摘要
利用同步热分析仪（TGA/DSC）,采用非等温法,开展了市政脱水污泥干化过程的动力学研究。分析了升温速率对污泥干燥过程的影响,确定出污泥干化过程的最概然机理函数G（α）MP,计算了不同升温速率下的表观活化能E和指前因子A。结果表明,污泥非等温干燥过程可以分为缓慢加速、快速加速和减速3个阶段;升温速率的增大会缩短加速段干化时间,但对减速段没有影响;随着升温速率的增加,干化活化能和指前因子先增大后减小,活化能在19.45-28.46 k J/mol之间变化,指前因子变化范围为1.5×105-5.0×106s-1,且在升温速率为15 K/min时两者达到最大值;干燥过程最概然机理函数的积分形式为G（α）MP=1-（1-α）4反应级数为4;污泥干燥过程的活化能和指前因子之间存在动力学补偿效应。
Thermogravimetric experiments of municipal dewater sewage sludge were carried out with nonisothermal temperature programs by TGA/DSC. The effects of heating rate on the drying of sludge were analyzed.The most probable mechanism function G（ α）MPwas obtained. The results indicated that three drying stages of the slowly speed-up,the fast speed-up and speed-down drying were distinguished in sludge drying. The time of the speed-up drying stage decreased with the raise of the heating rate,but no changes were found at speed-down drying stage. The active energy E and the pre-exponential A were calculated at different heating rates,they varied within the range between 19. 45 - 28. 46 k J/mol of E and 1. 5 × 105- 5. 0 × 106s-1of A. The maximum of E and A were obtained when the heating rate was 15 K/min. The most probable mechanism function G（ α）MP= 1-（1-α）4of drying progress was determined. According the results,the kinetic compensation effect between A and E existed.
出处
《环境工程学报》
CAS
CSCD
北大核心
2015年第9期4488-4494,共7页
Chinese Journal of Environmental Engineering
基金
国家水体污染控制与治理科技重大专项资助(2010ZX07319-002)
陕西科学技术研究发展计划项目资助(2013K13-02-05)
关键词
污泥
干燥动力学
双外推法
动力学补偿效应
sludge
drying kinetic
double extrapolation
kinetic compensation effect
