采用多元非线性回归法的生物柴油动力学分析  

Kinetic analysis of biodiesel based on multivariate nonlinear regression method

作　　者：周毅 甘云华[1,2] 杨泽亮 ZHOU Yi;GAN Yunhua;YANG Zeliang(School of Electric Power Engineering, South China University of Technology, Guangzhou 510640, China;Guangdong Provincial Key Laboratory of Efficient and Clean Energy Utilization, Guangzhou 510640, China)

机构地区：[1]华南理工大学电力学院,广东广州510640 [2]广东省能源高效清洁利用重点实验室,广东广州510640

出　　处：《哈尔滨工程大学学报》2020年第7期1036-1042,共7页Journal of Harbin Engineering University

基　　金：国家自然科学基金项目(51776077);广东省基础与应用基础研究基金项目(2020B1515020040);华南理工大学中央高校基本科研业务费资助项目(2018ZD05)。

摘　　要：针对目前生物柴油的燃烧和热解动力学分析不够完善,本文采用热重分析仪-傅里叶红外变换光谱仪联用对生物柴油分别进行氮气和空气气氛下不同升温速率的实验,并分析所得到的热重-热失重速率(TG-DTG)曲线与红外光谱图。利用Kissinger法和Starink法分别计算出生物柴油在不同气氛下的活化能与指前因子。以无模式函数法所求解的动力学参数作为初值,通过多元非线性回归法求出相符的机理函数,并进行F-检验以验证其回归良好。结果表明:生物柴油热解和燃烧热重-热失重速率的曲线变化规律一致,皆随升温速率的提高而向高温区移动,且最大失重速率点接近;热解和燃烧过程中气态产物基本一致,仅在燃烧过程中在2250~2000 cm^-1处检测到一氧化碳的特征峰;多元非线性回归法分析得出生物柴油热解过程为单步动力学反应,燃烧过程为两步连续动力学反应。实验分析和回归求出的机理函数,可用于生物柴油燃烧和热解过程的化学反应动力学特性预测。Aiming to close the gap due to the insufficient analysis on the current combustion and pyrolysis kinetics of biodiesel,this study carries out pyrolysis experiments of biodiesel in nitrogen and air under different heating rates,using a thermogravimetric analyzer coupled with a Fourier transform infrared spectrometer.The measured thermogravimetry and derivative thermogravimetry curves(TG-DTG)and infrared spectra are then discussed.The activation energy and pre-exponential factors of biodiesel under different atmospheres are calculated by using the Kissinger and Starink method,respectively.The multivariate nonlinear regression method is used to find the most corresponding reaction model,by using the kinetic parameters solved by the model-free method as initial values,which is validated by F-test.Experimental results show that the varying trends in the TG-DTG curves of biodiesel pyrolysis and combustion are nearly the same:the TG-DTG curve moves to the high-temperature zone with the increase in heating rate,and the maximum mass loss rate is close.The gaseous products during the combustion and pyrolysis are almost the same,but only the characteristic peak of carbon monoxide is detected at 2250~2000 cm^-1 during combustion.By analyzing the multivariate nonlinear regression method,the biodiesel pyrolysis process can be described as a single-step kinetic reaction,and the combustion process can be described as a two-step consecutive kinetic reaction.The mechanism function obtained through experimental analysis and regression can be used to predict the chemical reaction kinetics of biodiesel combustion and pyrolysis.

关 键 词：生物柴油 动力学 热解 热重分析 动力学模型 多元非线性回归 傅里叶红外光谱 升温速率 

分 类 号：TK16[动力工程及工程热物理—热能工程]