Answer to Question #233509 in Chemical Engineering for Lokika

Question

Explain Breakthrough curve in fixed bed adsorbers.

Answer 1

A breakthrough curve is a plot of the values of time period against adsorbate concentration in a mixture of fluids, mostly ari or liquit at times, with the adsorptive. at the beginning of the procedure, air and vapour goes through a bed of an adsorber, in this case carbon, and the vapour is adsorbed as the air passes out. this goes on as lonf as the carbon has the capacity to adsorb the water vapour from the mixture.

when saturation is reached, the carbon cannot adsorb any more vapour and the vapour concentration in the effluent gas keeps increasing until the amount going out of the bed is equl to that coming in. T he performance of carbon can be determined by employing the breakthrough curves.

For an ideal case, the curve is symmetrical and S-shaped. The curve is decribed in terms of the midpoint which is a function of the vapour content in the air, bed capacity and rate of flow through it, and steepness which represents the rate, in which a steeper curve indicates a slow rate.