CAJ | 학술논문

以降烯烃催化剂作为大颗粒,FCC催化剂作为小颗粒,将冷的大颗粒加入至热的大、小颗粒双组分全混流化床中,考察流化床中颗粒间混合换热过程.结果表明,在全混流化状态下,流化床密相区内混合颗粒的平均粒径越小、床层气速越高和床温越高,冷、热颗粒间传热系数就越大.用颗粒的努塞尔数Nu_p和雷诺数Re_p关联试验数据时,必须考虑密相床层温度的影响.考虑换热的初始床温和冷颗粒温度后,关联式计算值与实验值的误差不超过30%,可用于双组分流化床颗粒传热系数的计算.
이강희경최화제작위대과립,FCC최화제작위소과립,장랭적대과립가입지열적대、소과립쌍조분전혼류화상중,고찰류화상중과립간혼합환열과정.결과표명,재전혼류화상태하,류화상밀상구내혼합과립적평균립경월소、상층기속월고화상온월고,랭、열과립간전열계수취월대.용과립적노새이수Nu_p화뢰낙수Re_p관련시험수거시,필수고필밀상상층온도적영향.고필환열적초시상온화랭과립온도후,관련식계산치여실험치적오차불초과30%,가용우쌍조분류화상과립전열계수적계산.
With an olefin-reducing catalyst as the large particle and FCC catalyst as the small particle, an experimental investigation on heat transfer characteristics of feeding cold large particles into the heated fluidized binary mixtures of small particles and large particles was conducted in a experimental hot fluidized bed.The particle-particle heat transfer coefficient was measured under operations of different fluidized gas velocities, bed temperatures and large particle mass ratio in bed mixture.The experiments showed that the heat transfer coefficient increased with the increase of fluidized bed temperature, superficial gas velocity and with the decrease of the average particle size of bed binary mixture when the binary mixtures was in full-mixed fluidized state.A new correlation between Nu_pand Re_p of the particles, involving the influences of the temperatures of initial bed mixture and cold feed particle, was put forward, which could predict the experimental data with the error less than 30%.