A two-bed carbon adsorption system is to be designed to handle 10,000 acfm of air containing 550 ppm of hexane. Laboratory studies indicate that carbon can adsorb 8 lbm hexane per 100 lbm carbon under the conditions at which the system will be operated. If the system operates at 90oF and 1.0 atm at a removal efficiency of 96%, determine the approximate dimension of each carbon bed. Bed regeneration and cooling will require one hour.