UNDERSTANDING OZONE When most people think of ozone, they picture the layer high in the earth's outer atmosphere

that protects us from the sun's ultraviolet rays, but this bluish gas, which sometimes can be

detected as a fresh smell after a thunderstorm, is actually a valuable tool with a variety of down-

to-earth uses.

Ozone gas (O3) is a naturally occurring tri-atomic form of oxygen (O2) that is formed as sunlight

passes through the atmosphere or when streaks through the air. It can be generated artificially

by passing high voltage electricity through oxygenated air (corona discharge), causing oxygen

to break apart and recombine in the tri-atomic form.

Because oxygen naturally seeks its normal state, ozone is an unstable, highly reactive form of

the gas. As an oxidizer, it is 51 times as powerful than chlorine, the oxidizer most commonly

used by most food processors, and 3,000 times faster at killing bacteria and other microbes.

Ozone is effective as a disinfectant at relatively low concentrations and does not leave toxic by-

products similar to those related to chlorination.

For more than a century, ozone has been used in Europe for purifying drinking water and is

currently used in the United States for purifying bottled water and decontaminating cooling

towers. The cities of Los Angeles, Dallas, and Las Vegas all currently use ozone to purify their

water supply.

Ozone's reactive nature takes two different chemical pathways, direct and indirect. In the direct

pathway, ozone reacts with unsaturated bonds and causes them to split, especially under acidic

conditions. The indirect pathway requires initiators that break down the ozone even more

rapidly.

Compared to chlorine, ozone offers several advantages for food and beverage processors or

anyone who wants to sanitize materials or surfaces. Chlorine has traditionally been the sanitizer

of choice in the food processing industry, but experts share a growing concern about the

dangerous byproducts such as trihalomethanes or dioxins produced when chlorine reacts with

organic matter in the water. These substances are known carcinogens and are regulated in

drinking water by the U.S. Environmental Protection Agency.

Ozone, on the other hand, is simply oxygen in an unstable and highly reactive form. It naturally

tends to seek its normal state, exhibiting a short half-life as it reverts to oxygen fairly rapidly.

When it reacts with organic matter, it does not form any toxic byproducts and the water in which

it was delivered can be filtered and reused. Because it is so highly reactive, ozone is effective at

controlling or removing biofilms that sometimes form on processing equipment. It can also be

used to reduce biological oxygen demand (BOD), chemical oxygen demand (COD), and

turbidity or other residues in water.

While chlorinated wash systems require transport and storage of potentially hazardous toxic

chemicals, ozone is unique in that it is generated onsite from oxygen and can be produced on

demand with no storage required. When the generator is turned off, there are no dangerous

substances on the premises. While the oxidation reduction potential (ORP) of ozone is affected

by the amount of organic matter or chemicals in the water, its ORP is not as sensitive to

changes in pH as that of chlorine.

Ozone also has a variety of uses in food and beverage processing plants. Water containing low

concentrations of ozone gas can be sprayed onto processing equipment, walls or floors to both

remove and kill bacteria or other organic matter that may be present. Because it has such a

short half-life, ozone does not build up on surfaces the way detergents can if not removed by

proper rinsing.

Ozone can also be injected or dissolved in process waters of all kinds to provide chilling,

fluming, rinsing or washing of food products such as meat, poultry, seafood, fruits or vegetables.

Processors who chill fruits or vegetables after harvest using water held at approximately 34

degrees Fahrenheit can ozonate the water to prevent contamination of the product. Cooling

fruits and vegetables helps slow product respiration, and preserving freshness and quality.

Studies of fruits and vegetables indicate that removing field heat as soon as possible after

harvest is a critical factor in extending product shelf life. As a side benefit, ozone with filtration

can remove particulates, chemicals and organics from water, settling them out by flocculation.

Because it is so effective at removing suspended or dissolved substances, ozone can help

conserve process water by making it possible to filter and recycle the stream.

Ozone is also an effective sanitizer for air and has been used successfully to decontaminate the

atmosphere in storage rooms, containers and other areas. Airborne contaminants are a concern

in some food facilities or clean rooms. Gaseous ozone reacts with unwanted odors or

contaminants in ambient air just as aqueous ozone decontaminates process water. The degree

to which it is effective at destroying contaminants in the atmosphere or on exposed surfaces in

a room depends on the concentration of ozone that can be safely used in the area.

On June 23, 2001, the U.S. Food and Drug Administration officially granted GRAS (Generally

Recognized As Safe) status to ozone for use in food contact applications. While there was

already interest among food processors in the use of ozone for killing microorganisms and

sanitizing equipment, the FDA approval opened up the opportunity for food processors to begin

putting this exciting technology to use in their plants. Today, meat, poultry and seafood and

produce plants are using ozonation as a food safety measure.

For many years now, food and beverage processors in the United States, Mexico, Canada,

Latin America, Europe, Africa, and Asia have installed working ozone wash systems and the

results indicate that bacterial plate counts are lower with ozone as compared to chlorinated

systems.

Fresh food when washed with ozone exhibit a longer shelf life than similar products processed

using chlorine.

Aquentium has theorized that ozone reacts with the enzymes released from damaged lettuce

cells when this vegetable is sliced or shredded. Because the enzymes seem to be deactivated,

natural browning is delayed, not only enhancing shelf life but also preserving color and flavor of

the product. Vegetable and fruit tissues are not injured during contact with ozone water.

Ozone is also proving to be compatible with other disinfectants.

In light of continued outbreaks of food-borne illness and more recent food security concerns in

the United States and internationally, as well as questions about the relative safety of chlorine,

ozone is certainly the desirable solution for enhancing not only the safety but also the quality of

the world food supply.

WHY OZONE?

The potential utility of ozone in the FOOD & BEVERAGE industry depends on the fact that as

an oxidizing agent, it is 1.5 times stronger than chlorine and is effective over a much wider

spectrum of microorganisms than chlorine and other disinfectants.

Ozone kills bacteria such as Escherichia coli, Listeria, and other food pathogens much faster

than traditionally used disinfectants, such as chlorine, and is free of chemical residues. Ozone

is a high-energy molecule. Its half life in water at room temperature is only 20 minutes, and it

decomposes into simple oxygen with no safety concerns about consumption of residual ozone

in the treated food product. It can also be used for recycling water.

For decades, it has been known that ozone is an effective disinfectant and sanitizer for the

treatment of food product. It is commonly used in Europe for treatment of public water systems

and food processing. It is being used in the U.S. for bottled water and many food and other

beverage processing applications.

The benefits of ozone applications in the food industry have been confirmed. Thus, ozone can

successfully replace traditional sanitizing agents to control food pathogens.

Additionally, when Fresh food is washed first by ozonated water, then the wash water can be

recaptured and treated by a combination of ozonation and filtration. The treated wash water is

free of bacteria, color, and suspended solids and can be recycled to reduce water usage.

Unlike conventional chlorine-based washing systems, wastewater discharged by an ozonation

process is free of chemical residues, a growing concern related to the environment and

groundwater pollution. Ozone can also destroy pesticides and chemical residues, such as

chlorinated by-products.

Gaseous ozone is a strong sanitation and fumigation agent and can be used to sanitize foods in

the storage room and during shipping to prevent bacteria, mold, and yeast on the food surface

and to control insects. It can eliminate undesirable flavor produced by bacteria and chemically

remove ethylene gas to slow down the ripening process, thus allowing extended distribution.

In light of continued outbreaks of food-borne illness and more recent food security concerns in

the United States and internationally, as well as questions about the relative safety of chlorine,

ozone is certainly a desirable solution for enhancing not only the safety but also the quality of

the world food supply.

Common Organisms that are Oxidized by Ozone

BACTERIA

Achromobacter butyri NCI-9404

Aeromonas harveyi NC-2

Aeromonas salmonicida NC-1102

Bacillus anthracis

Bacillus cereus

B. coagulans

Bacillus globigii

Bacillus licheniformis

Bacillus megatherium sp.

Bacillus paratyphosus

B. prodigiosus

Bacillus subtilis

B. stearothermophilus

Clostridium botulinum

C. sporogenes

Clostridium tetoni

Cryptosporidium

Coliphage

Corynebacterium diphthriae

Eberthella typhosa

Endamoeba histolica

Escherichia coli

Escherichia coli

Flavorbacterium SP A-3

Leptospira canicola

Listeria

Micrococcus candidus

Micrococcus caseolyticus KM-15

Micrococcus spharaeroides

Mycobacterium leprae

Mycobacterium tuberculosis

Neisseria catarrhalis

Phytomonas tumefaciens

Proteus vulgaris

Pseudomonas aeruginosa

Pseudomonas

FUNGUS & MOLD SPORES

Aspergillus candidus

Aspergillus flavus (yellowish-green)

Aspergillus glaucus (bluish-green)

Aspergillus niger (black)

Aspergillus terreus, saitoi & oryzac

Botrytis allii

Colletotrichum lagenarium

Fusarium oxysporum

Grotrichum

Mucor recomosus A & B (white-gray)

Mucor piriformis

Oospora lactis (white)

Penicillium cyclopium

P. chrysogenum & citrinum

Penicillium digitatum (olive)

Penicillium glaucum

Penicillium expansum (olive)

Penicillium egyptiacum

Penicillium roqueforti (green)

Rhizopus nigricans (black)

Rhizopus stolonifer

PROTOZOA

Paramecium

Nematode eggs

Chlorella vulgaris (Algae)

All Pathogenic and Non-pathogenic forms of Protozoa

FUNGAL PATHONGENS

Alternaria solani

Botrytis cinerea

Fusarium oxysporum

Monilinia fruiticola

fluorscens (bioflims)

Pseudomonas putida

Salmonella choleraesuis

Salmonella enteritidis

Salmonella typhimurium

Salmonella typhosa

Salmonella paratyphi

Sarcina lutea

Seratia marcescens

Shigella dysenteriae

Shigella flexnaria

Shigella paradysenteriae

Spirllum rubrum

Staphylococcus albus

Staphylococcus aureus

Streptococcus 'C'

Streptococcus faecalis

Streptococcus hemolyticus

Streptococcus lactis

Streptococcus salivarius

Streptococcus viridans

Torula rubra

Vibrio alginolyticus & angwillarum

Vibrio clolarae

Vibrio comma

Virrio ichthyodermis NC-407

V. parahaemolyticus

VIRUS

AIDS

Adenovirus (type 7a)

Bacteriophage (E.coli)

Coxackie A9, B3, & B5

Cryptosporidium

Echovirus 1, 5, 12, &29

Encephalomyocarditis

Hepatitis A

GD V11 Virus

Onfectious hepatitis

Influenza

Legionella pneumophila

Polio virus (Poliomyelitus) 1, 2 & 3

Rotavirus

Tobacco mosaic

Vesicular Stomatitis

Monilinia laxa

Pythium ultimum

Phytophthora erythroseptica

Phytophthora parasitica

Rhizoctonia solani

Rhizopus stolonifera

Sclerotium rolfsii

Sclerotinia sclerotiorum

YEAST

Baker's yeast

Candia albicans-all forms

Common yeast cake

saccharomyces cerevisiae

saccharomyces ellipsoideus

saccharomyces sp.

CYSTS

Cryptosporidium parvum

Giardia lamblia

Giardia muris

ALGAE

Chlorella vulgaris

Thamnidium

Trichoderma viride

Verticillium albo-atrum

Verticillium dahliae

Ozone Water Purification

Ozone water purification is the most effective FDA approved water purification method for

eradicating toxins that are found in water. Ozone, also known as O3, is a highly powerful

oxidant that inactivates pesticides, fungus, organic materials, contaminates and viruses

much more potently than chlorine. Ozone water purification accounts for the majority of

purified water in the world; it’s currently the most popular water purification method used.

The Advantages of Ozone Water Purification

Ozone is an excellent disinfectant with the superior ability to kill viruses and biological

contaminants found in water. It is also a very powerful oxidant that can oxidize metals in

water such as manganese, iron and sulfur into insoluble particles, aiding in their filtration

and removal from water. Oxidization by ozone in water purification also aids in removing

taste and odor problems from water much more efficiently than chlorine, and ozone itself

doesn’t produce any odor or taste. Due to the fact that ozone consists of oxygen, it reverts

back to pure oxygen and disappears without a trace after it’s been used. Not only does

ozone remove microorganisms from water, it also halts the accumulation of deposits in

your pipes and water system which greatly improves the quality of your water. Another very

important benefit of water purification using ozone is that no chemicals are added to the

water. Ozone is a naturally occurring substance and when utilized for water purification

purposes it immediately degrades back to oxygen leaving no trace.

How Does Ozone Water Purification Kill Bacteria and Germs

Ozone is composed of three Oxygen atoms. One of the atoms is connected to the others

weakly and will transfer itself to other substances such as viruses and bacteria, causing

them to oxidize by binding itself onto them.

What is Ozone Water Purification?

It is the process of using ozone to purify, that is removing the harmful micro organisms that

can make you sick, from our drinking water. This process has been used in drinking water

plants since 1906 where the first industrial ozonation plant was built in Nice, France and is

more widely used in Europe and Asia than the United States.

Have you ever smelled the clean, fresh scent in the air just after a sudden summer

thunderstorm? ...... That's the ozone!

In this case, you smell ozone, which has been creating from lighting bolts during the

electrical storm. Ozone is also created by the sun’s ultra violet rays reacting with the Earth's

upper atmosphere which creates our protective ozone layer.

At the instant that ozone is created, the oxygen (O2) molecules in the air are broken apart,

by either the suns UV rays or by intense electrical discharge (lightening) and then

recombined with an extra oxygen atom (O3).

Ozone is a very reactive and unstable gas with a short half-life before it reverts back to

oxygen. Ozone is the most powerful and rapid acting oxidizer man can produce, and will

oxidize all bacteria, mold and yeast spores, organic material and viruses given sufficient

exposure. It is said to be:

50 times more powerful than chlorine and

3000 times faster at killing bacteria and other microbes

Does not leave any by-products such as, with chlorine which create trihalomethanes (THM's).

How are Germs and Bacteria killed during Ozone Water Purification?

Ozone is made up of three oxygen atoms (O3)

a "free radical" of oxygen. It will readily give up one atom of oxygen providing a powerful

oxidising agent which is toxic to most waterborne organisms such as bacteria, mold and

yeast spores, viruses or harmful protozoa that form cysts.

This single Oxygen atoms binds with these substance causing them to oxidize (think iron

tuning into Iron Oxide - Rust). The byproduct of this oxidation a single Oxygen atom.

The advantages of using Ozone Water Purification include:

Ozone is primarily a disinfectant that effectively kills biological contaminants.

Ozone also oxidizes and precipitates iron, sulfur, and manganese so they can be filtered out.

Ozone will oxidize and break down many organic chemicals including many

that cause odor and taste problems.

Ozonation produces no taste or odor in the water.

Ozone is made of oxygen and reverts to pure oxygen and it vanishes without a trace once it has been used.

The disadvantages of using Ozone Water Purification include:

The process of creating ozone in the home requires electricity. Loss of power means

no purification.

Ozone is ineffective at removing dissolved minerals and salts.

How Does an Ozone Water Purification System Work?

Ozone is created with what is called an Ozone Generator. It creates O3 in much the same

way as the sun does. AN ELECTRICAL CHARGE converts the oxygen in the air into ozone.

This ozone is then sent through a line into a diffuser, which creates ozone-saturated

bubbles. Water is drawn in to mix with the bubbles, and then fed into the water purification

tank.

The weak Oxygen molecule in the Ozone attaches to other organic molecules in the water

and oxidizies them. This is the oxidation process that was discussed earlier.

It is important to note that the effectiveness of the process is dependent, on good mixing of

ozone with the water, and ozone does not dissolve particularly well, so a well designed

system that exposes all the water to the ozone is important. The Aquentium patented

technology achieves that great result of purified water.

The ozone water purification system is one of the most advanced water treatment processes

in the water industry. Water purified by ozone is now free of protozoa, fungi, germs and

bacteria and is safe for human consumption. Ozone water purification accounts for more

than ninety percent of the world’s purified water and most bottled waters are treated by

ozone.

Aquentium - Ozone Systems - Benefits for Water Treatment:- Disinfection at rates much faster than

Chlorine (E-Coli killed at low Ozone dosages).- Inactivation of viruses.- Removal of Iron and Manganese.-

Control of Tastes and Odors.- Can be used for some pesticide removal in water depending on severity-

Oxidation of Organics and Inorganics- Improves taste, appearance, quality and acceptability of drinking

water.

Systems Are Now Available for Municipal, Well-Water and Domestic Use

Ozonation - What is it?

Ozone is one of the most powerful water treatment compounds available to systems managers today. It

is a technology that has been in continual commercial use for over 100 years and has distinct properties

that allow disinfection of even heavily compromised water streams.

With the 1996 reauthorization of the Safe Drinking Water Act, Ozone was named as among Abest

available technology@ (BAT) for small system compliance to National Primary Drinking water

Regulations as overseen by the US Environmental Protection Agency.

DISINFECTION TREATMENT TECHNOLOGIES LISTED IN THE U.S. ENVIRONMENT PROTECTION

AGENCY=S SURFACE WATER TREATMENT RULE (SWTR)

Ozone - Ozone is a powerful oxidant with high disinfectant capacity. A study found that within a pH

range of 6 to 10, at 3 to 10 C, and with ozone residuals between 0.3 to 2.0 mg/L, bacteriophage MS-2

(a surrogate test organism) and Hepatitis A virus were completely inactivated. Inactivations ranged

from >3.9-log to >6-log, and occurred within very short contact periods (i.e., 5 seconds). A 1992

research report describes treatment studies conducted on MS-2, poliovirus, and Giardia cysts. It found

that MS-2 in natural waters are very sensitive to ozone in comparison to poliovirus type 3. In addition,

Giardia muris and enteric viruses may be inactivated by ozone (as the primary disinfectant) with 5

minutes contact time and ozone residuals of 0.5 to 0.6 mg/L to 3-log and 4-log removals, respectively.

The report concludes that design of ozone as a primary treatment should be based on simple criteria

including ozone residual, competing ozone demands, and a minimum contact time to meet the required

cyst and viral inactivation requirements, in combination with USEPA guidance recommendations. Viral

inactivation CT values for ozone were published in the original USEPA guidance manual for the SWTR.

The EPA has reviewed survey data submitted by the International Ozone Association and found that

ozonation has been applied at many drinking water treatment facilities in the U.S. with capacities

greater than 100,000 gal/day and some smaller facilities, for disinfection as well as for other water

treatment objectives. Applications at the smallest water system size category (i.e., systems serving

<500) are not plentiful. However, ozonation technology for even the smallest public water system

applications is available by Aquentium, and is found to be currently in use in relevant systems. Ozone

treatment, therefore, is a listed technology for all categories of public water systems.

Ozone Small Potable Water Systems

Ozone, the strongest oxidant and disinfectant in commercial use has been employed in over 3,000

large scale municipal plants world-wide. In August 1997, and again in August 1998, the U.S. EPA

identified ozone as a Small System Compliance Technology for existing National Primary Drinking

Water Regulations related to revisions in the 1996 Safe Drinking Water Act. Survey data developed

to support the inclusion of ozone as a "Compliance Technology" identified that over half of the

more than 260 U.S. municipal ozone installations known to be operating in early 1998 are in

systems treating less than 1 MGD (e.g., plants that serve less than 10,000 persons). An additional

363 community, non-community and single family ozone installations using ultraviolet generation

and filtration process also were identified.

Ozone Treatment of Potable Water

Ozonation has been in continuous use in Nice, France since 1906, to ensure disinfection of

mountain stream water. Because ozone is both the strongest oxidant and strongest disinfectant

available for potable water treatment, this unique material can be utilized for a number of specific

water treatment applications, including disinfection, taste and odor control, color removal, iron and

manganese oxidation, H2S removal, nitrite and cyanide destruction, oxidation of many organics

(e.g., phenols, some pesticides, some detergents), algae destruction and removal, and as a

coagulant aid.

Even though ozone is the strongest chemical disinfectant available for water treatment, there are

some refractory organics that it will not oxidize, or will oxidize too slowly to be of practical

significance. In such cases, ozone can be combined with UV radiation and/or hydrogen peroxide to

produce the hydroxyl free radical, HO*, which is an even stronger oxidant than is molecular Ozone,

O3. Deliberate production of the hydroxyl free radical starting with ozone has been termed "Ozone

Advanced Oxidation". Some groundwaters that are contaminated with chlorinated organic solvents

and some refractory hydrocarbons are being treated successfully by ozone advanced oxidation

techniques.

Properties and Generation of Ozone

At ambient temperatures, ozone is an unstable gas, partially soluble in water (generally more

soluble than oxygen). Due to its instability (it quickly reverts to oxygen), ozone cannot be produced

at a central manufacturing site, bottled, shipped and stored prior to use. It must be generated and

applied on-site, as it is required. This means the installation of an ozone production plant at its

point of use B which for small systems can be inside or outside of an individual home.

Ozone is generated for commercial uses either by corona discharge or by ultraviolet radiation. By

the UV technique, rather low concentrations of ozone (below 0.1 wt %) are generated, whereas by

corona discharge, ozone concentrations in the range of 1 - 4.5 wt % are produced when dry air is

fed to the ozone generator. When concentrated oxygen is used as the feed gas, gas phase ozone

concentrations of up to 14 to 18% (by wt) can be produced on commercial scale. Since ozone is only

partially soluble in water, once it has been generated it now must be contacted with water to be

treated in such a manner as to maximize the transfer of ozone from the gas phase into water. For

this purpose, many types of ozone contactors have been developed; all of which are effective for

their designed water treatment purposes. However, as higher concentration ozone gas is employed,

contacting system design becomes more critical due to the lower gas to liquid ratios. Also, the use

of oxygen as the feed gas can result in oxygen super saturation of the treated water causing both

operational problems in following treatment processes and aesthetic in the distribution system.

Ozone contacting system options include atmospheric tall tower or pressurized gas to liquid mass

transfer processes. Fine bubble diffusers, static mixers or venturi injectors can be used to mix the

gas with the water to be treated in either full flow or sidestream configurations. In many small

systems, small in-line injectors and pressurized reaction vessels replace the huge concrete, 20-ft

deep bubble diffuser tanks which are cost-effective in large scale systems.

Once dissolved in water, ozone now is available to act upon water contaminants to accomplish its

intended purposes of disinfection and/or oxidation. At low pH levels (3-6, for example) the ozone is

present primarily in its molecular form (O3). However, as the pH rises, the decomposition of ozone

to produce the hydroxyl free radical (HO*) becomes increasingly rapid. At pH 7 about 50% of the

ozone transferred into water produces HO*. At pH > 10, the conversion of molecular O3 to HO* is

virtually instantaneous.

Engineering Aspects of Ozonation Systems

Because ozone is such a powerful oxidant/disinfectant, the trick to applying it to solve water

treatment problems is to do so in a manner that is effective for water treatment, yet at the same

time ensuring the safety of people in the vicinity. Ozone safety issues are handled quite easily by

use of proper ambient ozone monitoring, tank venting and ozone destruction. In the case of

systems driven solely by a pumping/injector system, Ozone may be produced under vacuum, which

ensures no leakage of Ozone into the operating environment.

The five basic components of an Ozone system include

1. Gas Preparation - either drying gasto a suitable dewpoint or using oxygen concentrators.

2. A suitable electrical power supply.

3. A properly sized Ozone Generator(s)

4. An Ozone contacting system.

5. Ozone off-gasdestruction or suitable venting system.For corona discharge ozone generation, it is

critical to feed the generator a clean and dry oxygen- containing gas. Moisture in the feed gas

causes two operating problems.

First, the amount of ozone produced by application of a given electrical energy level is lowered as

relative humidity rises. Consequently, it is usually cost-effective to dry the air to a recommended

dew point of minus 65'C (-65'C = -76'F) or lower. Second, when ozone is generated using air in the

presence of moisture, the small amount of nitrogen oxides react with the moisture to produce nitric

acid. Moist gas condensation at the cooling/heat transfer surfaces produces the corrosive

compound which can soon cause corrosion problems in the ozone generation equipment, with

concomitant increases in equipment maintenance requirements. Because of the high oxidative

qualities of gas-phase ozone and the chance of moisture from a failing feed gas unit, small system

managers should take extra care to make certain that all components in the ozone generator, ozone

supply line, ozone gas to liquid mass transfer equipment and the contact vessel are ozone-

compatible.

For large scale ozonation systems, the equipment for cleaning and drying feed gases can become

quite complex. For example, effective air drying can involve the multiple treatment steps of air

filtration, compression, cooling, desiccation, and final filtration prior to passage into an operating

corona discharge ozone generator.

For small community systems, several commercial-grade air dryers and small oxygen generators are

available, but these must be matched carefully to the specifications of the ozone generator.

The need for efficient ozone contacting has been discussed earlier, and the final necessity is a unit

for destruction of excess ozone always present in contactor off-gases when generated by corona

discharge. Absent an effective ozone off-gas destruct unit, this excess ozone would be present for

people in the vicinity to breathe, which is not recommended due to its strong oxidizing nature.

Additionally, ozone is heavier than ambient air, can settle in the vicinity, and can attack oxidizable

materials. Destruction of contactor off-gas ozone is readily accomplished thermally (370'C),

catalytically, thermal-catalytically, or (only for small air-fed systems containing very low ozone

concentrations) by passage through granular activated carbon. Care should be exercised in selecting

an ozone destruct method whenever very high concentrations of ozone will be encountered.

To the five-component system outlined above can be added instrumentation and controls for

ensuring the effective and safe operation of the total system. And now the concern for applying

ozone to small water treatment systems becomes one of how to miniaturize the tried and true large

scale units to be effective and affordable systems for treating water in small systems. Aside from

simply making each of the five components smaller in physical size, there are some additional

techniques for corner-cutting without sacrificing quality in terms of production of ozone at

desirable gas-phase concentrations. For electrical power, the home or business wall plug providing

110-V or 220-V single phase power replaces 3-phase supplies at 230, 460 or 575- V required at large

installations.

For air drying, desiccation or oxygen concentration is appropriate as the sole feed gas approach on

small scale, replacing the multiple-treatments required at larger installations. For contacting, small

in-line injectors replace the huge concrete, 20-ft deep bubble diffusers, which are cost-effective on

large scale. In many small applications with extended storage capacity for prolonged ozone

addition, UV generation of ozone can be practical for oxidation of iron and manganese, whereas UV

generation at large water treatment plants is prohibitively higher in cost than corona discharge.

Oxygen concentrators often replace air desiccation units to feed oxygen-enriched air to the ozone

generators, thus producing higher gas phase ozone concentrations and increased output (g/h) per

unit size on small scale, thus avoiding the need for on-site oxygen production and/or storage

facilities

Disinfection with Gaseous Ozonation

The agricultural industry producing edible horticultural crops is very much concerned with

the shelf life of their products. Despite thorough washing and rinsing, one can simply not

completely prevent a decay process and possible infection by human pathogens.

The consumer has demanded produce being of fresh quality and a high safety standard. The

challenge of preserving taste, odor, and extending shelf life significantly, can be met with

gaseous ozonation ( mixing ambient air with ozone gas ). Applying gaseous ozonation today

in a post-harvest environment is accepted by the regulatory agencies. Under the statute of

GRAS (generally recognized as safe), the EPA has allowed ozone as a disinfectant.

While packaged during transport and product in storage, the primary objective with

ozonation is sanitization and extension of shelf life. Since in all of these operations humans

would come in contact with the ozonation process, a controlled and safe environment is

essential.

When using ozone as an anti-microbiological agent, the process of mixing ozone gas with air

and at the same time increasing the relative humidity to a preferred value of above 85

percent, we could also refer to this process as fumigation.

To our advantage are the physical characteristics of ozone having a half-life in the gaseous

phase extending more than 3 days at a temperature around 40oF. Even when packaged in

large bins and in plastic containers, eventually ozone gas will find its way to the surface of

fresh and dried fruits and vegetables. This will occur through forced ventilation but also

through natural osmosis.

Most benefits of applied ozonation in cold storage rooms have been achieved in the

substantial reduction of fungus spore production, elimination of bacterial pathogens, such as

salmonella, e-coli, and shigella, decreased development of ethylene through oxidation, and

significant reduction of listeria monocytogenes.

APPROVALS

INDUSTRY USES -

HOTELS

RESTAURANTS

SCHOOLS

HEALTHCARE

FOOD PROCESSING

BEVERAGE PROCESSING

COMMERCIAL BUILDINGS

CONTACT:

Mark Taggatz, CEO

Tel: 1-951-244-8208

www.aquentium.com

Vice-Presidents

Africa – Mr. George Atkins

Asia –Mr. Robert Hungate

Canada – Mr. Stewart Simpson

Europe – Mr. Otto Parson

South America – Mr. Antonio Portilla