Modeling and flowsheet simulation of vibrated fluidized bed dryers / Sören Ernst Lehmann.

Format:

Book

Author/Creator:

Lehmann, Sören, 1990- author.

Series:

SPE-Schriftenreihe

SPE-Schriftenreihe ; 18

Language:

English

Subjects (All):

Fluidized-bed furnaces.

Cohesion.

Drying.

Physical Description:

1 online resource (183 pages)

Edition:

1st ed.

Place of Publication:

Göttingen : Cuvillier Verlag, [2021]

Summary:

Fluidized bed dryers are the prime choice when it comes to drying of heat sensitive products, commonly processed in the pharmaceutical and food industry. As many products in these industries are fine and cohesive, mechanical vibration of the dryer is used to enable or improve fluidization. Thus, the goal of this thesis is the development of a fluidized bed drying model that accounts for the influence of mechanical vibration of the dryer, as well as its implementation in an open-source flowsheet simulation framework. Continuously operated fluidized bed dryers under steady-state conditions are the focus of this thesis. The aim during model development and implementation is the broadest possible application range of the model. A custom-built vibrated fluidized bed dryer is designed and constructed for comprehensive investigations of fluidized bed hydrodynamics and drying kinetics. Based on experimental investigations, a semi-empirical model for hydrodynamics of fine and cohesive powders is developed. The new model is combined with established models to allow for the flowsheet simulation of fluidized bed dryers for particles of all Geldart groups. Additionally, the influence of vibration is accounted for. Comprehensive validation experiments are performed for particles of different Geldart groups, different dryer geometries and a variety of process parameters, including mechanical vibration. Comparison of model predictions with experimental data attributes high accuracy of predicted particle and gas properties. Furthermore, sensitivity analyses are conducted to identify potential weaknesses in underlying model assumptions. Hereby, the validity of underlying assumptions is confirmed and potential optimization parameters for different applications are identified. The proposed model is unprecedented in terms of range of process parameters, variety of particle properties and dryer geometries, tested and found valid for.

Contents:

Intro

Acknowledgment

Abstract

Contents

Symbols

1 Introduction

1.1 Fluidized Bed Technology

1.2 Flowsheet Simulation of Solids Processes

1.3 Objectives and Strategy

1.4 Outline of the Thesis

2 Modeling of Fluidized Beds

2.1 Modeling of Fluidized Bed Hydrodynamics

2.2 Modeling of Fluidized Bed Drying Processes

3 Experimental Methods

3.1 Powder Characteristics

3.2 Preparation of Experiments

3.3 Pilot-Plant-Scale Vibrated Fluidized Bed Dryer

3.4 Lab-Scale Fluidized Bed Dryer

4 Model Development

4.1 Hydrodynamics of Cohesive Powders under Vibration

4.2 Residence Time Distribution

4.3 Drying Kinetics

4.4 Model Implementation

5 Simulation Results

5.1 Validation

5.2 Sensitivity Analysis

5.3 Application

6 Conclusion

Appendix A

Appendix B

Appendix C

Appendix D

Bibliography.

Notes:

Description based on print version record.

Includes bibliographical references.

Other Format:

Print version: Lehmann, Sören Ernst Modeling and Flowsheet Simulation of Vibrated Fluidized Bed Dryers

ISBN:

9783736975392