Perforated plate efficiency-effect of design and operating variables



Experimental plate efficiency and pressure drop data were obtained on the n-octane-toluene system in a 5 plate, 6 in. diam. column at atmospheric pressure. Hole sizes of 1/16, 1/8, and 3/16 in.; 5.68 and 12.5% free areas; weir heights of 1, 2, and 3 in.; and plate spacings of 6, 12, 18, and 24 in. were studied. Reflux ratios of one, two, four, five, ten, and total were utilized to determine the effect on efficiency.

It was found that hole diameter, free area, plate spacing, and a wide range of reflux ratio had relatively small effect on efficiency and pressure drop; however weir height and lower reflux showed relatively larger effects on both variables.

Efficiencies and pressure drops were lower than those predicted from published correlations particularly at low flow rates.