USAGE OF AN EXPLOSIVE

ATOMIZER IN PROBLEMS OF

ENVIRONMENTAL SAFETY

Olga Kudryashova,

Natalya Korovina, Boris Vorozhtsov

Alexandra Antonnikova, Igor Akhmadeev Institute for Problems of Chemical and Energetic Technologies of the

Siberian Branch of the Russian Academy of Sciences, Biysk, Russia

HEMS

2013 9th High Energy Materials

ECOLOGICAL THREATS

o Industrial dusts

o Nanodust

o Smoke of fires

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PROBLEM and DESISION

One of decision – to add a liquid

aerosol for acceleration of a

coagulation and sedimentation of the

harmful smoke

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PROBLEM: difficult sedimentation

of small particles

smoke The less are particles of the additional

aerosol, the better is the effect

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REQUIREMENTS for SPRAY High speed of the creation, superfine

dispersion, autonomous, low energy expenses

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Ultrasonic nebulizer:

+ Superfine,

- LOW speed,

- Demands an electricity

Pneumatic sprayer:

- TOO large particles,

+ HIGH speed,

+ Autonomous

Destruction of liquid streams: Cavitation:

+ HIGH Speed (< 1 sec),

+ HIGH dispersion (< 10 μm),

+ Autonomy,

+ Low energy (~ 150 J/g).

Decision is to use HEMs:

MODEL of EXPLOSIVE ATOMIZER • Usage of energy of HEM;

• Hydrodynamic cavitation;

• Ddrop~ 1…10 μm depending

on shock wave pressure.

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1 – case, 2 – HEM, 3 – liquid, 4 –

membranes, 5 – reflector, 6 - nozzle

Figure 1 – Scheme of an explosive

atomizer

[1] Olga B. Kudryashova, Boris I. Vorozhtsov, Eugene V. Muravlev, Igor

R. Akhmadeev, Anatoly A. Pavlenko, Sergey S. Titov

Physicomathematical Modeling of Explosive Dispersion of Liquid and

Powders // Propellant, Explosives, Pyrotechnic, 2011, # 36

[2] O.B. Kudryashova, B.I. Vorozhtsov, A.N. Ishmatov, I.R. Akhmadeev,

E.V. Muravlev and A.A. Pavlenko Physicomathematical Modelling of

the Explosion-Induced Generation of Submicron Liquid-Droplet

Aerosols In: Aerosols: Properties, Sources and Management

Practices. New-York: Nova Science Publishers, Inc., 2012

[3] Olga B. Kudryashova, Boris I. Vorozhtsov, Natalja V. Korovina, Igor

R. Akhmadeev, Eugeny V. Muravlev Physicomathematical modelling of

explosive-tpe centrifugal atomizer // Proceeding of the HEM-2011, La-

Rochelle, 2011

[4] O.B. Kudryashova, B.I. Vorozhtsov, N.V. Korovina

Physicomatimatical modeling of pulse atomizer // High energy

materials: demilitarization, antiterrorism and civil application. Abstracts

book of the VI International Workshop HEMs-2012. – Gorniy Altai,

Russia. – 2012.

MODEL of AEROSOL EVOLUTION Smolukhovsky’s equation:

f(D,t) – distribution function by sizes,

D – diameter of particles, t – time,

I1 – decrease of particles with a diameter D because of

collision of particles of diameter D and D1:

K(D,D1) – probability of collisions of particles,

I2 – emergence of particles of diameter D because of

collision of particles with diameters D1 and D-D1:

I3 – reduction of weight of particles because of their

evaporation:

Initial condition for (1):

m – the mass of a droplet; Df – diffusion coefficient;

M – the molecular mass of a liquid droplet; R –

absolute gas constant; T – absolute temperature,

ppl – partial pressure, ρp – particle density, σ –

surface tension, kb – proportionality coefficient; ν –

kinematic viscosity coefficient of the environment,

n0 – initial numerical concentration of particles, δ –

part of an additional phase (index1)

Reduction of an aerosol weight:

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1 2 3

( , )f D tI I I

t

( )

1 1 1

0

( , ) ( , ) ( , )crD t

I f D t K D D f D t dD

2 1 1 1 1

0

1( , ) ( , ) ( , )

2

D

I K D D D f D t f D D t dD

3

4 ( )4 exp 1f pl

p p

M f DD Mp

D RTD RTDI

(1)

11,0 (1 ) exp - exp -f D a D bD D b D

2 201 1( , ) 1 ( ).

1

bk nK D D D D

4 2

0

21 ( ) ( ) ( )

18

cr

p K

cr

MD

f pl p allRT Dall

Dp

D MDp G D mdme f D dD m t f D dD

dt RT H

EXPERIMENT

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Figure 2 – Scheme of experimental installation

Atomizer – airbrush KRATON

R200 LVLP-02S for “harmful fog”

(mass 9 g).

“Harmful” model aerosol –

• sunflower oil,

• 70% water solution of glycerin.

The additional phase (a water

aerosol, α = 2.1, b=0.9) .

Atomizer 2 – explosive atomizer

for additional phase.

Disperse characteristics and

concentration of an aerosol

measured by means of the optical

methods (LID-2M).

RESULTS

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Figure 3 – Dynamics of relative weight of

an aerosol of sunflower oil with an

additional phase of a water aerosol (1)

and without an additional phase (2)

Figure 4 – Dynamics of relative weight of

an aerosol of 70% water solution of

glycerin with an additional phase of a

water aerosol (1) and without an

additional phase (2)

Aerosol Sedimentation time, hrs.

Sunflower oil Glycerin solution Introduction in addition of 5 g of a water

aerosol, D32~5 μm 1.72 1.32

Without introduction of an additional

phase 4.73 3.97

Table – Time of sedimentation of aerosols at introduction of an additional disperse phase and without it

CONCLUSIONS • The usage of an explosive atomizer of a superfine liquid-

drop aerosol for sedimentation of a harmful smoke or dust

is considered.

• The mathematical model of a of kinetics of coagulation and

sedimentation of two-phase aerosol is offered. Additional

phase (superfine water aerosol) is created by use of the

explosive atomizer.

• It is shown that introduction of an additional superfine water

aerosol allows to lower time of sedimentation of an initial

(non-evaporated) aerosol significantly.

• The mathematical model based on the equation of

Smolukhovsky taking into account evaporation,

acceleration of coagulation and sedimentation of two-phase

aerosol cloud describes experimental data well. 9

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THANK YOU FOR ATTENTION

HAPPY ATOMIZING!

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