Page 13 - Air pollution and greenhouse gases from basic concepts to engineering applications for air emission control

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9.5 In-combustion Soot Control . . . . . . . . . . . . . . . . . . . . . . . . 272
9.6 Engine Exhaust Gas Recirculation. . . . . . . . . . . . . . . . . . . . 273
9.7 Practice Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274
References and Further Readings . . . . . . . . . . . . . . . . . . . . . . . . . . 275

10 Post-combustion Air Emission Control. ... .. ... .. ... .. ... .. 277
10.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277
10.2 Control of Particulate Matter Emissions . . . . . . . . . . . . . . . . 277
10.2.1 Electrostatic Precipitator Designs . . . . . . . . . . . . . . 278
10.2.2 Filtration System Designs . . . . . . . . . . . . . . . . . . . 280
10.2.3 Wet Scrubbing. . . . . . . . . . . . . . . . . . . . . . . . . . . 285
10.3 Flue Gas Desulfurization . . . . . . . . . . . . . . . . . . . . . . . . . . 288
10.3.1 Wet FGD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 288
10.3.2 Steam Reactivation of Calcium Based Sorbents . . . . 291
10.3.3 Dry FGD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294
10.3.4 Semi-Dry FGD . . . . . . . . . . . . . . . . . . . . . . . . . . 294
10.4 NO x Reduction Using SCR and SNCR . . . . . . . . . . . . . . . . 295
10.4.1 Selective Catalytic Reduction . . . . . . . . . . . . . . . . 295
10.4.2 SNCR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296
10.4.3 Reagents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297
10.5 Simultaneous Removal of SO x and NO x . ... .. ... .. ... .. 297
10.6 Control of Volatile Organic Compounds . . . . . . . . . . . . . . . 298
10.6.1 Volatile Organic Compounds Adsorption . . . . . . . . 299
10.6.2 Oxidation of VOCs . . . . . . . . . . . . . . . . . . . . . . . 299
10.6.3 Flaring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300
10.6.4 Thermal Oxidizers . . . . . . . . . . . . . . . . . . . . . . . . 300
10.6.5 Catalytic Oxidation . . . . . . . . . . . . . . . . . . . . . . . 303
10.6.6 Other Approaches to Volatile Organic
Compounds Control . . . . . . . . . . . . . . . . . . . . . . . 304
10.7 Control of Soot Particles . . . . . . . . . . . . . . . . . . . . . . . . . . 305
10.8 Control of Trace Metals. . . . . . . . . . . . . . . . . . . . . . . . . . . 305
10.8.1 Mercury in Particulate Control and FGD Devices. . . 306
10.8.2 Mercury Adsorption by Activated Carbon . . . . . . . . 307
10.8.3 Mercury Captured by Metal Oxides, Silicates,
and Fly Ashes ... .. .. ... .. ... .. ... .. ... .. 308
10.9 Proper Layout for Post-combustion Air Pollution Control
Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 308
10.10 Practice Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 309
References and Further Readings . . . . . . . . . . . . . . . . . . . . . . . . . . 311

11 Air Dispersion . ... .. ... .. ... .. .. ... .. ... .. ... .. ... .. 315
11.1 Box Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315
11.2 General Gaussian Dispersion Model . . . . . . . . . . . . . . . . . . 318