Q$4).10$ marks. A microfiltration unit used concentrate a suspension of $0\mathrm{.}8m$ spherical

particles has a permeate flux of $150\frac{L}{m^2}.h$ at $30C$ and a pressure drop of $2\mathrm{.}1$atm. Under the

same conditions, the pure water flux was $280\frac{L}{m^2}h.$ How thick a layer of particles would be

needed to account for the gel layer resistance if $=0\mathrm{.}35?=0\mathrm{.}801{10}^{-3}k\frac{g}{m}.s.$