热烟气气氛下生物质在流化床反应器中快速热解制取生物油

Biomass fast pyrolysis for bio-oil production in a fluidized bed reactor under hot flue atmosphere

摘要:

在对操作流化速度进行冷态实验以及流化床温度稳定性进行测试的基础上，研制了新型流化床反应器，并使用玉米秸秆为原料，探究了热烟气气氛下快速热解制取生物油的最佳反应温度以及床料。在最佳热解条件下，对糠醛废弃物、木糖废弃物以及海藻进行了实验研究，得到了各产物产率，并对得到的生物油进行了物理特性分析。结果显示，在最佳操作流速下，当温度为500 ℃时使用白云石为床料可以获得最大生物油产率。4种原料中玉米秸秆的生物油产率最高，达到42.3 wt%。在最佳热解条件下获得了4种物料不同含量的重油和轻质油，其中重油的物理特性差别很小，重油的热值比轻质油的热值高很多。不可冷凝气的高位热值是6.5?8.5 MJ/m3，因此不可冷凝气体可以作为一种燃料气被加以利用。

Abstract:

Fast pyrolysis experiments of corn stalk were performed to investigate the optimal pyrolysis conditions of temperature and bed material for maximum bio-oil production under flue gas atmosphere. Under the optimized pyrolysis conditions, furfural residue, xylose residue and kelp seaweed were pyrolyzed to examine their yield distributions of products, and the physical characteristics of bio-oil were studied. The best flow rate of the flue gas at selected temperature is obtained, and the pyrolysis temperature at 500 °C and dolomite as bed material could give a maximum bio-oil yield. The highest bio-oil yield of 43.3% (W/W) was achieved from corn stalk under the optimal conditions. Two main fractions were recovered from the stratified bio-oils: light oils and heavy oils. The physical properties of heavy oils from all feedstocks varied little. The calorific values of heavy oils were much higher than that of light oils. The pyrolysis gas could be used as a gaseous fuel due to a relatively high calorific value of 6.5?8.5 MJ/m3.