Influence of Bed Geometry on the Drying of Skimmed Milk in a Spouted Bed

Maisa Tonon Bitti Perazzini,José Teixeira Freire,Fábio Bentes Freire

doi:10.4236/aces.2015.54046

Maisa Tonon Bitti Perazzini, José Teixeira Freire + Show 1 more

Open Access

https://doi.org/10.4236/aces.2015.54046

Copy DOI

Abstract

In this present work, the fluidynamic and drying process of skimmed milk in conical and conical-cylindrical spouted bed was analyzed as a function of different bed geometry and operating conditions. It used three internal cone angles (45°, 60° and 75°), different loads of inert particles (1.50, 3.00 and 4.50 kg) and a fixed static bed height (20.50 cm). Polyethylene particles of 4.38 mm of diameter and 930.50 ± 0.3 kg/m3 of specific mass were used as inert particles. An artificial neural network model was trained to predict the peak pressure drop and the minimum spout velocity from an experimental data bank. The experimental results showed a significant effect of geometric characteristics of the bed on fluidynamics parameters. It was also observed for the operating conditions that conical spouted bed and cone angle of 45° were more suitable for drying skimmed milk. The neural network provided predictions in good agreement with experimental data.

Highlights

Several studies have been conducted to investigate the operating conditions on the fluidynamics and drying of pastes in a spouted bed
Kmiec [11] reported that the minimum spouting velocity in a conical spouted bed is more dependent on the bed height than the minimum spouting velocity in conical-cylindrical spouted beds
From the results of this study, it was found that fluidynamic parameters and maximum capacity of water evaporation were influenced by both cone angles and load of inert particle in the range of operating conditions analysed

Summary

Introduction

Several studies have been conducted to investigate the operating conditions on the fluidynamics and drying of pastes in a spouted bed. Olazar et al [2] conducted a study using contactors with different geometries, solids of different characteristics and with wide range of air velocity. The authors observed that there were limits for cone angle, Do/Di and Do/dp. It was obtained the design parameters for the stable operation in a spouted bed. Olazar et al [3] investigated the effect of the operating conditions (base angle, air inlet diameter, stagnant bed height, particle diameter and air velocity) on the fountain geometry. It was seen that the contactor base angle had a major

Methods

Results

Conclusion