生物质与含钒页岩共热解动力学研究

Co-pyrolysis kinetics analysis of biomass and vanadium bearing shale

针对含钒页岩热值低、热解难度大、热解过程中钒转换率低的问题,文章提出了生物质与含钒页岩共热解的方法,并研究了升温速率对生物质与含钒页岩共热解过程的影响,以及生物质对含钒页岩热解过程的作用机理。研究结果表明:生物质与含钒页岩热解所需的活化能均随着升温速率的加快而呈现出先减小后增大的变化趋势,含钒页岩热解的最佳升温速率为20℃/min,生物质热解的最佳升温速率为25℃/min;在生物质与含钒页岩共热解的过程中,含钒页岩会抑制生物质的热解,但生物质热解产生的大量碱金属等成分会对含钒页岩的热解产生一定的促进作用;玉米秸秆灰分中碱金属及金属氧化物的含量高于锯末灰,这使得玉米秸秆对含钒页岩热解的促进作用大于锯末。

The vanadium conversion rate of the vanadium bearing shale is low during pyrolysis due to its low calorific value. Based on that, a method for co-pyrolysis of biomass and vanadium bearing shale was proposed, the effect of heating rate on the co-pyrolysis process was studied, and the mechanism of biomass on the pyrolysis process of vanadium bearing shale was explored. The results show that a certain proportion of biomass contributes to the pyrolysis of vanadium bearing shale. The optimum pyrolysis heating rate of the biomass and vanadium bearing shale was 25 ℃/min and 20 ℃/min respectively. The alkaline and alkaline earth metal derived from biomass pyrolysis improved thermal decompose of the vanadium bearing shale, yet vanadium bearing shale inhibited biomass pyrolysis under co-pyrolysis conditions. The permotion of corn stalk on the vanadium bearing shale pyrolysis was better than sawdust for its higher alkaline and alkaline earth metal in the ash.