Abstract This study investigated the effects of torrefaction temperatures and dilute acid pretreatment on the quality of pyrolysis bio-oil and the distribution toward gaseous, liquid bio-oil, and char products from rice straw. Torrefaction of rice straw was conducted at different temperatures (225 °C, 250 °C, and 275 °C) for 30 minutes in a Py-GC/MS reactor. After the torrefaction process was completed, fast pyrolysis of torrefied rice straw was then performed at temperatures of 450 °C, 500 °C and 550 °C with a heating rate of 1000 °C/s and held for 20 seconds in the same micropyrolysis reactor. The results showed that the decrease of pyrolysis bio-oil, gas, and water, are observed when the torrefaction temperature increases. However, the decreasing trend of pyrolysis char yield was observed when the torrefaction severity increases at pyrolysis temperatures 450 °C and 500 °C, but an increasing trend was noticeable at pyrolysis temperature 550 °C. The phenolic components in pyrolysis bio-oil from torrefied rice straw were lower compare to raw rice straw. The torrefaction process helps improve the quality of pyrolysis bio-oil in terms of reducing some water, acid, and oxygenated species. The torrefaction temperature of 225 °C with the pyrolysis temperature of 550 °C is indicated as the optimum condition in our study. Additionally, the removal of mineral content from rice straw promoted higher yields of pyrolysis bio-oil, particularly levoglucosan. The acid pretreatment method also improved the pyrolysis product distribution in terms of enhancing bio-oil yield and reducing water, gas, and char.

中文翻译：

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烘焙温度和酸预处理对稻草快速热解生物油产量和品质的影响

摘要 本研究调查了烘焙温度和稀酸预处理对热解生物油质量的影响，以及稻草向气态、液态生物油和焦炭产物的分布。在 Py-GC/MS 反应器中，在不同温度（225 °C、250 °C 和 275 °C）下对稻草进行烘焙 30 分钟。烘焙过程完成后，然后在450°C、500°C和550°C的温度下以1000°C/s的加热速率对烘焙稻草进行快速热解并在同一微热解反应器中保持20秒. 结果表明，当烘焙温度升高时，观察到热解生物油、气和水的减少。然而，在热解温度 450 ℃和 500 ℃时，当烘焙程度增加时，观察到热解焦产率下降的趋势，但在热解温度 550 ℃时，增加趋势很明显。与生稻草相比，来自烘焙稻草的热解生物油中的酚类成分较低。在减少一些水、酸和含氧物质方面，烘焙过程有助于提高热解生物油的质量。在我们的研究中，225°C 的烘焙温度和 550°C 的热解温度被认为是最佳条件。此外，从稻草中去除矿物质含量提高了热解生物油的产量，尤其是左旋葡聚糖。酸预处理方法在提高生物油产率和减少水分方面也改善了热解产物分布，