【作者】 张一鸣；

【导师】 王淑勤；

【作者基本信息】 华北电力大学（河北） ， 环境工程， 2008， 硕士

【摘要】 本文首先对一小型流化床试验台的布风均匀性进行数值计算,并用实验手段检验计算结果,数值计算和实验结果一致,都表明了该小型流化床布风均匀;接着通过实验测试不同颗粒在实验台内的流动性能,通过比较选出进行热态实验时的最佳惰性载体。其次对纳米TiO₂促进氧化钙固硫进行了热重实验研究,结果表明:有氧气参与固硫反应时,温度高时,氧化钙的转化率高,而没有氧气的情况下则相反;氧气对氧化钙固硫起着阻碍的作用,纳米TiO₂削弱了这种阻碍作用;添加纳米TiO₂确实能促进氧化钙的转化率,650～750℃时有22%左右的促进效果。本文还利用未反应收缩核模型模拟氧化钙固硫的过程,发现该模型能很好的模拟该过程,表明CaO固硫反应前期为表面化学反应控制阶段,后期转为产物层扩散控制阶段,通过比较添加剂对两个控制阶段的影响,发现纳米TiO₂对产物扩散控制阶段影响较大。更多还原

【Abstract】 Numerical calculation was carried on a small-scale fluidized bed to reveal its fluidization behavior firstly which was tested by experimentation,and then four different kinds of grains were tested in this fluidized bed to find the best inert carrier for thermal test. And then the promotion effect to CaO desulfurization by nanometer TiO₂ were investigated by thermogravimetric analysis method and the results reveal that: the conversion of CaO is higher in higher temperature in the presence of oxygen, while lower in the absent of oxygen; oxygen act side effect in CaO desulfurization, which may be weakened by nanometer TiO2; Nanometer TiO2 have a promotion effect for CaO conversion which was about 22% in temperature 650～750℃. The kinetic behavior of desulfurization can be described by unreacted shrinking reaction core model which indicate that the overall rate of desulfurization is controlled initially by surface chemical reaction, and then controlled by layer diffusion, and nanometer TiO2 can prominent affect the second stage to promote CaO desulfurization.更多还原