Patent ID: 8173835

Claim:
A method for drying solid particles comprising an aromatic dicarboxylic acid and a liquid, comprising: (a) introducing a wet cake comprising the solid aromatic dicarboxylic acid particles and at least one liquid into a thin layer contact dryer comprising a heated inner surface and a paddle rotor which imparts centrifugal and axially forward force to the wet cake; (b) forming a layer of wet cake of at least 10% of the solid particles having an average thickness of less than 1.5 inches over at least a portion of the heated inner surface and (c) removing the liquid from the solid particles of the aromatic dicarboxylic acid to thereby produce substantially dry aromatic dicarboxylic acid particles, wherein the at least one liquid comprises at least one of water and acetic acid, the wet cake comprises from about 2 to about 25 weight percent liquid, a feed rate of the wet cake to the thin layer contact dryer is at least about 20 lbs/hour per square foot of heated surface area of the thin layer contact dryer, an average residence time of the solid particles in the thin layer contact dryer is less than about 7 minutes, a temperature of the particles in the thin layer contact dryer does not exceed a temperature of sublimation or thermal degradation according to thermogravimetric analysis of the aromatic dicarboxylic acid, an exit temperature of the solid particles from the thin layer contact dryer is less than about 250° C. and the dry solid aromatic dicarboxylic acid particles comprise less than about 1 weight percent of the liquid.