Study on effect of Shanxi high ash content and ash fusion temperature coals on fluxing mechanism of limestone
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摘要: 以山西"两高"煤为研究对象,考察了洗选改变灰分对添加助熔剂CaCO3的影响。研究发现,随着洗煤灰分的降低,煤灰中二氧化硅含量及硅铝比(Si/Al)降低,煤灰流动温度降低至液态排渣气流床气化所需温度时,CaCO3的添加比例与洗煤高温下生成的矿物质种类及其含量相关,经过洗选降低灰分后的FH与SH洗煤,通过添加一定比例的助熔剂CaCO3,高温下煤灰渣类型由结晶渣变为玻璃体渣,排渣温度范围宽,能够很好地满足气流床气化液态排渣的要求,洗选与添加CaCO3助熔剂配合使用的方式,可以有效调控山西"两高"煤灰流动性质。Abstract: The floated coal samples with different ash contents were obtained by coal washing, and the effect of ash content on addition of fluxing CaCO3 was investigated. The results show that silica content and silicon to aluminum ratio (Si/Al) of ash decrease with decreasing ash content. The AFTs of coal ashes change with increasing CaCO3 addition. The additive CaCO3 content is closely related to the mineral formed at high temperatures and their contents. Furthermore, for the FH and SH coals after floatation, the viscosity of slag with CaCO3 addition exhibits a behavior of glass slag, and also has a large slagging temperature range. The properties of the floated coal ash slags with CaCO3 addition well meet the requirement of slag tapping in entrained flow gasifier. It is an effective way for Shanxi high ash content and ash fusion temperature coals to combine coal washing and CaCO3 adding to adjust the ash flow properties in entrained flow gasification.
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表 1 煤样的工业分析和元素分析
Table 1 Proximate and ultimate analysis of coals
Sample Proximate analysis wad/% Ultimate analysis wad/% M A V FC C H O* N St FH 3.72 31.72 5.61 58.95 54.27 1.96 3.78 0.66 3.89 SH 3.60 41.67 5.54 49.19 47.49 1.81 3.20 0.54 1.69 O*: by diffidence; St: total sulfur 表 2 煤样的灰成分分析
Table 2 Chemical compositions of coal ashes
Sample Content w/% Si/Al SiO2 Al2O3 Fe2O3 CaO MgO SO3 K2O Na2O FH 52.37 26.45 13.21 2.69 0.63 1.13 1.37 0.71 1.98 SH 56.88 29.92 5.35 2.70 0.66 0.78 1.49 0.86 1.90 表 3 煤样的灰熔融性特征温度
Table 3 Coal ash fusion temperatures
Sample Temperature t/℃ DT ST HT FT FH 1 347 1 384 1 398 1 421 SH 1 480 1 517 1 528 1 542 DT: deformation temperature; ST: sphere temperature;
HT: hemisphere temperature; FT: flow temperature -
[1] 于遵宏, 王辅臣.煤炭气化技术[M].北京:化学工业出版社, 2013.YU Zun-hong, WANG Fu-chen. Coal Gasification Technol[M]. Beijing:Chemical Industry Press, 2013. [2] 张绍韡.论山西省无烟煤及动力煤资源量的现状、分布及预测[J].华北国土资源, 2014, (2):108-111. http://kns.cnki.net/KCMS/detail/detail.aspx?filename=hbgt201402091&dbname=CJFD&dbcode=CJFQZHANG Shao-wei. The quantity, distribution and forecast of the anthracite coal and steam coal from Shanxi[J]. Huabei Land Resources, 2014, (2):108-111. http://kns.cnki.net/KCMS/detail/detail.aspx?filename=hbgt201402091&dbname=CJFD&dbcode=CJFQ [3] GB/T 29722-2013, 气流床气化用原料煤技术条件[S].GB/T 29722-2013, Specifications of coal for entrained-flow gasifier[S]. [4] 李文, 白进.煤的灰化学[M].北京:科学出版社, 2013.LI Wen, BAI Jin. Coal Ash Chemistry[M]. Beijing:Science Press, 2013. [5] 陈清如, 骆振福.干法选煤评述[J].选煤技术, 2003, (6):34-40. http://kns.cnki.net/KCMS/detail/detail.aspx?filename=xmjs200306005&dbname=CJFD&dbcode=CJFQCHEN Qing-ru, LUO Zhen-fu. Review on dry coal separation[J]. Coal Preparation Technol, 2003, (6):34-40. http://kns.cnki.net/KCMS/detail/detail.aspx?filename=xmjs200306005&dbname=CJFD&dbcode=CJFQ [6] 徐荣声. 煤中矿物质在热转化过程中的演化行为[D]. 北京: 中国矿业大学, 2016. 煤中矿物质在热转化过程中的演化行为XU Rong-sheng. Behaviors of minerals in coal during the processes of thermal transformation[D]. Beijing:China University of Mining and Technology, 2016. 煤中矿物质在热转化过程中的演化行为 [7] 张景, 陈洪博, 张宇宏.添加助熔剂降低晋城煤高灰熔融性温度研究[J].煤质技术, 2015, (1):49-52. doi: 10.3969/j.issn.1007-7677.2015.01.015ZHANG Jing, CHEN Hong-bo, ZHANG Yu-hong. Research on reducing ash fusibility temperature of Jincheng coal by utilizing limestone[J]. Coal Quality Technol, 2015, (1):49-52. doi: 10.3969/j.issn.1007-7677.2015.01.015 [8] 刘锦启, 陈前林, 王景行.添加剂对无烟煤灰熔点和成浆性能的影响[J].煤炭学报, 2013, 38(2):483-488. http://www.oalib.com/paper/4232259LIU Jin-qi, CHEN Qian-lin, WANG Jing-xing. Effect of additive on ash melting point and pulping performance of anthracite[J]. J China Coal Society, 2013, 38(2):483-488. http://www.oalib.com/paper/4232259 [9] SONG W J, TANG L H, ZHU X D, WUA Y Q, RONG Y Q, ZHU Z B, KOYAMA S. Fusibility and flow properties of coal ash and slag[J]. Fuel, 2009, (88):297-304. http://www.sciencedirect.com/science/article/pii/S0016236108003499 [10] KONG L X, BAI J, LI W, WEN X D, LI X M, BAI Z Q, GUO Z X, LI H Z. The internal and external factor on coal ash slag viscosity at high temperatures, Part 3:Effect of CaO on the pattern of viscosity-temperature curves of slag[J]. Fuel, 2016, (179):10-16. http://www.sciencedirect.com/science/article/pii/S0016236116301004 [11] JAK E. Prediction of coal ash fusion temperature with the FACT thermodynam ic computer package[J]. Fuel, 2002, (81):1655-1668. https://www.sciencedirect.com/science/article/pii/S0016236112004668 [12] CHAKRAVARTY S, MOHANTY A, BANERJEE A, TRIPATHY R, MANDAL G K, BASARIYA M R, SHARMA M. Composition, mineral matter characteristics and ash fusion behavior of some Indian coals[J]. Fuel, 2015, (15):96-101. http://www.sciencedirect.com/science/article/pii/S0016236115001568 [13] 白进, 孔令学, 李怀柱, 郭振兴, 白宗庆, 尉迟唯, 李文.山西典型无烟煤灰流动性的调控[J].燃料化学学报, 2013, 41(7):805-813. http://manu60.magtech.com.cn/rlhxxb/CN/abstract/abstract18214.shtmlBAI Jin, KONG Ling-xue, LI Huai-zhu, GUO Zhen-xing, BAI Zong-qing, YUCHI Wei, LI Wen. Adjustment in high temperature flow property of ash from Shanxi typical anthracite[J]. J Fuel Chem Technol, 2013, 41(7):805-813. http://manu60.magtech.com.cn/rlhxxb/CN/abstract/abstract18214.shtml [14] 孔令学, 白进, 李文, 白宗庆, 郭振兴.氧化钙含量对灰渣流体性质影响的研究[J].燃料化学学报, 2011, 39(6):407-412. http://manu60.magtech.com.cn/rlhxxb/CN/abstract/abstract17750.shtmlKONG Ling-xue, BAI Jin, LI Wen, BAI Zong-qing, GUO Zhen-xing. Effect of lime addition on slag fluidity of coal ash[J]. J Fuel Chem Technol, 2011, 39(6):407-412. http://manu60.magtech.com.cn/rlhxxb/CN/abstract/abstract17750.shtml