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Transcript of Wet ESP Control of Fine PM and · PDF filez Old, well established technology z Purpose is to...
3/23/2010 1Copyright © Siemens Energy, Inc. 2010
Wet ESP Control of Fine PM and Condensables
James “Buzz”
Reynolds Siemens Environmental Systems & Services
LADCO WorkshopMarch 24, 2009
3/23/2010 2Copyright © Siemens Energy, Inc. 2010
Outline
PM2.5 Regulations
What is PM2.5
Wet ESP Technology
Installations & Results
3/23/2010 3Copyright © Siemens Energy, Inc. 2010
New EPA PM Standards Require Control of PM2.5
New Source Performance Standards for PM - 2/9/06–
24 hr standard is 0.030 lb/MMBtu –
Proposed changing to 0.015 lb/MMBtu
National Ambient Air Quality Standards PM2.5 - 12/20/05–
24 hr standard is 65 µg/m3 24 hr–
Proposed changing to 35 µg/m3
24 hr–
Proposed a new PM10-2.5
70 µg/m3 standard –
Proposed eliminating the existing PM10 standard
Clean Air Visibility Rule (Regional Haze) - 6/15/05–
BART required on sources that impair visibility–
156 Federal Class 1 areas affected –
Controls for NOx, SO2
, PM and VOCs will be required
State Opacity Regulations–
Typically require < 20%
3/23/2010 4Copyright © Siemens Energy, Inc. 2010
What is PM2.5
?
Filterable Particulate–
<2.5 microns in size–
Exists as solid particulate at temperatures of 250°F or higher–
Collected in “front-half”
filter of PM test apparatus–
Represents @ 25% of PM2.5
emitted by sources
Condensable Particulate –
<2.5 microns in size –
Vapors that condense at ambient temperatures•
SO3
– H2
SO4
sulfuric acid mist •
Toxic metals –
cadmium, chromium, lead, magnesium–
Collected in “back-half”
impingers in PM test apparatus –
Represents @ 75% of PM2.5
emitted by sources–
Has not been required to date to meet PM10
standards
3/23/2010 5Copyright © Siemens Energy, Inc. 2010
PM2.5
vs. PM10
3/23/2010 6Copyright © Siemens Energy, Inc. 2010
2.0µm(Bacteria)
8.0µm(Red Blood Cell)
Particle Sizes
40µm(Naked Eye Visibility)
0.3µm(acid mist)
3/23/2010 7Copyright © Siemens Energy, Inc. 2010
Particle
Size
Number of Particles
=1/(4/3πr3)
Compared to 10
microns
Surface Area of Particles= P# * 4πr2
Compared to 10 microns
0.5 128,850,993,811,609 8000x 153,846 20x
1 16,106,374,226,451 1000x 76,923 10x
2.5 1,030,807,950,493 64x 30,769 4x
5 128,850,993,812 8x 15,385 2x10 16,106,374,226 7,692
# of Particles in 1 Cubic Inch
3/23/2010 8Copyright © Siemens Energy, Inc. 2010
Blue Plume Associated with SO3
and PM2.5
3/23/2010 9Copyright © Siemens Energy, Inc. 2010
Opacity is a Function of Particle Size0.5 micron particles are at peak of light extinction curve
3/23/2010 10Copyright © Siemens Energy, Inc. 2010
Point “A”30ppm –SO3100 mg/m3-PM2.5
Point “B”Required 10% Opacity
Point “B1”±94% Removal
SO3
& PM2.5
Determine Opacity
3/23/2010 11Copyright © Siemens Energy, Inc. 2010
Wet Scrubber Removal of PM2.5
3/23/2010 12Copyright © Siemens Energy, Inc. 2010
How to Collect Small Particles
Size in microns
Feet Gravitationa
l Forces
Centrifugal Forces
Electrical Forces
Brownian Forces
10.0 3.28 x10-5 0.024 20.5 0.98 0.0000057
1.0 3.28 x10-6 0.00027 0.235 0.11 0.0000194
0.1 3.28 x10-7 0.0000069 0.0059 0.27 0.0000927
0.01 3.28 x10-8 0.00000053 0.00046 2.12 0.0008540
Particle displacement due to various forces-Buffalo Fan handbook
3/23/2010 13Copyright © Siemens Energy, Inc. 2010
Why Wet Electrostatic Precipitation?
Multi-Pollutant Control–
PM2.5
–
SO3
–
Metals
–
Mercury (species dependent)
Opacity Reduction–
<10% visible plume
Operationally–
Low Pressure Drop –
No Moving Parts–
Self-Cleaning –
Small Footprint–
Flexible to Upset Conditions–
No impact on upstream equipment
A Final Polishing Device
3/23/2010 14Copyright © Siemens Energy, Inc. 2010
BOILERAIR
PREHEATERFGD
SCR
+ -
WESPDRY
ESP/FF
WESP Controls SO3 + PM2.5 + Hg
NOx
PM10Hg
SO2PM10-2.5Hg
SO3PM2.5Hg
NOxSOxPMHg
3/23/2010 15Copyright © Siemens Energy, Inc. 2010
Wet ESP History
First ESP was wet, not dryDeveloped by Dr. Cottrell in 1907Used to control sulfuric acid mistFirst dry ESP was in 1922 at Detroit EdisonThousands of industrial applicationsUtility installations are limited–
3 in US–
2 in Canada–
@ 25 in Japan –
@ 12 in Europe
3/23/2010 16Copyright © Siemens Energy, Inc. 2010
IONIZINGELECTRODE GAS
MOLECULESIONIZED
CORONADISCHARGE
CURRENT METER
HIGH VOLTAGETRANSFORMER
mA
•Gas ions formed by high voltage corona discharge•Particles charged by bombardment of gaseous ions•Ions transport particles to collector•Particle charge given up to collector•Particle trapped in liquid film•Collector continuously cleaned
Wet Precipitation Process
PARTICLEENTERS PARTICLE
COLLECTED
PARTICLECHARGED
PARTICLEIRRIGATEDFROM WESP
COLLECTOR PLATE
CHARGE RETURNS TO TRANSFORMER
1-Charging2-Collection3-Cleaning
3/23/2010 17Copyright © Siemens Energy, Inc. 2010
Wet ESP vs. Dry ESP
OPERATIONAL ISSUES DRY ESP WET ESPBACK CORONA YES NORE-ENTRAINMENT YES NOPM10 REMOVAL YES NOPM2.5 REMOVAL Limited YESSO3 REMOVAL NO YES
MERCURY REMOVAL NO YESWASTE WATER TREATMENT NO YES
3/23/2010 18Copyright © Siemens Energy, Inc. 2010
Condensables-
Temperature Impact
Dry ESP
–
Unsaturated Flue gas
–
After Air Heater
–
~
325 F
Wet ESP
–
Saturated flue gas
–
After FGD
–
~
130 F SO3
Conversion to Sulfuric Acid Vapor (8% moisture)Reference: Estimating Sulfuric Acid Aerosol Emissions from Coal-Fired Power Plants, R. Hardman, et. al.,U. S. Department of Energy-FETC Conference on Formation, Distribution, Impact, and Fate of
Sulfur Trioxide in Utility Flue Gas Streams, March 1998
3/23/2010 19Copyright © Siemens Energy, Inc. 2010
WESP
CLEAN GAS OUT
Scrubber/WESP
Combination
FGD SCRUBBER
3/23/2010 20Copyright © Siemens Energy, Inc. 2010
Collected Liquid to Recycle or Disposal
Horizontal Plate
Type WESP
Plate Irrigation
Inlet Field Outlet Field
3/23/2010 21Copyright © Siemens Energy, Inc. 2010
Industries
Chemical PharmaceuticalPetro-ChemicalTextile/CarpetFood ProcessingMiningSteelFiber OpticsHazardous Waste Soil RemediationArson ForensicsWood ProductsMedical Sterilization
3/23/2010 22Copyright © Siemens Energy, Inc. 2010
Eastman ChemicalKingsport, TN
Hazardous Waste
EPA HWC MACT Issued 1999Phase I -2003*
Equipment -Quench-Scrubber-WESP
3/23/2010 23Copyright © Siemens Energy, Inc. 2010
MACT Test Results
Pollutant Units Test Runs Limits % Particulate gr/dscf, 7%O2 0.0024-0.0030 0.015 99.94
HCL/Cl2 ppmdv, 2.96-4.84 77 99.95
Chromium ug/dscm 39.7-42.8 97 99.97
Lead ug/dscm 3.59-3.85 240 99.95
Mercury ug/dscm 1.82-1.98 130 79%
Dioxin/furan ng TEQ/dscm 0.0131-0.0892 0.4 N/D
3/23/2010 24Copyright © Siemens Energy, Inc. 2010
Kyanite MiningRichmond, Va.
Ore Mining
State RegulationsOpacity <5%
Equipment Supply-Cyclone-Wet Scrubber-Wet ESP
3/23/2010 25Copyright © Siemens Energy, Inc. 2010
Test Results
Pollutant Units Inlet Outlet % SO2 ppm 3580.07 21.4 99.4 ACID MIST (H2SO4)
gr /dscf 0.228 0.0159 93.0
PM2.5 gr /dscf 1.6 0.006 99.6 NOx ppm 41.1 21.5 47.7 CO pm 640.63 581.6 9.2 CONDENSED,INORGANIC
gr/dscf 0.13102 0.0143 89
CONDENSED,ORGANIC
gr/dscf 0.14148 0.01573 90
THC ppm as carbon
225.3 85.5 62
Opacity > 50% <5%
3/23/2010 26Copyright © Siemens Energy, Inc. 2010
First Energy’s Bruce Mansfield Plant
3 x 800 MW UnitsMid-High Sulfur CoalInvestigated Control of: Investigated Control of:
••
PMPM2.52.5
, SO, SO33
, Hg, Hg
••Current Opacity >50%Current Opacity >50%••Opacity Required <20% Opacity Required <20%
3/23/2010 27Copyright © Siemens Energy, Inc. 2010
Minimum Power
Maximum Power
View Through Observation Tube
Effect of increasing power with a fixed SCA
Coal Fired Utility Pilot 19’
Long Site Tube to Simulate Stack Exit
Medium Power
No Power On
Medium Power
Full Power
3/23/2010 28Copyright © Siemens Energy, Inc. 2010
Pilot results plotted on Iso-Opacity Chart
NOV 01 INLET
PM2.5 -
116.0 mg/.m3
SO3 -
10.01 ppmv
NOV 01 OUTLET
PM2.5 -
5.0 mg/.m3
SO3 -
0.85 ppmv
SEP 01 INLET
PM2.5 -
67 mg/m3
SO3 -
11.50 ppmv
SEP 01 OUTLET
PM2.5 –
14.4mg/m3
SO3 –
2.70 ppmv
NOV 02 INLET
PM2.5 -
115.0 mg/.m3
SO3 -
8.90 ppmv
NOV 02 OUTLET
PM2.5 -
5.0 mg/.m3
SO3 -
2.90 ppmv
3/23/2010 29Copyright © Siemens Energy, Inc. 2010
Summary
Wet Electrostatic Precipitation Technology:
Old, well established technology Purpose is to capture PM2.5- solid particulate, acid mists, metals including some mercuryOperates in a saturated, wet environment after a wet scrubberInstalled in a variety of industries Very high removal efficiencies possible > 95% Low maintenance & pressure drop