Question $4[20$ Marks$].$

A fluidized bed with a diameter of $0\mathrm{.}8m$ and height $3\mathrm{.}5m,$ is used to process $150\mathrm{.}5{10}^{3}c\frac{m^3}{s}$ of

gaseous reactant. per second. The disengaging length of the bed is $2m.$ The catalysts particles are

cylindrical in shape with an average diameter of $150.$

$($a$)$ Estimate the Reynolds number of flow of the fluid and hence the minimum fluidization

velocity in the bed. $[12$ marks$]$

$($b$)$ Estimate the weight of the catalysts in the bed. $[5$ marks$]$

$($c$)$By what percentage will your results in $($a$)$ change if the catalysts were spherical particles. $[3$

marks$]$

$({}_c=1,200\frac{kg}{m^3}$;${}_g=1\mathrm{.}03\frac{kg}{m^3}$;$1\mathrm{.}4{10}^{-4}$ poise ;$g=9\mathrm{.}81\frac{m}{s^2}$;$=0\mathrm{.}058)$