AN EVALUATION OF MASS-TRANSFER COEFFICIENTS FOR NEW AND USED ION-EXCHANGE RESINS

Mass-transfer coefficients for cation and anion exchange were determin ed for new and used condensate-polishing resins in use currently at tw o power plants. Experiments were performed over a concentration range from 65 to 3240 ppb sodium and 100 to 5000 ppb chloride at superficial velocities from 0.015 to 0.033 m/s in both mono and mixed beds. Using a simple industry-standard experimental technique, overall mass-trans fer coefficients were obtained in the range from 1.2 x 10(-4) m/s to 2 .5 x 10(-4) m/s. Fouled resins had coefficients 30 to 40% less than ne w resins. The method used to calculate these mass-transfer coefficient s is compared with alternative data treatments that separate film and particle rate steps. Observations are compared with literature data.