USAGE OF AN EXPLOSIVE ATOMIZER IN PROBLEMS OF ENVIRONMENTAL SAFETY - presentation for 9-th High Energy Materials conference (http://www.hems-2013.jp)

1. 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

2. ECOLOGICAL THREATS
o Industrial dusts
o Nanodust
o Smoke of fires
2
HEMs 2013

3. PROBLEM and DESISION
One of decision – to add a liquid
aerosol for acceleration of a
coagulation and sedimentation of the
harmful smoke
3
PROBLEM: difficult sedimentation
of small particles
smoke
The less are particles of the additional
aerosol, the better is the effect
HEMs 2013

4. REQUIREMENTS for SPRAY
High speed of the creation, superfine
dispersion, autonomous, low energy expenses
4
HEMs 2013
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:

5. MODEL of EXPLOSIVE ATOMIZER
• Usage of energy of HEM;
• Hydrodynamic cavitation;
• Ddrop~ 1…10 μm depending
on shock wave pressure.
5
HEMs 2013
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.

6. 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:
6
HEMs 2013
1 2 3
( , )f D t
I 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 D
D Mp
D RTD RTD
I
    
            

(1)
      1
1,0 (1 ) exp - exp -f D a D bD D b D

    
2 20
1 1( , ) 1 ( ).
1
bk n
K D D D D
 
   
  
4 2
0
2
1 ( ) ( ) ( )
18
cr
p K
cr
MD
f pl p allRT D
all
Dp
D MDp G D mdm
e f D dD m t f D dD
dt RT H



   
      
   
  

7. EXPERIMENT
7
HEMs 2013
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).

8. RESULTS
8
HEMs 2013
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

9. 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
HEMs 2013

10. THANK YOU FOR ATTENTION
HAPPY ATOMIZING!
10
HEMs 2013