煤炭转化2024，Vol.47Issue(3)：13-26,14.DOI:10.19726/j.cnki.ebcc.202403002
基于ReaxFF MD模拟的生物质三组分共热解气相产物析出特性研究
Investigation on precipitation characteristics of gas products from three-component co-pyrolysis of biomass based on ReaxFF molecular dynamics simulation
摘要
Abstract
The effective utilization of biomass energy is an important way to achieve the"double carbon".In recent years,bio-pyrolysis technology has become one of the research hotspots,and a comprehensive understanding of the pyrolysis process and the precipitation char-acteristics of products at the molecular level is of significant importance.Based on the reaction molecular dynamics(ReaxFF MD)simulation,thermogravimetric(TG)analysis,and micro-pyrolysis experiments,the co-pyrolysis behavior of three components(cellulose,hemicellulose,and lignin)and the precipitation characteristics of gaseous products were studied.The results show that the thermogravimetric characteristics of the separate pyrolysis and co-pyrolysis of the three components,as simulated by ReaxFF MD,are consistent with the results observed in the TG experiment.Based on the first-order kinetic model,the actual activation energy of co-pyroly-sis is about 14.67%lower than the theoretical value of linear superposition,indicating that co-pyrolysis has a positive synergistic effect on the fracture of chemical bonds.In the three-compo-nent co-pyrolysis process,the main gases precipitated at low temperatures are water(H2O),car-bon dioxide(CO2),ethyl formate(C3H6O2),and furan(C4H4O),which come from the pyroly-sis of cellulose and hemicellulose,while at high temperatures,the main gases precipitated into methane(CH4),carbon monoxide(CO),and hydrogen(H2),which come from the pyrolysis of lignin.When cellulose and hemicellulose are pyrolyzed separately,the order of inorganic gas according to the yield from large to small is H2O,CO2,CO,H2.When lignin is pyrolyzed sepa-rately,the order is H2O,CO,CO2,H2.The order during the co-pyrolysis of three components is consistent with that during the separate pyrolysis of cellulose and hemicellulose.Cellulose and hemicellulose promote the pyrolysis of lignin and result in higher CH4 production,while the co-pyrolysis of three components promotes the decomposition of acetic acid(C2H4O2)and the for-mation of formaldehyde(CH2O).关键词
ReaxFF/生物质/共热解/协同效应/动力学Key words
ReaxFF/biomass/co-pyrolysis/synergistic effect/dynamics分类
能源科技引用本文复制引用
徐思佳,胡雨燕,胡维杰,张鹏飞..基于ReaxFF MD模拟的生物质三组分共热解气相产物析出特性研究[J].煤炭转化,2024,47(3):13-26,14.基金项目
上海市科技计划国际合作项目(22230730300). （22230730300）
