松木屑与废橡胶化学链共气化特性试验

High hydrogen syngas production from chemical looping co-gasification of sawdust and waste tires

在自行设计的两级固定床反应器上,对以天然贫铁矿石为载氧体的松木屑与废橡胶化学链共气化特性进行了研究。考察了载氧体的存在、废橡胶掺混比例、一级反应器温度、水蒸气流量等因素对生物质化学链共气化过程的影响。结果表明:载氧体的存在能显著改善气化效果;掺混一定量的废橡胶可以显著提高低位热值和碳转化率,并且呈现协同效应。本试验中最佳的废橡胶掺混比例为20%;共气化过程中的产气率、碳转化率均随温度的增加(750~950℃)而逐渐升高,但热值随温度的升高而有所下降;水蒸气流量的增加能显著提高合成气中H2的含量,进水流量保持在0.66g/min时,能实现生物质共气化过程产气率、碳转化率、低位热值等各项指标的最佳平衡。通过扫描电镜(SEM)、X射线衍射(XRD)等表征分析,发现天然贫铁矿石在长时间运行中表现良好的反应性和耐磨损性。

The chemical looping co-gasification process of sawdust and waste tires with natural lean iron ore as oxygen carrier was studied on a self-designed two-stage fixed-bed reactor. The effects of the presence of oxygen carrier, blending ratio of waste tires, the temperature of first-stage reactor and water flow rate on the chemical looping co-gasification process of biomass were investigated. The results showed that the presence of oxygen carrier could significantly improve the gasification effect and increase the gas yield;blending a certain amount of waste tires could significantly improve low calorific value and carbon conversion efficiency, and exhibited synergistic effect, the best blending ratio of waste tires in this experiment was 20%;the gas yield and carbon conversion efficiency in the co-gasification process rose with the increase of temperature, and the synergistic effect was gradually enhanced, but the lower calorific value decreased with the increase of temperature;the rise of water flow rate could significantly increase the content of H2 in the synthesis gas, and when the water flow rate was maintained at 0.66 g/min, the optimum balance of the gas yield, carbon conversion efficiency and low calorific value and other indicators of the biomass co-gasification process could be realized. Characterization and analysis by scanning electron microscopy(SEM) and X-ray diffraction(XRD) showed that natural lean iron ore exhibited good reactivity and wear resistance during long-term operation.