Thermal fragmentation and pulverization characteristic during pyrolysis of Huadian oil shale

doi:10.11949/j.issn.0438-1157.20170508

Abstract

Abstract:

A multi-particle characterization index describing the degree of fragmentation was proposed.Thermal fragmentation and pulverization properties of Huadian oil shale under different pyrolysis conditions were systematically investigated using the self-designed drum pyrolysis reactor,and the fragmentation mechanism was analyzed.The results showed that in thermo-mechanical force coupled loading mode,the rate of pulverization was 3.96 times of the sum of the individual loading modes,which indicated the synergistic effect of the coupled loading mode.The thermal force was the main influencing factor,its essence was the evolution of the internal pore structure,and the mechanical force was to enhance the phenomenon of fragmentation.The relative breakage rate and the pulverization rate were consistent with the change trend of pore structure.The smaller the feeding particle size,the smaller the overall degree of fragmentation.The higher the oil content,the greater the degree of fragmentation.The pulverization rate of the lean sample is lowest due to the higher content of calcite which was difficult to decompose into fine particles.Fragmentation and pulverization were two relatively independent concepts;there was no correlation between them.

Key words: pyrolysis, relative breakage rate, pulverization rate, particle size distribution, particle material, fragmentation mechanism

摘要：

提出了描述破碎粉化程度的多粒径表征指标，利用自行设计的转鼓式热解反应器系统地研究了桦甸油页岩在不同热解条件下的破碎粉化特性，并对破碎机理进行了分析。结果表明，热力-机械力耦合加载的方式下，粉化率是两种作用力单独加载方式之和的3.96倍，说明两者产生了协同作用，其中热力作用是煤颗粒发生破碎的主要影响因素，其实质是颗粒内部孔隙结构的演变，机械外力作为外在因素，其作用是增强宏观破碎现象；相对破碎率和粉化率与孔隙结构的变化趋势相一致；入料粒度越小，整体破碎程度越小；含油率越高，破碎程度越大，中矿油页岩因方解石含量较高在热解过程中不易分解为细小颗粒，因此粉化率最低；破碎和粉化是两个相对独立的概念，两者之间不存在相关性。

关键词: 热解, 相对破碎率, 粉化率, 粒度分布, 颗粒物料, 破碎机理

CLC Number:

TE662

SUN Nanxiang, WANG Yue, BAI Xiangfei. Thermal fragmentation and pulverization characteristic during pyrolysis of Huadian oil shale[J]. CIESC Journal, 2017, 68(10): 3959-3966.

孙南翔, 王越, 白向飞. 桦甸油页岩热解过程中的破碎粉化特性[J]. 化工学报, 2017, 68(10): 3959-3966.

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