Hydrodynamics of an inverse liquid-solid circulating conventional fluidized bed

An inverse liquid-solid circulating conventional fluidized bed (I-CCFB) is realized by injecting particles from the top of a conventional liquid-solid fluidized bed (0.076 m ID and 5.4 m height) that is operated in a newly developed circulating conventional fluidization regime located between the conventional and circulating fluidization regimes. The I-CCFB can achieve a higher solids holdup compared to both conventional and circulating liquid-solid fluidized beds. A new parameter, the bed intensification factor, is defined to quantify the increased solids holdup observed with external solids circulation. The Richardson-Zaki equation is shown to be applicable to the I-CCFB regime and can be used to correlate the slip velocity and solids holdup, both of which increase with the solids circulation rate. A new flow regime map is presented, including the I-CCFB and a variety of other liquid-solid fluidized beds.

Automated summary

An inverse liquid-solid circulating conventional fluidized bed (I-CCFB) is realized by injecting particles from the top of a conventional liquid-solid fluidized bed, which is operated in a newly developed circulating conventional fluidization regime. The I-CCFB can achieve a higher solids holdup compared to both conventional and circulating liquid-solid fluidized beds. A new flow regime map is presented, including the I-CCFB and a variety of other liquid-solid fluidized beds.