• 한국연소학회지
• /
• 제12권3호
• /
• pp.1-7
• /
• 2007

A combined hydrogen generator of plasma and catalytic reformer was developed, and was applied to stabilize unstable flame of 200,000 Kcal/hr LPG combustor. The role of the plasma reformer was to generate hydrogen in a short period and to heat-up the catalytic reformer during the start-up time. After the start-up period, the catalytic reformer generates hydrogen through steam reforming with oxygen (SRO) reactions. The maximum capacity of the hydrogen generator was enough 100 lpm to stabilize the flame of the present combustor. In order to reduce NOx and CO emissions simultaneously, 1) FGR (Flue Gas Recirculation) technique has been adopted and 2) the hydrogen was added into the fuel supplied to the combustor. Test results showed that the addition of 25% hydrogen and 30% FGR rate lead to simultaneous decrease of CO and NOx emissions. The technique developed in the present study showed good potential to replace $NH_3$ SCR technique, especially in the small-scale combustor applications.

• 청정기술
• /
• 제26권4호
• /
• pp.329-335
• /
• 2020

재생에너지로부터 수전해를 통하여 생산된 수소와 포집된 CO2를 활용하여 메탄올을 합성하는 power-to-methanol 기술이 재생에너지를 대용량으로 저장하는 방안으로 제시되고 있다. 본 연구에서는 메탄올을 수소 및 전력 생산에 활용함에 있어 더욱 효율적인 방법으로 연료전지 내부에서 메탄올 수증기개질 반응이 일어나는 내부개질형 용융탄산염 연료전지에 대해 성능 분석을 실시하였다. 용융탄산염 연료전지의 연료극으로 사용되는 다공성 Ni-10 wt%Cr을 촉매로 메탄올 수증기개질 반응을 수행한 결과 연료전지 운전 조건에서 연료극은 메탄올 수증기개질 반응에 충분한 활성을 나타내었다. 메탄올 수용액을 직접 용융탄산염 연료전지의 연료극으로 공급한 결과 연료전지의 성능은 외부 개질기를 통하여 생산된 개질가스를 공급하는 경우에 비해 다소 성능이 낮게 나타났으며, 메탄올 공급유량이 비교적 낮은 경우 고 전류밀도에서 불안정한 성능을 나타내었다. 연료극으로부터 생성된 가스를 재순환시킴으로써 연료전지의 성능을 향상시킬 수 있었으며, 메탄올 전환율도 90% 이상 얻을 수 있었다. 물질수지를 통하여 연료극에서 일어나는 반응을 분석한 결과 전류밀도 및 가스 재순환 유량이 증가함에 따라 메탄올 수증기개질 반응속도가 증가함을 확인하였다. 이상의 결과로부터 별도의 촉매층을 설치할 필요 없이 연료극 만으로도 용융탄산염 연료전지 내에서 메탄올 수증기개질 반응이 가능하며, 메탄올 내부개질형 용융탄산염 연료전지를 통하여 전력과 합성가스를 동시에 생산할 수 있음을 확인하였다.

• 한국수소및신에너지학회논문집
• /
• 제13권4호
• /
• pp.304-312
• /
• 2002

In this study, the performance of the $5Nm^3/hr$ compact type steam reformer which was developed for application of fuel cell or hydrogen station was evaluated in terms of gas process efficiency. For these purposes, reforming efficiency and total efficiency with system load change were analyzed. The reforming efficiency was calculated from the total molar flow of hydrogen output over total fuel flow input to the reformer and the burner on the higher heating value(HHV). In the case of the total efficiency, recovered heat at the heat recovery exchanger was considered. From the results, it was known that system performance was stable, because methane conversion showed the a slight decline which is about 2% though increasing system load to full. Reforming efficiency was increased from 20% to 58%, respectively as increasing system load from 10% to 90%. It was found that total efficiency was higher then reforming efficiency because of terms of heat recovered. As a results, it was known that total efficiency was increased form 75% to 83% at the 10% and 90% system load, respectively. From these results, it is concluded that compact steam reformer which is composed of stacking plate-type reactors is suitable to on-site hydrogen generator or to fuel cell application because of quick start within 1 hr and good performance.

• 한국분말야금학회:학술대회논문집
• /
• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
• /
• pp.479.1-479.1
• /
• 2006

• 전기화학회지
• /
• 제12권2호
• /
• pp.167-172
• /
• 2009

Direct methanol fuel cells(DMFCs) are receiving significant attention in the portable power source and electric vehicular transportation because of its high energy efficiency as liquid fuel, low cost, and no requirement of fuel reforming process. In this study, we synthesized the Sulfonated poly(ether ether ketone) (SPEEK) to evaluate the possibility of use as a proton exchange membrane for DMFC. And poly(vinylidienedifluoride) (PVDF) was used to increase proton conductivity in SPEEK and simultaneously to prevent methanol transport through the cross linked membrane. Furthermore, in order to improve the electrical composite properties for DMFC applications.

• 한국막학회:학술대회논문집
• /
• 한국막학회 2003년도 The 4th Korea-Italy Workshop
• /
• pp.129-132
• /
• 2003

Silica/SUS composite membranes were prepared for CO removal from products of methanol steam reforming. A support was prepared by coating Ni powder of sub-micron and SiO$_2$ sols of particle size of 500nm and 150nm in turns on a porous stainless steel (SUS) substrate. Silica top layer was coated on the modified support using colloidal sol with nanoparticle. As a result of mixture gas permeation test of silica composite membrane using H$_2$(99%)/CO(1%), CO concentration of 10000 ppm was reduced to under 81 ppm, which is acceptable in PEMFC anode gas specification. Permeation mechanism through the membrane was mainly molecular sieving.

• 한국분말재료학회지
• /
• 제28권3호
• /
• pp.201-207
• /
• 2021

Ni-Cr-Al metal-foam-supported catalysts for steam methane reforming (SMR) are manufactured by applying a catalytic Ni/Al₂O₃ sol-gel coating to powder alloyed metallic foam. The structure, microstructure, mechanical stability, and hydrogen yield efficiency of the obtained catalysts are evaluated. The structural and microstructural characteristics show that the catalyst is well coated on the open-pore Ni-Cr-Al foam without cracks or spallation. The measured compressive yield strengths are 2-3 MPa at room temperature and 1.5-2.2 MPa at 750℃ regardless of sample size. The specimens exhibit a weight loss of up to 9-10% at elevated temperature owing to the spallation of the Ni/Al₂O₃ catalyst. However, the metal-foam-supported catalyst appears to have higher mechanical stability than ceramic pellet catalysts. In SMR simulations tests, a methane conversion ratio of up to 96% is obtained with a high hydrogen yield efficiency of 82%.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2008년도 추계학술대회B
• /
• pp.3125-3130
• /
• 2008

Coal is one of the most abundant and cheapest energy sources in the earth, but its typical combustion product, $CO_2$, is related with serious recent environmental issues such as global warming. The Integrated Coal Gasification Combined Cycle (IGCC) with $CO_2$ sequestration is one of the most promising options to produce electricity using a relatively cheap fuel (coal) with minimum impact on environment. In IGCC power generation systems, some chemical reactions are required to gasify coal to produce syngases such as $H_2$ and CO, which would be burnt in the combustor to produce heat for power generation, with a penalty of additional energy consumption. In this paper, several chemical reactions for the gasification of coal are considered and their characteristics are investigated.

• 한국가스학회지
• /
• 제11권1호
• /
• pp.51-54
• /
• 2007

78개 셀의 전극유효 면적이 $295cm^{2}$인 고분자 전해질 연료전지(PEMFC) 스택의 운전특성과 CO 피독에 대한 영향을 조사하였다. 전류밀도 $325mA/cm^{2}$에서 출력 5.4kW를 6시간 유지시키는 동안 셀들의 전압편차는 2.3%로 매우 안정함을 보였다. 개질과정의 부산물로 생성되는 CO는 PEHFC의 성능에 중요한 영향을 끼치는 스택의 주 오염물질중의 하나이다. 시간에 따른 연속적인 CO 피독 실험(5-20ppm)은 스택의 피독과 재생과정의 route를 알 수 있었다.

• 청정기술
• /
• 제25권1호
• /
• pp.81-90
• /
• 2019

프로페인($C_3H_8$)의 건식 개질($CO_2$ 개질)을 통한 합성 가스($H_2$와 CO 혼합물) 제조를 위해 $Ni-CeO_2/{\gamma}-Al_2O_3$ 촉매가 충진된 유전체 장벽 방전 플라즈마 반응기를 사용하였다. 열 또는 플라즈마에 의해 환원된 $Ni-CeO_2/{\gamma}-Al_2O_3$ 촉매를 사용하여 $C_3H_8/CO_2$ 비율 1/3, 총 유량 $300mL\;min^{-1}$에서 플라즈마-촉매 건식 개질을 수행하였다. 건식 개질에 대한 촉매 활성은 온도범위 $500{\sim}600^{\circ}C$에서 평가되었다. $Ni-CeO_2/{\gamma}-Al_2O_3$ 촉매 제조를 위해 전구물질 수용액(질산니켈, 질산세륨)으로 함침된 ${\gamma}-Al_2O_3$를 공기 분위기에서 소성시킨 후, $H_2/Ar$ 분위기에서 환원시켰다. 촉매 특성 조사에는 X-선 회절분석기(XRD), 투과전자현미경(TEM), 전계 방출 주사전자현미경(FE-SEM), 승온 탈착($H_2-TPD$, $CO_2-TPD$) 및 라만 분광기가 이용되었다. 열로 환원된 촉매와 비교하면 플라즈마 방전하에서 환원된 $Ni-CeO_2/{\gamma}-Al_2O_3$ 촉매가 개질 반응을 통한 합성 가스 생산에서 보다 우수한 촉매 활성을 나타내었다. 또한, 플라즈마로 환원된 $Ni-CeO_2/{\gamma}-Al_2O_3$가 개질 반응의 문제점인 탄소퇴적 관점에서 장기 촉매 안정성을 보여주었다.