炼化废液与褐煤混合物共热解特性及动力学分析

Co–pyrolysis characteristics and kinetics analysis of refining and chemicals waste water, lignite and their blends

中文关键词: 废水  褐煤  热解  动力学  Coats–Redfern法

英文关键词: waste water  lignite  pyrolysis  kinetics  Coats–Redfern method

中文摘要:

      利用热重分析法对炼化废液与褐煤混合物的共热解特性和组分间相互作用进行研究。在升温速率30°C.min_–1条件下,利用Coats–Redfern法求解不同掺混比例的废液固形物与褐煤混合物的热解动力学参数。废液固形物及其与褐煤混合物热解过程可分为三个阶段,而褐煤为两个阶段。随着废液固形物掺混比例的增加,混合物反应活性逐渐升高,TG曲线向低温区偏移且失重程度加剧,挥发分初析温度(T_i)、热解峰温度(T_p)、热解终止温度(T_f)及残留物含量(M_r)减小,最大失重速率(R_p)、平均失重速率(R_v)和挥发分综合释放特性指数(D)显著增大。废液固形物与褐煤在共热解过程中存在着一定的相互抑制作用。动力学分析结果表明,热解过程的各个阶段均可用级数反应模型来描述,活化能随温度升高而增大。

英文摘要:

      The co–pyrolysis characteristics of refining and chemicals waste water (RCW) and lignite, as well as the interactions between them, were investigated via thermogravimetric analysis (TGA). The pyrolysis kinetic parameters of RCW solid and lignite blends under different blending ratios were determined by the integral Coats–Redfern method at 30°C.min–1. The thermal decomposition process of RCW solid and various mixtures blended with lignite proceeded in three stages, while two stages for lignite sample. With the increase of RCW blending ratio, the reactivity of the blends enhanced, so the TG curves shifted to the lower temperature region and a more mass losses occurred. Therefore, the initial decomposition temperature (Ti), the peak temperature (Tp), the terminal decomposition temperature (Tf) and the residual mass (Mr) decreased, while the maximum mass loss rate of each peak (Rp), the average mass loss rate (Rv) and the comprehensive devolatilization parameter (D) dramatically went up. There existed some inhibitive interactions between RCW and lignite. The results of the kinetic analysis showed that each stage of the pyrolysis could be described by the order reaction model (Fn). The activation energy (E) increased with the reaction temperature.