共查询到19条相似文献,搜索用时 46 毫秒
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低阶烟煤制取型煤的成型机理研究 总被引:2,自引:2,他引:0
选用水玻璃、膨润土和赤泥三种无机黏结剂,分别以四种不同的掺入量和低阶烟煤粉煤混合制取型煤.对型煤样品进行抗压强度的测定表明,型煤抗压强度随黏结剂掺比增大而增大,其中以膨润土为黏结剂的型煤强度远高于以水玻璃和赤泥为黏结剂的型煤强度,进一步的型煤微观结构电镜分析也证实了以膨润土为黏结剂的型煤其黏结性能相对最好,电镜切片表明,膨润土以朵状凝胶体楔入煤粒孔隙中并在煤粒表面形成整体网状结构.由于低阶烟煤自身的性质,以其制取的型煤往往对成型压力比较敏感,实验表明型煤的冷强度随成型压力的增大先增大后减小,存在一个最优成型压力. 相似文献
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型煤黏结剂的研究进展 总被引:3,自引:0,他引:3
根据黏结剂的结合机理和化学性质分别介绍了型煤黏结剂的两种分类方法。阐述了几种主要黏结剂的研究现状,重点分析了有机黏结剂、无机黏结剂、有机-无机复合型黏结剂的研究和应用情况。有机黏结剂的黏结性能和耐水性均较好,但热稳定性差,且价格昂贵,在一定程度上限制了其进一步的发展和应用。无机黏结剂来源广泛,价格便宜,具有一定的热强度,有的还有固硫作用,在中国的化肥用型煤和民用型煤生产中占很大比例;无机黏结剂生产的型煤热稳定性好,但可燃性差,增加了型煤灰分,降低了型煤发热量,无法满足用户对热值的需求。有机-无机复合黏结剂结合了有机黏结剂和无机黏结剂的优点,使黏结剂的多效性得到充分发挥,制备的型煤具有较高的机械强度和热稳定性,成为近年来研究开发的 相似文献
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以改性稻壳为黏结剂制备的生物质型煤为研究对象,进行了NaOH质量分数、加热温度、加热时间和改性稻壳添加量对型煤抗压强度和跌落强度影响的单因素试验和正交试验。单因素试验表明:当NaOH质量分数为2%,加热温度为85℃,加热时间为2.0 h,改性稻壳添加量为15%时,型煤机械强度较好。正交试验表明:改性稻壳添加量是影响型煤抗压强度和跌落强度的主要因素,其次为NaOH质量分数、加热温度、加热时间;当NaOH质量分数为3%,加热温度为90℃,加热时间为2.0 h,改性稻壳添加量为15%时,生物质型煤机械强度最好,其抗压强度为1426.5 N/个,跌落强度为97.8%。 相似文献
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镁基型煤黏结剂的防水固硫性能研究 总被引:1,自引:0,他引:1
为了提高型煤产品质量,对以氧化镁和氯化镁为基料制成的镁基型煤黏结剂进行了型煤机械强度和防水固硫等性能指标的考察,结果表明:氧化镁添加量为7%时,型煤在保证热值要求的同时,具有较高的机械强度和防水性能,具体为跌落强度98.3%,抗压强度843N/个,浸水强度310N/个,并且能够将22.6%的硫转化为硫酸盐固定在炉渣中;为了进一步提高镁基型煤的固硫效果,在以上黏结剂的基础上,添加煤矸石、粉煤灰等废弃物,当添加量分别为2.5%和2%时,型煤固硫率分别为44.0%和40.1%,有效减少了型煤燃烧过程中SO2的排放。 相似文献
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以神木红柳林煤矿筛选的0.2 mm粉煤为原料,马铃薯渣为粉煤成型黏结剂的主要组成,在冷压成型的条件下制得型煤。探究了黏结剂黏度、马铃薯渣粒度、型煤干燥时间及糊化剂对型煤抗压强度的影响,并采用FT-IR、SEM对粉煤及型煤进行了分析,结果发现:当黏结剂黏度为28565 mPa·s、马铃薯渣粒度为0.15 mm、型煤干燥时间为72 h及加入NaOH糊化剂时,型煤的抗压强度为3339.6 N/个;采用马铃薯渣基黏结剂制备的型煤的性能较为稳定,其表面起伏程度较粉煤明显降低,结构较为平整,使其具有较大的抗压强度。 相似文献
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年轻煤是煤液化的良好原料 ,但它的氧含量高增加了煤液化过程中无用的氢耗 ,对这些煤进行脱氧改质有重要的意义 .选择了四种年轻煤——霍林河、小龙潭、义马和神华煤在高压釜内水蒸气气氛下进行了脱氧改质的研究 .结果表明 ,处理后煤样的氧含量和含氧官能团降低显著 ,氧的脱除率最高达到了 2 0 .7% .此外 ,煤质还有一些其他的变化 ,如热值和碳含量有所提高 ,最高内在水分和挥发分降低 ,表明煤阶有所提高 .对煤中的总酸性基、羧基和酚羟基的化学分析显示 ,脱氧改质后煤样的羧基、酚羟基等含氧官能团明显降低 ,羧基和酚羟基的最高脱除率分别达到了78.5 %和 31 .3% ,达到了脱氧改质的目的 . 相似文献
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在内辊式高压型煤机上将一种印度尼西亚褐煤压制成高强度的无黏结剂型煤,对其比表面积、孔容积和表面官能团进行分析,测定了型煤的相对着火温度和绝热氧化升温速率,研究了其热解和燃烧行为特性.结果表明,印尼褐煤在干燥和高压成型过程中,发生了孔的收缩和崩塌,特别是微孔收缩程度要更大一些;干燥和成型过程中有羟基、羰基和羧基含氧官能团的分解;经过提质处理后,褐煤的自燃着火倾向降低,热解和燃烧反应性降低. 相似文献
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The low temperature oxidation of a Montana subbituminous coal was investigated using round bottom 100 ml flasks in constant temperature baths. The experiments were carried out in normal and oxygen enriched air at 30°C, 45°C and 70°C with particle sizes ranging from 4 mesh to 100 mesh. Periodic analysis of gas samples from the flasks provided the rate data. The reactivity of the as received coal was compared with that of the same coal dried (i) in high pressure steam and (ii) in hot water A rate equation has been proposed incorporating the effects of oxygen diffusion and surface reaction. For higher oxygen concentration and smaller particle sizes, the zero order surface reaction was found to be controlling. The temperature dependency of the reaction rate was found to be well represented by the Arrhenius equation. The activation energy varied slightly under various conditions between 15 to 20 kca)/g mole The reactivity of the hot water dried coal was found to be similar to that of the as received coal. Steam dried coal however, was found to be much less reactive. 相似文献
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The low temperature oxidation of a Montana subbituminous coal was investigated using round bottom 100 ml flasks in constant temperature baths. The experiments were carried out in normal and oxygen enriched air at 30°C, 45°C and 70°C with particle sizes ranging from 4 mesh to 100 mesh. Periodic analysis of gas samples from the flasks provided the rate data. The reactivity of the as received coal was compared with that of the same coal dried (i) in high pressure steam and (ii) in hot water
A rate equation has been proposed incorporating the effects of oxygen diffusion and surface reaction. For higher oxygen concentration and smaller particle sizes, the zero order surface reaction was found to be controlling. The temperature dependency of the reaction rate was found to be well represented by the Arrhenius equation. The activation energy varied slightly under various conditions between 15 to 20 kca)/g mole
The reactivity of the hot water dried coal was found to be similar to that of the as received coal. Steam dried coal however, was found to be much less reactive. 相似文献
A rate equation has been proposed incorporating the effects of oxygen diffusion and surface reaction. For higher oxygen concentration and smaller particle sizes, the zero order surface reaction was found to be controlling. The temperature dependency of the reaction rate was found to be well represented by the Arrhenius equation. The activation energy varied slightly under various conditions between 15 to 20 kca)/g mole
The reactivity of the hot water dried coal was found to be similar to that of the as received coal. Steam dried coal however, was found to be much less reactive. 相似文献
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用自制凝胶一沥青作复合粘结剂制备了炭素材料。通过测定不同配方、焙烧温度下试样的物理性能,认为9~#配方试样具有较好的导电性能和较高的抗压强度,沥青用量只有20%,明显低于传统炭素材料沥青用量。结果表明,凝胶一沥青复合粘结剂与石油焦粘结性能好,改变了传统的热压成型工艺。 相似文献