Numerical study on waste polyethylene pyrolysis driven by self-sustaining smoldering  

作　　者：PAN RuMing WU YiBo GUENE LOUGOU Bachirou SHUAI Yong DEBENEST Gérald 

机构地区：[1]School of Energy Science and Engineering,Harbin Institute of Technology,Harbin 150001,China [2]Institut de Mecanique des Fluides de Toulouse(IMFT)-Universite de Toulouse,CNRS-INPT-UPS,Toulouse 31400,France

出　　处：《Science China(Technological Sciences)》2024年第2期627-638,共12页中国科学（技术科学英文版）

基　　金：supported by the China National Key Research and Development Plan Project(Grant No.2018YFA0702300);the National Natural Science Foundation of China(Grant Nos.51950410590 and52227813)。

摘　　要：Polyethylene is the type of waste plastic that accounts for the most significant proportion of municipal solid waste.Waste polyethylene can be valorized via pyrolysis and produce value-added oil,gas,and char.On the other hand,self-sustaining smoldering is an emerging technical means to deal with sand/soil contaminated by organic matter.The high-temperature heat generated by smoldering can be used as a heat source for pyrolyzing waste polyethylene.Therefore,this study investigates numerically the pyrolysis of waste polyethylene driven by self-sustaining smoldering.A novel 4-step lumped kinetic model is proposed for simulating the pyrolysis of waste polyethylene.The results indicate that the operating parameters can determine the pyrolysis product yields by regulating the pyrolysis temperature and the volatile residence time.Note that higher temperatures and longer residence times favor the generation of shorter-chain pyrolysis products because of the intensified volatiles’secondary cracking.It can be concluded that a high interface-wall heat transfer coefficient(400 W m^(-2)K^(-1)),a low PE content(0.20),a high char concentration(2.4%),and a moderate air velocity(0.040 m s^(-1))are beneficial to oil yield.To some extent,this study may broaden the boundaries for the application of self-sustained smoldering-driven pyrolysis.

关 键 词：self-sustained smoldering waste polyethylene thermal decomposition oil production waste valorization 

分 类 号：X705[环境科学与工程—环境工程] TQ325.12[化学工程—合成树脂塑料工业]