采用热重分析仪，进行了桦甸和汪清页岩油泥在不同升温速率（5℃/min，10℃/min，20℃/min，40℃/min）下热失重实验，并通过瓦斯气析出情况研究页岩油泥热解机理。结果表明，页岩油泥热解分为3个阶段：第一阶段（20～180℃）为水分和轻质组分析出；第二阶段（180～360℃）重质组分稳定析出，是动力学研究的重点；第三阶段（360～600℃）为半焦炭化及矿物质失重过程。研究发现，催化剂 K2CO3能有效降低油泥热解温度及其残渣率，而 Al2O3对油泥热解催化不明显甚至起抑制作用。在页岩油泥热解过程中，生成的有机大分子侧链发生 C—C 键断链，生成小分子的烷烃和不饱和烃，在低压高温条件下，其断链位置倾向于碳链端部，使得小分子烃含量较多。% An experiment of pyrolysis for oil shale sludge from Huadian and Wangqing at certain heating rates (5 ℃/min,10 ℃/min,20 ℃/min,40℃/min) was conducted using a thermogravimetric analyzer. And pyrolysis mechanism of oil shale sludge was investigated by analyzing through the gas separation characteristics. Results showed that three stages were involved in the process of oil shale sludge pyrolysis. First stage characterized moisture and lightweight components dissolution (20—180 ℃ ); in the second stage (180—360 ℃),was that heavy components volatilized steadily, which was research focus of the dynamics;in the third stage (360—600 ℃) semicoke carbonized and mineral substances reduced in weight. Researches showed that K2CO3 could effectively reduce the temperature of oil sludge’s pyrolysis and improve production rate of oil. However,Al2O3 not only had no obvious catalysis on the pyrolysis of oil shale sludge but also inhibited the process. The generated organic macromolecular degraded due to heat,resulting in the break of carbon-carbon bond of macromolecules’ side chain and the production of smaller molecules paraffin and unsaturated hydrocarbon. In the condition of low pressure and high temperature,the chain scission tended to happen at the end of carbon chain,causing the number of smaller molecule hydrocarbon to increase.
展开▼
