Solid—Gas Separation

Preface1. Introduction 1.1. Principles of Particle Separation and Classification of Equipment 1.2. General Characteristics of Equipment 1.2.1 Flowrate—Pressure-Drop Relationship 1.2.2 Efficiency 1.2.3 Economic Criteria 1.2.4 Suitability for Different Conditions 1.3. Dimensionless Groups for Modelling and Equipment Scale-Up 1.3.1 The Effects of Particle Inertia and External Field of Acceleration 1.3.2 The Effect of Diffusion2. Efficiency of Separation 2.1. Introduction 2.2. Basic Definitions and Mass Balance Equations 2.2.1 Total Efficiency 2.2.2 Grade Efficiency 2.3. Basic Relationships Between ΕT, G(x) and Particle Size Distributions of the Products and the Feed 2.4. Grade Efficiency Testing 2.4.1 Test Solids 2.4.2 Combination of the Material Streams 2.4.3 Evaluation of Results 2.4.4 Errors in the Measurement of Separation Efficiency 2.4.5 Factors Affecting Efficiency of Separation 2.5. Performance Predictions from Grade Efficiency Curves 2.5.1 Total Efficiency Determination 2.5.2 Determination of the Size Distribution of the Products 2.6. The Use of Separators in Series 2.6.1 Two Separators in Series 2.6.2 A Concentrator with a Separator in Series 2.6.3 A Concentrator with a Separator in Series, with Feedback3. Aero-Mechanical Dry Separators 3.1. Settling Chambers 3.1.1 Grade Efficiency Curves for Settling Chambers 3.1.2 Design of Settling Chambers 3.1.3 Application of Settling Chambers 3.2. Inertial Separators 3.3. Cyclones 3.3.1 Introduction 3.3.2 Dimensionless Groups and Operational Characteristics of Cyclones 3.3.3 Selection of Cyclones from Manufacturers' Data 3.3.4 Design of Cyclones for a Given Duty 3.3.5 Some Notes on Cyclone Construction, Properties and Applications 3.4. The Dual Vortex Separator 3.4.1 Principle of Operation 3.4.2 Design, Operational Characteristics and Properties of Dual Vortex Sepators 3.5. The Fan Collectors 3.5.1 Principle of Operation 3.5.2 Properties and Applications of Fan Collectors4. Aero-Mechanical Wet Separators (Scrubbers) 4.1. Introduction 4.2. Types of Scrubbers 4.2.1 Plate Scrubbers 4.2.2 Massive Packing Scrubbers 4.2.3 Fibre Bed Scrubbers 4.2.4 Pre-Formed Spray Scrubbers 4.2.5 Gas-Atomized Spray Scrubbers 4.2.6 Centrifugal Scrubbers 4.2.7 Baffle-Type Scrubbers 4.2.8 Impingement-and-Entrainment Scrubbers 4.2.9 Mechanically Aided Scrubbers 4.2.10 Moving Bed Scrubbers 4.2.11 Other Scrubber Designs 4.3. Comparison of Scrubber Performance5. Electrostatic Precipitators 5.1. The Physical Mechanisms Involved in Electrostatic Precipitation 5.1.1 Particle Charging, the Corona Discharge 5.1.2 Particle Migration Velocities 5.1.3 The Effect of Dust Resistivity 5.2. Types of Electrostatic Precipitators 5.2.1 Two-Stage Designs 5.2.2 Single-Stage Designs 5.3. Design of the Industrial Dry Plate Precipitators 5.3.1 The Discharge (Negative) Electrodes 5.3.2 The Collecting (Positive) Electrodes 5.3.3 Discharge Gap and Gas Velocity 5.3.4 Rapping and Vibration Mechanisms 5.3.5 Gas Distribution and Pressure Drop 5.3.6 Insulator Heating 5.3.7 Rectifiers 5.3.8 Sectionalization 5.3.9 Applications 5.4. Wet Electrostatic Precipitators 5.5. Performance and Operational Characteristics 5.5.1 Separation Efficiency6. Filters 6.1. Introduction 6.2. Mechanisms Taking Part in Gas Filtration 6.2.1 Inertial Separation 6.2.2 Direct Interception 6.2.3 Diffusion 6.2.4 Gravity and Electrostatic Separation 6.2.5 Screening and Blocking 6.2.6 Aerodynamic Forces and Piezophoresis 6.2.7 Particle—Fibre Adhesion Versus Bounce-Off and Dynamic Re-Entrainment 6.2.8 Combinations of Separation Mechanisms 6.2.9 Pressure Drop in Filter Media 6.3. Types of Gas Filters 6.3.1 Industrial Bag Filters 6.3.2 General Air-Conditioning Filters 6.3.3 High-Efficiency Filters 6.3.4 Deep Bed Filters 6.4. Filter Efficiency Testing7. Economics of Gas Cleaning; Equipment Selection 7.1. Cost—Efficiency Criteria for Comparisons of Performance 7.1.1 Literature Information on Gas-Cleaning Costs 7.1.2 A Cost—Efficiency Criterion Based on Running Costs 7.1.3 Electrical Energy Cost Equivalent Versus Cut Size 7.2. Selection of EquipmentReferences