The document describes Regenerative Activated Coke Technology (ReACT), an advanced multi-pollutant control system using activated coke. Key points: 1) ReACT uses activated coke to adsorb SO2, SO3, NOx and mercury from flue gases, providing over 95% SO2 control and co-benefits for other pollutants. 2) The activated coke is then thermally regenerated in a regenerator, releasing an SO2-rich gas for acid production while regenerating the coke for further adsorption. 3) ReACT provides a fully dry, regenerative system with minimal waste and reagent needs for effective multi-pollutant control from

1. Regenerative Activated Coke Technology
ReACTtm
Advanced Multi-Pollutant Control Technology
Hamon Research-Cottrell

2. Hamon Research-Cottrell
Particulate Control
Low pressure High Volume pulse jet filters
Electrostatic Precipitators
Recent Clients
NOx control
SNCR Utilities
U2A Urea to Ammonia systems Pacificorp
FGD and multipollutant control
Arizona Public Service Refineries
Nevada Power
Refinery Scrubbers (ExxonMobil WGS) ExxonMobil
Tri-States Generation
Dry systems (J-Power Entech ReACT) Shell
Minnesota Power
Conoco Phillips
Dairyland Power
Valero
Consumers Energy
BP
Alliant Energy
Marathon
Dominion Energy
PEMEX
Pennsylvania Power & Light
Tesoro
Mirant
Syncrude
Detroit Edison
Duke Energy
Florida Power & Light

3. Old 2x265MW
New 2x600MW
230m (750ft )
Isogo
Power
ReACT
480m (1580ft )
ReACT
Station

4. ReACT System Flow
Adsorption Regeneration By-Product Recovery
Activated Coke AC
AC
Lock
Hopper
Regenerator
*1 *2 NH3 Hot
Air By-Product
SO2 Rich Gas Off-Gas *1
Recovery Unit
Exhaust Gas Adsorber Clean Gas
Hot
*3
Stack Gas
BUF
*2
AC Hopper By-Product
Air
Lock
Furnace Fuel
AC Hopper
Particulates
AC Fines
Separator
*3
Balance of plant systems not shown
Ammonia supply
Nitrogen
Acid plant

5. ReACT
Typical Layout
Two adsorber casings
Two - four regenerators
Regenerator auxiliaries
600 MW fits in one acre plot

6. Isogo Unit #1 (2002)

7. Adsorption and reaction on activated coke
SO2 and SO3 are adsorbed at high efficiency on the activated coke surfaces
as sulfuric acid ,ammonium sulfate, and ammonium bisulfate.
SO2 + H2O + 1/2 O2 H2SO4*
SO3 + H2O H2SO4*
H2SO4* + NH3 NH4HSO4*
NH4HSO4* + NH3 (NH4)2SO4*
(* denotes adsorbed species)
The catalytic effect of activated carbon also leads to reduction reactions to reduce NOx in
the presence of ammonia. The NOx control activity is completed in the adsorber.
NO + NH3 + 1/4 O2 N2 + 3/2 H2O
NO + C..R N2
(C..R epresents a surface functional site)

8. Adsorber
Activated Coke Bed
Activated
Coke Inlet
Sub Louver
Perforated
Plate
Flue Gas Inlet Flue Gas Outlet
Inlet Louver
Sub Louver
Inlet Louver
Activated Coke Bed Perforated
Plate
Roll Feeder
Activated
Coke Outlet

9. Thermal regeneration of activated coke
At the temperatures in the regenerator heating section adsorbed sulfuric acid ,ammonium
sulfate, and ammonium bisulfate are decomposed to SO2.
Activated coke pellets enters via lock hoppers and is in gravity counterflow against
desorbed gases and N2 carrier gas.
Sulfur rich gas containing SO2, CO2, N2 and H2O exits the regenerator to an acid plant
under its own pressure.
H2SO4* + 1/2 C SO2 + 1/2 CO2 + H2O
(NH4)2SO4* SO3 + NH3 + 2 H2O
NH4HSO4* SO3 + 2 NH3 + H2O
3 SO3 + 2 NH3 3 SO2 + 3 H2O + N2
(* denotes adsorbed species)
Non isothermal desorption kinetics show
peak rates at 300C and completion by 450C

10. ReACTtm Advanced multi-pollutant control technology
Activated coke quality
Initial charge – high activity
Make up – lower activity allows wider sourcing
Steady state AC develops over time
Activity improves with use
With successive regeneration cycles
General material size decreases to a steady
state and total surface per unit bed volume
Residual sulfur, oxygen and ammonia functional
groups accumulate on the used surfaces
New pores open as some carbon is used in
H2SO4 -> SO2 reactions
Resulting SOx, NOx, and Hg activity increases
Fines separation at base of regenerator
Activated coke is discharged through a lock
hopper to fines separation
Hg free fines can be burned for fuel value
Nominal AC fines loss ~1% of AC circulation

11. ReACTtm Advanced multi-pollutant control technology
Fully dry adsorption based system
no water evaporated into flue gas, (water at 1% of WFGD, DFGD)
no sprays, no slurry preparation
no water vapor plume, no acid plume
SOx
>>95% SO2 control
near zero SO3 emission
carbon steel flue gas path including stack
NOx
Nominal 20-40% control as co-benefit for compliance or for NOx credits
can boost to >60% with incremental NH3
Net PM reduction
Additional collection of fine particulates and trace metals
Hg control with waste volume minimization
95% control of both elemental and oxidized forms as co-benefit
Hg waste volume minimized (<0.1 ton/MW/year)
Thermal regenerative system
Reduced reagent and disposal material volume
Sulfur rich gases go to acid plant producing significant byproduct revenue

12. Regenerative Activated Coke Technology
ReACT
Advanced
Integrated Multi-Pollutant
Control Technology