• 에너지공학
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• 제6권1호
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• pp.96-103
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• 1997

0.5~1.0톤/일 용량의 BSU급 분류층 가스화기에서 중국산 Datong탄에 대한 석탄가스화 특성실험을 하였다. 가스화기의 반응온도는 1300~155$0^{\circ}C$를 유지하였으며, 실험에 사용된 슬러리농도는 62.5wt% ($H_2O$/Coal=0.6)였다. 산소 및 슬러리는 버너에 주입되기전 예일을 실시하였으며 $O_2$/Coal의 공급비는 0.8~l.2를 유지하였다. 또한 슬러리의 점도를 낮추고 유동성을 향상시키기 위하여 첨가제로서 CWM 1002와 NaOH를 각각 0.3%와 0.05% 추가하였다. 석탄가스화 실험에서 측정된 생성기체는 주로 수소, 일산화탄소 및 이산화탄소로 구성되어 있으며 미량의 메탄도 생성되었다. 생성된 가스는 반응온도가 증가함에 따라 H$_2$와 CO의 생성량은 증가하는 반면 $CO_2$의 양은 감소하였다. 산소의 공급량이 증가함에 따라 $CO_2$의 생성량은 지속적으로 증가하고 CO 및 H$_2$의 생성량은 $O_2$/Coal의 비가 약 0.9에서 최대치를 나타낸 후 감소하였으며, 생성가스 발열량은 1700~2400 kcal/N㎥을 나타내었다.

• 공업화학
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• 제18권5호
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• pp.495-500
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• 2007

석탄가스화기의 내벽은 내화물로 구성되어 있다. 내화물의 침식은 가스화기 내화물의 수명 및 교체시기에 영향을 미치는 중요한 인자이다. 본 논문에서는 슬래그와의 반응에 의한 내화재의 미세구조의 변화를 침식화합물의 형성에 가장 큰 영향을 미치는 산화철 농도의 함수로 조사하였다. 산화철 농도가 낮은 KIDECO 탄 슬래그에 산화철을 첨가하여 정적 침식실험을 수행한 후 $(Fe,Cr)_3O_4$의 형성과 침투 슬래그에서의 Fe의 고갈 깊이를 측정하였다. 그리고 FactSage를 이용한 평형계산을 통하여 chromite 형성조건을 조사하고 실험 결과와 비교하였다. 고정된 온도인 $1550^{\circ}C$에서 약 10%의 산화철을 포함한 KIDECO 슬래그에서는 $(Fe,Cr)_3O_4$의 형성이 관찰되지 않았으나 산화철의 함량이 증가될수록 $(Fe,Cr)_3O_4$ 형성이 관찰되었으며, 경계면의 $(Fe,Cr)_3O_4$ 층의 두께가 증가하였고, 산화철의 고갈 깊이도 증가하였다. 또한 산화철의 양이 많아질수록 화학적 침식이 증가하면서 슬래그와 내화물의 경계가 모호해지는 것을 확인하였다. 슬래그-내화재 계의 평형계산은 슬래그의 산화철 농도가 증가할수록 가스화기 조업온도에서 chromite 형성 가능성이 높아짐을 보여주었다, 또한 내화물이 슬래그에 용해된 경우와 같이 $Cr_2O_3$가 낮은 농도로 존재할 때 chromite 형성이 가장 유리하였고, 산화철의 농도가 20% 이하에서는 슬래그와 내화물이 같은 양으로 존재하는 경우가 chromite 형성에 가장 불리하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.137.2-137.2
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• 2010

With current real economic growth of more than 10% per year, the Chinese energy consumption is rapidly increasing. Coal supply consists of the vast majority of China's total energy consumption requirements in 2008. China, the largest energy consumer, is expected to be heavily dependent on coal for future power generation, too (IEA,2009). A growing concern on global warming, on the other hand, drives Chinese government to declare her commitment to the reduction of CO2 emission by 2020. In this paper, China's energy market is examined for the current and future primary energy mix. Coal is found to be the biggest part accounting for 68.7% of total primary energy consumption while coal-fired power accounts for over 80% of the total power generation. The importance of Clean Coal Technology is being discussed based on the findings of the importance of coal in China's economy and its sustainable development. Among the technologies involved, a brief investigation of IGCC(Integrated Gasification Combined Cycle) technology with a review on current IGCC projects in China are provided from the perspective of environmental benefits. Studies on regional Chinese power market is also conducted. It is found that the regulated power tariff in electricity system makes the power suppliers suffer from financial loss and changes in the electricity price system is under serious consideration by Chinese government. Even though Chinese power market system causes difficulties of commercialization for IGCC technology, the potential benefits will be high due to China's huge requirements of power generating capacity and its heavy reliance on coal if the electricity price system can be changed smoothly.

• 한국물환경학회지
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• 제26권5호
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• pp.754-760
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• 2010

This study was carried out not only to evaluate optimal operating condition to increase biogas production, but also to estimate feasibility of renewable energy from anaerobic digester of sewage sludge. Semi- continuous Fed and Mixed Reactors (SCFMRs) were operated in various condition to quantify the reactor variables. The result of SCFMR operation showed that the biogas productivity and total volatile solids (TVS) removal of total solids (TS) 4% reactor at hydraulic retention time (HRT) 20 days with Organic Loading Rate (OLR) of $1.45kg/m^3-d$ were $0.39m^3/m^3-d$ and 26.7%, respectively which was two times higher than that of TS 2.5% reactor. Consequently the daily biogas production of $20,000m^3$ would be possible from the total volume of $52,000m^3$ of anaerobic digesters of the municipal wastewater treatment plant in D city. In feasibility study for the Biogas utilization, combined heat and power system (CHP) and CNG gasification were examined. In case of CHP, the withdrawal period of capital cost for gas-engine (GE) and micro gas-turbine (MGT) were 7.7 years and 9.1 years respectively. biogas utilization as Clean Natural Gas (CNG) shows lower capital cost and higher profit than that of CHP system. CNG gasificaion after biogas purification is likely the best alternative for Biogas utilization which have more economic potential than CHP system. The withdrawal period of capital cost appeared to be 2.3 years.

• 한국수소및신에너지학회논문집
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• 제22권1호
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• pp.118-127
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• 2011

An IGCC was evaluated as one of the next generation technologies that would be able to substitute for coal-fired power plants. According to "The 4th Basic Plan of Long-term Electricity Supply & Demand" which is developed by the Electricity Business Acts, the first IGCC will be operated at 2015. Like other new and renewable energy such as solar PV, Fuel cell, The IGCC is considered as non-competitive generation technology because it is not maturity technology. Before the commercial operation of an IGCC in our electricity market, its economic feasibility under the Korean electricity market, which is cost-based trading system, is studied to find out institutional support system. The results of feasibility summarized that under the current electricity trading system, if the IGCC is considered like a conventional plant such as nuclear or coal-fired power plants, it will not be expected that its investment will be recouped within life-time. The reason is that the availability of an IGCC will plummet since 2016 when several nuclear and coal-fired power plants will be constructed additionally. To ensure the reasonable return on investment (NPV>0 IRR>Discount rate), the availability of IGCC should be higher than 77%. To do so, the current electricity trading system is amended that the IGCC generator must be considered as renewable generators to set up Price Setting Schedule and it should be considered as pick load generators, not Genco's coal fired-generators, in the Settlement Payment.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.132.2-132.2
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• 2010

기후변화협약 등으로 인하여 기존 화력발전기술보다 효율이 높고 온실가스 발생을 줄일 수 있는 고효율 청정석탄 이용기술에 대한 사회적 요구가 높아짐에 따라 석탄 가스화와 관련된 기술 개발이 확대되고 있다. 석탄을 가스화하면 CO와 $H_2$가 주성분으로 구성된 합성가스를 얻을 수 있는데, 이를 청정가스연료로 사용하기 위해서는 합성가스에 포함된 분진의 제거가 필수적이다. 대부분의 석탄가스화 공정에서는 캔들형 필터를 사용한 여과식 집진시스템을 적용하여 합성가스에 포함된 분진을 제거하고 있다. 본 연구에서도 Pilot급 석탄 가스화기에서 제조된 합성가스에 포함된 분진 제거를 위하여 고온/고압 집진시스템을 구축하였으며, 다양한 운전조건과 필터 종류에 따른 집진시스템의 운전특성 파악을 수행하였다. 연구결과 석탄 합성가스를 안정적으로 정제 하기위한 집진시스템의 중요한 운전 기준과 방법을 도출할 수 있었으며, 이렇게 도출된 운전 기준과 방법은 용량이 증대된 집진시스템의 연속운전을 진행하여 향후 실증할 예정이다.

• 한국해양공학회지
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• 제24권5호
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• pp.31-38
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• 2010

The Floating storage and re-gasification unit (FSRU), which has large cargo storage tanks, is a floating liquefied natural gas (LNG) import terminal. The sloshing motion in tanks that are partially filled with LNG can cause impact pressure on the containment system and affect the global motion of the FSRU. Therefore, the accurate prediction of sloshing motion has been a significant issue in the offshore gas production industry. In this paper, a particle method based on the moving particle semi-implicit (MPS) method proposed by Koshizuka and Oka (1996) has been modified to predict sloshing motion accurately in a rectangular tank with the filling ratio of water. The simulation results, including the violent sloshing of the fluid, were validated by comparison with the original MPS method.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.840-843
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• 2009

폐자동차의 최종처분 과정에서 발생하는 자동차 파쇄 폐기물(Automobile Shredder Dust)은 대부분이 고분자 화합물로 높은 발열량을 가지고 있다. 또한 할로겐족 원소가 포함된 난연성 고분자류가 많아 다이옥신의 생성 우려가 높은 고분자류와 다이옥신 생성의 촉매 역할을 할 수 있는 금속성분이 많이 함유되어 있어 가스화용융시스템에 적용하여 처리하기에 매우 적합한 폐기물이다. 본 연구에서는 ASR의 가스화 용융 시설에서 고농도 CO를 함유한 합성가스를 수성가스전환반응(Water Gas Shift reaction, WGS)을 이용하여 수소의 수율을 높이는 기술을 제시하였다. 가스화 용융 설비에서 배출되는 합성가스 조성을 기준으로 적합한 고정층 WGS 반응기를 설계하고, 고온 촉매(KATALCO 71-5M)와 저온 촉매(KATALCO 83-3X)를 사용하여 실험하였다. 수성가스 반응 후의 가스 조성은 온도가 상승할수록 일산화탄소가 줄어들고 이에 따라 수소와 이산화탄소 발생량이 증가 되어 고온 촉매를 사용했을 경우 일산화탄소 전환율 ($1-CO_{out}/CO_{in}$)은 55.6에서 95.8%까지 상승하였다. 동일한 온도조건에서는 촉매에 관계없이 $CO/H_2$가 감소할수록 전환율도 감소하는 경향을 보였지만 동일한 합성가스 조성에서 일산화탄소 전환율을 비교하면 저온 촉매가 고온 촉매보다 매우 우수함을 알 수 있었다.

• 한국연소학회지
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• 제15권1호
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• pp.43-49
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• 2010

Co-combustion of syngas in an existing boiler can be one of the options for replacing conventional fossil fuel with alternative fuels such as waste and biomass. This study is aimed to investigate effects of syngas cocombustion on combustion characteristics and boiler efficiency. An experimental study was performed for a pilot-scale furnace with 4 oil burners. Tests were conducted with mixture-gas as a co-combustion fuel and heavy oil as a main fuel. The mixture-gas was composed of 15% CO, 7% $H_2$, 3% $CH_4$ and 75% $N_2$ for simulating syngas from air-blown gasification. And LHV of the mixture-gas was 890 kcal/$Nm^3$. Temperature distribution in the furnace and flue gas composition were measured for various heat replacement ratio by the mixture gas. Heat loss through the wall was also carried out through heat & mass balance calculation, in order to obtain informations related to boiler efficiency. Experimental results show that similar temperature distribution and flue gas composition can be obtained for the range of 0~20% heat replacement by syngas. NOx concentration is slightly decreased for higher heat replacement by the syngas because fuel NOx is decreased in the case. Meanwhile, heat loss is a bit decreased for higher heat replacement by the syngas, which implies that boiler efficiency can be a bit decreased when syngas co-combustion is applied to a boiler.

• The Korean Journal of Ceramics
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• 제1권2호
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• pp.86-90
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• 1995

Theoretical predictions for thermodynamically stable phases which formed when alkali(sodium and potassium) vapors reacted with alumina-chromia refractories under coal gasifying atmosphere were confirmed experimentally using a laboratory-scale coal gasifying reaction system and a commercial alumina-chromia refractory using SEM, XRD, and EDAX. Alkali concentration profiles in the refractory as a function of time were also determined. The results showed that the compounds that formed were $X_2O{\cdot}Al_2O_3, X_2O{\cdot}Cr_2O_3, X_2O{\cdot}5Al_2O_3, X_2O{\cdot}7Al_2O_3, X_2O{\cdot}11Al_2O_3(X=Na^+ \;or\; K^+)$, depending upon the alkali concentration and time of exposure at high temperatures. The presence of sulfur in gasifying atmospheres did not appear to affect the alkali reaction produces. Alkali pentration into the alumina-chromia refractory was deep and the formation of the $Na_2O{\cdot}Al_2O_3/K_2O{\cdot}Al_2O_3$ compunds resulted in the serious deformation of the refractory due to the large volume expansion at the reaction surface. The hot face of the alumina-chromia refractory in service under an alkali environment is prone to failure by alkali attack.