dielectric barrier discharge, ozone generation, and their applications (jose l. lopez)
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Dielectric Barrier Discharge, OzoneDielectric Barrier Discharge, OzoneGeneration, and their ApplicationsGeneration, and their Applications
Complex Plasmas Summer Institute 2008Complex Plasmas Summer Institute 2008
Jose L. LopezJose L. Lopez
Saint PeterSaint Peters Colleges College
Department of Applied Science and TechnologyDepartment of Applied Science and Technology
Physics DivisionPhysics Division
Jersey City, New Jersey (USA)Jersey City, New Jersey (USA)
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Faradays Dielectric CapacitorsFaradays Dielectric Capacitors
Faraday's Dielectric Capacitor
(circa 1837)Michael Faraday (1781 1867) Capacitance INCREASED!
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Historical Ozone Tube of W. Siemens (1857)Historical Ozone Tube of W. Siemens (1857)
Werner v. Siemens
Poggendorfs Annalen der Chemie und Physik 102, 66 (1857)
Ozone Production in an Atmospheric-Pressure
Dielectric Barrier Discharge
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Dielectric Barrier DischargeDielectric - Barrier Discharge Configurations
H.E. Wagner, R. Brandenburg, et. al. The barrier discharge: basic properties and
applications to surface treatment. Vacuum. 71 p417-436 (2003).
Dielectric - Barrier Discharge Configurations
HighVoltage
ACGenerator
High VoltageElectrode
GroundElectrode
DielectricBarrier
DielectricBarrier
High VoltageElectrode
GroundElectrode
Discharge
Discharge
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Electric field strengthEof first breakdown 150 Td (p = 1bar, T=300 K)
Voltage Vpp
320 kV
Repetition frequencyf 50 Hz10 kHz
Pressurep 13 bar
Gap distance g 0.25mm
Dielectric material thickness d 0.52mm
Relative dielectric permittivity r
510 (glass)
Typical operational conditions of barrier dischargesTypical operational conditions of barrier discharges
B. Eliasson and U. Kogelschatz.IEEE Transactions Plasma Science. Vol. 19 Issue 6, 1063-1077 (1991)
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Single and double DBD
Single dielectric Double dielectric
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Role of the Dielectric
Serves two functions:
1. Limits the amount of charge transported bya single microdischarge (microplasma)2.
Distributes the microdischarges over the
entire electrode surface area
The dielectric is the key for the proper
functioning of the discharge.
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Microdischarge Activity and U-Q
Lissajous Figure
B. Eliasson and U. Kogelschatz.IEEE Transactions Plasma Science. Vol. 19 Issue 6, 1063-1077 (1991)
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H.E. Wagner, R. Brandenburg, et. al. The barrier discharge: basic properties and applications to
surface treatment. Vacuum. 71: 417-436 (2003).
Many of relevant plasma processes that areof importance to achieving our goal occuron time scales that allow us to study them.
Optical emission spectroscopic studies willallow us to determine the temporal andspatial development of important plasmaspecies such as radicals (OH, NO, variousoxygen radicals) with high time resolution(less than 10 ns) and a spatial resolution on
the scale of mm in the plasma volumefollowing pulsed plasma excitation.
Time scale of the relevant processes of the DBD.
Fundamental Operation of the Dielectric Barrier DischargeFundamental Operation of the Dielectric Barrier Discharge
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Streamer Propagation in 1 bar Air
A.A. Kulikovsky, IEEE Trans. Plasma Sci. 25 439-446 (1997).
Electron Density
Outer Contour Line
ne
= 1010
cm-3
Inner Contour Line
ne
= 1014 cm-3
Fundamental Operation of the DBDFundamental Operation of the DBD
Temporal Development (ns)
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E0
=34 kV/cm
Starting Phase of a Microdischarge (1 bar: 20% CO2 / 80% H2)
1mm
An electron avalanche
propagates towards the anode
ne
=108
cm-3
Numerical Results of Microdischarge Formation
in Dielectric-Barrier Discharges
1010
cm-3
Reverse propagation
towards the cathode
1010
cm-3
ne
=1012
cm-3
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E0
=34 kV/cm
Cathode Layer Formation
1mm
J ust before the peak
of the total current
Numerical Results of Microdischarge Formation
in Dielectric-Barrier Discharges
1010
cm-3
Peak current
1010
cm-3
ne
=1012
cm-3
ne
=109
cm-3
1012
1014
1013
1014
1013
N i l R lt f Mi di h F ti
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ne =109
cm
-3 ne =1014 cm-3
Numerical Results of Microdischarge Formation
in Dielectric-Barrier Discharges
Gap
Local Field Collapse in Area Defined by Surface Discharge
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-- - --- - -CG
CD
-- - -CG
CD
Principals
of
DBD MicrodischargesPrincipalsPrincipals
ofof
DBDDBD MicrodischargesMicrodischarges
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DielectricDielectric--Barrier DischargesBarrier Discharges
Excited Species
Chemical Reactions
Ozone
Generation
Surface
Treatment
Pollution
Control
Excimer
FormationCO2 Lasers
Hydrogenation
of CO2
Excimer Lamps Plasma Displays
Electric Field
Breakdown
Electrons & Ions Discharge Physics
Plasma Chemistry
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Plasma Display TelevisionsPlasma Display Televisions
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AC Plasma Display ConfigurationAC Plasma Display Configuration
PhosphorPhosphor
CoatingCoatingAddress ElectrodesAddress Electrodes
Rear Glass PlateRear Glass Plate
Separator RibsSeparator Ribs
TransparentTransparent
Display ElectrodesDisplay Electrodes
Front Glass PlateFront Glass Plate
DielectricDielectric
BarrierBarrier
MgOMgO LayerLayer
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Generation of OzoneGeneration of Ozone
Y
Z
[
\
3 O2 2 O3
HeatHeatHeatHeat
X
X Power source
Y High voltage electrode
Z Glass, Ceramic or Enamel Dielectric
[ Discharge gap
\ Grounded electrode
OO22 OO33++OO22
Dielectric Barrier Discharge
O O3O2 O2
O2O e O2
O O2eO3
O3O2O2 O2
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Properties of Ozone (O3)
Tri-atomic form of oxygen.
Most powerful commercial oxidizing agent
Unstable -
must be generated and used onsite
Limited solubility in water, but more so than
oxygen
Leaves a dissolved residual which ultimatelyconverts back to oxygen
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Discharge Tubes in Ozone GeneratorsDischarge Tubes in Ozone Generators
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Traditional
Ozone Generator
with Glass Tubes
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Generation of OzoneGeneration of Ozone
O i AO i Ad d T h l
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Ozonia Advanced TechnologyOzonia Advanced Technology
Ozone GeneratorOzone Generator
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Generation of OzoneAdvantages of Enamel Dielectrics
Proven, Patented Design
Simplicity
Single Dielctric Component
Reduced number of Dielectrics
Safety
Lower
operating
voltage
(< 4000 V)
Reliabilty
Fused Dielectris ensure continuous
production
Lowest Power Consumption Operational Savings!
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Modern Ozone GeneratorModern Ozone Generator
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Generation of OzoneGeneration of Ozone
G i f O
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Power Supply Unit
Generation of Ozone
O W TO W T
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Easy to useEasy to use
Low energy usageLow energy usage
Mass transferMass transfer
efficiencies to >efficiencies to >90%90%
Bubble DiffusionBubble Diffusion
Ozone Contacting SystemsOzone Contacting Systems
Ozone Water TreatmentOzone Water Treatment
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Ozone
GeneratorsOzone Contact
Chamber
Vaporizers
LOX Tank
LOX
10-12%
O3
O3/O2
OxygenOff-Gas
Blower
OzoneDestruct Unit
Vent to
Atmosphere
Ozone Process Flow DiagramOzone Process Flow Diagram
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Los Angeles, CA 10,000 1986Fairfax, VA Corbalis 9,000 2003MWD, CA Mills 9,000 2003Fairfax Co., VA Griffith 9,000 2004MWD, CA J ensen 18,750 2005
Indianapolis, IN
Belmont AWT 12,000
2007
Indianapolis, IN
Southport AWT 12,000
2007
MWD, CA
Diemer
13,400
2008
MWD, CA
Weymouth 13,400
2009
Ozonia North America - Potable Water Summary
Total Number of Installations: 90
Total Installed Production: > 265,000 lbs/day
Revision -B
Ozonia Installations Ozone Plant Size [lb/day] Start-Up Date
Key Ozonia Installations (Partial List)
Municipal Ozone Installations
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MWD Mills WTP - California
3 x 3,000 lbs/day of ozone3 x 3,000 lbs/day of ozone
Ozone Water TreatmentOzone Water Treatment
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Oxidant:Oxidant:
Breaks double carbonBreaks double carbon
bondsbonds
Creates OHCreates OH radicalsradicals
which break higher carbonwhich break higher carbon
bondsbonds
Increased temp. and pHIncreased temp. and pH
accelerates Oaccelerates O33decomposition to OHdecomposition to OH
Disinfectant:Disinfectant:
Kills by cellKills by cell lysinglysing ororcausing the cell wall tocausing the cell wall torupturerupture
AttacksAttacks allall bacteriabacteriavirus, cysts and sporesvirus, cysts and sporesin varying degreesin varying degrees
OzoneOzone -- How it works:How it works:
Ozone Water TreatmentOzone Water Treatment
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Micro-organism / DNA
Typical Bacterium DNA
Cellmembrane
Nuclear
material
Capsule
Cell wall
AdenineAdenine
ThymineThymine
CytosineCytosine
GuanineGuanine
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Microbial Growth at Various Ozone
Concentrations
0.004 0.008 0.012 0.016 0.020
Growth likely
Growth possible
NO GROWTH
Ozone concentration (mg/l)
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Typical Water Treatment UsageTypical Water Treatment Usage
Ultra Pure Water 0.05 - 0.25 sec. min.
Water bottling 0.4 1.0 5 10 min.
Swimming pools &spas
0.1 0.75 4 minutes
Potable, taste & odordisinfection
1.5 5.0 5 10 min.
Microfloculation 1.0 3.0 5 10 min.
Lignin & tamminremoval
3.0 10.0 10 30 min.
Municipal wastewater 5.0 15.0+ 15 30 min.
Application O3 mg/l Contact time
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OzoneOzone Municipal ApplicationsMunicipal Applications
Taste and OdorTaste and Odor
Color RemovalColor Removal
Disinfection Without THMDisinfection Without THMss
Improved Filtration Efficiency and FlocculationImproved Filtration Efficiency and Flocculation
Cryptosporidium DeactivationCryptosporidium Deactivation
Giardia & Virus InactivationGiardia & Virus Inactivation
OxidationOxidation -- Organics, Fe & MnOrganics, Fe & Mn
Wastewater disinfectionWastewater disinfection
BOD, COD and TOC reductionBOD, COD and TOC reduction
Ozone Water TreatmentOzone Water Treatment
A li ti f O
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Wastewater Treatment
Disinfection of Secondary and TertiaryEffluents
Color Reduction
TOC Oxidation (Industrial)
Oxidation of Odor Causing Compounds
Oxidation of Endocrine Disruptors (EDCs)and Pharmaceutically Active Compounds(PACs)
Applications of Ozone
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What are Endocrine Disruptors (EDCWhat are Endocrine Disruptors (EDCs) ands) and
Pharmaceutically Active Compounds (PACPharmaceutically Active Compounds (PACs)?s)?
EDCEDCs and PACs and PACs are Naturally and Synthetics are Naturally and Synthetic
compounds that may affect the balance or normalcompounds that may affect the balance or normal
functions in animals and humansfunctions in animals and humans
Applications of Ozone
What can EDCWhat can EDCs and PACs and PACs do?s do?
Even in very small concentrations these compoundsEven in very small concentrations these compoundscancan disruptdisrupt normal bodily functionsnormal bodily functions
ManMan--made chemicals can trick the bodies endocrinemade chemicals can trick the bodies endocrine
systemsystem
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Examples of Endocrine Disruptors
Synthetic HormonesSynthetic Hormones
Naturally Occurring EstrogensNaturally Occurring Estrogens
Health and Beauty AidsHealth and Beauty Aids
SolventsSolvents
PesticidesPesticides
SurfactantsSurfactants
PlasticsPlastics
FungicidesFungicides
1000s of compounds that may be Investigated as
EDCs Some examples are:
Applications of Ozone
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-- Ultrapure Water for Pharmaceutical ApplicationsUltrapure Water for Pharmaceutical Applications
-- Wastewater disinfection / color removalWastewater disinfection / color removal
-- Soil and Groundwater RemediationSoil and Groundwater Remediation
-- Cooling Tower Water TreatmentCooling Tower Water Treatment
-- Food ProcessingFood Processing
-- Aquaculture / AquariumsAquaculture / Aquariums
-- Beverage ApplicationsBeverage Applications
-- Pulp & Paper BleachingPulp & Paper Bleaching
OzoneOzone -- Industrial ApplicationsIndustrial Applications
Ozone Water TreatmentOzone Water Treatment
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High Purity OzonationHigh Purity Ozonation
Microchip manufacturing
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What are the current
issues in large-scale
ozone generation?
E i t l S t
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Front view of the two units after the redesign and reworking of
the gas, water and instruments connections.
Experimental Setup
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Experimental SetupTop view of the twoexperimental units.
Spectroscope (not
shown) is to the left
of the DBD. Theunits were different
with respect to their
electrodes: one had
only the electrode
coated with the
dielectric (single-
coated), the other
one had the
electrode and theanode coated with
the dielectric
(double-coated).
G ti f OG ti f O
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Generation of OzoneGeneration of Ozone
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Spectroscopy
Plasma
Pl Ab i SPl Ab i S
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Plasma Absorption SpectroscopyPlasma Absorption Spectroscopy
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IR spectra in pure oxygen (black curve) and at approximately 10wt% N2
admixture (red line). N2
O5
peaks
appear at 1245 cm-1
and at 1725 cm-1.
Infrared Absorption SpectroscopyInfrared Absorption Spectroscopy
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Infrared Absorption SpectroscopyInfrared Absorption Spectroscopy
IR spectra of several methane variations. The green curve envelopes all of the methane peaks at 1325
cm-1,
recorded at smaller methane admixtures. Simultaneously, the N2
O5
peaks disappear as the methane peaksappear.
N O F tiN O F ti
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N2
O5
FormationN2
O5
Formation
p=2 bara, cw t=20C, q=3.5kW/m2, f=1450Hz
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5 7 9 11 13 15 17
ozone conc. [wt%]
NOxcontent[ppm
V]@3
wt%N2Ble
nding
N2O5 AT95
N2O AT95
N2O5 IGS
N2O IGS
N2O5 LG
N2O LG
Amount of formed N2
O5
and N2
O as a function of ozone concentration at 3 wt% of nitrogen admixture and forvarious electrode arrangements.
Pl E i i S tPl E i i S t
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Plasma Emission SpectroscopyPlasma Emission Spectroscopy
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Relative Emissions of the Ozonizer plasmaRelative Emissions of the Ozonizer plasma
Region 300- 850 nm from ind ividual (calibrated) regions (smoothed by PeakFit). Single-coated ozone generator.
Inlet side.
0.0E+00
5.0E+05
1.0E+06
1.5E+06
2.0E+06
2.5E+06
3.0E+06
3.5E+06
280 300 320 340 360 380 400 420 440 460 480 500 520 540 560 580 600 620 640 660 680 700 720 740 760 780 800 820 840 860
Wavelength, nm
Intensity,a.u.
1
2
3
4
5
6
7 9
8 10
11 12
13
14
15
16
17
Ab l t E i i f th DBD PlAb l t E i i f th DBD Pl
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Absolute Emission of the DBD PlasmaAbsolute Emission of the DBD Plasma
Intensi ties in (O2+3 wt%N2) plasma
0.00E+00
2.00E+03
4.00E+03
6.00E+03
8.00E+03
1.00E+04
1.20E+04
200 250 300 350 400 450 500 550 600 650 700 750 800 850
Wavelength, nm
Intens
ity(a.u.)
Intensities in 3 wt%N2+O2 plasma
O*(777)
Plasma emission diagnostics: role of NPlasma emission diagnostics: role of N
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O N2*
Dry Air
O2 N2e - e -
NO2*
O3 NO
O2 N O2
O3
NO2
N2O
NO3
O2O3
N
NON*
N2O4
NO2O3
NO2
N2O5
NO2
NO3
N
O
O
N
N
Plasma emission diagnostics: role of N2
Plasma emission diagnostics: role of N2
With N2
present
less oxygen
atoms are formed. However,
the difference in intensity is
very small.Modeling of plasma chemistry incl. the NxOy chemistry up to N2O5, fordifferent Oxygen Nitrogen mixtures, varying power deposition scenarios
and initial ozone background concentrations (up to 15%) previously done.
The Role of nitrogen (N ) in o one generationThe Role of nitrogen (N ) in o one generation
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The role of N2 must be related to its by-products reacting on the surface of theelectrode.
The following facts, which were verified on various oxygen-fed ozone generator vessels
(utilized with and without pickling and passivation) were established.
Above 8wt% of O3:
1. Deterioration of the generator performance without N2 admixture, even withp&p; (removal of the p&p oxide layer during aggressive cleaning of surfaces isequivalent to the case without p&p).
2.
The experiments performed by Pontiga et al. in 2004 confirm the above conclusion.The by-products seem to just conserve the properties of a surface; it willdeteriorate without them. A deterioration of the surface is due to oxidation, whichextends the thickness of the oxide layer. N2
O5
is found to deposit as crystallinesubstance on surfaces, which are slightly cooler than the N2
O5
-carrying gas. An
N2
O5
layer seems to inhibit the advanced oxidation of the stainless steel surface.
The role of N2 must be related to its by-products reacting on the surface of theelectrode.
The following facts, which were verified on various oxygen-fed ozone generator vessels
(utilized with and without pickling and passivation) were established.
Above 8wt% of O3:
1. Deterioration of the generator performance without N2 admixture, even withp&p; (removal of the p&p oxide layer during aggressive cleaning of surfaces isequivalent to the case without p&p).
2.
The experiments performed by Pontiga et al. in 2004 confirm the above conclusion.The by-products seem to just conserve the properties of a surface; it willdeteriorate without them. A deterioration of the surface is due to oxidation, whichextends the thickness of the oxide layer. N2
O5
is found to deposit as crystallinesubstance on surfaces, which are slightly cooler than the N2
O5
-carrying gas. An
N2
O5
layer seems to inhibit the advanced oxidation of the stainless steel surface.
The Role of nitrogen (N2
) in ozone generationThe Role of nitrogen (N2
) in ozone generation
The Role of nitrogen (N ) in ozone generationThe Role of nitrogen (N ) in ozone generation
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The Role of nitrogen (N2
) in ozone generationThe Role of nitrogen (N2
) in ozone generation
Three possibilities have to be considered for the oxygen-fedozone generator:
Excited N2 molecules lead to an increased O
2
dissociation; in
such case, an increased efficiency is correlated to the N2
admixture
The by-products perform a chemical/physical process on theelectrodes, which turns out to be beneficial
The UV emission from O2
dissociation that leads to photon or
light splitting of O3
is suppressed by N2
Three possibilities have to be considered for the oxygen-fedozone generator:
Excited N2 molecules lead to an increased O2
dissociation; in
such case, an increased efficiency is correlated to the N2
admixture
The by-products perform a chemical/physical process on theelectrodes, which turns out to be beneficial
The UV emission from O2
dissociation that leads to photon or
light splitting of O3
is suppressed by N2
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Effect of methane on ozone efficiency and specific powerEffect of methane on ozone efficiency and specific power
Effect of Methane on Ozone Content in Outle t Gas and on Specific
Pow er. Pure O2 .
4
5
6
7
8
9
10
11
12
13
0.0E+00 2.0E+03 4.0E+03 6.0E+03 8.0E+03 1.0E+04 1.2E+04
Methane in feedgas , ppm
Ozonec
ontent,wt%
0
2
4
6
8
10
12
Specif
icpower,
kW
h/lb
Ozone content in the outlet gas Specific power of the ozone generator
Eff f N d CHEff f N d CH
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Effects
of
N2
and CH4
Effects
of
N2
and CH4
without
H2O
withH2O
Picture of an amorphous-crystalline N2
O5
structure
captured at the Orlando Skylake water plant in 2006.
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Plasma Chemistry
with
CH4
Impurities
O N2*
OxygenO2 N2
e - e -
NO2*
O3 NO
O2 N O2 O3
NO2
N2O
NO3
O2O3
N
NON*
N2O4
NO2O3
NO2
N2O5
NO2
NO3
N
HNO3
OH
NO2
CH4e-
Effect of methane on electrode surface
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Effect of methane on electrode surface
Electrode of the ozone generator after:
*several hours in CH8
/O2
and up to 2 wt% of methane (a, b, c)
*three hours in CH8
/O2
+traces of N2
and up to 1 wt% of methane (d)
Visible change of discharge character at about 1/3 length of electrode (a, d)
Inlet OutletOutlet
Inlet Inlet
a). b).
c). d).
Ki i f CH C i i h N
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Kinetics
of
CHx
Conversion
withoutN2
O2 + CHx 12wt% O3 + CO2+H2O
conversion by collisions
deposition vaporizationby sputtering
reversible process below 1000ppm CH4
Effect of water on electrode surface with N
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Effect of water on electrode surface with N2
Electrode of the ozone generator after several hours in H2
O/O2
/N2
Inlet
Outlet
Inlet
Effect of water on electrode surface
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Long term effect (800 hrs) of H2O/O2/N2
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Kinetics
of
CHx
Conversion
withN2
O2 + N2 +CHx 12wt%O2 + CO2+H2O + HNO3
conversion by collisionsHNO3 formation
deposition vaporizationby sputtering
irreversible process above a N2 threshold (??)
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Formation of NO and NO2
depends on O3
, N2
and gas temperature.
Conclusion: N2 admixture is the key factor!
Plasma Chemistry
with
CH4
ImpuritiesPlasma Chemistry
with
CH4
Impurities
S
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SummarySummaryThe mechanisms of formed NOx
by-products follows the same
principles as the air fed ozone generators; the amount of formed
N2
O5
is found to depend on just three parameters: ozone concentrationnitrogen admixture
cooling water temperature ( = gas temperature)
The conversion of methane to OH and H2
O is found to depend on:
dissociation by electron impact ( microdischarge)
energy distribution of electrons in the microdischarges (
discharge gap)
The mechanisms of formed NOx
by-products follows the same
principles as the air fed ozone generators; the amount of formed
N2
O5
is found to depend on just three parameters:ozone concentrationozone concentration
nitrogen admixture
cooling water temperature ( = gas temperature)
The conversion of methane to OH and H2
O is found to depend on:
dissociation by electron impact ( microdischarge)
energy distribution of electrons in the microdischarges (
discharge gap)
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How to you optimize
an ozone generator?
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c [wt%]
f [Hz]
q [kW/m2]
c [wt%]
f [Hz]
q [kW/m2]
1.02.8
4.6
6.4
8.2
3.9
10.7
17.6
24.4
0.0
3.0
6.0
9.0
12.0
15.0
18.0
efficiency[%]
power density
[kW/m2]
ozone conc.
[wt%]
( )
[]/CC:][0,parameteradjustable:
[F]sliceisdielectricofecapacitanc:C
[Hz]frequency:f
[V]sliceivoltageminimum:iUmin,
[V]voltagepeak:Upeak
[]cylinderperslicesofamount:n
slicei:i
where
[kW]UUU
1
1Cf4P
iD,iG,i
th
iD,
th
th
n
1i
imin,peakimin,
i
iD,
+
= =
Theoretical Experimental
Scientific
ApproachScientific
Approach
I f P I d i
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Impact of Power Induction
12
3 4
Reference
Arr. B: unstable
Arr. C: -2%Arr. D: +0%
Arr. E: +4.5%Arr. F: +7%
Arr. G: +3%
0.0%
5.0%
10.0%
15.0%
20.0%
25.0%
30.0%
35.0%
40.0%
Fra
ctionofAppliedPowe
Position (1:inlet, 4:outlet)
E i t l T t Ri
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Experimental Test Rig
E i t l T t Ri
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Experimental Test Rig
Outer grounded electrode (left picture) and the
dielectric covered inner electrodes (right).
R f A t
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Reference Arrangement
Inlet OutletGas flow direction
O ti i d A t
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Optimized Arrangement
Inlet OutletGas flow direction
I lli G S (IGS)
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Intelligent Gap System (IGS)
Molecular Oxygen (O2
)
Ozone (O3
)
O2O3
ParticleParticle SizeSize SynthesisSynthesis::
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ByBy--ProductsProducts
Cluster FormationCluster Formationhigh diffusion and deposition to surfaces
low diffusion rate, good transport
high sedimentation on the structure
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C l iC l i
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ConclusionsConclusionsBenefits from DBD Plasma Tailoring:
Reduced power consumption of up to 10%improvement
Increased ozone concentrations of up to
14% now achievable Improved neutralization and conditioning ofdetrimental by-products Reduced system capital and operationalcost!!!
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AckownledgementsAckownledgements
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AckownledgementsAckownledgements
This research was funded in part by the Electro-Energetic
Physics Program of the U.S. Air Force Office of
Scientific Research (AFOSR).
This research was partly funded and
done in collaboration with the
Degremont Technologies
R&D
Spectroscopic and analytical equipment was purchased
through a grant for the National Aeronautics and Space
Administration (NASA) for enhancement of student
research.
This research was funded in part by the American
Chemical Societys Petroleum Research Fund.
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Questions???
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For more information:
Prof. Jose L. Lopez, PhD
Saint Peters College
Department of Applied Science and TechnologyPhysics Division, Gannon Hall
Telephone: (201) 761-6352Email: [email protected]
Thank You!