垃圾衍生燃料掺混污泥共热解特性及动力学分析

摘要

利用热重-红外联用分析仪(TG-FTIR)研究了垃圾衍生燃料(RDF)、污泥及混合热解的反应动力学和气体产物析出特性.研究结果表明,RDF与污泥混合热解过程存在协同作用.当污泥的掺混比例为50％时,整个热解过程表现为促进作用,且在500～1000℃温度段的促进效果最为明显.采用Coats-Redfem法对热解过程进行动力学分析发现,RDF与污泥混合热解反应在低温段(240～380℃)和高温段(670～740℃)符合2级反应规律,而在中温段(430～540℃)符合1级反应规律;相对于RDF单独热解,RDF掺混污泥共热解的活化能明显降低.FTIR分析发现,RDF掺混污泥共热解对CO2和CO的析出影响不大,对CH4的产生有明显促进作用.同时,共热解也导致HCl、NH3和HCN等污染物析出增加.本研究结果可为RDF和污泥共热解工艺的开发与设计提供数据支撑.%In this paper,the reaction kinetic and gas product characteristics of pyrolysis of refuse derived fuel (RDF),sludge and their mixture were studied by using thermogravimetric analysis-Fourier transform infrared spectrometer (TG-FTIR).The results showed that there was synergistic effect in the co-pyrolysis process of sludge and RDF.When the proportion of sludge is 50％,the whole pyrolysis process presented promotion effect,and the effect is the most obvious at the temperature range from 500℃ to 1000℃.The Coats-Redfern method was used to analyze the kinetic parameters of the pyrolysis process.The results indicated that the co-pyrolysis reaction of RDF and sludge in the low temperature stage (240-380℃) and high temperature stage (670-740℃) conforms to the second-order reaction law,while meets the first-order reaction law in the middle temperature stage (430-540℃).Compared with RDF pyrolysis,the activation energy of co-pyrolysis of RDF and sludge decreased obviously,which indicated that co-pyrolysis could promote the pyrolysis reaction process.FTIR analysis showed that the co-pyrolysis of RDF and sludge has little effect on the precipitation of CO2 and CO,but promotes the production of CH4.Meanwhile,the co-pyrolysis results in an increase in the precipitation ofHC1,NH3 and HCN as well.The results of this study could provide data support for the development and design of the co-pyrolysis process of RDF and sludge.