Ozone Assist for Rainwater RO System Ozone Plus RO for Potable Rainwater

In this post, I introduce a working concept for a low-cost, 400 gallon per day water harvesting system built as much as possible with recycled materials and local equipment. The goal of this project is to empower families, tribes, and small communities with the knowledge and resources needed to take control of providing safe drinking water. This water treatment system is the brainchild of Clint Elston who has worked tirelessly his whole life gathering ideas and developing practical solutions. My expertise is in the ozone treatment component.



Proven Environmental Water & Wastewater Solutions for Worldwide Health & Economic Development Video

Ozone destroys harmful bacteria and breaks down organics in the water so they can be more easily removed. The ozone assists the RO filter, enabling it to operate without wasting the drain water needed to rinse contaminants from the filter.

The four barrel system

Water collection vessel – Rainwater/grey water is collected in the white 275 gallon tote. This tote simply serves as a reservoir for water collection. Any large water collection device can work.

Dirty Circulation pump (right) for the dirty water loop (yellow/green) pulls “dirty” water from this tank, picks up waste RO water, picks up ozonated water, and fills/tops off barrel #1 in the 4 barrel system before returning any leftover water to the rain tank. If only one pump is available, it is possible to use this pump for the clean water loop as well. See diagram.

Clean Circulation pump (left) for the clean water loop pulls pre-treated water from barrel #4. This water has been treated with ozone and much of the sediment settled out to the bottom of the first three barrels. This clarified water is pumped to two locations: 1) through a venturi for ozone injection and 2) a reverse osmosis filter.

Ozone injection – Ozone is a naturally occurring gas made with oxygen and electricity. A high voltage discharge breaks the bond between the two oxygen atoms of an oxygen molecule and the free oxygen bonds with other unbroken oxygen molecules to form an ozone molecule of 3 oxygen atoms. This high energy form or oxygen quickly and naturally destroys pathogens and water contaminants. A 4 gram/hour flow of ozone at a concentration of about 7 grams/cubic meter is pulled from the ozone generator through tubing into a venturi which injects the ozone into the water stream. The ozone is needed to control bacteria and pathogens as well as oxidize organics and other contaminants. The oxidation prevents the buildup of biofilm in the RO filter.

Four Barrels – The ozone serves to kill bacteria and to oxidize contaminants helping them settle out. The ozonated water enters the bottom of barrel #1 (off-gas, reaction, settling) where the excess ozone is able to off-gas. Ozone treated water moves from the top of the first tank to the bottom of barrel #2. (reaction, settling, clarifying) Barrel #2 finishes ozone reaction and continues settling of heavier contaminants. Clarified water exits the top and enters the top of barrel #3 & #4 (Settling stage one, settling stage 2). The primary function of tanks #3 & 4 is settling and clarification.

Reverse Osmosis Filter – Layers of soil and years of time naturally filter water in deep aquifers. A reverse osmosis (RO) filter is a very compact and quick way to provide potable water. For this water recycling system, we recommend the iSpring RCS5T 500 GPD Residential and Light Commercial Tankless Reverse Osmosis Water Filter System with Side-Flow™ technology and 1:1 Drain Ratio. The RO filter removes the very fine particles and remaining contaminants that did not get removed in the barrels.

Pressure Tank – The RO filter includes a booster pump to provide the pressure needed for RO filtration. Filtered water is stored in the 80-gallon pressure tank. RO wastewater is returned to the dirty water circulation loop. Where further ozone treatment helps these contaminants to break down further or settle out.

Ozone Generators – The market has been flooded with small ozone generators and exaggerated performance claims. Most of them would not work well for this application or produce the concentration of ozone needed. Unfortunately, a quality ozone generator that would give years of trouble-free service is costly. Getting one of these quality generators may be especially difficult in countries where a system like this is needed most. I am optimistic, however, that adequate generators can be built using common and even recycled components for a minimal cost. They might not be very compact or efficient, but it may be the best we can do at this time. I believe with some research, pooling of ideas, and diligence, we can come up with some great options for this water treatment system. Sharing ideas or links to ozone generator builds is welcome.

Clean Dry Air – Having a source of clean, dry, air for ozone generators can not be overemphasized. Moisture in an ozone generator produces nitric acid which corrodes and destroys ozone reactors. Desiccant is an effective and cheap way to provide this dry air. The desiccant needs to be dried out with heat. I have ideas for a solar desiccant dryer, but would like to know if anyone has ever tried this or seen it work? We sell a small desiccant dryer that needs to be manually dried out in a low oven, and we also have an automatic one that dries out the desiccant with electric heating elements.

I look forward to ideas for DIY ozone generators and air dryers. I hope to share some ideas of my own in future posts.

How to Install a Venturi Wrong: Learning to Harness Ozone and Venturi Injection Principles to Clean up Dirty Well Water

So a customer puts up a new house in the country. Water is supplied by well from an old house that had been on the site. Unfortunately, the well is pushing up some sediment and bacterial contamination.  One possible solution is to put in a new, deeper well in the hopes of finding cleaner water.  Another, much less expensive solution is to use filtration and harness the power of ozone to purify the water.

The simplest setup includes a Mazzei Venturi which uses the existing water flow to pull ozone into the water stream.  A small mixing tank would increase contact time for disinfection before use in the home.

This would be a perfect project for me, the apprentice.  I put the system together and brought it out for the install.  Having worked in our shop putting together a number of industrial systems, I was confident it would work well.  Plumbing was complete.  I flipped the pump breaker switch and water began flowing.  My balance barometer indicated some suction and the ozone generator light kicked on …. and then it turned off again as the water pressure increased.  What was wrong?

A Mazzei Venturi injector is at the heart of this system.   The small plastic Venturis we often use are very simple, but the careful and precise design makes them very reliable and effective.    Essentially they use some of the energy from the water flow to create a suction that will pull a gas into the water stream.  Two pressure gauges, one before the Venturi and one after the Venturi will demonstrate this loss of energy in the water flow.  The lost energy is being used to pull gas into the water stream.   Injectors need to be built to fit specific water flows and pressure.  Your water flow in gpm and pressure requirements will help determine which injector will work.  Mazzei has a chart for each type of injector that will tell how much gas flow is created for a range of pressures.

So, back to my system install and what was wrong.  When I referenced my pressures before and after the injector to the Mazzei chart, I could see that my water flow was insufficient.  I tried a smaller injector which improved the range at which suction was created, but it still was not enough to get the ozone I needed in the water.  The Mazzei performance chart indicated that the well pump moved about 5 gallons per minute. When the pressure switch on the well pump sensed low water pressure, it turns the pump on.  The Venturi worked at first, but as the pressure in the system increased to the point when the pressure switch turned the pump off, the Venturi quit working.  So how can I increase the time ozone is injected?

I had an idea.  If the Venturi was working better at low pressures, then adjust the pressure switch so that it allowed the water pressure to get lower before it turned on.  I adjusted the switch to turn on at 35 psi instead of 45 and the Venturi was able to pull in ozone until it reached 47 psi.  The pump continued to pump till the switch turned it off at 75 psi.  This water mixed with the ozonated water in the tank.  Dissolved ozone measurements indicated adequate concentrations under ideal conditions.  But sometimes water use keeps the pump running at a pressure where no ozone is being injected.  That simply was not going to work.  I left for the day, and got a call the next morning from the customer.  The water pressure in the house was not going to work for three teenage girls getting ready for school in the morning.

The well pump was not creating enough flow to make the system work.  I needed to add a pump to increase flow.  Flow from the well cannot be increased, so the pump would circulate 15 gpm through a loop.   I turned the pressure switch back up and installed a pump wired to turn on when the well pump turned on.   I plumbed to pull water at a T from the bottom of the tank where the pressure switch and bladder tank were hooked up and push it through a T where the well water was coming in.

Again I turned on the pump breaker switch.  My new pump began to circulate water, balance barometer indicated some suction, ozone generator turned on, …. but only for a while.  The system was not working any better than before!  And a new problem surfaced: the well pump took longer to turn off because the new pump inlet reduced the pressure at the pressure switch.

After pondering this problem and looking at other system diagrams, it seemed to me that the Venturi should come before the water inlet from the well pump. More plumbing changes. Multiple Venturi size tests. But I still not able to get the flow and pressure differential I needed when the well pump was running. I noticed that if I turned the breaker off for the well pump, I was able to get good suction with just the circulation pump running.

A Venturi will work only if you can maintain a pressure differential between the inlet and the outlet.  Even with the well pump adding into the circulation pump outlet, the system configuration was not creating the flow needed through the Venturi.  If I understand it correctly, the well pump seemed to be fighting against the circulation pump.

It would be better if the well pump was feeding water into the system just before the circulation pump.  This would level the pressure “playing field” across the loop before the circulation pump pulled well water and some water from the mixing tank through the Venturi.  Again I flipped the well pump breaker switch.  This time the balance barometer showed a healthy level of suction.  The ozone generator kicked on.  As the pressure increased, the suction reduced but it stayed on until the well pump turned off.  This is what I was looking for!  Now it was working.

A Gallon of 3ppm Aqueous Ozone for Sale

Ozonated water, bleach, and hydrogen peroxide are three oxidizing agents useful for disinfection, odor control, color removal, water treatment, food preparation, and more. Bleach and hydrogen peroxide are common, low cost household items, but you will never find a gallon of ozonated water in the store even though it has many superior qualities. Equipment can be purchased to make a gallon of aqueous ozone, but how does the price compare to hydrogen peroxide or bleach? Let’s figure it out.

Oxidizers pack stored up molecular energy that breaks apart odor and color molecules. The energy is released on contact and physically disables or destroys microorganisms and viruses. Bleach, a combination of chlorine and oxygen, is valuable because it is stable and will oxidize over a long length of time. Hydrogen Peroxide, a water molecule with one extra oxygen atom, can also be stored and its oxidizing power applied when needed. Ozone molecules combining 3 atoms of oxygen are dissolved in water to produce ozonated water,, better known as aqueous ozone. The ozone immediately reacts with any contaminants in the water and breaks down to oxygen over a matter of minutes.

Oxidizers are very useful for solving everyday problems. You can find a bottle of 3% hydrogen peroxide in most households, and barrels of 35-50% peroxide in many different industries. Even more common is a gallon of bleach. The power and value of oxygen is well-known, and the convenience of having this power in a jug of hydrogen peroxide or bleach is very attractive. A gallon of aqueous ozone also contains this oxidating power, and its uses are diverse and growing. You will not find a gallon of ozonated water for sale because it has a shelf life of minutes. It is highly reactive and therefore quickly dissipates back to oxygen within a matter of minutes. The only way to get this powerful tool is to make it as needed with electricity.

Before discussing the equipment needed to ozonate water, we will explore some of the ways it can be used. Ozone dissolved in water has been used for over 100 years in large scale industrial settings, but a growing number of people are discovering the value of ozonated water in smaller applications. The demand for environmentally friendly and healthy solutions to problems is driving the demand for ozonated water and the technology to provide it.

Bacteria and mold is an age-old problem for food preparation and storage. Aqueous ozone provides an attractive alternative to chemicals that may alter taste or lead to health problems. Aqueous ozone has the power to destroy bacteria as well as improve taste, smell, and appearance of many foods. A gallon of aqueous ozone can
1) Rinse a bushel of cranberries to prevent a 20% loss due to mold
2) Extend the shelf life of 20 pounds of fresh fish
3) Make 10 gallons of freshwater safe to drink
4) Provide a Log 3 reduction in bacteria count on three butchered chickens
5) Disinfect a wine carboy
6) Disinfect food preparation equipment
7) Disinfect cow udders before or after milking

Ozone will enhance the value of polluted water by helping to remove many contaminants. Ozone dissolved into a gallon of polluted water has the power to
1) Remove discoloration
2) Oxidize dissolved iron for filtration
3) Clean aquaculture water
4) Lower the chemical cost of cooling tower operation
5) Wash clothes in cold water.
6) Treat a pool or spa.
7) Remove pathogens and add oxygen for hydroponics.

This list only scratches the surface of possibilities. Many of the uses people have found for hydrogen peroxide can be accomplished with aqueous ozone. While the convenience of stored oxidative power is attractive, there are also advantages to having this power on tap. An ozone water system makes this possible, and the value may be surprising.

This brings me back to the question: how much would you pay for a gallon of ozonated water? Let’s suppose you were willing to pay somewhere between the $0.02 for bleach or $3 for the hydrogen peroxide option … $1 a gallon. Our OXS-10 ozonated water system can produce about 10 gallons of 3 ppm ozonated water per minute. At that rate, it would make 600 gallons an hour, or a value of $14,000 per day. Even at $0.05 a gallon, an OXS-10 system generates a value of $700 per day.

If you did not need that much aqueous ozone, and just wanted a few gallons to rinse produce for your family or wash clothes, some different options are available. The simplest way to prepare some ozonated water is to use a small ozone generator and a bubble stone. Bubbling ozone in a gallon of water using a small ozone generator can dissolve some ozone in water, but it is not very efficient and is difficult to attain 2 ppm without dealing with significant off-gas. Even so, many people do this and are happy with the results.

Electrolytic devices are under development and available to provide up to 2 ppm aqueous ozone from a handheld spray bottle or from a kitchen tap. They generate ozone directly from water by running an electric current to special electrodes in the water. Electrolytic devices are convenient, but over time the electrodes get fouled with minerals and ozone output levels decline. Regular cleaning with a vinegar solution restores their function.

The SB-100 spray bottle is a convenient way to apply a spray of ozonated water over a kitchen counter or for rinsing produce. When used with clean water and given a regular vinegar rinse, the spray bottle will provide 1000-2000 hours of use. It sprays 1/2 a cup of ozonated water a minute at up to 2ppm concentration. That would be 30 cups an hour or about 2 gallons an hour. Over its expected life, it will provide up to 4000 gallons of ozonated water. With a price tag of $499, the cost of a gallon of ozonated water from the convenience of a spray bottle comes to between $0.12 and $0.25.

Another option is a small battery powered pen-sized device – the O-Pen which provides a convenient way to disinfect a 16-ounce glass of water in one minute. This is equivalent to 960 ounces or 7.5 gallons per hour. Over its expected life, it has the capacity to ozonate 7500 to 15,000 gallons of water. The O-pen can be purchased for $150, so the cost of a gallon of ozonated water comes to $0.02 to $0.01 per gallon.

The OZO-Pod is capable of bringing a gallon of water up to 2-3ppm within a minute. At $189, this device is capable of providing a gallon of ozonated water at less than a penny a gallon.

Electrolytic devices provide a very simple and convenient means for making small amounts of ozonated water. They are prone, however, to fouling problems if the water quality is poor. The most reliable, long-term equipment for producing larger amounts of ozonated water consists of a high concentration ozone generator supplied with dry air or an oxygen concentrator and an injection venturi with off-gas tank. Most hot tubs have a small ozone generator with a venturi built into the circulation plumbing. A variety of options using this technology are available for home laundry applications as well.

The WT-4 ozone water system can produce 300 gallons of 1-2 ppm water for pennies a gallon over its expected life. Our industrial line of ozone water systems (OST series, OXS series, ISX series) are capable of providing much higher concentrations of dissolved ozone if needed. The ISX system can provide up to 500 gallons per minute. We also provide service and larger equipment for municipal water treatment plants.

At a penny a gallon, making 500 gallons of aqueous ozone a minute generates a value of at least $300 an hour and breaks a million dollars in value after only 5 months of operation. Hydrogen peroxide and Clorox have their place, but ozonated water is a very competitive option to supplement or replace these oxidants.

In summary, the base price for a gallon of aqueous ozone is anywhere between $0.01 and $0.25 depending on the type of equipment used. In general, a lower initial cost of small equipment will mean a larger price per gallon because it makes less ozone and doesn’t last as long. Top quality industrial equipment will be expensive, but will make large quantities of aqueous ozone and last a long time.

The actual cost of a gallon of aqueous ozone needs to include the cost of a gallon of potable water and maintenance costs for the machine. The average price for a gallon of potable water is $0.01. Even if the spray bottle at $0.25 a gallon only lasted half its expected life, you could have gallons of aqueous ozone for under $1 a gallon. Maintenance and time spent on larger machines would at the most double the cost of aqueous ozone and still be only pennies a gallon.

We can make a better price comparison to hydrogen peroxide and bleach if we dilute the typical 3% peroxide to 1%. This would have similar oxidizing power to 3ppm aqueous ozone. We can make a 100 ppm bleach solution to get an equivalent for bleach. Doing this we have the following table for comparison:

1 Gallon of 1% hydrogen peroxide $3

1 Gallon of 3 ppm ozonated water – $0.03 – $0.25

1 Gallon of 100ppm bleach solution – $0.02

The Terribly Fresh Smell of Ozone

Our noses have snuffed up the fresh smell after a thunderstorm, clean laundry, and well-aerated water ever since creation; but we were not aware that a simple combination of three oxygen atoms was responsible for these delightful odors until Christian Friedrich Schönbein zeroed in on this fact in the later 1800’s. The peculiar odor was noted by the Dutch scientist Van Muram in 1801 when he ran his electrostatic generators. He called it “the smell of electricity.” Schönbein’s experiments with electrolysis also generated some ozone. Although this odor was not the focus of his studies, he could not resist investigating the source of this smell. He felt close enough to finding this substance to give it a name. For this he turned to the language of the insightful and descriptive Greeks.

Scanning through the various forms of “smell” in a good Greek dictionary for a suitable name, he came across the verb form ὄζω which sounds like “odzo” and translates “I smell” as in, “I smell the rain.” The root word in Greek for smell is ” ὀδ” from which the English word “odor” is derived. Typically you read that the word “ozone” comes from the infinitive form ὄζειν “to smell,” but I would like to suggest he was attracted to the genitive form “ὄζων” which sounds most like the German “ozon” and the English “ozone.” The genitive form is used to express the idea of source, and is used in Greek texts to mean “that from which the smell comes.”

“Ozone.” The word fit well. The ancient Greek poet Homer, reciting his epic poem “The Iliad” about 1000 years before Christ said,

“As an oak falls headlong when uprooted by the lightning flash of God,
And there is the terrible ozone of brimstone –
No man can help being dismayed if he is standing near it
For a thunderbolt is a very awful thing –
Even so did Hector fall to earth and bite the dust.
Homer, The Illiad, Book XIV

Here Homer connects the odor of ozone with lightning and its awful power. Instead of translating the Greek word “ὄζων” as “smell”, I have simply transliterated the sound of the Greek word directly to “ozone.” Schönbein’s name for this substance was an excellent choice, having a few thousand years of historical precedent for naming this important molecule.

A variety of careful observations about the circumstances of ozone production and its effect on other substances brought Schonbein closer to understanding the precise composition of ozone. Eventually in 1865 another man, Jacques-Louis Soret, determined the precise formula for ozone as O3. Experiments with ozone exposed some of the harmful effects of high ozone levels to plant and animal health, but also led to the realization that ozone could be used to disinfect polluted water. It became clear that with proper use, ozone could be a powerful tool for healthy living. The fresh, invigorating, clean smell of a tiny pinch of ozone is our hint to ozone’s helpful qualities.

A little dose of bright sunshine on our skin is good for the body. It is healthy and we are attracted to it, but too much can burn and cause harm. So it is with ozone. Just like fire or electricity, its power must be respected and put to precise and careful use. We need a gentle flow of electrons through our nervous system to think and direct our bodies, but need protection from the power of electricity in the world around us.

How much is too much? At about the time the smell of ozone becomes distinctive, it is time to be aware of its source and the potential for dangerous levels of ozone. With an increase in concentration, it turns quickly to a pungent suffocating smell. At that point it is time to limit breathing exposure to avoid oxidation of sensitive lung tissue. Only a good quality ozone sensor that is up to date with calibration will give accurate measurements of ozone levels. OSHA requires that workers not be exposed to ozone levels over 0.1 ppm ozone over the course of 8 hours.

Ozone as the “smell of electricity” could also be described as “the smell of energy.” Ozone is oxygen that has been infused with a tremendous amount of energy. When that energy is released, it causes physical damage to small sensitive things like bacteria, viruses, and sensitive lung tissue. The fresh smell of ozone after a thunderstorm is our reminder that big powerful things are happening to bring refreshing rain. A hint of ozone smell in a water bottling plant can make you confident that the water is free of harmful pathogens.

Ozone is a very valuable form of oxidizing energy with countless uses. Dissolved in water, ozone retains its power to disinfect, but does not come into contact with the sensitive tissue of your lungs. It is safe to handle ozonated water provided any ozone off-gassing is limited or safely removed. Dissolved ozone is like electricity in a shielded wire where it is safe and useful. Those who build and operate machines that harness the power of ozone must understand and respect the power of ozone as well as the rules and regulations that have been put in place for the safe use of ozone.

How Much Ozone Do I Need to Destroy Bacteria and Viruses?

How much ozone do I need to destroy pathogens? The question is similar to asking “how much heat do I need to cook an egg?” This question is more easily answered when put in terms of time and temperature. Five minutes in boiling water can produce a softboiled egg. Ten minutes in boiling water will produce a hardboiled egg. The ozone question can be answered in a similar way: About three seconds of exposure in 0.5 ppm ozonated water can destroy 99% of E.coli bacteria. Six seconds of exposure in 0.5 ppm ozonated water can destroy 99.99%. Time and ozone concentration are the two main factors needed to how much ozone is needed.

If the ozone concentration is lower, it takes longer to destroy the bacteria. In a similar way, it takes longer to cook meat when the temperature is lower. A higher temperature cooks faster, but can also have undesirable side effects. Higher concentrations of ozone destroy pathogens more quickly, but also can have undesirable side effects. When cooking a piece of meat, the goal is to reach a particular internal temperature. In the disinfection industry, the goal is a particular Contact Time or CT value. The CT value is often given in units of mg/min -1 which is equivalent to ppm x time in minutes.

The CT disinfection value is a number that tells you when a particular type of pathogen has been “cooked” or inactivated to the desired level. The numbers come from a CT value chart. For example, the chart here gives a set of CT values for inactivating cryptosporidium. The CT value needed to inactivate 99% (2 Log) of the cryptosporidium at 15 degrees Celsius is 12. If my ozone concentration in the water is 2ppm, then I need to maintain that level of ozone in the water for 6 minutes. Ozone concentration (2ppm) x Time (6 min) = 12.

Another chart gives the CT values for inactivating 99% of a variety of different pathogens at 5 degrees Celsius with four different kinds of disinfectants. E.coli bacteria have a very low CT value of 0.02 with ozone. A 0.5 ppm concentration of ozone requires only 0.04 minutes (2.4 seconds) of contact time to inactivate 99% of E.coli. Chlorine is also an oxidant, but it is not as strong an oxidant as ozone. The chart shows the CT values of three different forms of chlorine. All of them have a higher CT value and therefore require a higher concentration or a longer contact time for the same level of disinfection.

When you start looking at CT charts, you will notice that water temperature has a significant impact on CT values. In cold water, ozone does not react as quickly as it does in warmer water. Keep in mind, however, that the ozone level in warmer water declines more quickly as it oxidizes things. As the ozonated water moves through a pipe or reaction chamber, it may begin at 4 ppm, and end at 2 ppm. (see charts at end of post)

Temperature is not the only factor to consider. Minerals or other organic compounds in the water will be oxidized by the ozone and reduce the concentration. Contact time may also vary depending on water demand. A CT value table provides a solid starting point, but all the other factors that affect ozone and limit contact of ozone with a particular organism must be considered when determining how much ozone will be needed.

A five gallon bucket and a stopwatch will give a fairly good measurement of your water flow in gallons per minute. Ozonated water flowing at 5 gallons per minute through a 10 gallon tank will provide about 2 minutes of contact time. Dissolved ozone test kits are a low cost method of measuring the ozone levels in water. Dissolved ozone sensors that provide a continuous digital reading of dissolved ozone levels are much more expensive. Measuring the Oxidation Reduction Potential (ORP) is a cheaper option, but does not give a direct ppm measurement. However, some sampling with a test kit can provide a fairly accurate correlation chart (see blog post) of ORP and dissolved ozone levels in your water.

Related blog posts and links to products.

Dissolved ozone test kits

Low Level Ambient Ozone Effectively Neutralizes Coronavirus

It is no surprise that ozone will neutralize coronavirus. Ozone is well known to be a powerful disinfectant. It is especially effective with small pathogens such as viruses and bacteria. Some of the more recent studies have demonstrated that coronavirus can thrive in the air in the form of aerosols breathed from people. Recent research has demonstrated that low levels of ozone gas effectively neutralizes coronavirus.

Ozone is a simple high-energy molecule of three oxygen atoms and will irritate sensitive tissue such as our lungs when ozone concentrations exceed 0.1 parts per million. The good news is that coronavirus is much more sensitive to ozone than our lungs are. “Scientists at Fujita Health University told a news conference they had proven that ozone gas in concentrations of 0.05 to 0.1 parts per million (ppm), levels considered harmless to humans, could kill the virus.”


The important details are the ozone level and the contact time. Coronavirus exposed to ozone concentrations of 0.1 ppm for 10 hours reduced the potency of the virus 90%. Ozone is not a magic bullet, but it is a valuable tool in our arsenal for fighting the virus. It is a safe, comfortable, and effective tool that can provide secondary benefits. The ultraviolet rays of the sun and lightning naturally produce low levels of cleansing ozone. Well-controlled equipment is already available to bring some of the fresh outdoors into our living and working spaces to stand side by side with others in the battle against viruses.

Oxidation Technologies has worked for years to produce safe and effective ozone generating equipment. We specialize in equipment controls to precisely maintain specified ozone levels for commercial applications. We have the equipment and expertise to maintain safe levels of ambient ozone that will greatly reduce the ability of coronavirus to thrive. We would be happy to assist in your efforts to get employees back into the workplace.

Surface Sanitation with Ozone: A Non-toxic, Residue-free, and Effective Alternative

Each year almost a half a million people in the world die because of bacteria, viruses, and other pathogens in the food they eat.  https://www.businessinsider.com/annual-food-poisoning-deaths-2015-12  The United States Center for Disease Control (CDC) estimates that 1 in 6 Americans get sick each year from contaminated food, and 6000 die.  In addition to the suffering and death caused by the contaminated food we eat, the economic impact of food contamination is in the billions of dollars each year.  Ozone has proven to be an environmentally friendly, safe, and effective sanitizing agent for every stage of food processing.

The diligent efforts of government agencies and food production facilities to implement procedures and policies serve to limit and control the potential for contaminated food, but people continue to get sick and multi-state outbreaks of food borne disease continue to increase.  New antibiotic resistant strains of bacteria and more centralized food production are only a couple of the factors that may be contributing to the new challenges we face.  Of all the strategies to manage food contamination, an enduring and key part of preventing sickness and death from food contamination is careful surface sanitation.  


A clean surface is the first step for food safety. https://www.cdc.gov/foodsafety/keep-food-safe.html  As our food travels from the field to our table, it comes into contact with equipment that is constantly repopulated with disease causing pathogens from incoming food, food handling equipment, water, air and employees.  Unless careful, repeated sanitation practices are maintained, pathogens thrive and multiply on the surfaces of food processing equipment, contaminating food as at passes through.  https://www.who.int/foodsafety/areas_work/foodborne-diseases/ferginfographics.pdf?ua=1

Food processing facilities maintain rigorous sanitation procedures to combat the threat of contamination.  Physical scrubbing and washing down of surfaces is followed up with sanitation methods that kill the bacteria and microscopic pathogens that remain.  Heat and chemical sanitizers are frequently used to eliminate these pathogens, but have their limitations and negative consequences.  Ozone is a safe and effective alternative to destroy these pathogens and keep surfaces free of dangerous pathogens. 

A growing number of food processing plants are using ozone to eliminate bacteria, viruses and other harmful contaminants on food.  When ozone is dissolved in water, the ozonated water serves as a powerful disinfectant that is safe and effective not only on equipment and surfaces, but when applied directly to food products.  As the ozone destroys harmful pathogens, it turns back into oxygen and safely disperses, leaving no residue.    

Recent FDA approval for using ozone directly on food and improvements in ozone equipment have opened the door for the use of ozone to combat food born illness.  For many years, food processing plants have been restricted to using heat, pressure, and chemical methods of disinfection, even though ozone has been used since the early 1900’s in water treatment plants for disinfection.  In August 2, 2000, the Electric Power Research Institute (ERPI) petitioned the FDA to approve of using ozone directly on food to reduce the level of harmful pathogenic microorganisms.  In addition to providing a wealth of technical information about ozone, the 380 page petition cites over 80 studies of ozone and food sanitation conducted over the past 60 years. https://ioa-pag.org/resources/Documents/Applications/Food%20Additive%20Petition.pdf  The following year, the FDA granted GRAS (Generally Recognized as Safe) status to ozone as a food additive. https://www.federalregister.gov/documents/2001/06/26/01-15963/secondary-direct-food-additives-permitted-in-food-for-human-consumption  Since then, ozone use has increased dramatically in food processing.

Chlorine has been a common sanitizer in the food processing industry.  It is a simple and convenient sanitizing solution.  The convenience of Chlorine comes with the problem of residual chemicals in waste water and a building of resistance to Chlorine of E.Coli and Giardia microorganisms.  Chlorine and other chemicals can also react with metals and wood equipment used in the food and beverage industry causing damage and flavor alterations.  Concerns about water contamination with residual chemicals, food quality, and equipment maintenance make ozone an attractive option for sanitation.  https://www3.epa.gov/npdes/pubs/ozon.pdf 

Ozone is a gas that is made from oxygen, and turns back into oxygen as it breaks down.  Ozone is responsible for the fresh smell generated in lightning storms.  Two oxygen atoms bound together form the stabile oxygen molecule.  Passing oxygen through an intense electrical field breaks this oxygen bond, and energy is stored in the three-atom arrangement called ozone.  The sanitizing power comes from the energy stored in the ozone.  Ozone gas is a highly energized form of oxygen composed of three oxygen atoms instead of the more stabile combination of two atoms.  This gas readily dissolves into water to provide a powerful disinfecting solution.   The energy is released as contaminants are broken down, and the oxygen atoms return to the lower energy form of O2.

 Unlike a chemical sanitizer that can be stored in a barrel and added to water when needed, ozone cannot be generated in a factory, concentrated, and stored in a bottle or barrel to be sold to the end user.  The ozone would all turn back to oxygen before it could be used.  Instead, ozone is generated with electricity on site when needed and injected into a water stream to be used immediately.  As ozone makes contact with contaminants, the energy is released, destroying the contaminants and returning to the two-atom low energy state of oxygen. 

A reliable industrial ozone water injection system will often pay for itself after a year of reduced chemical costs.  Chemical disinfectants may be needed to provide some residual protection, but the bulk of the disinfection can be achieved with ozone. The system in general does not take any more space than the totes of chemicals it can replace.  The electrical and preventative maintenance costs are well worth the improvements in food quality and zero chemical footprint in wastewater. 

A little bit of ozone goes a long way in disinfection power.  A small ozone generator using a couple hundred watts of power is capable of making enough ozone to turn 20 gallons per minute of water into a 2 ppm dissolved ozone sanitizing solution similar to using 200 ppm Chlorine in water.   Ozone decomposes rapidly, but in exchange, it provides a more rapid rate of disinfection.  The precise ozone concentration and contact time will vary with the particular application and pathogen. 

How to Dismember Corona Virus with Ozone

Given the mountain of evidence that ozone is a quick and effective destroyer of viruses and bacteria, why is there so much hesitation to champion ozone as a key weapon against the spread of Covid 19? The EPA has a list of 478 different products and 30 active ingredients that officially kill the Covid virus, but ozone is nowhere to be found in the list. The closest thing to ozone that is on the list is hydrogen peroxide. Have all these products actually been applied to the virus and proven to destroy or inactivate it? How can you tell if a virus is dead or inactive? Given what we are gradually learning about the virus, how it spreads, and how it infects our bodies, how effective are these disinfectants in preventing infection?

Dr. Chedly Tizaoui, a professor of chemical engineering at Swansee University has taken a rather novel approach in an attempt to answer some of these questions. Instead of conducting statistical analysis of thousands of people or trying to count dead viruses after applying a particular disinfectant, Dr. Tizaoui has applied molecular modeling to evaluate the effect of ozone on the molecular structures the virus. He shares his results in the International Ozone Association research journal “Ozone: Science and Engineering” https://www.tandfonline.com/doi/pdf/10.1080/01919512.2020.1795614?needAccess=true

Molecular modeling is an especially useful tool for studying viruses because viruses are so small they can’t be seen with a standard light microscope. Their shape and structures are defined on a molecular level, so understanding the types of molecules making up their structure allows us to make an accurate model. The model not only evaluates the shape and function of corona virus anatomy, but it also evaluates the bonds holding these molecules together. Understanding the relationships between these molecules and how they function together to make the Corona Virus so sucessful provides important insight in the weaknesses and vulnerabilities of the virus.

We may not yet know all the complex interactions of the virus with people, or exactly how the virus infects, but we do have a pretty clear understanding of the molecular structure of the virus. It is also clear that the unique shape and structure of the molecular structures on the outer shell play a key role in the success of the virus. Molecular modeling is a tool that helps us see how this structure is altered when a molecule like ozone comes into contact with it.

Ozone is like a molecular hand grenade in the virus world and has the power to change the shape of the virus’s “arms” and disable them. Various kinds of molecules behave and react in predictable ways making it possible to use molecular modeling to study what happens when something like ozone molecules interacts with the structures on a virus.

Ozone is an exciting molecule to model because it packs a lot of energy. The molecule is very sensitive and quick to unload its energy on nearby molecules. It has a very positive 100 year track record for effectively destroying viruses and bacteria. The water treatment industry has grown to appreciate the value of ozone for destroying pathogens in water. The food industry is also learning how to harness its power for sanitation and shelf life extension. Ozone has also been used extensively in medical treatment, but faces an uphill battle against the pharmaceutical and chemical industries.

After applying the science of molecular modeling to Corona Virus anatomy and ozone, Dr. Tizaoui concludes, “The results show that ozone is able to attack the proteins and lipids of the virus’s spikes and envelope, particularly the amino acids tryptophan, methionine and cysteine, and the fatty acids,varachidonic acid, linoleic acid, and oleic acid. Ozone also attacks the N-glycopeptides of the spike protein subunits 1 and 2, though at lower reactivity. Disruption of the structure of SARS-CoV-2 could inactivate the virus, suggesting that ozone could be an effective oxidant against COVID-19 virus.”

Thank you, Dr. Tizaoui, for sharing this research. Now it’s our job to safely get the ozone where it needs to be to do its work.

Measuring Dissolved Ozone in Chloronated Water

How to dilute sample to extend test range

Is there a way to measure dissolved ozone (0.5 to 3.0 ppm) in water with a high chlorine level. Yes, there is a way to to this.

First, be sure to use the Indigo Method.

The Indigo Method

“References: Bader H. and J. Hoigné, “Determination of Ozone in Water by the Indigo Method,” Water Research Vol. 15, pp. 449-456, 1981. APHA Standard Methods, 23rd ed., Method 4500-03 B-1997.

With the indigo method, indigo trisulfonate dye immediately reacts with ozone. The color of the blue dye decreases in intensity in proportion to the amount of ozone present in the sample. The test reagent is formulated with malonic acid to prevent interference from up to at least 10 ppm chlorine. Results are expressed as ppm (mg/L) O3.The CHEMetrics Indigo Ozone Vacu-vials® Kit employs an innovative “self-zeroing” feature to eliminate the need to generate a reagent blank. Each Vacu-vials® ampoule is measured before and after being snapped in sample. The change in color intensity, measured in absorbance, between reagent in the unsnapped and snapped ampoule is used to determine the ozone concentration of the sample.”

The indigo test kit can be purchased at the Oxidation Technologies web store. Indigo test kit.

The I-2022 Dissolved Ozone Meter is designed for accurately and quickly measuring ozone in water levels from 0 – 0.75 ppm. This device uses the Indigo Method for testing. This method is based on the colorization of dye by ozone, where the loss of color is directly proportional to the ozone concentration. The results are then displayed on the monitor in ppm (mg/L) of ozone present.

This device has LED display for precise and accurate readout and is easy to use. Once the I-2022 has been purchased the cost per test is only $1.02.

Next, use the dilute method to measure higher concentrations of ozone.

The Indigo snap method test kits will measure up to 0.75 so a dilute procedure can be used to derive an accurate measurement. The video uses the K-7404 kit which used the DPT method, but the principle can be applied to the Indigo kit as well.

Feel free to contact Oxidation Technolgies with any ozone questions.

Ozone for Iron Removal

Thought I would share my quarterly maintenance report for an ozone iron removal system serving a hog farrowing operation. Iron in the water had been causing high maintenance costs on the power washing equipment used to maintain a sanitary environment. We sized an ozone well water treatment system to remove the measured iron levels at a rate of 20 gallons per minute. The system injects ozone with a venturi, circulates it through a contact tank, and filters the oxidized iron with two sand filters. It has been running for a year and a half now and continues to provide excellent iron removal results. The picture shows two water filters, grey one with clay silt from the well water prior to entering the system. The red one is a post system filter to remove any iron the sand filters missed. I used the Chemetrics iron test kit we sell to verify results. The clear ampule reflects a post-filtration reading of 0.2 ppm total iron. The medium colored ones reflect a pre-treatment sample of 1 ppm iron. The dark-colored one was a test of the backflush water indicating what the sand filters are removing. Overall, the system is operating very well. I changed filters and check valves, measured system performance, and prepared a report for the customer. This summer the demand will be higher on the system, so I will try to get there a little before the next scheduled visit. Ozone can provide excellent results when properly applied and maintained. We are happy to provide quarterly maintenance to keep your ozone system operating at peak performance. Give us a call at 515 635-5854. We’d be happy to provide service for any ozone equipment on the market.