POLLUTED EMISSION TREATMENTS FROM INCINERATOR GASES Ecole Nationale Supérieure de Chimie Avenue du Général Leclerc, Campus de Beaulieu 35700 Rennes, France Tel 33 (0)2 23 23 80 02 Fax 33 (0)2 23 23 81 11 e-mail Pierre.Le-Cloirec@ensc-rennes.fr
POLLUTED EMISSION TREATMENTS FROM INCINERATOR GASES Ecole Nationale Supérieure de Chimie Avenue du Général Leclerc, Campus de Beaulieu 35700 Rennes, France Tel 33 (0)2 23 23 80 02 Fax 33 (0)2 23 23 81 11 e-mail Pierre.Le-Cloirec@ensc-rennes.fr
Waste Primary combustion chamber External Heating 1000 C Post-combustion chamber ENERGY RECOVERY 240 C Flue Gas Fly ash Activated Carbon Base agent Air Pre-Heater 80 C 50 C Lime Post heating 320 C NH 3 Air Fly ash Slug INCINERATOR ELECTROSTATIC PRECIPITATTOR BAGHOUSE FILTERS WET SCRUBBER SCR - CAT REACTOR (adapted from Fino et al., 2005)
Waste Primary combustion chamber External Heating 1000 C Post-combustion chamber ENERGY RECOVERY 240 C Flue Gas Fly ash Activated Carbon Base agent Air Pre-Heater 80 C 50 C Lime Post heating 320 C NH 3 Air Fly ash Slug INCINERATOR ELECTROSTATIC PRECIPITATTOR BAGHOUSE FILTERS WET SCRUBBER SCR - CAT REACTOR (adapted from Fino et al., 2005)
Energy recovery
Waste Primary combustion chamber External Heating 1000 C Post-combustion chamber ENERGY RECOVERY 240 C Flue Gas Fly ash Activated Carbon Base agent Air Pre-Heater 80 C 50 C Lime Post heating 320 C NH 3 Air Fly ash Slug INCINERATOR ELECTROSTATIC PRECIPITATTOR BAGHOUSE FILTERS WET SCRUBBER SCR - CAT REACTOR (adapted from Fino et al., 2005)
Particule size X Rays UV Visible IR micro-waves, radar smokes fumes fly ashes soots pollen virus bacteria hair macromolecule dust molecules smog cloud -fog drizzle rain 10-6 0.0001 0.01 1 100 10 4 1 Å 1 nm 1 m 1mm Taille ( m)
Electrostatic precipitator Coulson-Richardson, 1997
Electrostatic precipitator Efficiency (%) Particle size ( m) Techniques de l Ingénieur - Génie des Procédés
Electrostatic precipitator High voltage Collector plates Hoppers Technique de l Ingénieur - Génie des Procédés
Electrostatic precipitator Tredi Groupe Séché, France
Filtration mechanisms For an isolated single sphere: Mode of action of the basic mechanisms: A Interception B A U B C Sedimentation Diffusion - Adsorption C Particle trajectory Streamline
D. Thomas, 2005 Particle aggregates on fibers Particle diameter = 2.6 m
D. Thomas, 2005 Particle dendrites Particle diameter = 0.15 m
Efficiency Total Removal D. Thomas, 2005 Particle diameter
General view of «Bag House» Coulson-Richardson, 1997
Industrial system example
Cyclone Gas inlet Gas outlet Vortex breaker Dust collector Dust outlet Techniques de l Ingénieur - Génie des Procédés
Waste Primary combustion chamber External Heating 1000 C Post-combustion chamber ENERGY RECOVERY 240 C Flue Gas DeNox Fly ash Activated Carbon Base agent Air Pre-Heater 80 C 50 C Lime Post heating 320 C NH 3 Air Fly ash Slug INCINERATOR ELECTROSTATIC PRECIPITATTOR BAGHOUSE FILTERS WET SCRUBBER SCR - CAT REACTOR (adapted from Fino et al., 2005)
DeNox NO 2 or NO N 2 N 2 NH 3
DeNox 4NO + 4NH 3 + O 2 --Catalyst ---> 4N 2 + 6H 2 O 2NO 2 + 4NH 3 + O 2 --Catalyst ---> 3N 2 + 6H 2 O
DeNOx Inert support Alumino silicate Zeolites Metal Pt Pd, V, Zr...
NOx removal
Waste Primary combustion chamber External Heating 1000 C Post-combustion chamber ENERGY RECOVERY 240 C Flue Gas Fly ash Activated Carbon Base agent Air Pre-Heater 80 C 50 C Lime Post heating 320 C NH 3 Air Fly ash Slug INCINERATOR ELECTROSTATIC PRECIPITATTOR BAGHOUSE FILTERS WET SCRUBBER SCR - CAT REACTOR (adapted from Fino et al., 2005)
Gas - Liquid transfer Gas Liquid
Absorption with reaction Gas G-L Interface Liquid Chemical reaction A --> B
Spray column Packed column
Spray Column Spray column coalescer Air outlet Washing solution inlet Air inlet Fresh solution Washing solution outlet Recirculation pump
Packed column Air OUTLET Packing materials Air INLET Fresh solution Washing solution Recirculation pump
Some packing materials
Absorption Acid (H 2 SO 4 ) Base (NaOH) CO 2 Oxidant (NaOCl, O 3 ) Liquid solutions s
Practical industrial design Velocity : 500-1000 m/h Residence time : 0,1-10 s Air temperature : 10-80 C Concentration : 1-50 000 mg/m 3 Pressure drop : 0,1-1 m d H 2 O
An Industrial Example
Waste Primary combustion chamber External Heating 1000 C Post-combustion chamber ENERGY RECOVERY 240 C Flue Gas Fly ash Activated Carbon Base agent Air Pre-Heater 80 C 50 C Lime Post heating 320 C NH 3 Air Fly ash Slug INCINERATOR ELECTROSTATIC PRECIPITATTOR BAGHOUSE FILTERS WET SCRUBBER SCR - CAT REACTOR (adapted from Fino et al., 2005)
Activated carbon Before activation Some strongly activated areas Duber et al, Fuel Proces. Technol 77-78 (2002), 221-227
Activated carbon characteristics Pore diameter nm dp - Macropores > 50 - Mesopores 2 < d < 50 - Micropores < 2 Porous volume cm 3 /g Vp 0.3 0.7 Specific surface area (BET) m 2 /g S BET - non activated 2-20 - activated 500-2000
Principle of adsorption
Adsorption capacity Adsorption capacity (%) 100 10 20 C 80 C q q 1 n qe KC e e e bqmc 1 bc bqmc 1 bc e e 1 n e 1 n e 1 0,1 1 10 100 ) 3 Concentration at equilibrium (g/m q e f (C e )
Breakthrough curve z 0 C 0 C 0 C 0 C 0 C 0 time saturated zone adsorption zone C/C 0 1 adsorption wave 0 tb time
Activated carbon grain filter Adsorbant Steam inlet for regneration INLET Steam outlet
Modelling t b C t C N 0 1 0 U 0 Ae1 n C 0 z rt z 1 n 0 1
Purpose Solid phase mass balance Modeling breakthrough curves Homogeneous surface diffusion model Equation t D q s 2 2 r r r q r Initial condition q 0 0 r R, t 0 Boundary conditions q t q t 0 a r 0, t s 0 k f C(t) Cs (t) D (r R, t) Liquid phase mass balance C C 3k f 1 V C C z t R Initial condition C 0 0 z H, t Boundary condition C C0(t) z 0, t 0 s Freundlich isotherm equation 1 q K C (t) n r R, t S
POLLUTED EMISSION TREATMENTS FROM INCINERATOR GASES Ecole Nationale Supérieure de Chimie Avenue du Général Leclerc, Campus de Beaulieu 35700 Rennes, France Tel 33 (0)2 23 23 80 02 Fax 33 (0)2 23 23 81 11 e-mail Pierre.Le-Cloirec@ensc-rennes.fr