Study On Thin-layer Drying And Vibrofluidized Bed Drying Of Pumpkin Seeds

The thin-layer drying characteristics of pumpkin seeds were determined at different airtemperatures (50 to 700C) and air velocities (2.07 to 3.57 mIs). Linear regression was used todetermine the parameter values in two thin-layer models. The applicability of drying datas to themodels was tested. The Page equation gave the best fit to experimental data. A comparisonbetween experimental and predicted data for the fresh pumpkin seed was done at 70~C and 2.82in/s.A vibr鵤ted fluidized dryer with spiral movement of materials (SVFB) , which was characterizedby its high drying rate, compact construction and suitability for viscid materials , was used toconduct vibrated fluidized bed drying experiments . Regression equations of the dryerperformance was derived with process variables such as vibrating parameters, air temperatures, airvelocities and material moisture contents. Their Effects on the performance of SVFB dryer wasinvestigated. Quantitative graphical analyses were carried out to show the interaction betweenvariables. Optimum combination of the parameters was obtained from a integrated objectivefunction based on the vaporization intensity as well as the specific heat consumption.The heat and mass transfer properties of pumpkin seeds in SVFB dryer was represented. Somematerial physical properties involved such as specific heat, surface area, unit mass etc. wasdetermined at different moisture content.