核桃壳热解分级冷凝产物分布特性研究

为研究热解温度、载气流量和冷凝温度对核桃壳热解产物分布的影响,在实验室研制的生物质热解与分级冷凝装置上对核桃壳热解进行实验研究,结果表明:液体产物收率随着热解温度的升高而增加,但增加速率逐步降低;载气流量对液体产物总收率及各级液体产物收率影响较小;冷凝温度对液体产物总收率影响较小,但对各级生物油的收率影响较大。GC/MS分析表明:热解温度为450~500℃时,酚类物质含量达到最大值;随着二级冷凝器温度的升高,二级生物油中酚类物质富集程度逐渐提高,酸类物质的富集程度逐渐降低,二级生物油的收率逐渐下降。

DISTRIBUTION CHARACTERISTICS OF PRODUCTS OBTAINED FROM FRACTIONAL CONDENSATION OF WALNUT SHELL PYROLYSIS

In order to investigate the effects of pyrolysis temperature,carrier gas flow rate and condensation temperature on the distribution characteristics of pyrolysis products of walnut shell,experimental study is conducted on the fixed-bed biomass pyrolysis reactor incorporated with multi-stage condensation columns. Results show that yield of liquid products continuously increases and finally levels off with the rising pyrolysis temperature. Carrier gas flow rate and fractional condensation temperature have minimal influence on the total yield of liquid products,while fractional condensation temperature has obvious effects on the yields of fractions. GC/MS analysis reveals that yield of phenolic products reach to the maximum with the pyrolysis temperature range from 450 ℃ to 500 ℃.Enrichment degree of phenolic products is improved,and enrichment degree of acid and yield of the second fraction are decreased with the increasing condensation temperature.