• 공업화학
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• 제22권5호
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• pp.566-574
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• 2011

석탄가스화기는 석탄가스화복합발전과 석탄간접액화 공정에서 고효율을 얻기 위한 중요한 설비 중 하나이다. 현재 여러 종류의 석탄가스화기가 성공적으로 사용되고 있지만, 간단하면서도 신뢰도를 높일 수 있는 다양한 설계 변경이 가능하다. 건식 분류층 가스화기 4종류의 형태를 제시하고 이들을 체류시간, 가스화기 출구 합성가스의 온도, 합성가스 조성을 중점으로 비교하였다. 설계개념이 적정한지를 우선 파악하고자 반응을 배제한(cold-flow) CFD 해석을 먼저 수행하였고, 실제 가스화기 조건을 반영한 화학반응이 고려된(hot-flow) 해석을 수행하여 비교하였다. 가스화기 설계에 CFD를 적용하는 데는 슬랙의 거동과 슬랙탭 설계 등 측면에서 제한적이기는 하지만, 다양한 설계개념 중에서 가능성이 높은 가스화기 형태의 범위를 좁히는 데 매우 유용하게 사용될 수 있다.

• 한국수소및신에너지학회논문집
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• 제16권3호
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• pp.209-218
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• 2005

To find a suitable metal component in oxygen carrier particles for chemical-looping hydrogen generation system(CLH), oxygen transfer capacities of metal components were compared and Ni has been selected as the best metal component. The proper operating conditions to achieve high hydrogen generation rate have been investigated based on the chemical-equilibrium composition analysis for water splitting reactor. Moreover, suitable compositions of syngas from gasifier of heavy residue to achieve high energy efficiency have been investigated by calculation of heat of reaction. Based on the selected operating conditions, the best configuration of two interconnected fluidized beds system for the chemical-looping hydrogen generator has been investigated as well.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.368-371
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• 2008

The optimal operation condition of gasifier is one of the most important parameters to increase efficiency and reliability in IGCC plant. Also the prediction of the syngas composition and quantity must be predicted to carry out process design of the gasification plant. However, the gasifier process licensor are protective with information on process design and optimal gasifier design conditions. So, the most of process studies in the engineering company for gasification plant have carried out to look for key parameters and optimal design conditions using several prediction methods. In this paper, we present the estimated preliminary optimal operation condition of the 300MW Demonstration Entrain Flow Gasifier using Aspen Plus. The gasifier operation temperature considering slag flow was predicted by FactSage software and Annen Model.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2007년도 제34회 KOSCO SYMPOSIUM 논문집
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• pp.63-68
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• 2007

An experimental study was carried out to investigate gasification process of wood sawdust in the 1-dimensional downdraft fixed bed gasifier. The preheated air which was used oxidizer and steam were used as a gasifying agent. The downdraft fixed bed gasifier obtains more amount of hydrogen and methane by increasing residence time of supplied air. The operating parameters, the supplied air temperature and steam were used. The oxidizer temperature was varied from 500K to 620K and vapor was added. The gasification process was monitored by measuring temperature at three position near the biomass using R-type thermocouples and the syngas composition was analyzed by gas chromatograph. We get the sample gas at the end of gasifier and it was eonugh time to finishing the chemical reaction. Finally, the amount of hydrogen and methane were increased widely as increasing the oxidizer temperature and adding steam.

• Advances in Energy Research
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• 제3권3호
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• pp.181-194
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• 2015

In this work, an experimental study of the gasification on wood was carried out in downdraft type fixed bed Gasifier attached with 10 kW duel fuel diesel engine. The main objective of the study was to use wood as the biomass fuel for downdraft Gasifier and to evaluate the operating parameter of gasifier unit to predict its performance in terms of gas yield and cold gas efficiency. The influence of different biomass on fuel consumption rate, gas yield and cold gas efficiency was studied. Composition of producer gas was also detected for measuring the lower heating value of producer gas to select the feed stock so that optimum performance in the existing gasifier unit can be achieved. Under the experimental conditions, Lower heating value, of producer gas, cold gas efficiency and gas yields, using wood as a feed stock, are $4.85MJ/m^3$, 46.57% and $0.519m^3/kg$.

• 청정기술
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• 제28권1호
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• pp.1-8
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• 2022

미활용 저급자원인 석유코크스를 대상으로 고순도의 수소 생산을 위한 수성가스전이반응에 적용가능성을 확인하기 위하여 Cu/ZnO/MgO/Al₂O₃ (CZMA) 촉매를 공침법을 사용하여 제조하였다. 제조된 촉매는 BET, H₂-TPR을 사용하여 분석되었다. 촉매의 반응성 테스트는 고농도의 CO를 포함하는 합성가스로부터 단일 Low Temperature Shift 반응을 거치는 경우와 High Temperature Shift 반응을 거친 후 스팀의 응축 없이 즉시 LTS 반응을 거치는 두 가지의 경우를 비교 및 분석하였다. 두 조건에서 steam/CO 비, 유량 및 유속, 온도에 따른 반응특성을 확인하였다. 전환된 저농도의 CO와 스팀이 응축 없이 LTS로 즉시 주입되는 경우 많은 양의 스팀이 존재함에도 불구하고 대부분의 조건에서 다소 낮은 CO 전환율을 나타냈다. 또한 steam/CO비, 온도 및 유속에 대한 영향이 크게 나타나 최적의 조업조건을 결정하기에 추가적인 분석이 요구되었다. 반면, 고농도의 CO 기체를 포함하는 조건에서는 탄소침적 또는 촉매의 활성 저하가 나타나지 않았으며 대부분의 조건에서 높은 CO 전환율을 나타내었다. 결론적으로 Cu/ZnO/MgO/Al₂O₃ 촉매를 적용하여 고농도의 CO를 포함하는 합성가스 조성에서 적절한 조업조건을 적용시키면 단일 LTS 반응을 적용해도 고농도의 CO를 CO₂로 충분히 전환 가능함을 확인하였다.

• 한국분무공학회지
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• 제23권3호
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• pp.114-121
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• 2018

FT process is a technology of chemical reactions that converts a mixture of carbon monoxide and hydrogen into liquid hydrocarbons. During the FT process unreacted gas, known as Off-gas which has low-calorie, is discharged. In this study, we developed an engine that utilize simulated Off-gas, and studied the characteristics of the engine. The off-gas composition is assumed to be $H_2$ 70%, CO 15%, $CO_2$ 15% respectively. Under stoichiometric air-fuel ratio, the experiment was conducted at WOT and IMEP 0.3 Mpa changing compression ratio. Ignition timing was applied with MBT timing. Maximum indicated thermal efficiency 37% was achieved at compression ratio 15 under WOT. CO, $CO_2$ and $NO_x$ were influenced by changing compression ratio, and CO emission was satisfied with the US Tier 4 standard for nonroad engine over the entire experimental conditions.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.158.2-158.2
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• 2011

DME is acronym of dimethyl ether, which is spotlighted as an ideal fuel to produce hydrogen due to its high hydrogen/carbon ratio, high energy density and easiness to carry. In this research, we calculated thermodynamic hydrogen (or syngas) yield from DME autothermal reforming and compared to other fuels. The reforming efficiency was about 80% above $700^{\circ}C$. Lower OCR has higher reforming efficiency but, it requires additional heat supply since the reactions are endothermic. SCR has no significant effect on the reforming efficiency. The optimized condition is $700^{\circ}C$, SCR 1.5, OCR 0.45 without additional heat supply. Comparing to other commercial gaseous fuels (methane and propane), DME has higher selectivity of $H_2O$ and $CO_2$ than the others due to the oxygen atom in the molecule. To apply DME autothermal reforming to real system, a proper catalyst is required. Therefore, it is performed the experiment comparing various novel metal catalysts based on CGO. Experiments were performed at calculated condition. The composition of product was measured and reforming efficiency was calculated. The catalysts have similar efficiency at high temperature(${\sim}800^{\circ}C$) but, CGO-Ru has the highest efficiency at low temperature ($600^{\circ}C$).

• 한국수소및신에너지학회논문집
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• 제20권4호
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• pp.337-343
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• 2009

Noncatalytic partial oxidation of methane for producing synthesis gas was studied in a lab-scale experimental apparatus. Partial oxidation developed for high-temperature, fuel-rich combustion and it is exothermic process. but Steam reforming and Caron reforming is highly endothermic process to need much energy. Noncatalytic partial oxidation of methane is affected by temperature and equivalent ratio, so we studied effect about composition of synthesis gas at lab scale reactor. We used electronic heater to control the temperature of reactor. The quality of synthesis gas is improved and reduced heat value to require at Noncatalytic partial oxidation because the reacting temperature is lower at oxy condition.

• 한국수소및신에너지학회논문집
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• 제22권6호
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• pp.913-924
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• 2011

A steady-state analysis has been conducted to predict the behavior of the slag layer in the entrained-flow slagging coal gasifier. The analysis takes into consideration the composition dependent slag properties such as density, viscosity, heat capacity, thermal conductivity, and temperature of critical viscosity. The amount of added flux to the design coal and the variation of syngas temperature inside the gasifier have been adopted as calculation parameters. The predicted results are the local thickness of the molten and the solid slag layers, and the slag viscosity and the velocity distribution across the molten slag layer along the gasifier wall near the slag tap.