生物质花生壳热分解及热分解模拟

Thermal Decomposition Kinetic and Simulation of Biomass Peanut Shell

用NETZSCH-STA409PC热分析仪研究了生物质花生壳的分解规律和动力学.花生壳的热分解主要有3个失重过程,第1个发生在80～100℃,为失水过程,对应DSC为吸热,失重量6%;第2个发生在100～380℃,为花生壳的热分解过程,该过程为吸热,失重量54%;第3个发生在380～700℃,为热分解残余有机物缓慢分解过程,失重量为16%;700℃后,基本恒重.讨论升温速率、粒度、气速对热分解曲线的影响.拟合了动力学方程函数,并求出动力学参数.花生壳分解可用三维扩散模型(D3)模拟,活化能E=141.67kJ.mol-1,指前因子lgA=8.645 4,用所得D3模型动力学方程预测,在花生壳分解过程中于360℃保温12min它的分解率近100%.这个结果能够用于优化气化分解过程.

This paper discusses thermal decomposition of biomass peanut shell with NETZSCH-STA409PC thermal analysis. Peanut shell thermal decomposition is composed of 3 TG loss, the first step TG loss is 6℃ dehydration and occurred at 80--100℃ ; the second step TG loss is 54 % and occurred at 320--380 ℃ ,this step is the mainly peanut shell thermal decom- position; the third step TC- loss is 16% and occurred at 380--700℃, it is the thermal decomposition of residual ; Effects of temperature rising rale, grain size and purge-gas flow rate on peanut shell decomposition character are studied. Kinetic function was obtained and kinetic parameters were calculated. The correlation coefficient is 0. 996 7. The results show that peanut shell decomposition is a 3-dim. diffusionJanders type reaction（D3）, The reaction activation energy E=41. 67 kJ · mol^- 1, lgA= 8. 645 4. The D3 kinetic function predicts that peanut shell decomposition is 100% at 360℃ for 12 minutes. This result can be used to optimize gasification process.