矿物质组分对低品质生物质热解过程的影响

Effect of minerals on the pyrolysis of low-quality biomass

通过酸洗脱除低品质生物质(鸡粪与猪粪)中的矿物质组分,并使用热重分析仪对酸洗前后样品的热解行为进行了研究.结果表明,由于两种农林废物的有机组成和矿物质含量不同,导致其热解行为差异较大.鸡粪中含有大量的CaCO3,其在高温下分解放出CO2,并与鸡粪半焦中的碳发生气化反应.酸洗不但改变了禽畜粪便中矿物质的含量,而且改变了该废物中的有机组成,导致酸洗后样品热解行为的改变.运用一级反应动力学模型求取了热解动力学参数,发现模型的拟合度较好,酸洗后鸡粪的热解活化能较原样降低,而猪粪则相反.

The low-quality biomass,including hen manure（HM） and pig manure（PM）,were pretreated by acid washing and the pyrolysis behavior of the biomass wastes before and after acid washing was investigated using TG analyzer.TG results indicate that the difference between the pyrolysis behaviors of HM and PM is mainly attributed to the difference in their organic components and mineral composition.XRD results show that HM contains a large amount of CaCO3.The gasification reaction between HM char and CO2,which is from the decomposition of CaCO3 contained in HM,occurs at high pyrolysis temperature.The pretreatment induces the changes not only in mineral composition but also in organic constituents.The kinetic parameters can be calculated using first-order reaction model with good correlation.The activation energy of de-mineralized HM during pyrolysisis lower than its origin sample,but that of the de-mineralized PM is higher than PM.