烟草废弃物流化床热解转化实验研究

Experimental Study of Tobacco Waste Pyrolysis in a Fluidized Bed Reactor

为了探索烟草废弃物的高值化利用途径,采用热重、热解-气质联用(Py-GC/MS)等仪器对其原料特性及基础热化学转化特性进行探讨。在10 kg/h处理量的流化床热解反应系统开展烟草废弃物的热解转化研究,并对热解得到的气体、固体和液体产物特性进行分析,结果表明:1)烟草废弃物的堆积密度较小,孔隙率较高,其热解失重区间主要为150~400℃,最大失重速率发生在180和315℃附近;2)通过Py-GC/MS分析发现烟草废弃物热解生物油组分主要包括烟碱、烯烃、酮类、醛类、酸类、醇类、芳香烃、酚类、吡啶和吡咯类等;3)通过流化床中试热解实验发现,随着温度从300℃增加到500℃,生物油产率在450℃时达到最大值32.58%,其中烟碱组分含量最高,其次是酸、酮、酚和含氮杂环化合物;热解气体的产率随热解温度的升高不断增大,其主要成分是CO_(2)和CO,热解炭产率随热解温度的升高逐渐下降。

In order to probe the high-value utilization of tobacco waste,the basic physicochemical properties of the feedstock as well as their thermal conversion characteristics were tested using TG,and Py-GC/MS,etc.Then,the pyrolysis experiment of tobacco waste was carried out in a fluidized bed reactor with a feeding rate of 10 kg/h.The results showed that tobacco waste had a very low bulk density and high porosity.The mass loss during tobacco pyrolysis was mainly occurred in the temperature range of 150-400℃,and the maximum rate of weight loss occurred near 180 and 315℃.The Py-GC/MS analysis of tobacco waste suggested that the bio-oil was mainly composed of nicotine,olefins,ketones,acids,aldehydes,alcohols,aromatics,phenols,pyridines and pyrroles.According to the pyrolysis experiment in the fluidized bed reactor,with the increase of pyrolysis temperature from 300 to 500℃,the yield of bio-oil reached its maximum of 32.58% at 450℃.The dominant compound in bio-oil was nicotine,followed by acids,ketones,phenols,and N-heterocyclic compounds.In addition,the gas yield increased gradually with the increasing temperature,which was mainly composed of CO_(2)and CO,while the yield of solid char residue decreased.