• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.779-783
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• 2007

본 연구에서는 가스화공정과 수성가스 전환공정, $CO_2$ 분리공정, 메탄화 공정을 주요 구성으로 한 대체(또는 합성)천연가스(SNG, Substitute or Synthetic Natural Gas)제조공정을 대상으로 석탄, 석탄 촤, 바이오매스 등의 다양한 고체시료를 적용하였을 경우 각 시료의 가스화 반응을 통해 얻어진 합성가스를 이용한 SNG 제조 공정 특성을 파악하고자 하였다. 석탄, 석탄 촤, 바이오매스를 적용한 SNG 공정해석 결과 가스화 공정, 수성가스 전환 공정, 메탄화 공정의 운전 용도가 각 800도, 450도, 300도이고, 수성가스 전환 공정 출구의 합성가스 $H_2$/CO ratio(mol basis)가 3인 조건에서 SNG/Feed ratio는 석탄, 석탄 촤, 바이오매스가 각각 0.35, 0.34, 0.08로 나타났고. SNG Efficiency(%) 는석탄, 석탄 촤 바이오매스에 대해서 각각 61.2%. 48.2%, 17.5%로 나타났다. 또한, 석탄 촤를 대상으로 가스화 공정에서의 산화제 투입 조건 및 스팀 투입조건의 변화에 따른 합성가스 발생 특성을 살펴보았다.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.10
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• pp.704-710
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• 2014

Biomass is considered an alternative energy which can solve an greenhouse gas problem like $CO_2$ which is a major contributor to global warming. The biomass can be converted to various energy sources through thermochemical conversion. In this study, a continuous gasifier was engineered for a wood biomass gasification. The biomass was used a waste wood. The experiments of $CO_2$ gasification were achieved as the gasification temperature, moisture content and input $CO_2$ concentration. The results showed that the yield of producer gas increased with an increasing the gasification temperature. The amount of the light tar increased due to the decomposition of gravimetric tar by the thermal cracking, and the char was confirmed pore development through the SEM analysis. The CO concentration was increased with an increased input $CO_2$ concentration from Boudouard reaction. Through the parametric screening studies, the hydrogen and carbon monoxide concentration were 32.91% and 48.33% at the optimal conditions of this test rig.

• 한국연소학회:학술대회논문집
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• 2013.06a
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• pp.69-72
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• 2013

This study investigates the characteristics of biochar by slow pyrolysis at $500^{\circ}C$ for various biomass residues. Six biomass materials were tested: Tree bark, Tree stem, bagasse, cocopeat, paddy straw and palm kernel shell. In the biochar yield, the effect of ash in the raw biomass was significant for paddy straw. Excluding the ash content, the timber bark, bagasse and paddy straw had a similar biochar yield of 26-29 wt.%. Tree stem and bagasse had well developed pores in a wide size range and large surface area over $200m^2/g$. Cocopeat and PKS has significantly higher biochar yield due to the increased content of lignin, but the development of intra-particle pores and microscopic surface area was very poor. The elemental composition, pH and other properties of the biochar samples were also compared.

• Korean Chemical Engineering Research
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• v.56 no.5
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• pp.725-731
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• 2018

The effects of catalysts addition on the carbonization reaction of biomass have been studied in a thermogravimetric analyzer (TGA). The sample biomasses were Bamboo and Pine. The catalysts tested were K, Zn metal compounds. The carbonization reactions were tested in the nonisothermal condition from the room temperature to $850^{\circ}C$ at a heating rate $1{\sim}10^{\circ}C/min$ on the flowing of $N_2$ purge gases. Also, the effects of catalyst on the torrefaction were tested in the temperature condition of 220, 250, $280^{\circ}C$ at 30 min. Combustion characteristic for the torrefied catalyst biomass were studied in the nonisothermal conditions of $200{\sim}850^{\circ}C$. As the results, the initial decomposition temperatures of the volatile matters ($T_i$) and the temperature of maximum reaction rate ($T_{max}$) were decreased with increasing the catalyst amounts in the sample biomass. The char amounts remained after carbonization at $400^{\circ}C$ increased with the catalyst amounts. Therefore catalysts addition can be decreased the energy for carbonization process and improved the heating value of product char. The catalysts reduced the optimum torrefaction conditions from $250^{\circ}C$ to $220^{\circ}C$. The torrefied catalyst biomass have lower activated energy from 46.5~58.7 kJ/mol to 25.1~27.0 kJ/mol in the nonisothermal combustion reaction.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.102.1-102.1
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• 2010

바이오매스(Biomass)는 지구상에서 에너지원으로 이용될 수 있는 모든 식물과 미생물을 총칭하는 의미로 사용된다. 최근 바이오매스를 에너지자원화 시키는 방법으로 주목받는 열화학적 전환(Thermo-chemical conversion) 반응은 산소가 없이 혹은 희박한 조건에서 바이오매스에 열과 압력을 가하거나 공기나 수증기 등의 가스화제와 반응하여 바이오오일(Bio-oil) 및 합성가스(Syngas)로 변화하는 프로세스를 의미한다. 바이오매스로부터 바이오 DME(Di-Methyl Ether) 생산을 위한 합성가스를 제조하기 위해서 국내 산림자원을 대상으로 열분해반응 특성연구를 수행하였다. 또한 이들 물질로부터 바이오 DME 합성을 위해 최적의 합성가스 제조를 위한 타당성 연구를 수행하였다. 반응온도 $800{\sim}900^{\circ}C$에서 가스화 수율은 78~80%, 촤 수율은 17~20%, 타르 수율은 4~10%였고, 합성가스($H_2$/CO)비는 0.9~1.6였다.

• Transactions of the Korean hydrogen and new energy society
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• v.31 no.1
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• pp.122-131
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• 2020

To reduce emissions from coal-fired power plants, researchers focusing on coal and biomass co-firing technology. Biomass, with its carbon-neutral nature and lower quantities of nitrogen and sulfur compared with coals, has a positive impact on coal-fired power generation. Many studies on the combustion of biomass have been conducted, but the study on the combustion characteristics of biomass char is limited. FERPM predicts char combustion characteristics with high accuracy by introducing experimental data-based parameters of biomass char and has not yet been applied in numerical simulation. In this study, FERPM is numerically applied to char combustion of wood pellets representing wood-based biomass and the combustion characteristics are compared with the kinetic/diffusion limited model, intrinsic model, and diffusion limited model.

• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.76-82
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• 2012

Biomass and coal are great potential energy sources for gasification process. These solids can be gasified to produce syngas and bio-oil which can be upgraded further to transportation fuel. Two biomass and three coals have been gasified with steam in a thermobalance reactor under atmospheric pressure in order to evaluate their kinetic rate information The effects of gasification temperature ($600{\sim}850^{\circ}C$) and partial pressure of steam (30~90 kPa) on the gasification rate have been investigated. The three different types of gas-solids reaction models have been applied to the experimental data to compare their predictions of reaction behavior. The modified volumetric reaction model predicts the conversion data well, thus that model was used to evaluate kinetic parameters in this study. The gasification reactivity of five solids has been compared. The obtained activation energy of coal and biomass gasification were well in the reasonable range. The expression of apparent reaction rates for steam gasification of five solids have been proposed as basic information for the design of coal gasification processes.

• Korean Chemical Engineering Research
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• v.53 no.6
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• pp.746-754
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• 2015

In this study, we investigated the effects of the temperature on the coal/biomass $char-CO_2$ gasification reaction under isothermal conditions of $700{\sim}900^{\circ}C$ using the lignite(Indonesia Eco coal) with biomass (korea cypress). Ni catalysts were impregnated on the coal by the ion-exchange method. Four kinetic models which are shrinking core model (SCM), volumetric reaction model (VRM), random pore model (RPM) and modified volumetric reaction model (MVRM) for gas-solid reaction were applied to the experimental data against the measured kinetic data. The Activation energy of Ni-coal/biomass, non-catalyst coal/biomass $Char-CO_2$ gasification was calculated from the Arrhenius equation.

• Journal of the Korean Wood Science and Technology
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• v.40 no.6
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• pp.445-453
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• 2012

In this study the effects of particle size and water content on the yields and physical/chemical properties of pyrolytic products were investigated through fast-pyrolysis of yellow poplar. Water content was critical parameters influencing the properties of bio-oil. The yields of bio-oil were increased with decreasing water content. However, the yield of pyrolytic product was not clearly influenced by feedstock's particle size. The water content, pH and HHV (Higher Heating Value) of bio-oil were measured to 20~30%, 2.2~2.4 and 16.6~18.5MJ/kg, respectively. The water content of feedstock was clearly influenced to water content of bio-oil. In terms of bio-char, HHV of them were measured to 26.2~30.1 MJ/kg with high content of carbon over 80%.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.107-107
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• 2010

Hydrogen is an alternative fuel for the future energy which can reduce pollutants and greenhouse gases. Synthesis gas have played an important role of synthesizing the valuable chemical compound, for example methanol, DME and GTL chemicals. Renewable biomass feedstocks can be potentially used for fuels and chemical production. Current thermal processing techniques such as fast pyrolysis, slow pyrolysis, and gasification tend to generate products with a large slate of compounds. Lignocellulose feedstocks such as forest residues are promising for the production of bio-oil and synthesis gas. Pyrolysis and gasification was investigated using thermogravimetric analyzer (TGA) and bubbling fluidized bed gasification reactor to utilize forest woody biomass. Most of the materials decomposed between $320^{\circ}C$ and $380^{\circ}C$ at heating rates of $5{\sim}20^{\circ}C/min$ in thermogravimetric analysis. Bubbling fluidized bed reactor were use to study gasification characteristics, and the effects of reaction temperature, residence time and feedstocks on gas yields and selectivities were investigated. With increasing temperature from $750^{\circ}C$ to $850^{\circ}C$, the yield of char decreased, whereas the yield of gas increased. The gaseous products consisted of mostly CO, CO2, H2 and a small fraction of C1-C4 hydrocarbons.