Page 12 - Water Engineering Hydraulics, Distribution and Treatment

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Contents
Rates of Gas Absorption and
Water Renovation
11.16
Treatment Kinetics
400
Desorption
350
11.17
11.18
Monitoring Water Quality
13.5
Types of Aerators
402
11.19
Distribution to Customers
352
11.20
13.5.2
Glossary of Water Treatment
Spray Aerators
402
Systems
13.5.3
Air Diffusers
Problems/Questions
Mechanical Aerators
13.5.4
359
13.6
405
References
Factors Governing Gas Transfer
13.7
Design of Gravity Aerators
405
Design of Fixed-Spray Aerators
406
13.8
Chemicals Feeding, Mixing, and
Design of Movable-Spray Aerators
13.9
12
Design of Injection Aerators
13.10
407
Flocculation 363 352 360 348 351 13.4 13.5.1 Gravity Aerators 402 402 404 406
13.11 Mechanical Aerators 408
13.12 Oxidation for Removal of Dissolved
12.1 Introduction 363
Iron and Manganese 408
12.2 Handling, Storing, and Feeding
13.12.1 Solubility of Fe and Mn 408
Chemicals 363
13.12.2 Redox Reactions of Fe and
12.2.1 Points of Chemical
Mn 409
Addition 364
13.12.3 Precipitation of Fe and Mn 409
12.2.2 Chemical Metering
13.12.4 Kinetics of Oxygenation 409
Equipment 364
13.12.5 Engineering Management
12.3 Rapid Mixing 367
of Oxidative Removal of
12.3.1 Mechanical Mixers 369
Iron and Manganese 409
12.3.2 In-Line Static Mixers 370
13.13 Removal of Specific Gases 411
12.3.3 In-Line Mechanical
13.13.1 Methane 411
Blenders 371
13.13.2 Carbon Dioxide 411
12.3.4 Jet Injection Blending 371
13.13.3 Hydrogen Sulfide 411
12.3.5 Coagulant Diffusers 372
13.14 Removal of Odors and Tastes 414
12.3.6 Hydraulic Jumps 372
Problems/Questions 414
12.4 Rapid Mixing and Slow Flocculation 372
References 415
12.5 Flocculation 373
12.6 Mixing and Stirring Devices 373
12.6.1 Baffled Channels 373
12.6.2 Pneumatic Mixing and
14 Coagulation 417
Stirring 374
12.6.3 Mechanical Mixing and
Stirring 374 14.1 Introduction 417
12.7 Flocculator Performance 391 14.2 The Colloidal State 417
12.7.1 Mixing 391 14.2.1 Electrokinetic Properties of
12.7.2 Flocculator Inlet and Outlet Colloids 417
Structures 392 14.2.2 Hydration 418
12.7.3 Improving Basin Circulation 14.2.3 Tyndall Effect 418
with Baffles 392 14.2.4 Brownian Movement 418
12.8 Costs 393 14.2.5 Filterability 418
Problems/Questions 394 14.3 Colloidal Structure and Stability of
References 395 Colloids 418
14.4 Destabilization of Colloids 421
14.4.1 Double-Layer
13 Aeration, Gas Transfer, and Compression 421
Oxidation 397 14.4.2 Adsorption and Charge
Neutralization 422
14.4.3 Entrapment of Particles in
13.1 Sources of Gases in Water 397
Precipitate 422
13.2 Objectives of Gas Transfer 397
14.4.4 Adsorption and Bridging
13.3 Absorption and Desorption of Gases 398
between Particles 422