산업분야 CO₂ 포집기술의 현황 및 전망

류호정 한국공업화학회 2022 한국공업화학회 연구논문 초록집 Vol.2022 No.1

매체순환식 가스연소기 적용을 위한 Ni계 및 NiO계 산소공여입자의 반응특성

류호정,배달희,조성호,진경태 한국화학공학회 2004 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.42 No.1

매체순환식 가스연소기에 적용하기 위한 최적의 산소공여입자를 결정하기 위해 금속산화물(NiO)의 함량 변화에 따라 네 가지 (NiO 26, 44, 58, 78wt%)의 산소공여입자를 제조하여 열중량 분석기에서 환원반응특성을 측정 및 비교하였다. 제조된 입자들 중에서 NiO 약 60wt%인 입자가 산소전달능력 및 반응속도 면에서 다른 입자들에 비해 우수한 성능을 나타내었다. 산소공여입자의 제조과정에서 금속산화물 형태의 영향을 살펴보기 위해 금속산화물의 출발물질로 Ni과 NiO를 사용하여 NiO 함량이 동일한(약 60%) 두 종류의 입자를 제조하였으며 열중량 분석기와 고정층 반응기를 이용하여 반응속도, 재생성, 환원반응 유지시간 및 CO_(2) 선택도 등을 측정 및 고찰하였다. 금속산화물의 출발물질로 NiO를 사용한 입자가 Ni을 사용한 입자에 비해 반복 실험시에 정상반응조건에 빨리 도달하였고 반응속도와 CO_(2) 선택도가 높았으며 환원반응 유지시간인 길게 나타났다. 실험결과에 의해 본 연구에서 고려한 산소공여입자 중에서 금속산화물의 출발물질로 NiO를 사용한 NiO 함량이 60wt%인 입자를 최적의 산소공여입자로 선정하였다. To find a suitable oxygen carrier particle for chemical-looping combustor, four kinds of particles (NiO 26, 44, 58, 78wt%) were prepared and the reactivity of the reduction was measured and investigated by a thermo-gravimetrical analyzer. From the viewpoint of oxygen transfer capacity and reaction rate, the particle containing 60wt% of NiO showed better performance than the other particles. Also, we have prepared two kinds of oxygen carrier particles to investigate the effect of the starting material for a metal oxide component(i.e., Ni based and NiO based particles, where the weight percents of both samples were set at 60wt% as NiO). The reaction rate, regenerative ability, duration of the reduction, and CO₂ selectivity were easured and investigated by a thermo-gravimetrical analyzer and a fixed bed reactor. The results obtained here indicated that the NiO based oxygen carrier particle containing 60wt% of NiO showed better regenerative ability, reaction rate, CO₂ selectivity, and duration of the reduction, compared with the other particles, therefore we selected this particle as an optimum oxygen carrier particle.

회수증진 수성가스화 시스템의 공정구성 및 조업조건 선정

류호정 한국수소및신에너지학회 2009 한국수소 및 신에너지학회논문집 Vol.20 No.2

To check feasibility of SEWGS(Sorption Enhanced Water Gas Shift) system, conceptual design and sensitivity analysis of operating variables have been investigated based on a design program of two- interconnected fluidized bed. Based on the conceptual design results, the optimum configuration for SEWGS was considered. Among three configurations, bubbling beds system was selected as the best configuration. Process design results indicate that the SEWGS system is compact and feasible. Based on the selected operating conditions, the effects of variables such as pressure, CO₂ capture capacity, solid inventory, CO conver sion and CO₂ capture efficiency have been investigated as well.

매체순환식 가스연소기용 산소공여입자들의 연료별 연소특성

류호정,김경수,박영성,박문희 한국수소및신에너지학회 2009 한국수소 및 신에너지학회논문집 Vol.20 No.1

Reduction reactivity and carbon deposition characteristics of three oxygen carrier particles(OCN01, OCN02, OCN03) have been investigated by using hydrogen, methane, syngas, and natural gas as fuels. For all particles, the maximum conversion, the oxygen transfer capacity, and the degree of carbon deposition increased as the reactive carbon contents increased. The reduction rate and the oxygen transfer rate increased as the moles of required oxygen per input gas increased. The change of maximum conversion, reduction rate, oxygen transfer capacity, oxygen transfer rate and degree of carbon deposition for different fuels can be explained consistently by using parameters such as the reactive carbon contents and the moles of require oxygen per input gas.

CO2/H2 원천분리 SMART 시스템의 수소생산특성

류호정 한국수소및신에너지학회 2007 한국수소 및 신에너지학회논문집 Vol.18 No.4

To check the feasibility of SMART(Steam Methane Advanced Reforming Technology) system, an experimental investigation was performed. A fluidized bed reactor of diameter 0.052m was operated cyclically up to 10th cycle, alternating between reforming and regeneration conditions. FCR-4 catalyst was used as the reforming catalyst and calcined limestone(domestic, from Danyang) was used as the CO2 absorbent. Hydrogen concentration of 98.2% on a dry basis was reached at 650℃ for the first cycle. This value is much higher than H2 concentration of 73.6% in the reformer of conventional SMR (steam methane reforming) condition. The hydrogen concentration decreased because the CO2 capture capacity decreased as the number of cycles increased. However, the average hydrogen concentration at 10th cycle was 82.5% and this value is also higher than that of SMR. Based on these results, we could conclude that the SMART system can replace SMR system to generate pure hydrogen without HTS (high tempeature shift), LTS (low temperature shift) and CO2 separation process.

매체순환식 가스연소기술 개발동향

류호정 한국연소학회 2008 KOSCOSYMPOSIUM논문집 Vol.- No.-

회분식 유동층 반응기에서 매체순환식 가스연소기용 대량생산 산소공여입자들의 천연가스 연소특성

류호정,김경수,박영성,박문희 한국수소및신에너지학회 2009 한국수소 및 신에너지학회논문집 Vol.20 No.2

Natural gas combustion characteristics of mass produced oxygen carrier particles were investigated in a batch type bubbling fluidized bed reactor. Five particles, NiO/bentonite, OCN601-650, OCN702-1100, OCN703-950, OCN703-1100 were used as oxygen carrier particles. Natural gas and air were used as reactants for reduction and oxidation, respectively. During reduction reaction, high fuel conversion and high CO₂ selectivity were achieved for most of oxygen carriers. During oxidation, NO emission was very low. These results indicate that inherent CO₂ separation and low NOx combustion are feasible for the natural gas fueled chemical-looping combustion system. Among the five oxygen carriers, OCN703-1100 particle was selected as the best candidate for demonstration of long-term operation in large-scale chemical-looping combustor from the viewpoints of fuel conversion, CO₂ selectivity, CH₄ concentration, and CO concentration.

산소공여입자에 의한 석탄의 직접연소 특성

류호정,이충원,이동호,배달희,이승용,박영성 한국수소및신에너지학회 2014 한국수소 및 신에너지학회논문집 Vol.25 No.1

Direct combustion characteristics of coal and oxygen carrier were measured in the thermogravimetricanalyzer using four coals and two different oxygen carriers. The direct combustion efficiency decreased in orderof Roto, Kideco, Sunhwa and Hyper coal for both oxygen carriers. Moreover, OCN703-1100 oxygen carrier showedbetter combustion efficiency than OCN706-1100 oxygen carrier for all four coals. The reduction characteristicsof two oxygen carriers for CH4, CO and H2 gases were measured in the thermogravimetric analyzer to investigatewhy OCN703-1100 oxygen carrier showed better combustion efficiency than OCN706-1100 for all coals. TheOCN703-1100 oxygen carrier represented higher reduction rate than OCN706-1100 for all reducing gases. Moreover, the total pore area and the porosity of OCN703-1100 were higher than those of OCN706-1100 oxygencarrier. The total volatile gas and volatile components of four coals were measured in a batch type fluidized bedreactor to investigate why the direct combustion efficiency decreased in order of Roto, Kideco, Sunhwa and Hypercoal for both oxygen carriers. The direct combustion efficiency was proportional to the total amount of (CH4+CO+H2) produced during devolatilization of coals.

SEWGS 공정을 위한 유동층 반응기에서 내부 삽입물의 모양 및 WGS 촉매의 형상이 CO 전환율에 미치는 영향

류호정,김하나,이동호,배달희,황택성 한국수소및신에너지학회 2013 한국수소 및 신에너지학회논문집 Vol.24 No.2

To enhance the performance of SEWGS system by holding the WGS catalyst in a SEWGS reactor using bed inserts, effects of insert geometry and shape of WGS catalysts on CO conversion were measured and investigated. Small scale fluidized bed reactor was used as experimental apparatus and WGS catalyst (particle and tablet) and sand were used as bed materials. The parallel wall type and cross type bed inserts were used to hold the WGS catalysts. The CO conversion with steam/CO ratio was determined based on the exit gas analysis. The measured CO conversion using the bed inserts showed high value comparable to physical mixing cases. Moreover, gas flow direction was confirmed by bed pressure drop measurement for each case. Most of input gas flowed through the catalyst side when we charged tablet type catalyst into the bed insert and this can cause low CO2capture efficiency because the possibility of contact between input gas and CO2 absorbent is low in this case. New bed insert geometry was proposed based on the results from this study to enhance contact between input gas and WGS catalyst and CO2 absorbent.

SEWGS 시스템을 위한 WGS 촉매들의 CO 전환 특성

류호정,박지혜,이동호,박재현,배달희 한국수소및신에너지학회 2015 한국수소 및 신에너지학회논문집 Vol.26 No.2

Reactivity of commercial WGS catalyst(MDC-7) and four new catalysts(RMC-3, PC-73, PC-67SU, PC-59) manufactured with various compositions by Korea Electric Power Research Institute(KEPCO RI) were compared to select suitable WGS catalyst for SEWGS system. Steam/CO ratio, gas velocity, flow rates of syngas, and temperature were considered as operating variables. As a result, MDC-7 catalyst showed the highest CO conversion and RMC-3 catalyst showed also high CO conversion. Therefore, MDC-7 and RMC-3 catalysts were selected as applicable catalysts. However, PC-73 catalyst showed low CO conversion at low temperature(200℃) but showed good reactivity at high temperature(225~250℃), and therefore, PC-73 catalyst was selected as applicable catalyst for high temperature operation. Continuous operations up to 24 hours for those three catalysts(MDC-7, RMC-3, PC-73) were conducted to check reactivity decay of catalysts. All three catalysts maintained their original reactivity.