Application of Submerged Hydrodynamic Cavitating Jets ... · Application of Submerged Hydrodynamic...

www.dynaflow-inc.com AOT 16 11-17-10

Application of Submerged HydrodynamicCavitating Jets (DynaJets®) to Oxidation Of

Organic Compounds in Water

Greg Loraine

November 17, 2010

AOT 16Dynaflow, Inc.

10621-J Iron Bridge RoadJessup, MD

www.dynaflow-inc.com


Outline

Cavitation and Formationof Free Radicals

Acoustic (Ultrasonic)Cavitation vs.Hydrodynamic Cavitation

Hydrodynamic CavitatingJets

Oxidation / Reduction inWater

Applications

Conclusions

Underwater explosion from6000 V spark.Collapse is analogousto cavitation

www.dynaflow-inc.com AOT 16 11-17-10www.dynaflow-inc.com AOT 16 11-17-10

CavitationCavitation

Bubble nuclei in waterexpand & collapse whenthe local pressure changesvery quickly.

Collapsing bubblesproduce tremendouspressures & temperaturesin localized area (~5,200K, ~200 Atm).

Water vapor dissociatesinto OH• and H•

H2O → OH• + H•

Volatile compounds canalso dissociate intoradicalsCCl4 → Cl• + Cl3C

•

Pressure

Radius of Bubble


Reaction Location

Inside collapsing bubbleor at interface

Volatile compounds enterthe expanding bubble anddecompose duringcollapse

OH• and H• concentrationshighest in center, decreasetoward bubble wall

Hydrophobic compoundspartition to air-waterinterface

Local depletion of startingcompound and build up ofproducts

Co

nce

ntr

atio

n

OH• H•

Parent

Products Products

Collapsing Bubble


Hydrodynamic & Ultrasonic CavitationHydrodynamic & Ultrasonic Cavitation

Ultrasonic (US) cavitation produced bymechanical vibration in a liquidlocalized at the face of the probe.

US- high intensity, localized cavitation,energy intensive, scaling up difficult

Hydrodynamic Cavitation (HD) isproduced by motion of fluid.

Large pressure fluctuations in shearlayer of the liquid cause cavitation.

HD – wider area of cavitation, 1/10 –1/100 energy required, easy to scale

US

HD


DYNAJETS® Cavitating Jets

Specially designed nozzles intensifycavitation and generate cavitation atlower pump pressures

This is achieved through:

– Passive acoustic excitation

– Swirling the flow

Both enhance vorticity and reducepressure in the vortices

SSTRATOTRATOJJETET®® DDYNAYNASSWIRLWIRL®®


Hydrodynamic Cavitation for Oxidation

Hydrodynamic cavitation can be 10 – 100 times moreenergy efficient than acoustic cavitation

No addition of oxidizer

Optical opacity or particulates are no problem

Other than nozzle no special equipment required

DYNAJETS®

– Cavitation at lower pressures

– Lower pressures lower electrical requirements

Hydraulic Energy = Flow Rate x Pressure change xtime

– Cavitation in wider area

– Easier to scale up than US


0

0.2

0.4

0.6

0.8

1

0 10 20 30 40Time, Hours

C/C

0P

-Nit

rop

he

no

l

DYNAJETS®

ULTRASONIC

Note Much More Rapid Concentration

Drop with the DYNAJETS ® .

0.01

0.1

1

10

0 5 10 15 20 25 30 35

Time, Hours

Ox

ida

tio

nE

ffic

en

cy

,m

g/M

J

Note High Oxidation Efficency and Short

Oxidation Time for DYNAJETS ® .

DYNAJETS®

ULTRASONIC

Energy: Acoustic & Hydrodynamic

25 ppm p-Nitrophenol

Hydrodynamic cavitation can be 10 – 100 times more energyefficient than acoustic cavitation*

*K.Kalumuck, G. Chahine, J. Fluids Eng., 122,(2000) 465.S. Majumdar, P. S. Kumar, A. Pandit, Ultra. Sonochem., 5 (1998) 113.

K. Jyoti, A. Pandit, Water Res., 38 (2004), 2249.


Applications of DYNAJETS®

Oxidation

– Chlorinated solvents

– Toluene, Acetone

– Pesticides: Malathion, Carbaryl, 2,4-D

– Pharmaceuticals and Personal CareProducts

Disinfection

– Water

– Wastewater

– Storm water

Recovery of Cellular Matter – Algae

Pretreatment of lignocellulose biomass

Biodiesel production

Pump

Reaction Chamber

Dual JetDYNASWIRL® Nozzle


Selectivity of HD Cavitation Oxidation

Volatile (high vapor pressure) can be oxidized easily

pH can be used to adjust degree of ionization of weakacids and bases

Hydrophobic compounds (high octanol-water partitioncoefficient log KOW) oxidize faster than hydrophiliccompounds

Reaction intermediates are formed in regions of highradical concentrations, lower by-product concentrations

Operating parameters (pump pressure, jet velocity, etc.),and nozzle design can be varied to improve oxidationperformance


Volatile Compounds: Mineralization of Chloroform

0

5

10

15

20

25

30

35

40

0 50 100 150 200Time [min]

TO

Cp

pm

2-Jet DYNASWIRL® 65 psi, Chloroform = 344 mg/LVapor Pressure = 160 mm Hg @ 20 C


0

0.5

1

1.5

2

2.5

3

3.5

4

0 10 20 30 40 50 60 70

Oxidation Time (mins)

To

lue

ne

(pp

m)

Oxidation of Toluene

DYNASWIRL® 30 psiToluene:Vapor Pressure= 28.4 mmHg @25 CLog KOW=2.69


0.5

0.6

0.7

0.8

0.9

1

0 20 40 60 80 100 120

Oxidation Time (mins.)

Me

thy

lO

ran

ge

[C]/

[C]0

pH=2.7

pH=2.5

pH=2.4

Hydrophobicity: pH effects & Methyl Orange

Decoloration of acid dye, Methyl Orange –pKa = 3.44

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

1 2 3 4 5

pH

Mo

leF

rac

tio

n

[MO-H]

[MO-]

DYNASWIRL® dual jet 30 psi


0.7

0.75

0.8

0.85

0.9

0.95

1

1.05

0 20 40 60 80 100 120 140

Oxidation Time (mins.)

[C]/

[C]0

Dimethyl methylphosphonate

Malathion

Solubility Effects: DMMP and Malathion

DMMP – dimethyl methylphosphonate,sol = >100g/L, log KOW=-1.88 Vp = <0.1 mmHg

Malathion – organophosphate pesticideSol = 145 mg/L, log KOW=2.89, Vp = 3x10-6 mmHg

Dual Jet DYNASWIRL® at 30 psi


Malathion Oxidation Products

2.93 4.93 6.93 8.93 10.93 12.93 14.93 16.93 18.93 20.93 22.93Time0

100

%

msw30-cl-120 1: Scan EI+TIC

5.16e912.34;99

4.71

127

20.63127

P

OS

O SP

OS

O SP

OS

O SP

OS

P

OS

O S

P

S

OCH2O SOH P

S

OCH2O SP

S

OCH2O SP

S

OCH2O SP

S

OP

S

OCH2O SOH

O

OO

O

CH2CH3

CH2CH3

CH2CH3

O

OO

O

CH2CH3

CH2CH3

O

OOO

OO

CH2CH3

CH2CH3

CH2CH3

O

OO

O

CH2CH3

CH2CH3

CH2CH3

O

OO

O

CH2CH3

CH2CH3

O

OOO

OO

CH2CH3

CH2CH3

CH2CH3

P

O

S

O SP

O

S

O SP

O

S

O SP

O

S

P

O

S

O S

O

OO

O

OH

CH2CH3

O

OOO

OO

OH

CH2CH3

Int. Std–Tributyl phosphate

Malathion

O

OO CH2CH3CH2CH3

OH

OH

O

OOO CH2CH3CH2CH3

OH

OH

CH2CH3

O

OO

OH

O

OOO

OH

P

O

S

CH2O SOH P

O

S

CH2O SP

O

S

CH2O SP

O

S

CH2O SP

O

S

P

O

S

CH2O SOH

P

O

S

O SP

O

S

O SP

O

S

O SP

O

S

P

O

S

O S

GC/MS data from Malathion oxidation: Dual Jet DYNASWIRL® at 30 psi


0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 20 40 60 80 100 120 140

Oxidation Time (mins)

[C]/

[Ma

l]0

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

[C]/

[Ma

l]0

DYNASWIRL® duo jet, 30 psi

Mass Balance Of Malathion Oxidation

Mass Balance

Malathion

Diethyl Fumarate

Hydroxydimethyl Phosphorodithioic Acid

Dimethyl Phosphorodithioic Acid


Selective Oxidation of Mixtures: log KOW

7 pharmaceuticals and personal care products weremixed in wastewater treatment plant effluent

Mixture oxidized using DYNASWIRL® nozzle at60 psi for 30 minutes

Mixture had a range of log KOW values 1.4 – 5.9

More hydrophobic compounds reacted faster


Oxidation of Mixture of PPCP in Wastewater

0.600

0.700

0.800

0.900

1.000

1.100

0 5 10 15 20 25 30

Time (mins.)

C/C

0

Chloroxylenol

Tris (2-chloroethyl)Phosphate

Galaxolide

Mus k Ketone

Oxybenzone

Triclosan

Ibuprofen

DYNASWIRL® nozzle at 60 psi

1.44 3.97

3.79

4.31

4.76

5.9

5.9

Log KOW


Log KOW and Reaction Extent

In a mixture more hydrophobic compounds react faster

y = 0.0523x - 0.0536

R2 = 0.7922

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0 1 2 3 4 5 6 7

log Kow

(1-C

/C0)


Increasing Reaction Rates

Nozzle design

Pressure drop through the nozzle affects thequality of cavitation and oxidation efficiency

Tweeking the system can increase reactionefficiency

DYNASWIRL® nozzle

20 psi 100 psi


Chloramphenicol antibiotic used in aquaculture and veterinary applications

Removal of Chloramphenicol using centerbody CaviJet at 45 and 65 psi

Initial concentrations = 27 mg/l, and total volume 11 liters

Effects of Operating Pressure

0

0.2

0.4

0.6

0.8

1

1.2

0 20 40 60 80 100 120

Cycles

Ch

lora

mp

he

nic

ol[C

]/[C

] 0 65 psi

45 psi


Oxidation with DYNASWIRL®Initial conc = 30 mg/L, Volume = 10 L.

Effect of Pressure Drop on Removal Rate

0

5

10

15

20

25

30

35

0 20 40 60 80 100 120 140

Oxidation Time (minutes)

Ch

lora

mp

he

nic

olm

g/L

30 psi

90 psi

60 psi


Chloramphenicol Removal per kilowatt-hour

0

0.2

0.4

0.6

0.8

1

1.2

0 500 1000 1500 2000 2500

kJ

Ch

lora

mp

he

nic

ol[C

]/[C

] 0 CaviJet 65 psi

CaviJet 45 psi

DynaSwirl 30 psi

DynaSwirl 60 psi

DynaSwirl 90 psi


Conclusions

Cavitation initiated reactions are similar regardless of howthe cavitation is initiated

Hydrodynamic cavitation can be more energy efficient andeasier to scale up than ultrasonic devices

Selective removal of volatile and hydrophobic compoundscan be accomplished

Selective removal by pH adjustment

Oxidation rates have non-linear dependence on pumppressure

Nozzle geometry can effect oxidation rates


Collaboration

www.dynaflow-inc.com, technology descriptionsand papers

Testing, design, and production services

Collaborative research

– Feasibility studies

– Small business STTR

– Grant proposal writing


Acknowledgements & Contact InformationAcknowledgements & Contact Information

DYNAFLOW, INC.www.dynaflow-inc.com

10621-J Iron Bridge Road, Jessup, MD20794. USA

Dr. Greg LoraineSr. Research Scientist

(301) 604-3688

[email protected]

Dr. Georges L. ChahinePresident

(301) [email protected]

Business POC: Dr. Jin-Keun ChoiPrincipal Research Scientist

(301) [email protected]

US Environmental ProtectionAgency

NASA

Office Naval Research

NOAA

NIEHS


Oxidation of As (III) to As(V)

UV/H2O2 & UV/TiO2 data Yoon and Lee 2005

4.60.173DYNAJETS®

17.40.004UV/TiO2

310.004UV/H2O2

kW/1000 galPump Power kWLamp Power kWAOP


Disinfection Efficiency: E coli & BDisinfection Efficiency: E coli & B subtilissubtilis

1.E+00

1.E+01

1.E+02

1.E+03

1.E+04

1.E+05

1.E+06

1.E+07

1.E+08

0 20 40 60 80 100 120

Disinfection Time (mins)

CF

U/m

l

E. coli

B. subtilis

Same conditions - DYNASWIRL® nozzle at 2.1 bar

Effects of nozzle geometry, and nozzle pressure were investigatedusing E. coli and B. subtilis.

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