Influence of additives on sodium release and ash sintering temperature of a high-alkali coal
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摘要: 选取三种不同的添加剂（高岭土、SiO2和Al2O3），研究它们对高碱准东煤钠迁移和灰分烧结温度的影响，并且添加比例为1%-5%。结果表明，三种添加剂的钠捕集效率依次为：高岭土> SiO2 > Al2O3。钠捕集效率随着添加比例的增加而升高，但受温度影响比较复杂。高岭土的钠捕集效率在600-1000℃先增加后减小，并在900℃达到最大值，其余两种随温度的升高均减小。准东煤灰的烧结温度为803℃，添加高岭土后，烧结温度随添加比例的增加先降低后上升。当添加比例为3%时，因为钙长石和钙黄长石的低温共熔反应而达到最小值。SiO2的添加比例为5%时，由于透辉石的生成和SiO2本身的"骨架"作用，烧结温度迅速升高到879℃。Al2O3对烧结温度的影响最小。Abstract: The influence of three additves (Kaolin, SiO2 and Al2O3) on sodium release and ash sintering temperature of high-alkali Zhundong coal with addition ratio range of 1%-5% was studied. The results indicate that the order of sodium capture efficiency for the additives is:Kaolin > SiO2 > Al2O3. The sodium capture efficiency increases with the addition ratio. However, the effect of temperature is much complex. At 600-1000℃, the sodium caputre efficiency of Kaolin increases firstly and then decreases, and the maximum value is achieved at 900℃. Meanwhile, the sodium capture efficiencies of other two additives decrease with increasing temperature. In addition, the ash sintering temperature of Zhundong coal is 803℃. After adding Kaolin, it decreases firstly and then increases with the addition ratio. At the addition ratio of 3%, the sintering tempeature is lowest due to the low-melting eutectic reaction between gehlenite and anorthite. SiO2 with 5% can increase the sinntering temperature to 879℃ sharply because of generation of diopside and its skeleton effect. The influence of Al2O3 on the sintering temperature is minimal.
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Key words:
- Zhundong coal /
- additive /
- sodium capture efficiency /
- sintering temperature /
- mineral evolution
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图 2 压差法烧结温度测量系统图
Figure 2 Schematic of sintering temperature measurement with pressure-drop method
1: air cylinder; 2: mass flow controller; 3: pressure-drop transmitter; 4: reactor tube; 5: ash pellet; 6: data logger; 7: thermocouple; 8: tube furnace
图 3 900 ℃时不同添加剂的钠捕集效率
Figure 3 Sodium capture efficiencies of different additives at 900 ℃
图 4 不同燃烧温度时的钠捕集效率
Figure 4 Sodium capture efficiencies at different temperatures (addition ratio: 5%)
图 6 添加高岭土后烧结灰柱的XRD谱图
Figure 6 XRD patterns of sintered ash pellets after adding Kaolin
1: quartz (SiO2); 2: anhydrite (CaSO4); 3: nepheline (Na2O·Al2O3·2SiO2); 4: gehlenite (2CaO·Al2O3·SiO2); 5: hematite (Fe2O3); 6: hauynite (Na6Ca2Al6Si6O24(SO4)2); 7: calcium aluminum silicon (CaAl2Si2); 8: anorthite (CaO·Al2O3·2SiO2)
图 7 添加SiO2后烧结灰柱的XRD谱图
Figure 7 XRD patterns of sintered ash pellets after adding SiO2
1: quartz (SiO2); 2: anhydrite (CaSO4); 3: nepheline (Na2O·Al2O3·2SiO2); 4: gehlenite (2CaO·Al2O3·SiO2); 5: hematite (Fe2O3); 6: hauynite (Na6Ca2Al6Si6O24(SO4)2); 7: diopside (CaO·MgO·2SiO2)
图 8 添加Al2O3后烧结灰柱的XRD谱图
Figure 8 XRD patterns of sintered ash pellets after adding Al2O3
1: quartz (SiO2); 2: anhydrite (CaSO4); 3: nepheline (Na2O·Al2O3·2SiO2); 4: gehlenite (2CaO·Al2O3·SiO2); 5: hematite (Fe2O3); 6: aluminum oxide (Al2O3)
表 1 准东煤的工业分析与元素分析
Table 1 Proximate and ultimate analyses of Zhundong coal
Proximate analysis wad/% Ultimate analysis wad/% M A V FC C H O N St Cl 11.17 6.43 27.91 54.49 62.89 3.04 15.41 0.55 0.51 0.02 
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表 2 准东煤的灰成分分析
Table 2 Ash composition analysis of Zhundong coal
Content w/% SiO2 Al2O3 Fe2O3 CaO MgO K2O Na2O SO3 41.57 11.16 4.79 16.21 6.48 0.51 3.50 8.05
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[1] 李路明.燃烧新疆准东煤350 MW超临界锅炉设计应用[J].电站系统工程, 2014, 30(2):39-41. http://www.cqvip.com/QK/94652X/201402/49131621.htmlLI Lu-ming. Design and application of 350 MW supercritical boiler burning Zhundong coal[J]. Pow Syst Eng, 2014, 30(2):39-41. http://www.cqvip.com/QK/94652X/201402/49131621.html [2] 王学斌, 魏博, 张利孟, 谭厚章, 徐通模.温度和SiO2添加物对准东煤中碱金属的赋存形态及迁徙特性的影响[J].热力发电, 2014, 43(8):84-88. doi: 10.3969/j.issn.1002-3364.2014.08.084WANG Xue-bin, WEI Bo, ZHANG Li-meng, TAN Hou-zhang, XU Tong-mo. Effect of temperature and silicon additives on occurrence and transformation characteristics of alkali metal in Zhundong coal[J]. Therm Pow Gen, 2014, 43(8):84-88. doi: 10.3969/j.issn.1002-3364.2014.08.084 [3] XU L, KANG Y, ZHANG G, WANG T, WU T. Study of alkali emission and control with firing a high alkali coal[J]. Combust Sci Technol, 2015, 187(12):1959-1973. doi: 10.1080/00102202.2015.1069283 [4] 沈铭科, 邱坤赞, 黄镇宇, 王智化, 刘建忠.准东煤掺烧高岭土对固钠率及灰熔融特性影响研究[J].燃料化学学报, 2015, 43(9):1044-1051. doi: 10.3969/j.issn.0253-2409.2015.09.004SHEN Ming-ke, QIU Kun-zan, HUANG Zhen-yu, WANG Zhi-hua, LIU Jian-zhong. Influence of Kaolin on sodium retention and ash fusion characteristic during combustion of Zhundong coal[J]. J Fuel Chem Technol, 2015, 43(9):1044-1051. doi: 10.3969/j.issn.0253-2409.2015.09.004 [5] WEI B, WANG X, TAN H, ZHANG L, WANG Y, WANG Z. Effect of silicon-aluminum additives on ash fusion and ash mineral conversion of Xinjiang high-sodium coal[J]. Fuel, 2016, 181:1224-1229. doi: 10.1016/j.fuel.2016.02.072 [6] 陈午凤, 王长安, 魏邓昶泓, 延禹, 靳熹, 张远航, 车得福.准东煤O2/CO2燃烧过程中硅铝矿物添加剂对钠/钙/铁释放与迁移的影响[J].新能源进展, 2017, 5(1):16-22. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=xnyjz201701003CHEN Wu-feng, WANG Chang-an, WEI Deng-chang-hong, YAN Yu, JIN Xi, ZHANG Yuan-hang, CHE De-fu. Influence of salic mineral additives on release and migration of Na/Ca/Fe during O2/CO2 combustion of Zhundong coals[J]. Adv New Renewable Energy, 2017, 5(1):16-22. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=xnyjz201701003 [7] 涂圣康, 张守玉, 施大钟, 金涛, 杨靖宁, 刘大海, 裴育峰.添加剂对高钠煤热解过程中钠析出的影响[J].煤炭转化, 2016, 39(1):31-34. doi: 10.3969/j.issn.1004-4248.2016.01.007TU Sheng-kang, ZHANG Shou-yu, SHI Da-zhong, JIN Tao, YANG Jing-ning, LIU Da-hai, PEI Yu-feng. Effect of additive on emission of sodium in high-sodium coal during pyrolysis[J]. Coal Convers, 2016, 39(1):31-34. doi: 10.3969/j.issn.1004-4248.2016.01.007 [8] NAMKUNG H, XU L, KIM C H, YUAN X, KANG T, KIM H. Effect of mineral components on sintering of ash particles at low temperature fouling conditions[J]. Fuel Process Technol, 2016, 141:82-92. doi: 10.1016/j.fuproc.2015.06.004 [9] 王勤辉, 揭涛, 李小敏, 骆仲泱, 景妮洁, 岑可法.反应气氛对不同煤灰烧结温度影响的研究[J].燃料化学学报, 2010, 38(1):17-22. doi: 10.3969/j.issn.0253-2409.2010.01.004WANG Qin-hui, JIE Tao, LI Xiao-min, LUO Zhong-yang, JING Ni-jie, CEN Ke-fa. Experimental of the effects of reaction atmosphere on the coal ash sintering temperature[J]. J Fuel Chem Technol, 2010, 38(1):17-22. doi: 10.3969/j.issn.0253-2409.2010.01.004 [10] ABD-ELHADY M S, CLEVERS S H, ADRIAANS T N G, RINDT C C M, WIJERS J G, VAN STEENHOVEN A A. Influence of sintering on the growth rate of particulate fouling layers[J]. Int J Heat Mass Transfer, 2007, 50(1/2):196-207. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=JJ023524981 [11] TONMUKAYAKUL N, NGUYEN Q D. A new rheometer for direct measurement of the flow properties of coal ash at high temperaturesq[J]. Fuel, 2002, 81(4):397-404. doi: 10.1016/S0016-2361(01)00175-2 [12] RAASK E. Mineral Impurities In Coal Combustion[M]. Washington:Hemisphere Publishing Corporation, 1985. [13] LUAN C, YOU C, ZHANG D. Composition and sintering characteristics of ashes from co-firing of coal and biomass in a laboratory-scale drop tube furnace[J]. Energy, 2014, 69:562-570. doi: 10.1016/j.energy.2014.03.050 [14] LLORENTE M J F, AROCAS P D, NEBOT L G, GARCÍA J E C. The effect of the addition of chemical materials on the sintering of biomass ash[J]. Fuel, 2008, 87(12):2651-2658. doi: 10.1016/j.fuel.2008.02.019 [15] WANG L, SKREIBERG Ø, BECIDAN M. Investigation of additives for preventing ash fouling and sintering during barley straw combustion[J]. Appl Therm Eng, 2014, 70(2):1262-1269. doi: 10.1016/j.applthermaleng.2014.05.075 [16] SELVAKUMARAN P, LAWERENCE A, BAKTHAVATSALAM A K. Effect of additives on sintering of lignites during CFB combustion[J]. Appl Therm Eng, 2014, 67(1/2):480-488. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=JJ0232843342 [17] LIU Y, CHENG L, ZHAO Y, JI J, WANG Q, LUO Z, BAI Y. Transformation behavior of alkali metals in high-alkali coals[J]. Fuel Process Technol, 2018, 169:288-294. doi: 10.1016/j.fuproc.2017.09.013 [18] 刘炎泉, 程乐鸣, 季杰强, 张维国, 王勤辉, 周棋, 聂立.准东煤燃烧碱金属析出气、固相分布特性[J].燃料化学学报, 2016, 44(3):314-320. doi: 10.3969/j.issn.0253-2409.2016.03.008LIU Yan-quan, CHEN Le-ming, JI Jie-qiang, ZHANG Wei-guo, WANG Qin-hui, ZHOU Qi, NIE Li. Distribution characteristics of alkali emission between gas and solid phase during Zhundong coal combustion[J]. J Fuel Chem Technol, 2016, 44(3):314-320. doi: 10.3969/j.issn.0253-2409.2016.03.008 [19] WANG X, XU Z, WEI B, ZHANG L, TAN H, YANG T, MIKULČIĆ H, DUIĆ N. The ash deposition mechanism in boilers burning Zhundong coal with high contents of sodium and calcium:A study from ash evaporating to condensing[J]. Appl Therm Eng, 2015, 80(5):150-159. http://www.sciencedirect.com/science/article/pii/S1359431115000654 [20] SONG G, SONG W, QI X, LU Q. Transformation characteristics of sodium of Zhundong coal combustion/gasification in circulating fluidized bed[J]. Energy Fuels, 2016, 30(4):3473-3478. doi: 10.1021/acs.energyfuels.6b00028 [21] KOSMINSKI A, ROSS D P, AGNEW J B. Reactions between sodium and Kaolin during gasification of a low-rank coal[J]. Fuel Process Technol, 2006, 87(12):1051-1062. doi: 10.1016/j.fuproc.2005.06.004 [22] KYI S, CHADWICK B L. Screening of potential mineral additives for use as fouling preventatives in Victorian brown coal combustion[J]. Fuel, 1999, 78(7):845-855. doi: 10.1016/S0016-2361(98)00205-1 [23] 张利孟, 董信光, 刘科, 谭厚章, 王学斌, 魏博.高岭土对准东煤结渣特性及矿物质演变的影响[J].燃料化学学报, 2015, 43(10):1176-1181. doi: 10.3969/j.issn.0253-2409.2015.10.004ZHANG Li-meng, DONG Xin-guang, LIU Ke, TAN Hou-zhang, WANG Xue-bin, WEI Bo. Effect of Kaolin on ash slagging and mineral conversion of Zhundong coal[J]. J Fuel Chem Technol, 2015, 43(10):1176-1181. doi: 10.3969/j.issn.0253-2409.2015.10.004 [24] QIU J R, LI F, ZHENG Y, ZHENG C G, ZHOU H C. The influences of mineral behaviour on blended coal ash fusion characteristics[J]. Fuel, 1999, 78(8):963-969. doi: 10.1016/S0016-2361(99)00005-8 -
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