摘要
采用实验研究和理论分析相结合的方法研究了体积分数为0.5%～3%的超低浓度甲烷在以0.5%Pd/Al_2O_3(质量分数)为催化剂颗粒的流化床中燃烧时的流动特性。考察了气固流动、催化燃烧对床层膨胀的影响规律,分析了气泡沿炉膛高度方向生长的特性,研究了气固流动对流化床内压力脉动的影响规律。研究表明:随着温度的升高,床层膨胀高度增加;流化风速增大,床层的空隙率增加,床层膨胀高度增加;温度对气泡的生长影响不明显;流化风速增加时,进入气泡相的气体量增加,气泡直径增大;流化床床层表面的压力波动幅度大于床层内;甲烷通入时,床层内部平均压力下降,压力波动幅度减小,但床层表面压力波动幅度增加。
Flow characteristic of ultra-low concentration methane with its volumetric fraction 0.5%-3% was studied experimentally and theoretically during combustion in a fluidized bed reactor. 0.5% Pd/A1203 （mass fraction） was employed as catalytic particle in the fluidized bed. Effects of gas-solid flow and catalytic combustion on bed expansion were investigated. Bubble growth characteristic along reactor height was analyzed. Effects of gas-solid flow on pressure fluctuation of ultra-low concentration methane conversion were studied. The results show that bed expansion is prompted by increasing bed temperature. Bed voidage increases with fluidized velocity and results in growth of bed height. Bubble growth was barely influenced by temperature. The volume of bubble phase increases when fluidized velocity is accelerated, resulting in growth of bubble size. The pressure fluctuation amplitude in bed surface is larger than that in bed. When methane introduced to the reactor, average pressure and pressure fluctuation amplitude in bed reduce, while pressure fluctuation amplitude increases above bed surface.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2013年第3期484-487,共4页
Journal of Engineering Thermophysics
基金
国家自然科学基金(No.51206200)
中央高校基本科研业务经费(No.CDJZR12140031)
关键词
超低浓度甲烷
流化床
催化燃烧
气泡生长
压力脉动
ultra-low concentration methane
fluidized bed
catalytic combustion
bubble growth
pressure fluctuation
