Table of Contents
1 Cover
5 Preface
6 Foreword
8 1 Purpose of Agitator Design References
9 2 Major Steps in Successful Agitator Design Define Process Results Define Process Conditions Choose Tank Geometry Calculate Equivalent Power/Airflow Combinations for Equal Mass Transfer Rate Choose Minimum Combined Power Choose Shaft Speed; Size Impeller System to Draw Required Gassed Power Decision Point: D/T and Gassing Factors OK? Mechanical Design Decision Point: Is the Mechanical Design Feasible? Repeat to Find Lowest Cost Repeat for Different Aspect Ratios Repeat for Different Process Conditions Finish Summary of Chapter References
10 3 Agitator Fundamentals Agitated Tank Terminology Prime Mover Reducer Shaft Seal Wetted Parts Tank Dimensions How Agitation Parameters Are Calculated Reynolds Number Power Number Pumping Number Dimensionless Blend Time Aeration Number Gassing Factor Nusselt Number Froude Number Prandtl Number Geometric Ratios Baffle Number Dimensionless Hydraulic Force Thrust Number Typical Dimensionless Number Curves A Primer on Rheology Newtonian Model Pseudoplastic or Shear Thinning, Model (Aka Power Law Fluid) Bingham Plastic Herschel–Bulkley Impeller Apparent Viscosity A Bit of Impeller Physics Summary of Chapter References
11 4 Agitator Behavior under Gassed Conditions Flooding kla Method Power Draw Method Visual Flow Pattern Method Effect on Power Draw Holdup Example of Holdup Calculation Holdup “War Story” Variable Gas Flow Operation Mechanical Effects Summary of Chapter References
12
5 Impeller Types Used in Fermenters
Impeller Flow Patterns
Examples of Axial Flow Impellers
Examples of Radial Flow Impellers
Examples of Mixed Flow Impellers
Examples