食用菌培养基废弃物热解特性及动力学研究

Behavior and kinetics of catalyst pyrolysis for edible fungi residue

利用热重分析仪研究了温度、升温速率、粒径、催化剂类型对食用菌培养基废弃物热解行为的影响,并采用一级反应对其热解动力学进行了计算分析。由研究结果可知:随着升温速率的提高,热解起始温度、质量损失最大处的温度以及最大质量损失速率处的温度均有所提高,升温速率在10,20,30℃/min时,最大质量损失速率处的温度分别为333.0,344.5,352.8℃,对应的最大质量损失率分别为62.24%,64.19%,65.82%;随着粒径的不断增大,热解最大质量损失速率处的温度不断提高;催化剂对废菌棒的热解影响很大,质量损失速率峰明显地向低温区移动,对于没有混催化剂的废菌棒的质量损失率为65.82%,混有质量分数10%K2CO3后质量损失率为45.48%,而且加入K2CO3催化剂后,发现肩状峰消失了,只留下一个更宽的移向低温区的大峰,添加质量分数10%K2CO3催化剂活化能相比10%Ca O降低的幅度更大,说明K2CO3催化剂相比Ca O催化剂更有利于食用菌培养基废弃物的热解反应。

A thermogravimetric analyzer was used to study the influence of temperature,heating rate,particle size,type of catalyst on pyrolysis behavior of the edible fungi residue. Pyrolysis kinetics was calculated and analysed by using the first-order reaction. The results show that with the increase of heating rate, the initial pyrolysis temperature,temperatures at mass loss and at the maximum mass loss rate increase,when heating rate is 10,20,30 ℃ / min,the temperature at the maximum rate of mass loss is 333. 0,344. 5,352. 8 ℃,corresponding to the maximum mass loss rate of 62. 24%,64. 19%,65. 82%,respectively; with the increasing of particle size,the temperature at maximum pyrolysis mass loss rate increases; the catalyst has great impact on the pyrolysis of waste bacteria stick,the peaks of mass loss rate apparently shift to lower temperature,and the mass loss rate of waste bacteria stick without catalyst is 65. 82%,after 10% K2CO3 mixed with mass loss rate of 45. 48%. The shoulder peak disappears after adding K2CO3 catalyst,leaving only a larger peak toward low temperature. The activation energy with 10% K2CO3 catalyst reduces more drastically compared to 10% Ca O,indicating that K2CO3 catalyst is more conductive to the pyrolysis reaction of edible fungi residue compared to Ca O catalyst.