Transcript Ozone in nature Ozone is naturally produced by ultra-violet rays

January, 2013
Ozone in nature
Ozone is naturally produced by ultra-violet
rays from the Sun and lightning-based
corona discharge.
These two methods account for nearly all
natural ozone creation on Earth.
Why sky looks blue?
Ozone Formation via Corona
Discharge
An electrical discharge (a spark) splits an oxygen
molecule into two oxygen atoms. (Electrical discharge is
also referred to as corona discharge.) These unstable
oxygen atoms combine with other oxygen molecules.
This combination forms ozone.
Ozone Generators use the Same
Methods
Oxygen is forced between high voltage plates
to simulate corona discharge. The oxygen is
broken apart and recombines into ozone
Ozone Generator construction
Scheme
Ozone and Oxygen Properties
Property
Ozone
Oxygen
Molecular Weight
48
32
Color
light blue
colorless
Smell
smell after lightning
storms
odorless
Solubility in water(0oC)
0.64
0.049
Density (g/l)
2.144
1.429
Oxidizing Potential (Volts) 2.07
1.23
Ozone is one of the most powerful oxidants used in water & air applications.
Typical Ozone half-life
Gaseous
Temperature
(C)
Half-life
-50
3 months
-35
18 days
-25
8 days
20
3 days
120
250
Dissolved in Water
Temperature
(C)
Half-life
15
30 minutes
20
20 minutes
25
15 minutes
1.5 hours
30
12 minutes
1.5 seconds
35
8 minutes
Oxidizing Potential of Various
Reagents
Reagent
Oxidizing Potential
Ozone
Hydrogen Peroxide
Permanganate
Chlore
2.07
1.77
1.67
1.36
Oxygen
1.23
Effect of Ozone on Bacteria
1. A healthy
bacillus bacterial
cell
4. A newly created hole
in the cell wall has
injured the bacterium.
2. An ozone
molecule (blue)
comes into contact
with the cell wall
5. The bacterium begins
to loose its shape while
ozone molecules
continue creating holes
in the cell wall.
3. As ozone molecules
make contact with the
cell wall, a reaction
called an oxidative
burst occurs which
literally creates a tiny
hole in the cell wall.
6.After thousands of
ozone collisions over only
a few seconds, the
bacterial wall can no
longer maintain its shape
and the cell dies
Ozone Compatible Materials
Materials
Stainless steel
Theoretical rating (Cole Parmer)
Excelent
Aluminum
Good
Bronze
Good
Nitrila
Not recommended
Cooper
Excelent
Metal
Not recommended
Natural rubber
Not recommended
Neilone
Not recommended
Polycarbonate
Excelent
Polypropelene
Good
Teflon
PVC
Silicone
Zinc
Excelent
Good
Excelent
Not recommended
Ozone Odor Destruction
Ozone reacts with a foreign odor to change is composition so it
is no longer the same odor. A new molecule is formed but this
new molecule is typically less odorous that the original one.
When ozone makes contact with the odor molecule,
the odor is destroyed, but so is the ozone molecule.
Stronger odors mean more odor molecules present
- therefore more ozone is also needed.
Ozone Readily Destroys the Following
Odors:
•
•
•
•
•
•
•
•
musty (molds) odor;
smoke odor, after fire odor;
“sick house sindrom”;
pet odord;
fecal odors;
cooking odors;
medicamente use odors;
urine odors.
NB! Ozone will not mask odors - It destroys them!
Advantages of Ozone
•Ozone is the strongest oxidant and disinfectant available for the treatment of
aqueous solutions and gaseous mixtures.
•Although ozone is only partially soluble in water, it is sufficiently soluble and stable
such that its oxidation or disinfectant properties can be fully utilized.
•After ozone oxidizes or disinfects, it decomposes into oxygen.
•Ozone reacts with a large variety of organic compounds resulting in oxygencontaining organic by-products.
•Although ozone is the strongest oxidizing agent commercially available, it is safe to
handle. The primary reason is that it cannot be stored and, therefore must be
generated and used on-site.
•Ozone in its gaseous phase is a proven deodorizer for a variety of odorous materials.
•In treating potable water, wastewater, and landfill leachate, ozone has the proven
ability to convert biorefractory organic materials to biodegradable materials. As a
result, combining ozone oxidation with subsequent biological treatment can produce
water or wastewater with lower concentrations of problematic organic compounds
more cost-effectively than either process used individually.
•Applying ozone to any medium (liquid or gaseous) does not add other chemicals.
•Ozone, by itself, does not affect pH (ozone can oxidize the contaminants which are
causing a pH adjustment)
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www.ozonalietas.lv
Juris Brūveris - Member of Board
E-mail: [email protected]
Phone: +371 29223654