煤与牛骨混合燃烧过程及热动力学分析

Analysis of Coal-beef Bone Co-combustion and the Thermal Dynamics

骨类垃圾为厨余垃圾中的重要组成部分,为了缓解厨余垃圾的处理压力,选取无烟煤与烟煤分别按照不同比例与牛骨掺混,采用ZTC-B型综合(同步)热分析仪对其混合燃烧过程进行了热重分析,并对结果进行了动力学分析。结果表明:煤与牛骨单独燃烧的热重分析曲线差异明显;掺混燃烧时随着混合物中牛骨质量分数的增加,DTG峰值温度向着低温区偏移,整体燃烧温度区间变窄,综合燃烧特性指数不断降低,燃尽特性指数不断升高;掺混燃烧过程中会产生协同作用,无烟煤、烟煤与牛骨的混合物在400℃左右产生了抑制作用,其相对值分别为-8%与-4%,在524℃和627℃左右产生了促进作用,其相对值分别为7%和9%。动力学分析表明采用2个连续一级反应模型可以很好地描述其掺烧过程。

Bone waste is an important part of kitchen waste.In order to alleviate the processing pressure of kitchen waste,anthracite and bitumite were mixed with beef bone in a different proportion for co-combustion.The ZTC-B type comprehensive(synchronous)thermal analyzer was used to examine the co-combustion,and the thermal dynamics were analyzed in thermogravimetry.Results show that the thermogravimetric analysis curves of coal and beef bone burning were obviously different.When the mass fraction of beef bone in the mixture increased,the peak temperature of DTG(derivative thermogravimetry)moved toward the low temperature zone.The overall combustion temperature range was narrowed,the comprehensive combustion characteristic index decreased,and the burnout characteristic index increased.Synergistic effect occurred in the co-combustion process.The co-combustion of anthracite or bituminous coal with beef bone was inhibited at around 400℃for about-8%or-4%,the promoting effects were obtained at 524℃or 627℃for about 7%or 9%,respectively.The thermal dynamic analysis showed that the co-combustion process could be described by two successive first-order reaction models.