The space co-ordinate in the gel bead mass balance is discretized, making the partial
differential equation a set of ordinary differential equation (we took 31 grid points). To
mimic the plug flow of the dispersed phase, we took 15 tanks per medium tank. Per
medium tank 2×30+2+5=77 differential equations were solved simultaneously with a
solver for stiff differential equations.
Design of liquid-liquid-solid fluidised-bed bioreactors 385