煤直接液化残渣与褐煤共热解动力学研究

Study on co-pyrolysis kinetics of coal direct liquefaction residue and lignite

为了解决煤炭液化残渣在热解过程中软化熔融并剧烈膨胀导致难以利用的问题,在温度范围为30~900℃,升温速率分别为10、20、30、40℃/min的情况下,借助热重分析仪对煤直接液化残渣与褐煤进行程序升温共热解试验,采用Doyle法分析共热解动力学,将动力学结果与共热解协同作用进行关联。结果表明:共热解过程可用3个串联的一级反应描述,温度区间分别为200~310、310~470、470~900℃,其中310~470℃对应共热解反应的活泼分解阶段,反应活化能(40~50 k J/mol)远大于低、高温反应活化能(10~20 k J/mol)。液化残渣与褐煤共热解降低了活泼分解阶段的反应活化能,加快了反应速率,增大了热解失重率,使共热解反应在300~550℃表现出正协同作用。

In order to solve a softening and melting of the coal liquefaction residues and serious swelling hard to be utilized during the py-rolysis process,when the temperature scope was ranging from 30 ~ 900 ℃ and a condition of temperature rising rate was 10,20,30 and40 ℃ / min individually,with a thermo gravimetric analyzer,a programmed temperature rising co-pyrolysis test was conducted with the coaldirect liquefaction residues and lignite. A Doyle method was applied to analyze the co-pyrolysis kinetics and an interaction was conductedon the kinetics results and the co-pyrolysis synergetic effect. The results showed that the co-pyrolysis could be described three series firstgrade reaction and the temperature interval was 200 ~ 310,310 ~ 470 and 470 ~ 900 ℃ individually. Among them,310 ~ 470 ℃ was activeresolution stage of the co-pyrolysis reaction and the reaction activation energy(40 ~ 50 k J/ mol) was far higher than the low and high tem-perature reaction activation energy(10 ~ 20 k J/ mol). The co-pyrolysis of the liquefaction residues and lignite would reduce the reactionactivation energy of the active solution stage,could speed up the reaction rate,could increase the pyrolysis weight loss rate and could makethe co-pyrolysis reaction with positive synergetic effect at temperature of 300 ~ 550 ℃.