• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3241-3246
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• 2007

Integrated Gasification Combined Cycle (IGCC) power plant converts coal to syngas, which is mainly composed with hydrogen and carbon monoxide, by the gasification process and produces electric power by the gas and steam turbine combined cycle power plant. The purpose of this study is to investigate the influence of the syngas to the performance of a gas turbine in a combined cycle power plant. For this purpose, a commercial gas turbine is selected and its performance characteristics are analyzed with three different fuels, i.e., natural gas ($CH_4$), syngas and hydrogen. It is found that different heating values of those fuels and chemical compositions in their combustion gases are the causes in the different performance characteristics.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.1237-1242
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• 2008

A study on waste heat utilization of melted slags at pyorlysis, gasification and melting system was performed. Researchers studied heat balance of substances that flow and flow out to the system which is consisted of melting furnace, combustion chamber, and waste heat boiler, then they calculated melting slags' quantity of heat by the first law of thermodynamics. If they use water cursh pit outflow which is gotten by quenching of melting slag as a energy for heating and cooling system, steam of waste heat boiler would be delivered to a steam turbine, making energy, then they will get 67,671,000 won of profit a year. It will take 3 years to repossess the cost that they invested for building it. And, if we predict durability of trash burner is 20 years, we will get approximately 1,150,407,000 won of profits in 17 years without the period when we repossess the building costs.

• Journal of Energy Engineering
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• v.19 no.4
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• pp.215-220
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• 2010

Hydrogen is a clean and efficient energy source and is expected to take an important role in future energy demand. A possibly good route to produce hydrogen is by using biomass and organic wastes as a source through thermo-chemical conversion technology. In this study, pyrolysis of wood Pellet(Oregon pine) has been carried out in batch type fixed-bed reactor in $N_2$ atmosphere during 20 minutes to determine the optimum hydrogen generating conditions. At the influence of temperature, hydrogen yield was increased with increasing temperature. For the influence of Steam/Biomass Ratio(SBR), hydrogen yield was increased by steam addition at low temperature condition. However, effect of steam addition was insignificant over at SBR = 1. The hydrogen yield was increased with increasing SBR at high temperature condition. From result of $H_2$/CO and $H_2/CH_4$ ratio, dominant reaction was steam reforming in this experimental condition. The optimum condition for hydrogen production was determined as follows: $H_2$ yield = 38.3 vol.% (56.01 L/min kg) at $900^{\circ}C$, SBR=3.

• Journal of Energy Engineering
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• v.25 no.4
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• pp.214-225
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• 2016

Gasification is one of the important contribution to resource recycling by conversion of biomass to a variety of energy sources such as alcohol, SNG etc., and to global warming prevention by reduction of green house gases such as $CO_2$. The aim of this study is to draw the optimal operation condition of dual fluidized-bed gasifier with biomass fuel, to verify SNG production efficiency and to establish the basis for the domestic commercialization of dual fluidized bed gasification. As a result, dual fluidized-bed gasifier has the optimal conditions at $826^{\circ}C$ with steam input 1,334 g/hr, air input 5.56 L/min. The carbon conversion is 81% and SNG production efficiency was $CH_4$ 92%.

• Transactions of the Korean hydrogen and new energy society
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• v.24 no.1
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• pp.12-19
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• 2013

A gasification process with pre-combustion $CO_2$ capture process, which converts coal into environment-friendly synthetic gas, might be promising option for sustainable energy conversion. In the coal gasification for power generation, coal is converted into $H_2$, CO and $CO_2$. To reduce the cost of $CO_2$ capture and to maximize hydrogen production, the removal of CO and the additional production of hydrogen might be needed. In this study, a 2l/min water gas shift system for a coal gasifier has been studied. To control the concentration of major components such as $H_2$, CO, and $CO_2$, MFCs were used in experimental apparatus. The gas concentration in these experiments was equal with syngas concentration from dry coal gasifiers ($H_2$: 25-35, CO: 60-65, $CO_2$: 5-15 vol%). The operation conditions of the WGS system were $200-400^{\circ}C$, 1-10bar. Steam/Carbon ratios were between 2.0 and 5.0. The commercial catalysts were used in the high temperature shift reactor and the low temperature shift reactor. As steam/carbon ratio increased, the conversion (1-$CO_{out}/CO_{in}$) increased from 93% to 97% at the condition of CO: 65, $H_2$: 30, $CO_2$: 5%. However the conversion decreased with increasing of gas flow and temperature. The gas concentration from LTS was $H_2$: 54.7-60.0, $CO_2$: 38.8-44.9, CO: 0.3-1%.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.533-536
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• 2009

The gasification technology is a very flexible and versatile technology to produce a wide variety products such as electricity, steam, hydrogen, Fisher-Tropsch(FT) diesels, Dimethyl Ether(DME), methanol and SNG(Synthetic Natural Gas) with near-zero pollutant emissions. Gasification converts coal and other low-grade feedstocks such as biomass, wastes, residual oil, petroleum coke, etc. to a very clean and usable syngas. Syngas is produced from gasifier including CO, $H_2$, $CO_2$, $N_2$, particulates and smaller quantities of $CH_4$, $NH_3$, $H_2S$, COS and etc. After removing pollutants, syngas can be variously used in energy and environment fields. The pilot-scale coal gasification system has been operated since 1994 at Ajou University in Suwon, Korea. The pilot-scale gasification facility consists of the coal gasifier, the hot gas filtering system, and the acid gas removal (AGR) system. The acid gas such as $H_2S$ and COS is removed in the AGR system before generating electricity by gas engine and producing chemicals like Di-methyl Ether(DME) in the catalytic reactor. The designed operation temperature and pressure of the $H_2S$ removal system are below $50^{\circ}C$ and 8 kg/$cm^2$. The iron chelate solution is used as an absorbent. $H_2S$ is removed below 0.1 ppm in the H2S removal system.

• Transactions of the Korean hydrogen and new energy society
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• v.33 no.6
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• pp.699-706
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• 2022

Recently, hydrogen production is attracting attention. In this study, a process simulation was conducted on the gasification reaction to produce hydrogen using rice husks, which are produced as by-products of rice. For this purpose, Chuchung, Odae, and Dongjin rice, which are rice varieties produced in Korea, were compared with the literature. The Korean rice contained more hydrogen and less oxygen compared to the literature. As a result of the simulation, large amounts of H₂ and CH₄ and small amounts of CO₂ and CO were produced accordingly. The conditions to maximize hydrogen production were a gasification reaction temperature of 700℃ and an Steam-to-Biomass (S/B) ratio of 0.4-0.6. However, because the S/B ratio is related to the gasification catalyst degradation, the model needs to be improved through additional experiments in the future. This study showed the possibility of hydrogen production using Korean rice husks, which had not been reported.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.345-348
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• 2008

본 연구에서는 가스화 반응, 수성가스 전환 반응, 메탄화 반응 등으로 구성된 SNG제조 공정에 대한 해석을 통해, 석탄 촤의 가스화 반응에 의해 생성된 합성가스를 이용한SNG제조 공정 특성을 파악하고자 하였고, SNG제조 공정 중 가스화 공정에 대한 실험을 통해 가스화 공정의 조건에 따른 합성가스 발생 특성 및 메탄화 반응의 특성을 살펴보았다. 석탄 촤를 대상으로 하여 가스화 공정의 $O_2$/feed ratio와 steam/feed ratio 조건 변화에 따른 합성가스 발생 특성을 살펴본 결과 steam을 투입하지 않은 경우 발생되는 합성가스 중 CO의 농도는 55$\sim$65%, $H_2$ 9$\sim$11%, $CO_2$ 24$\sim$29% 범위였고, $O_2$/feed ratio가 증가할수록 CO의 농도는 증가하고, $H_2$와 $CO_2$의 농도는 감소하는 경향을 나타내었다. 또한,steam을 투입하는 경우 합성가스 중 CO의 농도는 20$\sim$37%, $H_2$ 16$\sim$18%, $CO_2$ 42$\sim$55% 범위였다. 메탄화 공정 해석 결과 메탄의 농도를 최대로 얻을 수 있는 조건은 $H_2$/CO 비가 3인 조건이었고 온도가 낮을 수록 생성농도가 높아짐을 알 수 있었다. 가스화 특성 실험 결과 및 공정해석 결과, 메탄화 반응에 대한 실험 및 공정해석 결과는 고체시료의 가스화 반응을 통해 발생한 합성가스를 이용한 SNG 제조 공정 특성 파악 및 SNG를 제조하기 위해 필요한 단위 공정에 대한 설계 자료 및 운전조건을 결정할 수 있는 주요 인자로 활용될 수 있을 것으로 판단된다.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.113.1-113.1
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• 2010

IGCC(Integrated Coal Gasification and Combined Cycle) plants can be among the most advanced and environmental systems for electric energy generation from various feed stocks and is becoming more and more popular in new power generation fields. In this work, the performance of IGCC plants employing Shell gasification technology and a GE 7FB gas turbine engine was simulated using IPSEpro open-equation modeling environment for different operating conditions. Performance analyses and comparisons of all operating cases were performed based on the design cases. Discussions were focused on gas composition, syngas production rate and overall performance. The validation of key steady-state performance values calculated from the process models were compared with values from the provided heat and material balances for Shell coal gasification technology. The key values included in the validation included the inlet coal flow rate; the mass flow rate, heating value, and composition of major gas species (CO, H2, CH4, H2O, CO2, H2S, N2, Ar) for the syngas exiting the gasifier island; and the HP and MP steam flows exiting the gasifier island.

• Journal of the Korean Society of Combustion
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• v.4 no.1
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• pp.1-15
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• 1999

In order to analyze the sensitivity on the pulverized coal flames of the several variables, a numerical study was conducted at the gasification process. Eulerian approach is used for the gas phase, whereas lagrangian approach is used for the solid phase. Turbulence is modeled using the standard $k-{\varepsilon}$ model. The turbulent combustion incorporates eddy dissipation model. The radiation was solved using a Monte-Carlo method. One-step two-reaction model was employed for the devolatilization of Kideco coal. In pulverized flame of long liftoff height, the initial turbulent intensity seriously affects the position of flame front. The radiation heat transfer and wall heat loss ratio distort the temperature distributions along the reactor wall, but do not influence the reactor performance such as coal conversion, residence time and flame front position. The primary/secondary momentum ratio affects the position of flame front, but the coal burnout is only slightly influenced. The momentum ratio is a variable only associated with the flame stabilization such as flame front position. The addition of steam in the reactor has a detrimental effect on all the aspects, particularly reactor temperature and coal burnout.