油页岩半焦与玉米秸秆混合燃烧特性研究

在空气气氛下利用TGA/DSC1型同步热分析仪进行了桦甸油页岩半焦与玉米秸秆的混烧实验。研究了升温速率和质量比对燃烧特性参数的影响;并与单一油页岩半焦的燃烧特性进行比较。结果表明:混合样品的挥发分初析温度和着火温度远低于油页岩半焦,但略高于玉米秸秆;随着升温速率的提高,混合样品挥发分初析温度和着火温度逐渐提高。升温速率一定时,随着玉米秸秆质量比增大,燃烧过程呈现向低温区迁移的趋势;并且低温段曲线峰值高,挥发分释放剧烈,改善了混合物燃烧特性。玉米秸秆质量比大于10%时,混合样品的各项燃烧特性指标也增大。采用相互影响指数RMS和MR值评价混烧过程的相互影响,研究表明相互影响作用主要发生在第二、第三和第四阶段,第二、第三阶段为有利影响,第四阶段为不利影响。当半焦与玉米秸秆质量比为7:3时,其相互影响最大且均为有利影响。应用KAS模型,分析了混合物燃烧动力学,结果表明,随着反应进行,活化能总体呈上升趋势,与TG-DTG曲线变化规律一致。研究结果可以为油页岩半焦与玉米秸秆的高效燃烧提供参考。

Experiment to Co-combustion Characteristics of Oil Shale Semi-Coke and Corn Straw

Co-combustion experiment of Huadian oil shale semi-coke and corn straw was conducted by TGA/DSC1 thermogravimetric analyzer in air atmosphere. The influence of heating rate and mass ratio on the characteristic parameters of the mixture is studied, and compared with the combustion characteristics of single oil shale semi-coke. The results showed that the volatile initial precipitation temperature and ignition temperature of mixed samples are much lower than oil shale semi-coke, but it slightly higher than corn straw. The volatile initial precipitation temperature and ignition temperature of the mixed sample are increased with the increase of heating rate. When the heating rate is constant, the combustion process presents the trend to the low temperature zone, the peak value of the low temperature section is high and intense release of volatile, thus improved combustion characteristics of the mixtures. When the mass ratio of corn stalk was greater than 10%, the combustion characteristics of the mixed sample are also increased. RMS and MR values are used to evaluate the mutual influence of the co-combustion process, the study showed that main effects of the interaction occurred in second, third and fourth stages, the second and third stages are the favorable effects, and the fourth stage is the adverse effect and when the mass ratio of the semi coke and the corn straw is 7:3, the mutual influence is the best. KAS model is applied to analyze co-combustion kinetics of the blends. The results show that activation energy presents a rising tendency during the impelling of reaction, which is unanimous to the change law of TG - DTG curves. The results can provide reference for efficient combustion of oil shale semi-coke and corn straw.