The feed to a cooling crystallizer is 2,000 kg/h of 30 wt% Na2S04 in water at 40°C. This solution is to be cooled to a temperature at which 50% of the solute will be crystallized as the decahydrate. Estimate the required heat-transfer area in m2 if an overall heat-transfer coefficient of 15 Btu/h-ft2 – oF can be achieved. Assume a constant specific heat for the aqueous solution of 0.80 cal/g-oC. Chilled cooling water will flow countercurrently to the crystallizing solution, entering the crystallizer at 10°C, and exiting at a temperature sufficient to give a log-mean driving force of at least 10°C.