tried to introduce pipeline natural gas from Russia, instead of liquefied natural gas from Middle East Asia since 1990s. While this energy cooperation in North East Asia has been discussed in real politics and academic societies, the previous studies have shown the limits on policy implication because they just suggest necessity and possess the problems of weak theoretical frameworks. Therefore, this study tries to analyze the motivations, conditions, and stages for energy cooperation in this region from the viewpoint of economic integration theory. As a result of analysis, these countries in North East Asia have only one motivation, namely economic interest. On the contrary, they have several conditions including real benefit, complementation in economic structures, and convergence in policy goals. In conclusion, this study suggests that low level cooperation such as preferential trade agreement in the field of natural gas is possible and necessary in North East Asia.