• Journal of Korean Society of Environmental Engineers
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• v.35 no.10
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• pp.710-716
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• 2013

New and renewable energy sources have drawn attention because of climate change. Many studies have been carried out in waste-to-energy field. Fast pyrolysis of waste lignocelluosic biomass is one of the waste-to-energy technologies. Bubbling fluidized bed (BFB) reactor is widely used for fast pyrolysis of the biomass. In BFB pyrolyzer, bubble behavior influences on the chemical reaction. Accordingly, in the present study, hydrodynamic characteristics and fast pyrolysis reaction of waste lignocellulosic biomass occurring in a BFB pyrolyzer are scrutinized. The computational fluid dynamics (CFD) simulation of the fast pyrolysis reactor is carried out by using Eulerian-Granular approach. And two-stage semi-global kinetics is applied for modeling the fast pyrolysis reaction of waste lignocellulosic biomass. To summarize, generation and ascendant motion of bubbles in the bed affect particle behavior. Thus biomass particles are well mixed with hot sand and consequent rapid heat transfer occurs from sand to biomass particles. As a result, primary reaction is observed throughout the bed. And reaction rate of tar formation is the highest. Consequently, tar accounts for 66wt.% of the product gas. However, secondary reaction occurs mostly in the freeboard. Therefore, it is considered that bubble behavior and particle motions hardly influences on the secondary reaction.

• Environmental Analysis Health and Toxicology
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• v.23 no.3
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• pp.187-194
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• 2008

국내에서 목질계 바이오매스는 유망한 재생가능한 자원이다. Fast pyrolysis을 통한 radiata pine 톱밥의 bio-oil의 전환은 벤치스케일의 유동층 반응기을 이용하였다. 이 실험에서 얻어진 bio-oil은 주로 산, 페놀, 알킬페놀 등을 포함하고 있었고. 세포생존율실험, comet assay, 물벼룩 급성유영저해실험을 이용하여 각각 세포독성, 유전독성 및 생태독성을 평가하였다. Bio-oil의 액상부분은 타르 부분보다 세포독성과 유전독성이 더 높게 나타났고, 반면 타르부분은 액상부분에 비해 생태독성이 높게 나타났다. 본 연구에서 얻어진 결과를 통해 pyrolysis 생성물에 대한 다양한 독성영향을 확인할 수 있었으나, 보다 다양한 독성 지표의 적용이 필요할 것으로 보인다.

• Journal of the Korean Applied Science and Technology
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• v.31 no.3
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• pp.453-465
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• 2014

The paper provides a review on bio-oil production technology from biomass by using fast pyrolysis to use heating fuel, power fuel and transport fuel. One of the most promising methods for a small scale conversion of biomass into liquid fuels is fast pyrolysis. In fast pyrolysis, bio-oil is produced by rapidly heating biomass to intermediate temperature ($450{\sim}600^{\circ}C$) in the absence of any external oxygen followed by rapid quenching of the resulting vapor. Bio-oil can be produced in weight yield maximum 75 wt% of the original dry biomass and bio-oils typically contain 60-75% of the initial energy of the biomass. In this study, it is described focusing on the characterization of feedstock, production principle of bio-oil, bio-oil's property and it's application sector.

• Journal of the Korean Wood Science and Technology
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• v.39 no.1
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• pp.86-94
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• 2011

Pyrolytic lignin was obtained from biooil produced with yellow poplar wood. Fast pyrolysis was performed under various temperature ranges and residence times using fluidized bed type reactor. Several analytical methods were adopted to characterize the structure of pyrolytic lignin as well as the effect of pyrolysis temperature and residence time on the modification of the lignin. The yield of pyrolytic lignin increased as increasing pyrolysis temperature and decreasing residence time of pyrolysis products. The molecular weight of pyrolytic lignin determined by gel permeation chromatography (GPC) was approximately 1,200 mol/g, which was approximately a tenth of milled wood lignin (MWL) purified from the same woody biomass. Based on analytical data, demethoxylation and side chain cleavage reaction were dominantly occurred during fast pyrolysis.

• Journal of the Korean Society of Tobacco Science
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• v.17 no.2
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• pp.160-169
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• 1995

A mathematical model for the pyrolysis processes during unforced smoldering of cigarette was proposed in this study by analyzing the physical model of the smoldering cigarette (including the establishment of burning front between burning zone and pyrolysis zone, and analyzing the involvement of main factors such as pyrolysis of virgin tobacco, evaporation of water, and internal heat transport in the processes). Thermal conduction of cigarette paper and convective and radiative heat transfer at the outer surface were also considered via the thermal resistance law for the competitive heat transfer mechanisms. The governing partial differential equations were solved using an integral method. Model predictions of smoldering speed, or linear burn rate, as well as temperature and density profiles in the pyrolysis zone for different kinds of cigarettes were found to be close to the experimental data in the literature (Muramatsu, 1981). The model provides a relatively fast and efficient way to simulate the pyrolysis processes and offers a practical tool for exploring important parameters for a smoldering cigarette, such as blended tobacco composition, properties of cigarette paper, and heat flux from the burning zone to the pyrolysis zone.

• Clean Technology
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• v.29 no.3
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• pp.200-216
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• 2023

Ginkgo leaves are considered waste biomass and can cause problems due to the strong insecticidal actions of ginkgolide A, B, C, and J and bilobalide. However, Ginkgo leaf biomass has high organic matter content that can be converted into fuels and chemicals if suitable technologies can be developed. In this study, the effect of pyrolysis temperature, minimum fluidized velocity, and Ginkgo leaf size on product yields and product properties were systematically analyzed. Fast pyrolysis was conducted in a bubbling fluidized bed reactor at 400 to 550℃ using silica sand as a bed material. The yield of pyrolysis liquids ranged from 33.66 to 40.01 wt%. The CO₂ and CO contents were relatively high compared to light hydrocarbon gases because of decarboxylation and decarbonylation during pyrolysis. The CO content increased with the pyrolysis temperature while the CO₂ content decreased. When the experiment was conducted at 450℃ with a 3.0×U_mf fluidized velocity and a 0.43 to 0.71 mm particle size, the yield was 40.01 wt% and there was a heating value of 30.17 MJ/kg, respectively. The production of various phenol compounds and benzene derivatives in the bio-oil, which contains the high value products, was identified using GC-MS. This study demonstrated that fast pyrolysis is very robust and can be used for converting Ginkgo leaves into fuels and thus has the potential of becoming a method for waste recycling.

• Journal of ILASS-Korea
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• v.17 no.4
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• pp.197-204
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• 2012

The vast stores of biomass available in the worldwide have the potential to displace significant amounts of fuels that are currently derived from petroleum sources. Fast pyrolysis of biomass is one of possible paths by which we can convert biomass to higher value products. The wood pyrolysis oil (WPO), also known as the bio crude oil (BCO), has been regarded as an alternative fuel for petroleum fuels to be used in diesel engine. However, the use of WPO in a diesel engine requires modifications due to low energy density, high water contents, low acidity, and high viscosity of the WPO. One of the easiest way to adopt WPO to diesel engine without modifications is emulsification of WPO with diesel or bio diesel. In this study, a DI diesel engine operated with diesel, bio diesel (BD), WPO/BD emulsion was experimentally investigated. Performance and gaseous & particle emission characteristics of a diesel engine fuelled by WPO/BD emulsion were examined. Results showed that stable engine operation was possible with emulsion and engine output power was comparable to diesel and bio diesel operation.

• Journal of ILASS-Korea
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• v.16 no.3
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• pp.152-158
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• 2011

Fast pyrolysis of biomass is one of the most promising technologies for converting biomass to liquid fuels. The pyrolysis oil, also known as the bio crude oil (BCO), have been regarded as an alternative fuel for petroleum fuels to be used in diesel engine. However, the use of BCO in diesel engine requires modifications due to low energy density, high water contents, low acidity, and high viscosity of the BCO. One of the easiest way to adopt BCO to diesel engine without modifications is the use of BCO/diesel emulsions. In this study, a diesel engine operated with diesel, bio diesel (BD), and BCO/diesel emulsion was experimentally investigated. Performance and emission characteristics of a diesel engine fuelled by BCO/diesel emulsion were examined. Results showed that stable engine operation was possible with emulsion and engine output power was comparable to diesel and bio diesel operation. Long term validation of adopting BCO in diesel engine is still needed because the oil is acid, with consequent problems of corrosion especially in the injection system.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.474-477
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• 2006

유동형 급속열분해기((fluidized bed type fast pyrolyzer, 용량 300g/h)를 이용하여 너도밤나무와 침엽수 흔합재(독일가문비나무/전나무, 50:50)로부터 바이오오일을 생산하였다. 목질바이오매스의 열분해는 약 $470{\pm}5^{\circ}C$에서 1-2초 간 진행되었다. 목질바이오매스의 열분해 생성물의 조성을 살펴보면, 너도밤나무는 바이오오일이 약 60%, 탄이 약 9% 피리 고 가스가 31% 가량 생산되었으며, 침엽수 혼합재는 49%의 바이오오일, 9%의 탄, 그리고 42% 가량의 가스가 생성되었다. 두 종류의 목질바이오매스에서 생산된 바이오오일에는 약 17-22% 가량의 수분이 포함되어 있었으며, 비중은 약 1.2kg/L 이었다. 바이오오일의 원소 조성은 탄소가 45%, 산소가 47% 수소가 7%, 그리 고 질소가 1% 로서 일반적 인 목질바이오매스와 큰 차이는 없는 것으로 나타났다. 그러나 화석자원에서 생산되는 오일류와 비교하여 산소함량은 매우 높았으나 황은 전혀 포함하고 있지 않았다. 바이오오일의 GC분석 결과 총 90여종의 고리형, 또는 비고리형 저분자량 화합물이 검출되었으며 이들의 함량은 바이오오일 전건중량의 31-33% 정도로 측정되었다.

• Proceedings of the Korea Forestry Energy Research Society Conference
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• 2011.02a
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• pp.45-48
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• 2011