城郊乡村生活垃圾衍生燃料热解特性研究

将城郊乡村生活垃圾加工成粒径6.0 mm左右的垃圾衍生燃料(RDF),采用热重(TG)分析和红外光谱等研究其热解特性.结果表明:(1)在RDF挥发分阶段和生物质挥发分阶段,助燃添加剂处于活泼分解阶段,加入了30％(质量分数)秸秆、玉米芯等生物质作助燃添加剂后的RDF(以下简写为混合RDF)分子碎片正发生内部氢重排,总体挥发分产物较多,并且有明显的二次裂解,失重提高到4.85 mg,失重率约提高12％.在RDF与生物质重叠的碳固定阶段,助燃添加剂失重率有一定提高,热重微分(DTG)峰值速率增加,为RDF碳固定阶段的进一步热解提供了良好的支持.(2)快加热产气速率均大于慢加热.(3)热解终温越高,越有利气体析出.(4)RDF的热解固体产率随着热解终温的升高而降低,在850℃时为31.9％;热解气体产率随着热解终温升高而迅速升高,在850℃时可达49.8％.(5)根据红外光谱图,城郊乡村生活垃圾加工成的RDF中所含的氯元素基本上以HCl形式释放.(6)一级动力学反应可以准确地描述物料热解过程.

Study on the pyrolysis characteristics of refuse derived fuel from village solid waste

The village solid waste was processing into the refuse derived fuel(RDF) granules of diameter 6.0 mm.The pyrolysis characteristics of RDF were studied with the help of thermal gravity analyzer and Fourier transform infrared spectroscopy(FTIR).In the devolatilization period of RDF and biomass,the combustion-supporting agent was in the rapid decomposition period;adding 30%(mass ratio) of straw in RDF,the obtained compound RDF presented better pyrolysis characteristics than original RDF,the velocity product was greatly increased because of the internal rearrangement of hydrogen in molecular fragments;there was a significant secondary cracking found in compound RDF,the weightless rised to 4.85 mg and the weightless rate increased by about 12%.In the overlapping carbon fixation stage of RDF and biomass,the weightless rate of combustion-supporting agent was increased to a certain degree,peak rate also increased,which provided good support for the further pyrolysis of RDF.The gas producing speed was faster under the rapid heating mode,and higher final pyrollysis temperature was benefit for the gas yield.The solid pyrolysis product of RDF was decreased with increasing the final pyrolysis temperature,the yield was decreased to 31.9% after pyrolysis at 850 ℃,while the gas pyrolysis product was different,the gas yield was increased to 49.8% after pyrolysis at 850 ℃.Meanwhile,the infrared spectroscopy showed that most of chloride in RDF was released in the form of hydrogen chloride;the pyrolysis process of RDF could be expressed by first-order reactions.