• 제목/요약/키워드: Pulverized Coal Combustion

검색결과 124건 처리시간 0.029초

동시계측에 의한 난류 미분탄 화염의 순간구조에 관한 연구 (Study on Instantaneous Structure of Turbulent Pulverized Coal Flame by Simultaneous Measurement)

  • 황승민
    • 한국환경과학회지
    • /
    • 제27권5호
    • /
    • pp.309-317
    • /
    • 2018
  • In this study, a laser sheet technique and PLIF (Planar laser-induced fluorescence) are applied to a laboratory-scale pulverized coal burner of the open type, and the spatial relationship of the pulverized coal particle zone and the combustion reaction zone is examined by simultaneous measurement of Mie scattering and OH-LIF images. It is found that this technique can be used to investigate the spatial relationship of the combustion reaction zone and pulverized-coal particles in turbulent pulverized-coal flames without disturbing the combustion reaction field. In the upstream region, the combustion reaction occurs only in the periphery of the clusters where high-temperature burned gas of the methane pilot flame is entrained and oxygen supply is sufficient. In the downstream region, however, combustion reaction can be seen also within clusters of pulverized-coal particles, since the temperature of pulverized-coal particles rises, and the mixing with emitted volatile matter and ambient air is promoted.

연소중 미분탄의 발광 분석 및 입자 채집 관찰 (Experimental Investigation of Burning Pulverized Coal Particles: Emission Analysis and Observation of Particle Sample)

  • 김대희;최상민
    • 한국연소학회지
    • /
    • 제15권2호
    • /
    • pp.19-26
    • /
    • 2010
  • Combustion behavior of pulverized coal particles in a post-combustion gas reactor was investigated. Radiation emission from coal particles were analyzed by direct photograph and $CH^*$ radical chemiluminescence intensity. Coal particles were sampled during the combustion and were observed by scanning electron microscopy (SEM) and cross section micrograpy technique. Two coal types(one bituminous and one subbituminous coals typically used in the Korean power plants) were tested at typical combustion environment. Gas flow conditions were controlled to represent temperature and oxygen concentration. Experimental data were discussed along with conceptual descriptions of pulverized coal combustion, where particle heat-up, release and combustion of volatiles, and char combustion were sequentially progressed.

미분탄 연소에 따른 슬래깅 예측 모델 개발 및 검증 (Prediction of ash deposition propensity in a pilot-scaled pulverized coal combustion)

  • 장권우;한가람;허강열;박호영
    • 한국연소학회:학술대회논문집
    • /
    • 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
    • /
    • pp.87-90
    • /
    • 2013
  • In pulverized coal fired boilers, slagging and fouling may cause significant effect on the operational life of boiler. As increasing a consumption of low rank coal, slagging and fouling are main issues in pulverized coal combustion. This study predicts ash deposition propensity in a 0.7 MW pilot-scale furnace. Slagging model is employed as a User-Defined Function (UDF) of FLUENT and validated against measurement and prediction. The results show good agreement compared with experiment. There is need to development of a pulverized coal combustion and slagging analysis at low coal.

  • PDF

미분탄 연소의 점화 특성에 관한 연구 (Ignition behaviour of pulverized coal particle during coal combustion)

  • 이동방;김량균;송주헌;전충환
    • 한국연소학회:학술대회논문집
    • /
    • 한국연소학회 2012년도 제44회 KOSCO SYMPOSIUM 초록집
    • /
    • pp.213-215
    • /
    • 2012
  • As one of the primary fuel sources, oxy-fuel combustion of coal is actively being investigated because of the climate changing problem such like the emission of green house gases. In this paper research about the pulverized coal technology, which is widely used in both power-generating and iron-making processes was studied to invesgate the ignition behaviour of pulverized coal particles during coal combustion as changing the ambient oxygen concentration of the particle. The ignition phenomenon of the coal particles fed into a laminar flow reactor was imaged with a Integrated charged-coupled device (ICCD) camera. The ignition points were determined throught the analysis of the images, and then the ignition delay times were able to be calculated. The experiment results show that a lower oxygen concentration increases the ignition delay time.

  • PDF

미분탄 화력발전소 연료로서 고수분 인도네시아탄의 연소특성 (Combustion Characteristics of High Moisture Indonesia Coal as a Pulverized Fuel at Thermal Power Plant)

  • 김재관;이현동
    • 한국연소학회지
    • /
    • 제14권3호
    • /
    • pp.16-23
    • /
    • 2009
  • It is strongly desired for coal-fired power plants to utilize not only low-rank coals with high moisture contents, but also lowering cost with diversifying fuel sources. In this study, combustion characteristics of low rank coal with high moisture, and standard pulverized coals are experimentally investigated using TGA (Thermogravimetric Analysis) and DTF (drop tube furnace). The coals tested are three kinds of coal with moisture content ranging from 8.32 to 26.82%. The results show that under the air combustion condition, the burn-out time at TGA rises as moisture content increases, and standard pulverized coal with 8.32% moisture content showed the lowest activation energy of 55.73 kJ/mol. In case of the high amount of moisture, the combustion efficiency decreases due to evaporation heat loss, and unburned carbon in ash produced at combustion process in DTF increased. Aslo, initial deformation temperature of slag attached in alumina tube of DTF decreased with lowering the crytallinity of anorthite and augite. To improve the combustion reactivity and efficiency, it is effective to upgrade through drying the high moisture coal to moisture level (less than 10%) of standard pulverized coal.

  • PDF

고로의 연소효율을 높이기 위한 미분탄 공급 시스템 개발 (Pulverized coal injection system development to raise combustion efficiencies of a blast furnace)

  • 안영진;강법성;곽남수;최경민;이민철
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2008년도 추계학술대회B
    • /
    • pp.3163-3168
    • /
    • 2008
  • Pulverized coal (PC) has become an important auxiliary fuel in the iron and steel industry since the technique of pulverized coal injection (PCI) system was developed for iron making. Combustion efficiencies of pulverized coal in blowpipes and tuyeres under various operational are numerically predicted to recognize the performance with the locations of nozzles in a blast furnace. A variety of parameters including the pulverized coal quantities, oxygen amounts, inlet temperature of the tuyeres and mass flow rate of coal carrier gas are taken into consideration. Also In order to develop more efficient than existing coal injection system, this study applies a flame measurement system using a charge couple device (CCD) camera and frame grabber. And it has used algorithms of auto sampling from flame shape information and composed the device for location control of PCI. This study find to further improve the blast furnace performance by the control of PCI locations.

  • PDF

연소중 미분탄의 단면관측 (Cross-section micrography of burning pulverized coal particles)

  • 한재현;최상민
    • 대한기계학회논문집
    • /
    • 제13권4호
    • /
    • pp.717-725
    • /
    • 1989
  • 본 연구에서는 미분탄의 연소과정을 파악하기 위하여 메탄-공기 예혼합 화염에서 연소중인 석탄입자를 단계별로 여러 위치에서 순간 냉각에 의해 채취한 후 단면을 관측함으로써 미분탄 연소과정의 해석을 시도하였다. 산소 함유량이 미분탄 연소에 미치는 영향을 고려하기 위하여 반응로에서의 연소 조건을 바꾸어 보았다. 또한 미분탄 연소과정의 이해를 돕기 위해 비분탄을 도가니에 넣어 전기 로에서 가열하여 얻은 챠르와 공기중에서 가열하여 얻은 회(ash)에 대한 단면을 관측하였다. 시험용 미분탄은 국내 발전소 등지에서 대량 소비되는 수입 유연탄을 사용하였다.

2단 동축형 Cyclone 연소기를 이용한 저공해 미분탄 연소특성 연구 (A Study on Low Emission Pulverized Coal Combustion in the 2 Staged Coaxial Cyclone Combustor)

  • 최상일;박주식;김성완;김호영
    • 한국연소학회지
    • /
    • 제4권1호
    • /
    • pp.67-83
    • /
    • 1999
  • The objective of this study is development of low emission pulverized coal combustor for reducing pollutant emission generated from coal combustion. Low emission combustion technology for reducing NOx and fly ash was investigated by using 2 stage coaxial cyclone combustor. Staged combustion was employed for NOx reduction and high temperature slagging combustion was also studied for fly ash removal in the combustor. The result of this study shows that the low emission combustion system can reduce the amount of atmospheric pollutions with improved boiler efficiency and performance.

  • PDF

탈휘발 예측 코드를 활용한 탈휘발 및 촤반응 모델 평가 (Evaluation of the Structural Coal Combustion Model in a Swirling Pulverized Coal Combustor)

  • 정대로;한가람;허강열;박호영
    • 한국연소학회지
    • /
    • 제17권2호
    • /
    • pp.32-39
    • /
    • 2012
  • In this study, pre-processor code based on structural behavior of coal is applied to predict yields, pyrolysis rate and compositions of volatile and char. These parameters are used in the devolatilization and char burnout sub-models as user-defined functions of commercial CFD code. The predicted characteristics of these sub-models are compared with those employing the conventional model based on experiment and validated against the measurement of a 2.1 MW swirling pulverized coal flame in a semi-industrial scale furnace. And the influence of the turbulence-chemistry interaction on pulverized coal combustion is analyzed.

미분탄 순산소 연소에서 주위 기체와 석탄 특성이 화염전파에 미치는 영향 (Influence of Surrounding Gas and Coal Characteristics on Flame Propagation in Oxy-Fuel Combustion of Pulverized Coal)

  • 강영민;심영삼;문철언;성연모;서상일;김태형;최경민;김덕줄
    • 대한기계학회논문집B
    • /
    • 제33권1호
    • /
    • pp.38-45
    • /
    • 2009
  • Oxy-fuel combustion of pulverized coal is one of the promising new technologies to reduce $CO_2$ and NOx from coal combustion. However, the stability of pulverized coal flame is reduced in the oxy-fuel combustion. This flame stability is concerned with the flame propagation that is affected by surrounding gas and coal characteristics, such as gas temperature, gas composition, coal volatile, coal activation energy and coal size. In this paper, a study on the influence of surrounding gas and coal characteristics on the flame propagation velocity in oxy-fuel combustion of pulverized coal was preformed. One dimensional model was used to calculate the flame propagation velocity of pulverized coal clouds. In this model, the radiation is considered to be the main source of heat exchange, and Monte Carlo method was adopted for accurate calculation of radiation heat flux. It was found that the flame propagation velocity become higher with the decrease of coal activation energy and the increase of coal volatile. Also, according to the increase of gas temperature and $O_2$ concentration, flame propagation velocity increased.