| Energy and Enviromental Engineering |
|
|
|
|
| characteristic of Shenhua coal ash blending with saw dust ash in O2/CO2 atmosphere |
| ZHOU Bin, ZHOU Hao, WANG Jian yang, CEN Ke fa |
| State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China |
|
|
|
Abstract CCD monitoring system and sintering probe were applied to investigate the sintering characteristic of Shenhua coal ash blending with saw dust ash in oxy fuel combustion atmosphere (O2/CO2). The shape of ash samples was observed online by the CCD monitoring system. The results reveal that the effect of the blending ratio of saw dust ash on the height of ash sample was not evident. Nevertheless, the blending ratio of saw dust ash affects the cross sectional area of ash sample significantly. The height shrinkage rates of the ash samples were 0.127, 0.119, 0.134, 0.124 and 0.136, which corresponding to 0%, 25%, 50%, 75% and 100% of saw dust ash in blend ash. And the corresponding area shrinkage rates were 0.125, 0.150, 0.074, 0.117 and 0.164, respectively. Meanwhile, results indicate that all the residue ashes are characterized by three layer structures with different colors and sintering degrees. The XRD analysis results show that the blending ratio of saw dust ash in the blend ash influence the types and content of mineral in the residue ashes, especially for the outer most layer. The SEM analysis results reveal that the blending saw dust ash in blend ash can give rise to the smaller of pore structures in the outer most layer. In addition, the saw dust ash can make the matrix of the outer most layer more smooth and compact．
|
|
Published: 18 September 2016
|
|
|
神华煤灰掺混木屑灰在O2/CO2气氛下的烧结特性
利用CCD监测系统和自制烧结探针研究神华煤灰掺混不同比例的木屑灰在O2/CO2气氛下的烧结特征,实时在线监测灰块在烧结时的形状特征.结果表明：掺混木屑灰对混合灰块的高度影响较少,而对横截面积影响较大.当木屑灰比例为0、25%、50%、75%和100%时,相应的高度收缩率分别为0.127、0.119、0.134、0.124和0.136,而横截面积收缩率则分别为0.125、0.150、0.074、0.117和0.164.各灰块在烧结探针上经过烧结处理后,其横截面都具有三层层状结构,且每层的颜色和烧结程度都不同.利用XRD技术对每层的矿物质分布进行分析,结果表明：对于掺混不同比例的生物质灰,其混合灰块的矿物质种类和含量都有很大变化,尤其是最外层.对各灰块的层状结构进行SEM分析,发现掺入木屑灰后,灰块最外层孔状结构变小.同时,加入掺混木屑灰能够使得灰块最外层的横截面结构光滑致密.
|
|
| ［1］ WALL T, LIU Y, SPERO C, et al. An overview on oxyfuel coal combustion state of the art research and technology development ［J］. Chemical Engineering Research and Design, 2009, 87(8A): 10031016.
［2］ BUHRE B, ELLIOTT L, SHENG C, et al. Oxy fuel combustion technology for coal fired power generation[J].Progress in Energy and Combustion Science, 2005, 31(4): 283307．
［3］ ANDERSSON K, JOHNSSON F. Process evaluation of an 865MWe lignite fired O2/CO2 power plant ［J］.Energy Conversion and Management,2006, 47(18): 34873498．
［4］ CHEN Y, WANG G, SHENG C. Comparison of particle size evolution during pulverized coal combustion in O2/CO2 and O2/N2 atmosphere [J]. Energy Fuels, 2014, 28(1): 136145．
［5］ SHENG C, LU Y, GAO X, YAO H. Fine ash formation during pulverized coal combustion:a comparison of O2/CO2 combustion versus air combustion ［J］. Energy and Fuels,2007, 21(2): 435440．
［6］ NSAKALA N Y, MARION J, BOZZUTO C, et al. Engineering feasibility of CO2 capture on existing U.S. coal fired power plant ［C］∥First National Conference on Carbon Sequestration. Washington DC: ［s.n.］, 2001．
［7］ SINGH D, CROISET E, DOUGLAS P, et al. Techno economic study of CO2 capture from an existing coal fired power plant: MEA scrubbing versus O2/CO2 recycle combustion ［J］. Energy Conversion and Management,2003, 44(19): 30733091．
［8］ BEJARANO P, LEVENDIS Y. Single coal particle combustion in O2/N2 and O2/CO2 environments ［J］. Combustion and Flame, 2008, 153(1/2): 270287．
［9］ CROISET E, THAMBIMUTHU K. NOx and SO2 emission from O2/CO2 recycled coal combustion ［J］. Fuel,2001, 80(14): 21172121．
［10］ BORREGO A, ALVAREZ D. Comparison of chars obtained under oxy fuel and conventional pulverized coal combustion atmospheres ［J］. Energy Fuels, 2207, 21(6): 31733179．
［11］ SCHEFFKNECHT G, MAKHADMEH L, SCHNELL U, et al. Oxy fuel coal combustion:a review of the current state of the art ［J］. International Journal of Greenhouse Gas Control,2011, 55(1): 516535．
［12］ ZENG Z, NATESAN K, CAI Z, et al. Effect of coal ash on the performance of alloys in simulated oxy fuel environments ［J］.Fuel, 2014, 117(A): 133145．
［13］ LIU H, ZAILANI R, GIBBS B. Comparisons of pulverized coal combustion in air and in mixtures of O2/CO2 ［J］. Fuel, 2005, 84(7/8): 833840．
［14］ CROISET E, THAMBIMUTHU K. NOx and SO2 emissions from O2/CO2 recycle coal combustion ［J］. Fuel,2001, 80(14): 21172121．
［15］ BOLEA I, ROMEO L, PALLARS D. Heat transfer in the external heat exchanger of oxy fuel fluidized bed boilers ［J］. Applied Thermal Engineering, 2014, 66(1/2): 7583．
［16］ LIU Y, GEIER M, MOLINA A, et al. Pulverized coal stream ignition delay under conventional and oxy fuel combustion conditions ［J］. International Journal of Greenhouse Gas Control, 2011, 5(1): S36S46．
［17］ LI G, LI S, DONG M, et al. Comparison of particulate formation and ash deposition under oxy fuel and conventional pulverized coal combustions ［J］. Fuel, 2013, 106: 544551．
［18］ CHEN Y, WANG G, SHENG C. Comparison of particle size evolution during pulverized coal combustion in O2/CO2 and O2/N2 atmospheres ［J］. Energy and Fuels, 2014, 28(1): 136145．
［19］ 陈雪莉,刘涛,刘霞,等. 掺混生物质对煤灰熔点的影响及混合灰流动温度的预测［J］.中国电机工程学报， 2012, 32（11）, 4146．
CHEN Xue Li, LIU Tao, LIU Xia, et al. Effects of crop straw on coal ash fusion temperature and prediction of blend ash fusion temperature ［J］. Proceedings of the CSEE, 2012, 32（11）, 4146．
［20］ 蒲舸,谭波. 生物质和高硫劣质煤混烧灰熔融特性研究［J］. 中国电机工程学报. 2011, 31（23）, 108114．
PU Ge, TAN Bo. Study on fusion characteristics of ash produced by co combustion biomass and high sulfur low grade coal ［J］. Proceedings of the CSEE,2011, 31（23）, 108114.
［21］ 董信光, 李荣玉,刘志超,等. 生物质与煤混燃的灰分特性分析［J］. 中国电机工程学报. 2009, 29（26）, 118124．
DONG Xin guang, LI Rong yu, LIU Zhi chao, et al. Investigation on the ash characteristic during co firing of coal and biomass ［J］. Proceedings of the CSEE. 2009, 29（26）, 118124.
［22］ 徐婧, 余春江, 秦建光,等. 麦草木素与煤混烧灰熔融特性［J］. 浙江大学学报:工学版, 2007, 41（7）, 11861190．
XU Jing, YU Chun jiang, QIN Jian guang, et al. Ash fusion characteristics of wheat straw lignin and coal co combustion ［J］. Journal of Zhejiang University:Engineering Science, 2007, 41（7）, 11861190．
［23］ ARVELAKIS S, FOLKEDAHL B, DAM K, et al.Studying the melting behavior of coal, biomass, and coal/biomass ash using viscosity and heated stage XRD data ［J］. Energy and Fuels, 2006, 20(3): 13291340．
［24］ VAMVUKA D,PITHAROULIS M,ALEVIZOS G,et al.Ash effects during combustion of lignite/biomass blends in fluidized bed ［J］.Renewable Energy,2009,34(12)：26622671．
［25］ ZHENG Y, JENSEN P, JENSEN A, et al.Ash transformation during co firing coal and straw ［J］.Fuel, 2007, 86(7/8): 10081020．
［26］ ZHOU H, ZHOU B, DONG K, et al. Research on the slagging characteristics of easy to slagging coal in a pilot scale furnace ［J］. Fuel, 2013, 109: 608615. |
|
Viewed |
|
|
|
Full text
|
|
|
|
|
Abstract
|
|
|
|
|
Cited |
|
|
|
|
| |
Shared |
|
|
|
|
| |
Discussed |
|
|
|
|
