葡萄树枝烟气气氛下热解气化特性研究

以葡萄树枝为研究对象，采用热重-傅里叶变换红外光谱（TG-FTIR）联用技术，研究了反应气氛和升温速率对其热解特性的影响。结果表明：在烟气气氛（80% N₂、15% CO₂、5% O₂）下，DTG曲线在80、350和800℃温度附近存在3个明显失重峰，而在氮气气氛下仅存在80和350℃左右2个失重峰；升温速率为30℃/min时，氮气气氛下样品失重率达80%左右，而烟气气氛下达到95%。说明烟气气氛可提高葡萄树枝转化率，促进热解气化反应的进行。升温速率对生物质热解气化过程有双重影响，提高升温速率有利于葡萄树枝挥发分析出，促进热解气化反应进行，但容易引起葡萄树枝炭结焦，进而影响热失重的进程。热解析出产物采用FTIR分析，结果表明：不同热解阶段气体析出产物及析出量差别很大，且不同热解产物的析出特性由葡萄树枝样品内部官能团的重组、断裂引起。360℃时热解析出的气相产物种类最多，主要包括CO、CO₂、H₂O和CH₄等小分子气体，以及醛类、烃类、羧酸类等大分子物质。

Grape Branches Pyrolysis and Gasification Characteristic in Flue Gas Atmosphere

Grape branches was used as the research object. The thermal degradation of grape branches was investigated at different heating rates in different atmosphere by using the thermo gravimetric-Fourier transform infrared spectroscopy(TG-FTIR). The results showed that there were some obvious weightlessness peaks in the DTG curves near 80, 350 and 800℃ in flue gas atmosphere(80% N₂, 15% CO₂, 5% O₂). When the heating rate was 30℃/min, the weight loss rates of the sample were about 80% in nitrogen atmosphere, and 95% in flue gas atmosphere. The transformation rate of grape branches could be raised and the amount of the gaseous products could be increased in flue gas atmosphere. The heating rate had a dual influence on the pyrolysis gasification process of grape branches. Improving the heating rate could increase the release of volatilization of grape branches and promote pyrolysis gasification reaction, but it would cause the charcoal coking, affecting the process of thermal weight loss. The pyrolysis products were analyzed by Fourier transform infrared spectroscopy, it showed that the gas phase products in different stages were various, and the precipitation characteristics of pyrolysis products were various, which were caused by restructuring and fracturing of internal functional groups of grape branches. The precipitated products of pyrolysis at 360℃ were the most, including small molecule gases such as CO, CO₂, H₂O, CH₄, and macromolecule substance such as aldehydes, hydrocarbons and carboxylic acids.