• Journal of the Korean Institute of Gas
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• v.26 no.4
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• pp.1-8
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• 2022

DME, a clean fuel that is being studied as an alternative fuel for diesel engines, can reduce exhaust gas, which is the one of the crucial problems of diesel engines, and has a very high cetane number and high oxygen content. DME is a fuel has properties similar with LPG and can use the infrastructure of LPG. In this study, The target was to build a database of basic data on the mass flow rate discharged for the performance evaluation of the plunger-type high pressure pump. In this study, the mass flow rate of the DME plunger type high pressure pump was analyzed by changing the common rail pressure and the motor rotation speed. The experimental conditions were the common rail pressure was changed from 300 to 500 bar and the motor rotation speed was changed from 300 to 1000 rpm. In addition, basic mass flow data were constructed to high-pressure pumps for DME. As a result of the experiment, in both cases the mass flow rate was increased.

• Clean Technology
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• v.16 no.4
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• pp.297-303
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• 2010

Effect of interconnect structure on the cell performance in anode-supported tubular solid oxide fuel cell (SOFC) has been investigated in this study, employing the Fluent CFD solver. For the robust and reliable theoretical analysis corroborating experimental results, it is of great importance to elucidate the role of interconnect which is electrically connected with electrodes on the cell characteristics. From the fact that the thin interconnect provides the enhanced cell performance, it is revealed that the interconnect thickness is a key parameter that is able to effectively control the ohmic resistance. Under the constant thickness condition, the cell performance does not considerably change with the variation of interconnect width. This is because the current passage along with circumferential direction is not effectively altered by the change of interconnect width in tubular SOFC system.

• Clean Technology
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• v.26 no.4
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• pp.239-250
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• 2020

Biomass is an abundant renewable energy resource that can replace fossil fuels for the reduction of greenhouse gas (GHG). Indonesia has a large number of cheap biomass feedstocks, such as reforestation (waste wood) and palm residues (empty fruit bunch or EFB). In general, raw biomass contains more than 20% moisture and lacks calorific value, energy density, grindability, and combustion efficiency. Those properties are not acceptable fuel attributes as the conditions currently stand. Recently, torrefaction facilities, especially in European countries, have been built to upgrade raw biomass to solid fuel with high quality. In Korea, there is no significant market for torrefied solid fuel (co-firing) made of biomass residues, and only the wood pellet market presently thrives (~ 2 million ton yr-1). However, increasing demand for an upgraded solid fuel exists. In Indonesia, torrefied woody residues as co-firing fuel are economically feasible under the governmental promotion of renewable energy such as in feed-in-tariff (FIT). EFB, one of the chief palm residues, could replace coal in cement kiln when the emission trading system (ETS) and clean development mechanism (CDM) system are implemented. However, technical issues such as slagging (alkali metal) and corrosion (chlorine) should be addressed to utilize torrefied EFB at a pulverized coal boiler.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.2
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• pp.59-72
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• 2009

In order to utilize sewage sludge as a heat source of energy, it goes without saying that the fuel should be clean and pose no threat to the environment. As a consequent, it should not contain even minute quantities of heavy metals / impurities. The SOCA (Sludge-Oil-Coal- Agglomerates) fuel can meet all these requirements. SOCA being a solid fuel can be gasified for the production of clean energy. Wet catalytic gasification is the most appropriate process for SOCA containing nearly 60% water. It is important to note that the SOCA thus obtained inherits ca. 40~50% of sulfur from the coal used. It can poison the catalyst during catalytic gasification process. Consequently, it becomes important to choose a proper catalyst for the gasification. Calcium was found to be ideal choice as a catalyst for the gasification of SOCA. The optimal gasification was performed at $850^{\circ}C$ with water vapor. The role of fuel-N is of utmost importance in the gasification of SOCA. The gasification should be controlled to reduce the production of HCN to a minimum and enhance its conversion to $N_2$ and/or $NH_3$.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2009.10a
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• pp.371-372
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• 2009

• The Magazine for Energy Service Companies
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• s.42
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• pp.22-25
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• 2006

기후변화 완화를 위한 선진국과 개도국 간 온실가스 감축협력사업인 `청정개발체제(CDM)사업'이 전 세계적으로 활발히 진행되고 있따. 우리나라도 이에 능동적으로 대응하기 위해 CDM 사업에 박차를 가하기 시작했다. 최근 한국지역난방공사의 연료전환사업과 수자원공사의 소수력발전, 동서발전의 태양광발전 설비가 CDM사업인증을 받아 온실가스 감축협력 사업에 앞장서고 있어 그곳을 찾아가봤다.

• Journal of Energy Engineering
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• v.24 no.4
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• pp.33-41
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• 2015

Dimethyl ether (DME) can be used as a clean diesel alternative fuel due to the high cetane number and low emission, it can also be applied to automotive fuel as a blended liquefied petroleum gas (LPG) because physical properties are similar to those of LPG. In this study, feasibility test of LPG vehicle using blended DME-LPG fuel was investigated. Three types of fuel supply such as LPLi (Liquid phase LPG injection), LPGi (Liquid phase gas injection) and mixer type were selected to consider the LPG fuel-injection system. The performance characteristics of LPG vehicle were examined by using LPG and blended DME-LPG fuel in order to compare the exhaust emissions (CO, THC, $NO_X$) and fuel economy. The emissions and fuel economy of DME-LPG blend fuel were comparable to those of LPG with increasing driving distance.

• Korean Chemical Engineering Research
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• v.49 no.6
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• pp.688-696
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• 2011

Hydrogen is one of the few long-term sustainable clean energy carriers, emitting only water as by-products during its combustion or oxidation. The use of fossil fuels to produce hydrogen makes large amount of carbon dioxide (>7 kg $CO_{2}$/kg $H_{2}$) during the reforming processes. Hydrogen production can be environmentally benign only if the energy and the resource to make hydrogen is sustainable and renewable. Biomass is an attractive alternative to fossil fuels for carbon dioxide because of the hydrogen can be produced by conversion of the biomass and the carbon dioxide formed during hydrogen production is consumed by biomass generation process. Hydrogen production using solar energy also attracts great attention because of the potential to use abundance natural energy and water.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.47-50
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• 2006

현재의 화석연료-기반 사회에서는 지구 온난화와 고유가 추세가 야기하는 경제적 피해, 에너지 안보우려, 세계 평화 위협 등에 자주 노출되고 있는 실정이다. 세계 각국은 이러한 화석연료 에너지원을 대체하는 환경-청정하고 기술-신뢰할 수 있으며 경제-감당할 수 있는 에너지 공급원인 수소를 기반으로 하는 미래의 수소-기반 사회로의 진입에 노력하고 있다. 특히, 청정한 에너지 운반체인 수소의 생산 기술 상업화가 더욱 더 절실히 요구되고 있다. 이 예비 연구에서는 이산화탄소 포획/저장 기술과 결합된 다양한 수소 생산 기술의 정량적인 예비 비교 평가가 수행되었다. 예비적인 비교 평가 기준으로 1) 이산화탄소 배출량: 2) 에너지 이용률; 3) 토지 점유율: 4) 수소 생산비용 등이 고려되었다. 이러한 기준에 따라 수소 생산 기술 가운데 네 가지 예비 기술 대안인 1) 원자력: 2) LNG; 3) 석탄: 4) 태양광 등이 비교되었다. 대안 기술의 비교 평가 체제로 계층 망형 구조-기반 되먹임 모델이 개발되었다. 이러한 수소생산 기술의 우선순위 선정 결과는 개별 대안 기술의 상대적인 장단점 및 기술적인 갭을 정량적으로 인식하는 데에 활용될 수 있다. 그러므로 이 예비 연구는 수소 생산 기술 연구자나 수소 경제 기획자한테 뿐만 아니라 이산화탄소 포획/저장 기술 개발자한테 도움이 되리라 본다.

• Clean Technology
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• v.26 no.4
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• pp.329-335
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• 2020

Methanol synthesized from renewable hydrogen and captured CO2 has recently attracted great interest as a sustainable energy carrier for large-scale renewable energy storage. In this study, molten carbonate fuel cell's performance was investigated with the direct conversion of methanol into syngas inside the anode chamber of the cell. The internal reforming of methanol may significantly improve system efficiency since the heat generated from the electrochemical reaction can be used directly for the endothermic reforming reaction. The porous Ni-10 wt%Cr anode was sufficient for the methanol steam reforming reaction under the fuel cell operating condition. The direct supply of methanol into the anode chamber resulted in somewhat lower cell performance, especially at high current density. Recycling of the product gas into the anode gas inlet significantly improved the cell performance. The analysis based on material balance revealed that, with increasing current density and gas recycling ratio, the methanol steam reforming reaction rate likewise increased. A methanol conversion more significant than 90% was achieved with gas recycling. The results showed the feasibility of electricity and syngas co-production using the molten carbonate fuel cell. Further research is needed to optimize the fuel cell operating conditions for simultaneous production of electricity and syngas, considering both material and energy balances in the fuel cell.