• 한국연소학회지
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• 제16권1호
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• pp.8-14
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• 2011

Biomass gasification is a promising technology in terms of clean energy and flexible options for end use such as heat, steam, electricity, gaseous or liquid fuels. In a gasification process, reduction of tar is very important because it can cause any mechanical problems and small tar implies high energy efficiency. However, generation and conversion mechanisms of tar have not been fully understood due to its complex nature. In this study, characteristics of tar generated from different gasification stages were investigated. Korean pine woodchip was used as feedstock and tar was sampled in a separate way during devolatilization and char gasification stage, investigated. As a result. more various kinds of hydro carbon compounds were identified in the devolatilization stage than char gasification stage because primary tar compounds are released mostly from pyrolysis of cellulose and hemicellulose. When the reaction temperature increased up to $900^{\circ}C$, tar composition becomes simplified into about 10 aromatic compounds mostly with 1-4 rings without substitution up to phenanthrene. The sampled tar in the char gasification stage mostly contains 5-7 simple aromatic compounds.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.104.1-104.1
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• 2010

We investigated combustion characteristics of wood pellets in a combustion equipment with adjusting amount of flue gas. Maximum temperature in a combustion chamber was $850^{\circ}C$. Higher heating Value of a domestic wood pellet tested is 19.1 MJ/kg and water content was 8.3%. Amount of flue gas causes big effect on burning characteristics in $450{\sim}600^{\circ}C$. Wood pellet does not burn in low temperature atmosphere less than $450^{\circ}C$ and low flue gas flow rate. We made burning the pellet that is made in Korea, USA, Chile and Canada. Color of foreign pellets are bright brown and they made by mainly sawdust. Korean pellet is a dark brown color because it contains bark. There are some differences in the result of elementary analysis and technical analysis. According to the result of burning experiment, burning times of each countries's pellet are similar.

• 한국응용과학기술학회지
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• 제33권4호
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• pp.836-847
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• 2016

본 연구는 바이오매스를 열분해하여 생성된 수상오일(water soluble oil)을 얻었다. MDO(Marine Diesel Oil)와 수상오일을 유화시켜 생성된 에멀젼 연료의 특성과 배출가스를 연구 하였다. 바이오매스로는 톱밥을 사용하였고 $500^{\circ}C$에서 열분해하여 생성된 물과 탄화수소를 응축시켜서 수상오일을 얻었다. 수상오일을 MDO에 10~20% 까지 혼합 후 유화시켜 에멀젼 연료를 만들었다. 엔진 배출가스 측정은 엔진 dinamometer로 실시하였다. 유화연료는 연소실내에서 미세폭발을 일으켜 연료를 잘게 쪼개어 주어 smoke를 감소시킨다. 그리고 물이 연소실내의 기화열을 빼앗아 연소실 내부의 온도를 낮추어 NOx 생성을 억제하는 효과를 갖는다. ND-13모드의 각 모드별 배출가스온도가 MDO에 비해 유화연료를 사용했을 때 낮게 나온 것으로 뒷받침 될 수 있었다. 유화연료의 함수율이 증가함에 따라 NOx와 smoke의 배출량은 줄어들었으며, 출력도 함수율 증가에 따라 유화연료 자체의 발열량 감소로 인하여 줄어든 것으로 판단된다. ND-13모드에서 MDO 유화연료를 시험한 결과 바이오매스오일 함유량 20%인 유화연료의 NOx 감소량은 약 25%, smoke의 총감소량은 약 60%, 그리고 약 15%의 출력손실을 확인하였다.

• 한국응용과학기술학회지
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• 제35권4호
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• pp.1421-1432
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• 2018

본 연구에서는 바이오매스로서 코코넛 폐기물을 $600^{\circ}C$에서 열분해하여 생성된 수상오일(water soluble oil)을 얻었다. 선박유로 사용되는 MDO(Marine Diesel Oil)와 바이오매스로서 코코넛 폐기물을 열분해하여 생성된 수상오일을 MDO에 15~20% 까지 혼합 후 유화시켜 제조된 바이오에멀젼 연료의 연소 특성에 대하여 연구 하였다. 엔진 배출가스 및 온도, 출력을 측정하기 위하여 엔진 다이나모메터를 사용하였다. 바이오에멀젼 연료는 수분이 함유되어 있어서 연소실내의 기화잠열을 빼앗아가 배출가스의 온도를 낮춰주는 것으로 나타났다. 바이오에멀젼 연료에 함유된 수분이 연소실내에서 미세폭발을 일으켜 연료를 잘게 쪼개어 주어 매연을 감소시키는 것으로 나타났다. 바이오에멀젼 연료의 사용으로 연소실내의 온도 감소는 질소산화물 배출을 저감하는 것으로 나타났다. 바이오오일 함유량이 증가 하면 수분함량도 증가하여 전체 발열량이 줄어들게 된다. 따라서 출력이 바이오에멀젼 연료 사용량에 비례하여 감소하는 특성을 나타내었다. 선박용 연료로 사용되는 중질유는 매연과 질소산화물을 많이 배출한다. 선박용 연료로 바이오에멀젼 연료를 사용하면 매연과 질소산화물 배출을 줄여줄 수 있을 것으로 기대된다.

• 한국대기환경학회지
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• 제28권4호
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• pp.384-395
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• 2012

This study was performed to develop the source profiles for fine particles ($PM_{2.5}$) emitted from the biomass burning. The multi-method research strategy included a usage of combustion devices such as field burning, fireplace, and residential wood burning to burn rice straw, fallen leaves, pine tree, and oak tree. The data were collected from multiple sources and measured water-soluble ions, elements, elemental carbon (EC), and organic carbon (OC). From this study, it turned out that OC (34~67%) and EC (1.2~39%) are the major components emitted from biomass burning. In the case of burning rice straw at field burning, OC (66.6%) was the most abundant species, followed by EC (4.3%), $Cl^-$ (3.6%), Cl (2.1%), and $SO^{2-}_4$(1.9%). Burning rice straw, fallen leaves, pine tree, and oak tree at fireplace, the amount of OC was 58.5%, 52.7%, 52.5%, and 61.2%, and that of EC was 1.2%, 18.4%, 36.5%, and 2.7%, respectively. The ratio of OC for the burning of pine tree and oak tree from the residential wood burning device was 56.9% and 34.3%, and that of EC was 25% and 38.6%, respectively. Applying the measured data with respect to the proportion of components emitted from biomass burning to reference model, it turned out that self-diagnosed result was appropriate level, and the result based on the model is in highly corresponding to actual timing of biomass burning.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
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• pp.61-64
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• 2013

Biomass is well known for organic resources photosynthesized by carbon dioxide water in the air and thus it can be widely used in the form of energy and production for various kinds of materials. Through pyrolysis, biomass can be transformed into solid(biochar), liquid(bio-oil), and combustible gas on the different condition of temperature and heating rate. That's why biomass can be practically used to preprocess and produce a variety of elements. This work is to analyze the characteristics of slow pyrolysis of three different kinds of biomass extracted from Indonesia. They showed similar moisture content and combinations of combustible matters and had quite a large discrepancy in the ash among them like 2.1 & of Bagasse, 91% of PKS, and 20.9% of Paddy Straw, respectively. yield of biochar, solid form of the biomass, steadily decreased when the temperature went up and that of bio-oil the highest at the temperature of 500 degrees Celsius. At the same temperature range, PKS bio-oil showed 51.4 % of yield and Bagasse had 55.1% while it turned out that Paddy straw showed the lowest yield of 37.2%. The apparent density was also measured to figure out the density of each product from the pyrolysis experiments at the temperature of 500 degrees Celsius. The result was like these; the density of biochar was 0.17, the lowest, and that of Tree stem was 1.3 when mixed by an equal amount of biochar and bio-oil.

• 한국건축시공학회지
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• 제23권6호
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• pp.663-671
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• 2023

본 연구에서는 목질계 바이오매스(Bio-SRF, 우드펠릿)를 연료로 사용하는 발전소 3곳에서 배출된 4종의 목질계 플라이애시(FA)의 재활용성을 실험적으로 검토하였다. FA의 물리 분석(입형, 입도분포, 분말도, 밀도)과 화학 분석(화학조성, 중금속 함량)을 수행하였고, KS L 5405에 준하여 혼입률 5~20%의 모르타르 시험체를 제작하고 플로우와 압축강도를 측정하였다. 4종의 FA는 입경 약 20~30㎛, 밀도 약 2.3~2.5g/cm³, 분말도 2,600~4,900cm²/g, SiO₂, Al₂O₃, Fe₂O₃, CaO 성분이 약 50~90%를 차지하고 있으며, 염소와 SiO₂ 함량을 배제하고 KS L 5405의 FA 2, 3형과 유사한 특성을 보였다. 모르타르 혼입 평가 결과, 펠릿 연소 FA는 5~20% 혼입 범위에서 모르타르 압축강도는 34~47MPa로 측정되었다. 목질계 연료 100%를 연소한 FA는 혼화재 대체재로서 재활용성이 높다고 평가된다.

• 한국대기환경학회지
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• 제34권3호
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• pp.406-417
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• 2018

In this study, $PM_{2.5}$ samples were collected during approximately 3 years in Chuncheon, a small residential and tourist city, in Korea. The average $PM_{2.5}$ concentration was $26.9{\mu}g/m^3$, exceeding the annual national air quality standard. $PM_{2.5}$ showed typical seasonal variation, having higher concentration in winter and lower concentration in summer. Sixteen metallic elements in $PM_{2.5}$ were also analyzed, and K was the highest contributor especially in late fall and winter. In addition, K considerably increased for the top 10% of $PM_{2.5}$ samples and showed the highest correlation coefficient with $PM_{2.5}$ among all other metallic elements. These results suggest that the combustion of agricultural residue and other biomass, the major source of K was likely to be important to high $PM_{2.5}$ concentration events in this city. Crustal elements including Al, Fe, Si, Ti, Mg showed high concentration in spring while Cr, Cu and Ni were relatively consistent throughout a year. Principal component analysis was used to trace the sources, and soil re-suspension, combustion of biomass and fossil fuels, and asphalt concrete production were identified as the main sources of $PM_{2.5}$.

• 한국수소및신에너지학회논문집
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• 제30권6호
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• pp.567-577
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• 2019

Due to the depletion of fossil fuels and environmental pollution, demand for alternative energy is gradually increasing. Among the various methods, a method to convert biomass into alternative fuel has been proposed. The bio-fuel obtained from biomass through pyrolysis process is called pyrolysis oil (PO) or bio-oil. Because PO is difficult to use directly in conventional engines due to its poor fuel properties, various methods have been proposed to upgrade pyrolysis-oil. The simplest approach is to mix it with conventional fossil fuels. However, due to their different polarity of PO and fossil fuel, direct mixing is impossible. To resolve this problem, emulsification of two fuels with a proper surfactant was proposed, but it costs additional time and cost. Alternatively, the use of alcohol fuels as an organic solvent significantly improve the fuel properties such as fuel stability, calorific value and viscosity. In this study, blends of diesel, n-butanol, and coffee ground pyrolysis oil (CGPO) which is one of the promising PO, was applied to diesel generator. Combustion and emissions characteristics of blended fuels were investigated under the entire load range. Experimental results show that ignition delay is similar to that of diesel at high load. Although, hydrocarbon and carbon monoxide emissions are comparable to diesel, significant reduction of nitrogen oxides and particulate matter emissions were observed.

• Korean Chemical Engineering Research
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• 제59권1호
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• pp.127-137
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• 2021

미세먼지 전구체인 질소산화물(NOx)에 대한 대기배출부과금 제도가 2020년부터 국내에 도입 및 시행됨에 따라 이를 저감하기 위한 경제적인 연소기술 개발은 매우 시급한 실정이다. 본 연구에서는 해외 우드펠릿 대체재로서 REC(Renewable Energy Certificates) 확보가 가능한 국내 미이용 산림 바이오매스를 연료로 하여 0.1 MWth급 순환유동층 연소 설비에서 NOx 저감을 위한 air-staging 효과를 고찰하였다. 운전 변수로는 air-staging 적용 유무, 3차 공기 공급 높이(6.4 m, 8.1 m, 9.4 m) 그리고 air-staging 비율(1차 공기:2차 공기:3차 공기=91%:9%:0%, 82%:9%:9%, 73%:9%:18%) 변화이며 운전 변수에 대한 배기가스 내 NO와 CO 농도, 연소로 높이별 온도와 압력 프로파일, 포집된 비산재(fly ash) 내 미연탄소 함량과 연소효율을 분석하였다. 3차 공기를 가장 높은 9.4 m에서 공급한 air-staging 운전 시 NO 농도는 100.7 ppm으로 air-staging을 적용하지 않은 운전 조건(148.8 ppm)보다 32.3% 감소하지만 CO 농도는 오히려 52.2 ppm에서 99.8 ppm으로 91% 증가하였다. 더불어, NO 농도의 저감을 위한 환원영역과 CO 농도의 저감을 위한 산화영역 확보를 위해 3차 공기 공급 높이를 6.4 m로 유지하며 3차 공기 공급량을 늘리고 1차 공기 공급량을 낮춘 air-staging 운전 조건(73%:9%:18%)에서는 NO와 CO 농도가 각각 90.8 ppm과 66.1 ppm으로 air-staging 적용 조건 중 가장 감소되는 것을 확인하였다. 이러한 최적 운전 조건에서 연소효율 역시, air-staging을 적용하지 않은 운전 조건의 연소효율(98.3%) 보다 높은 99.3%임을 확인하였다.