生物质与聚丙烯共热解特性研究

Co-pyrolysis characteristics of biomass and polypropylene

为深入认识生物质与废塑料共热解过程中的相互作用,通过热重分析仪和固定床反应器研究了杨木单独热解特性以及聚丙烯添加量对杨木和聚丙烯共热解产物分布和产品组成的影响。结果表明:500℃为杨木单独热解时获得焦油产物的最佳温度,最高焦油产率为31.2%;在低温段(小于380℃),杨木和聚丙烯共热解的最大失重速率实验值略大于理论值,在高温段(大于430℃),共热解DTG曲线的峰值温度向高温区偏移;共热解对气体产物的生成起到了正协同作用,提高了气体产物的低位热值,对焦油的生成起到了负协同作用,但共热解使焦油中的酚类、酸类、酮类、呋喃类等含氧化合物的含量降低,烯烃类化合物的含量显著提高;此外,共热解使半焦的石墨化程度提高。

To further understand the interaction in co-pyrolysis of biomass and waste plastics,the pyrolysis characteristics of poplar wood(PW)and the effect of polypropylene(PP)addition on the product distribution and composition of PW and PP co-pyrolysis were studied by thermogravimetric analysis and fixed bed reactor.The results showed that 50o C is the optimal temperature for PW pyrolysis to obtain tar product,and the maximum tar yield is 31.2%.The experimental value of the maximum weight loss rate of co-pyrolysis is slightly greater than the theoretical value in the low temperature range,and the peak temperature of the DTG curve in the high temperature range shifts to higher temperature zone.Co-pyrolysis of PW and PP has a positive synergistic effect on the generation of gas products,increasing the low heating value of gas products.Co-pyrolysis has a negative synergistic effect on the generation of tar.However,the oxygen-containing compounds(phenols,acids,ketones and furans)in tar decrease,and olefin compounds increase significantly.In addition,the degree of graphitization of co-pyrolytic char becomes higher.