| In a horizontal liquid-solid circulating fluidized bed heat exchanger,the distribution ofthe particle is not uniform,the particle begins to deposite in heat transfer tube after adistance by gravity,which seriously restrict the effects of horizontal liquid-solid circulatingfluidized bed heat exchanger on heat transfer enhancement.Research shows that Kenicsstatic mixer can improve the particle distribution obviously which in the horizontalliquid-solid two-phase fluidized bed heat exchanger. However,the effect of Kenics on heattransfer and preventing-cleaning fouling performance remains unclear. To solve thissituation, setting Kenics static mixer into the device of horizontal liquid-solid two-phasefluidized bed heat exchanger, experiment was performed using saturated calcium sulfatesolution as working medium to investigate the effect of velocity of medium, aspect ratio ofKenics static mixer, particle volume fraction on heat transfer film coefficient, and furtheranalyses the heat transfer performance and preventing and removing fouling effect ofliquid-solid horizontal circulating fluidized bed with Kenics. Meanwhile,the effects ofthese factors on pressure drop were observed.The research shows that Kenics static mixer can improved heat transfer performanceand preventing-cleaning fouling greatly. Under the same condition,heat transfer filmcoefficient increases with the aspect ratio increasing and increases with particle volumefraction increasing.The heat transfer film coefficient of installing the Kenics static mixerwith twist ratio Y=3.5in liquid-solid horizontal circulating fluidized bed can be increasedby a factor of0.22~0.59than without, under the condition of4%particles, the maximumheat transfer film coefficient is2.4kW·m-2·K-1.Besides, velocity of medium, aspect ratio ofKenics static mixer and article volume fraction are the main factor effected on pressuredrop.The pressure drop decreases with twist ratio increasing and increases with particlevolume fraction increasing.When the twist ratio of Kenics is3.5,particle volume fraction is4%, the comprehensive properties of heat transfer enhancement are the best.On the basisof these factors, empirical equation for heat transfer film coefficient and pressure dropwere established at steady state.It provides some theoretical information for the optimaldesign of the liquid-solid two-phase fluidized bed. |
