• Transactions of the Korean hydrogen and new energy society
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• v.25 no.3
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• pp.247-254
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• 2014

The synthesis of Fischer-Tropsch oil is the catalytic hydrogenation of CO to give a range of products, which can be used for the production of high-quality diesel fuel, gasoline and linear chemicals. Our cobalt based catalyst was prepared Co/alumina, silica and titania by the incipient wet impregnation of the nitrates of cobalt and promoter with supports. Cobalt catalysts was calcined at $350^{\circ}C$ before being loaded into the FT reactors. After the reduction of catalyst has been carried out under $450^{\circ}C$ for 24hrs, FT reaction of the catalyst has been carried out at GHSV of 4,000/hr under $200^{\circ}C$ and 20atm. From these test results, we have obtained the results as following ; in case of 12wt% Co-supported $Al_2O_3$, $SiO_2$ and $TiO_2$ catalysts, maximum activities of the catalysts were appeared at the promoters of Mn, Mo and Ce respectively. The activity of 12wt% $Co/Al_2O_3$ added a Mn promoter was about 3 times as high as that of 12wt% $Co/Al_2O_3$ catalyst without promoters. When it has been the experiment at the range of reaction temperature of $200{\sim}220^{\circ}C$ and GHSV of 1,546~5,000/hr, the results have shown generally increasing the activities with the increase of reaction temperature and GHSV.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.829-831
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• 2009

폐기물, 석탄 등 다양한 시료의 가스화 반응을 통해서 발생되는 합성가스는 CO, $H_2$, $CO_2$가 주성분으로 가스엔진, 가스터빈 등의 연료로 사용하여 발전하거나 합성반응을 통해 다양한 화학원료로의 전환이 가능하다. 또한 폐기물, 석탄 등의 다양한 원료의 가스화 반응에 의해 발생한 합성가스로부터 F-T(Fischer-Tropsch) 합성을 통한 인조합성석유, Non F-T 합성을 통한 메탄올, DME(Dimethyl Ether) 등을 제조할 수 있으며, 메탄화 반응을 통해 대체천연가스(SNG, Substitute Natural Gas)로 제조하여 활용하는 방안도 가능하다. 또한 현재 상업용 규모의 수소 제조 방법 중에서 가장 경제적인 방법으로 천연가스를 개질하여 CO, $H_2$가 주성분인 합성가스를 만든 다음 수성가스 전환, PSA(Pressure Swing Adsorption)통해 $CO_2$와 $H_2$를 분리하여 생산하고 있으나, 천연가스 가격의 상승 및 다양한 시료로부터 향후 경제성 확보가 가능한 수소 제조 방법에 대한 연구가 진행되고 있으며, 석탄 가스화 및 폐기물 가스화를 통해 얻어진 합성가스로부터의 수소 제조 공정이 개발 및 상업화 추진되고 있다. 본 연구에서는 폐기물 가스화를 통해 발생한 합성가스에 대하여 수성가스 전환 반응을 통한 수소 생산 특성 및 수성가스 전환 반응의 공간속도 변화 및 스팀주입량 변화에 따른 반응 특성을 고찰하였다.

• Transactions of the Korean hydrogen and new energy society
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• v.26 no.4
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• pp.339-346
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• 2015

The synthesis of Fischer-Tropsch (FT) oil is the catalytic hydrogenation of CO to give a range of products, which can be used for the production of high-quality diesel fuel, gasoline and linear chemicals. This studied catalyst was prepared Cobalt-supported alumina and silica by the incipient wet impregnation of the nitrates of cobalt, promoter and organic solvent with supports. Cobalt catalysts were calcined at $350^{\circ}C$ before being loaded into the FT reactors. After the reduction of catalyst has been carried out under $450^{\circ}C$ for 24h, FT reaction of the catalyst has been carried out at GHSV of 4,000/hr under $200^{\circ}C$ and 20atm. From these experimental results, we have obtained the results as following; In case of $SiO_2$ catalysts, the activity of 12wt% $Cobalt-SiO_2$ synthesized by organic solvent was about 2 or 3 times higher than the activity of 12wt% $Cobalt-SiO_2$ catalyst synthesized without organic solvent. In particular, the activity of the $Cobalt-SiO_2$ catalyst prepared in the presence of an organic solvent P was two to three times higher than that of the $Cobalt-SiO_2$ catalyst prepared without the organic solvent. Effect of Cr and Cu metal as a promoter was found little. 200 h long-term activity test was performed with a $Co/SiO_2$ catalyst prepared in the presence of an organic solvent of Glyoxal solution.

• Korean Chemical Engineering Research
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• v.58 no.1
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• pp.69-83
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• 2020

Light olefins are important petrochemicals as well as primary building blocks for various chemical intermediates. As the number of ethane cracking center (ECC) process, in which ethylene accounts for most of the production, has increased in recent years, propylene supply is not catching up with steadily increasing propylene demand. This trend makes the conversion of methanol to olefins to get more industrial importance. The methanol to olefins (MTO) process produces methanol through syngas and obtain olefins such as propylene through methanol. Since the reaction from methanol to olefins provides different product compositions depending on the catalyst used for the reaction, it is important to choose an appropriate separation process for the reaction product with different composition. Four different separation processes are considered for four representative cases of product compositions. The separation processes for the reaction products are evaluated by techno-economic analysis based on the simulation results using Aspen plus. Guidelines are provided for selecting a suitable separation process for each of representative case of product compositions in the MTO process.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.2
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• pp.165-174
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• 2010

The numerical modeling of a coal gasification reaction occurring in an entrained flow coal gasifier is presented in this study. The purposes of this study are to develop a reliable evaluation method of coal gasifier not only for the basic design but also further system operation optimization using a CFD(Computational Fluid Dynamics) method. The coal gasification reaction consists of a series of reaction processes such as water evaporation, coal devolatilization, heterogeneous char reactions, and coal-off gaseous reaction in two-phase, turbulent and radiation participating media. Both numerical and experimental studies are made for the 1.0 ton/day entrained flow coal gasifier installed in the Korea Institute of Energy Research (KIER). The comprehensive computer program in this study is made basically using commercial CFD program by implementing several subroutines necessary for gasification process, which include Eddy-Breakup model together with the harmonic mean approach for turbulent reaction. Further Lagrangian approach in particle trajectory is adopted with the consideration of turbulent effect caused by the non-linearity of drag force, etc. The program developed is successfully evaluated against experimental data such as profiles of temperature and gaseous species concentration together with the cold gas efficiency. Further intensive investigation has been made in terms of the size distribution of pulverized coal particle, the slurry concentration, and the design parameters of gasifier. These parameters considered in this study are compared and evaluated each other through the calculated syngas production rate and cold gas efficiency, appearing to directly affect gasification performance. Considering the complexity of entrained coal gasification, even if the results of this study looks physically reasonable and consistent in parametric study, more efforts of elaborating modeling together with the systematic evaluation against experimental data are necessary for the development of an reliable design tool using CFD method.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.11
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• pp.636-641
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• 2015

Waste energy conversion to SRF (Solid Refuse Fuel) has the effects not alternative fossil fuel usage but also the reduction of greenhouse gas. But the direct burning of the SRF including a plastic waste generates air pollution problem like soot, dioxin, etc. so that an application of pyrolysis and gasification treatment should be needed. The purpose of this study is to supply a basic thermal data of the pyrolysis gasification characteristics in the plastic-rich SRF which are needed for developing the novel pyrolyser or gasifier. To do so, a bench-scale test rig was newly engineered, and then experiments were achieved for the production characteristics of gas, tar, and char. While SRF sample, gasification air ratio, holding time changed as 2 g, 0.691, 32 min respectively, the $H_2$ 1.36%, $CH_4$ 2.18%, CO 1.88%, $Cl_2$ 15.9 ppm, HCl 6.4 ppm were composed. Also light tar benzene $4.03g/m^3$, naphthalene $0.39g/m^3$, anthracene $0.11g/m^3$, pyrene $0.06g/m^3$, gravimetric tar $18g/m^3$, and char 0.29 g was formed.

• Korean Chemical Engineering Research
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• v.50 no.6
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• pp.1015-1020
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• 2012

Lignite of low rank coal and petroleum coke of high sulfur content can be high potential energy sources for coal gasification process because of their plentiful supply. The steam gasification of lignite, anthracite, and pet coke has been carried out in both an atmospheric thermobalance reactor and a lab-scale fludized bed reactor (0.02 m i.d. ${\times}$ 0.6 m height). The effects of gasification temperature ($600{\sim}900^{\circ}C$) and partial pressure of steam (0.15~0.95 atm) on the gasification rate and on the heating value of product gas have been investigated. The modified volumetric reaction model was applied to the experimental data to describe the behavior of carbon conversion, and to evaluate kinetic parameters of char gasification. The results shows that higher temperature bring more hydrogen in the product syngas, and thus increased gas heating value. The feed rate of steam is needed to be optimized because an excess steam input would lower the gasification temperature which results in a degradation of fuel quality. The rank of calorific value of the product gas was anthracite > lignite > pet coke. Their obtained calorific value at $900^{\circ}C$ with 95% steam feed were 10.0 > 6.9 > 5.7 $MJ/m^3$. This study indicates that lignite and pet coke has a potential in fuel gas production.

• Clean Technology
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• v.24 no.2
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• pp.99-104
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• 2018

In this work, we performed the methanation reaction using synthesis gas ($H_2/CO_2$) for the process to produce synthetic natural gas (SNG) for $4^{th}$ methanation reactor in SNG process proposed by RIST-IAE. Experimental conditions were changed with temperature, pressure and space velocity. At this time, $CO_2$ conversion, $CH_4$ selectivity and $H_2$ concentration after reaction were investigated. As a result, $CH_4$ selectivity by the $CO_2$ methanation increased with lower space velocity and higher pressure. On the other hand, in the case of temperature, the maximum value was shown at $320^{\circ}C$. From these results, it was found that the optimum condition of the fourth reactor suitable for the SNG process was obtained.

• Resources Recycling
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• v.27 no.2
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• pp.38-47
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• 2018

Integrated gasification combined cycle (IGCC) is a next generation energy production technology that converts coal into syngas with enhanced power generation efficiency and environmental performance. IGCC produces almost coal gasification slag as the solid by-product. IGCC slag is generated about 140,000 tons for a year although recycling of it is still in the early stages. We evaluated the potential of IGCC slag which is generated from a pilot plant in South Korea as an alkali-activated cement. Samples which were activated with the combined activator of sodium silicate solution and caustic soda had an average compressive strength of 4.5 MPa, showing expansion. Expansion of the alkali-activated slag was presumed to be caused by free CaO in the slag, although it was not detected by the ethylene glycol method. Samples that were activated with the combined activator of sodium aluminate and caustic soda had an average compressive strength of 10 MPa. Hydroxy sodalite and $C_3AH_6$ were found to be the new crystalline phases. IGCC slag can be used as an alkali-activated material, but the strength performance should be improved with proper mix design approach to calculate optimum proportions which can alleviate the expansion issue at the same time.

• Journal of the Korean Applied Science and Technology
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• v.29 no.3
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• pp.450-458
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• 2012

In order to reduce the effects of greenhouse gas (GHG) emissions, the South Korean government has announced a special platform of technologies as part of an effort to minimize global climate change. To further this effort, the Korean government has pledged to increase low-carbon and carbon neutral resources for biofuel derived from biomass to replace fossil and to decrease levels of carbon dioxide. In general, second generation biofuel produced form woody biomass is expected to be an effective avenue for reducing fossil fuel consumption and greenhouse gas (GHG) emissions in road transport. It is important that under the new Korean initiative, pilot scale studies evolve practices to produce biomass-to-liquid (BTL) fuel. This study reports the quality characteristics of F-T(Fischer-Tropsch) diesel for production of BTL fuel. Synthetic F-Tdiesel fuel can be used in automotive diesel engines, pure or blended with automotive diesel, due to its similar physical properties to diesel. F-T diesel fuel was synthesized by Fischer-Tropsch (F-T) process with syngas($H_2$/CO), Fe basedcatalyst in low temperature condition($240^{\circ}C$). Synthetic F-T diesel with diesel compositions after distillation process is consisted of $C_{12}{\sim}C_{23+}$ mixture as a kerosine, diesel compositions of n-paraffin and iso-paraffin compounds. Synthetic F-T diesel investigated a very high cetane number, low aromatic composition and sulfur free level compared to automotive diesel. Synthetic F-T diesel also show The wear scar of synthetic F-T diesel show poor lubricity due to low content of sulfur and aromatic compounds compared to automotive diesel.