If an identical breakthrough curve $($as in Q$19)$ were obtained for a Packed Bed Reactor $($PBR$)$ filled with uniform fine sand of particle diameter $0\mathrm{.}2$ mm and the properties listed below, how many pore volumes would it take for a pulse injection of non$-$reactive tracer to exit the bed, assuming no dispersion?

Table $1.$ Plug Flow Reactor Parameters

Table $2.$ Packed Bed Reactor Parameters