Effect of temperature on the drying rate of gin run cotton seed

Moisture control during the harvesting, storage, and processing phases of cotton production is essential for producing a quality product. Basic information relating environmental parameters to equilibrium moisture content and the moisture transfer rates for cotton and its component parts will lead to a better understanding of the processes involved and design and control criteria for cotton conditioning equipment. This report depicts the moisture desorption rates for gin run cotton seed. Absorption values are shown for temperatures of 20 and 35 degrees C and desorption values for temperatures ranging from 20 to 130 degrees C (68-266 degrees F). The desorption (drying) moisture data were plotted against time and found to be exponential in nature. Nonlinear regression analysis was used to fit the value of the coefficients in the theoretical falling rate equation to the experimental data. The desorption (drying) data fit the theoretical falling rate (exponential decay)function reasonably well, especially at temperatures above 100 degrees C. Temperature significantly affected the coefficient containing the diffusivity parameter in the nonlinear equations. A generalized solution of the falling rate equation was developed as a function of absolute temperature, which should be suitable for engineering calculations. Results indicate that moisture absorption by cotton seed undergoes two absorption phases. The first absorption phase appears to be physical in nature and approximates the curves of other biological materials. The second phase, which shows an increased moisture absorption rate after a leveling off period, may indicate increased metabolic activity