Diseño y construcción de un secador experimental para sólidos con control de flujo y temperatura de aire.

Abstract

The present work summarizes the procedure to design an experimental rotary dryer, for use of the Industrial Process laboratory of the Faculty of Sciences. This is divided into processes of: structural, thermal design, drying processes and design of the control system. The structural design was limited to the design of the drum and the lifters or pallets. The design was done using Microsoft Excel and VBA Macros. Among the parameters calculated are: diameter of the dryer drum, speed of the drum rotation, length of the lifters, number of lifters, etc. The thermal and drying process design is based on the study of matter and energy balance. The objective was to determine parameters such as: drying air temperature, drying air flow, thermal power needed to perform the drying operation, water flow withdrawn from the solid, theoretical exit moisture of the material, etc. A microcontroller based on Arduino technology was used for the control system, as a data acquisition card and software / hardware interface. MATLAB was used for the construction of the data acquisition software. To study the behavior of the material in the drying process, three materials were selected: peas, wheat and corn. Through the drying method in the stove that allowed to obtain experimentally its drying parameters: critical humidity, equilibrium moisture and drying time. Finally, the operation of the equipment was evaluated through the validation with two materials: peas and corn, which obtained its drying speed curves. It can be concluded that the drying by rotary method in comparison with the method of drying by stove, is much faster, requiring only a quarter of the time.