生物质半焦CO_2气化反应活性的实验研究

Experimental study of the reactivity of biomass char with CO_2 by thermal analysis techniques

采用热分析技术中进行了麦秆半焦的CO2气化反应性试验,考察了不同的热解及气化条件对生物质半焦气化特性的影响.结果表明:生物质裂解时升温速率、保温时间、温度以及半焦气化温度对半焦反应活性均有影响.当升温速率为15℃/min时,半焦的反应活性最好;随着生物质裂解温度的增大和保温时间的增加,所制备的半焦反应活性主要呈降低的趋势.随着气化温度的提高,气化反应活性增加.生物质半焦的结构有序性和碳微晶尺寸,以及炭的沉积化或乱层化是影响生物质半焦反应性的主要原因.

The reactivity of the wheat stalk char with CO2 was studied at different conditions by thermal analysis techniques. The effects of different pyrolysis and gasification conditions on the gasification properties of biomass char were also investigated. The results show that the reactivity of char is influenced by the heating rate, temperature, holding time of pyrolysis and the temperature of gasification. The optimum reactivity of wheat stalk char is at heating rate is 15 ℃/min. The reactivity of the biomass decreases with the increase of pyrolysis temperature and soaking time while the reactivity of resulting chars is increased with gasifying temperature increase. It has been drawn that the reactivity of biomass char due to the micro-crystallite size of carbon, carbon deposition and confusion.