Good and Evil of Ozone

The ozone hole is slowly healing

The Coronavirus pandemic has sparked an exponential increase in interest in ozone as a disinfectant. The phones at Oxidation Technologies have been ringing non-stop with people looking for answers and looking for help with their grand ideas for ozone as a silver coronavirus bullet. Our ozone specialists have been working hard to provide accurate information for those looking for answers. Ozone has been a powerful tool for over a hundred years, but misinformation is dangerous in a climate of desperation and hype. Our goal throughout this health crisis has been to educate our callers about safe and unsafe uses of ozone, effective and ineffective applications of ozone, and the facts and false claims people make about ozone.

If there is so much interest in ozone as a powerful and chemical-free disinfectant, why do we read so much about ozone as a very bad and deadly pollutant? For example, the American Lung Association says “Ozone (also called smog) is one of the most dangerous and widespread pollutants in the U.S.”  On the other hand, the Food and Drug Administration (FDA) approved the use of ozone as an antimicrobial agent for the treatment, storage and processing of foods in gas and aqueous phases.” For years, now, we have recognized the value of an atmospheric layer of ozone that shields “living things from too much ultraviolet radiation from the sun.” Ozone sterilization of water has made the bottled water industry possible providing billions of bottles of safe drinking water. The answer to this paradox is not difficult or mysterious, but does require some ozone education. We hope you take some time to explore the wealth of ozone information on our website.

You’ll Know You’re Getting Chemical Free Home Water Disinfection When …

Ozone has been used to disinfect water for over 100 years. Many water treatment plants throughout the world not only use ozone to disinfect water, but also remove organic compounds and improve taste and smell. Ozone is an attractive alternative to chemical treatment because it is very effective and does not introduce any new chemicals to the water you use. The drawback has been a high initial cost and equipment maintenance. Advances in technology have brought ozone within the reach of the average home owner, and small scale reliable ozone generating equipment has stood the test of time. Our ozone water treatment (WT) system is simple to operate and monitor to ensure that it is working properly to provide safe water. Here are five routine, simple, and quick checks of your ozone WT system to maintain your peace of mind.

You will know your water’s staying clean when …

1) The desiccant air dryer feels warm.

Put your hand near the top of the air dryer. Does it feel warm? If it is cold, something is not right. The air dryer contains two cylinders of desiccant material. It is the same stuff you find in little packets sometimes placed in the packaging of sensitive electronic equipment. This material absorbs moisture from the air. Eventually it becomes saturated with water and no longer absorbs moisture. The water is removed by heating the desiccant material. The desiccant air dryer is designed to cycle back and forth between two cylinders filled with desiccant material. When air is flowing through one to remove the moisture, the other is being heated to drive off the moisture. If the outside of the box feels warm, this is a good sign that all is well.

2) The moisture indicator is blue.

The moisture indicator provides additional assurance that your ozone equipment is getting dry air. This little viewer contains crystals that change color in the presence of moisture. When it is blue, you can be sure the air feeding your ozone generator is dry. If it is not blue, it could mean that the dryer is not working properly, the crystals have been contaminated in some way, or the crystals need to be replaced. Don’t become alarmed right away. The dryer requires a good six hours of uninterrupted operation to stabilize. If the location is excessively warm or humid, the dryer will not perform well.

If you continue to suspect that the air dryer is not performing as it should after a number of checks over the course of a few days, try to determine what has failed. If the dryer feels warm but the moisture indicator is not blue, it may be that the moisture indicator is contaminated. New moisture indicators are available from our store. It is also possible that the desiccant material has been contaminated or worn out. In that case, you will need one of our desiccant refill kits. If the air dryer feels cold, check the power connections. We also sell replacement heater tubes that contain the desiccant. If you are unable to verify that the air dryer is working, it may be time for a new dryer.

The only part of the treatment system that is active 24/7 is the desiccant air dryer. All the other components wait until the well pump turns on.

3) The little silver ball in the flowmeter jumps up and hovers when the well pump turns on. (Newer models have a digital reading of air flow)

The flowmeter is a simple device telling us how much gas is flowing through the system. Air is pulled through the air dryer and ozone generator by suction produced by the black plastic venturi. Suction is created by the flow of water through the venturi. When the well pump turns on, water rushes through a narrow passage in the venturi. With sufficient flow, the water pressure differential between the input and output of the venturi creates air suction. Air flows through the tubing as it is pulled into the venturi. The little silver ball is lifted by this gas flow giving a visual indication that air is flowing through the system.

If no air flow is created when the water pump turns on, remove the ozone tube connected to the black venturi. Place your finger over the hole to see if suction is created. As long as the pump is running, the venturi should create air suction. If there is no suction, remove the check valve that is threaded directly to the venturi. Clear out any rust or mineral deposits. If the pump stops, water will squirt from this port, so try to open enough faucets to keep the pump running. If you are unsuccessful with getting air suction from the venturi, it could mean that the well pump is not pumping enough water through the venturi to create suction, or the venturi has worn out.

If you do have air suction at the venturi, but still no air flow indicated on your flowmeter, it may be that a check valve needs to be replaced or something else is blocking the flow. The source of blockage needs to be found and cleared before ozone generator will operate. The ozone generator turns on when it senses a sufficient flow of air. Most ozone generators will have a blue light indicating that the ozone generator is running.

4) You can smell ozone from the off-gas vent

But can you be sure that that sufficient ozone is being generated to disinfect your water? When your system is operating properly, left-over ozone that does not get dissolved into the water is vented from the top of your contact tank. If you remove the tubing from the off-gas vent, you should smell ozone when the system is running. It might take a little while for enough ozone gas to build up for venting, but when it accumulates at the top of the tank, it will be vented, often in short spurts.

5) Testing your water for dissolved ozone levels.

Ozone is a more powerful disinfectant than Chlorine. It destroys, inactivates, and prevents growth of bacteria and viruses with very low levels of dissolved ozone in water. As little as .3 ppm dissolved ozone for contact time of 5 minutes provides a 5 log (100,000 bacteria reduced to 1, 99.999% reduction) reduction of most bacteria and viruses. Contaminants are exposed to much higher levels of ozone when it passes through the venturi. By the time the water leaves the contact tank, any contaminants have been in contact with ozone long enough for most of them to be destroyed. The ozone has done its job and very little is left in the water that is distributed to your home. Enough will be left over to prevent growth. As little as 0.01 ppm will prevent growth. These low levels of ozone leaving your contact tank can be measured with our low cost K-7404 dissolved ozone test kit. You don’t want much ozone left in your water. Too much ozone left over in the water can lead to irritating ozone off-gas at the point of use.

Journey to the Center of a DBD Ozone Generating Plasma Cell.


Photo by Devansh.sharma – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=36462262

A Not-So-Lazy River Circuit Analogy

Our journey to the center of an ozone generating plasma cell begins with a ride around a not-so-lazy river. Perhaps you’ve enjoyed floating in a raft around a lazy river at a hotel or water park. Picture these rafts as electrons flowing through a circuit. Moving magnetic fields are pushing electrons through the fluid media of metal atoms. They follow the circular paths of circuits like rafts floating around and around the lazy river ride. A pump continually pushes the water along.

Unlike the continuous flow in one direction of direct current (DC), alternating current continuously reverses the flow of electrons. Imagine the lazy river model constantly changing direction. The electrons first flow one way, slow, reverse, and rush the other way. The electric supply to your home goes through 60 cycles per second. Our lazy river model begins to defy imagination at this rate of change. You can think of electrons as virtually weightless, unlike all the water and rafts in a lazy river. Electrons are quite capable of reversing direction very quickly.

Energy Transfer
The flow of electrons through a wire might be apparent from the glow of a light bulb. As electrons squeeze through a resistive part of the circuit, the wire heats up transferring energy to heat and light. Other things are happening outside the wire. Hold a compass near a wire in which current is flowing, and the needle is pulled away from North. Whenever an electric current flows, a magnetic field develops around the wire. Stop the flow, and the field collapses.

Wrap this conductor into a coil, and the magnetic field is intensified. Add an iron core, and a magnet is born. A continuous flow supports a useful magnetic field, capable of pushing the rotor of a motor or the lever of a switch. Again we notice a transfer of energy, this time from electric current flow to some mechanical motion. Energy transfer doesn’t stop there.

Energy transfer is reversed in a magnetic field when the electric current stops. When current stops or reverses, the magnetic field collapses. The collapsing magnetic field gives electrons a push in the coiled conductor. This phenomena opens up the possibility of generating a flow of electrons in a second circuit that is isolated from the first circuit. It also introduces radio waves. Imagine a second lazy river next to yours. It doesn’t have a pump, so the water is still. But imagine an invisible force generated by the flowing of the first river pushing the water along in the second. Such a transfer of energy happens with the flow of electrons and is essential to ozone production within a plasma cell.

A Dam in the River: The Plasma Cell Heart

A dam in the lazy river brings the rafts to a halt, but build two Olympic sized pools on either side of the dam. Now the river continues to flow awhile even with a dam because it takes time to fill the pool. Depending on the strength of the pump, the water flows for a while as one pool gets a little deeper while the other is drawn down. If you can pump one pool much deeper than the other, a significant stress builds on the dam. Our lazy river could get exciting if the dam were to burst. We are getting closer to the center of a plasma cell.

In your mind you need to convert the Olympic sized swimming pools in our lazy river circuit to large flat pieces of metal. In the electron world, the dam between these two plates is an insulator, a material that prevents the flow of electrons. Electrons pile up on one side while they are drawn down on the other side. Electrons are the negative charge. Pulling electrons away leaves one side with deficiency of electrons: a positive charge. If the insulator were breached, a powerful surge of electrons would create a dramatic spark. It would be equivalent to the deep swimming pool emptying to the shallow one in milliseconds.

It is here at the “dam” where we discover the center of a plasma cell. When the distance between the two electrically charged plates is made smaller, the electrostatic forces between them grow exponentially. In other words, a thinner dam makes a more powerful electrostatic field. But a thin dam is also weaker and more susceptible to failure. The goal is a material that is strong and a good electrical insulator. Ceramic and quartz serve well for this purpose. But without some oxygen present in this high electrical pressure environment, we only have a capacitor and no ozone production.

We need to introduce one more element: a thin layer of oxygen as part of the “electron dam.” We can think of the dam as a sandwich of two insulators with a very thin slice of oxygen between them. When oxygen is exposed to the tremendous electrostatic forces found within this space between highly charged surfaces, the oxygen molecules are pulled apart and re-combine in highly energized forms. I would like to zoom in for a closer look at this sliver of space.

A Peak Inside the World Between Dielectric Barriers

Photographs of this space between the two insulators reveals what appears to be a mini, but intense electrical storm. We are used to thinking about lightning bolts jumping from one charged conductor to another, but in this electrostatic microcosm, the mini “bolts of lightning” are jumping from the surface of one insulator to the surface of the second insulator. In the presence of the strong electric field, the molecules within the insulator become polarized. This means that the electrons are pulled by the positive electrode toward one end of the molecule that make up the insulator. Even though electrons are unable to flow through the insulator, the polarization sets up “pools” of electrons on the surface. We call the insulating material used in in this application a “dielectric.” The type of ozone generator we are entering here is a dielectric barrier discharge (DBD) generator.

Exactly what is happening in this high electrical pressure world between dielectric barriers has been and continues to be a topic of considerable research and study. Already around 1897, John Townsend discovered that the strong electric field in the oxygen space between dielectrics initiates electron avalanches. A free electron among the oxygen atoms accelerates very quickly because it is attracted to the positively charged plate (anode). When it reaches a high enough velocity and collides with an oxygen molecule, it knocks off another electron, turning the molecule into a positively charged ion. This ion begins to move in the opposite direction toward the negatively charged plate (cathode) while the two electrons further accelerate toward the anode and collide with more oxygen molecules.  As the growing electron cloud races toward the anode, it leaves a trail of positively charged ions in its wake.

This trail of ions and free electrons is conductive, and allows for a discharge of electric current through the oxygen. The discharge is the flow of electrons that has gathered on the surface of the dielectric towards the positive charge on the other side of the oxygen gap. It is this discharge of energy that breaks the oxygen molecule bonds releasing free oxygen atoms. Some re-combine with single atoms, and others combine with pairs to form highly energized ozone molecules made of three oxygen atoms. The world here at the center of an ozone generator is a stormy one swarming with surges of electrons.

DBD: A Specialized Form of Corona Discharge

The discharge is similar to a spark, but not nearly as hot. It does not result in a discharge of the electrodes. Only small areas of the inside surface of the dielectric discharge with each electron avalanche. The strong electric field induces a secondary, high voltage mini-circuit within the oxygen gap. Thousands of these discharges can be repeated as long as the voltage supplied to the anode and cathode continues to increase.

The power supply for an ozone generator alternates this electric field thousands of time each second. When the pressure (voltage) rises through the threshold that sets off electron avalanches, the discharge storm erupts. Since the electric field changes thousands of times each second, the oxygen gap experiences thousands of storms each second. The optimal frequency and voltage depends on the gap size and oxygen pressure. The electronics controlling the voltage need to be tuned to match the particular dielectric arrangement for optimal ozone production.

The benefits of setting off thousands of mini discharges in a space between insulators instead of simply allowing a spark to ark between the positive and negative electrodes are the following: 1) an arc generates so much heat that it melts most materials. Such an arc is useful for welding or plasma torches, but would destroy an ozone generator. 2) Ozone production is minimal with an arc. Most of the energy is converted to heat and the heat destroys ozone. 3) Producing many small discharges from dielectric surfaces within a strong electrical field stays cooler and yields more ozone.

This form of ozone generation is called “Dielectric Barrier Discharge” (DBD). DBD belongs to a category of corona discharge. Corona discharge was observed by ancient sailors on the masts of their ships as a flare of luminous plasma at the tips of the mast and other pointed parts of their ship when the atmosphere is highly charged. The phenomenon occurs when strong electrostatic forces concentrate at sharp points and break down air to form plasma. You can observe this phenomena with an electrostatic generator in a dark room. Many of the small ozone generators sold for home use rely on a form of corona discharge from sharp points. Higher quantities of high concentration ozone used in commercial applications often use DBD type ozone generators.

Ozone can also be produced with ultraviolet light and radiation bombardment. The ozone layer which protects earth from harmful radiation is produced by ultraviolet light with a wavelength less than 200 nm. Ultraviolet light between about 200 and 300 nm destroys ozone. The ozone layer is maintained with a balance of ozone generation and destruction with ultraviolet light. Ozone can be created in water with electrolysis. Passing an electric current through water breaks the water molecules into hydrogen and oxygen. Using specific electrodes results in oxygen combining to form ozone.

Here at Oxidation Technologies we do not build DBD plasma cells, but we rely on companies who continue to research and build quality generators for a wide range of applications. We specialize in integrating the right ozone generators into specific applications. Dissolving ozone into water requires ozone generators that make higher concentrations of ozone. Many applications can utilize low pressure or even slight vacuum to minimize the danger of ozone leaks. Sometimes controlling precise levels of low ozone concentrations can best be attained with an ultraviolet ozone generator. Whatever your application, we have the expertise to integrate the right ozone generator to your process.

Ozone: Science & Engineering  The Journal of the International Ozone Association  Volume 41, 2019 – Issue 1Ozone Synthesis and Decomposition in Oxygen-Fed Pulsed DBD System: Effect of Ozone Concentration, Power Density, and Residence Time Sławomir Jodzis &Tobiasz Barczyński From https://www.tandfonline.com/doi/abs/10.1080/01919512.2018.1506317>

IOP Science publication: Dielectric barrier discharges: progress on plasma sources and on the understanding of regimes and single filaments From <https://iopscience.iop.org/article/10.1088/1361-6595/aa6426>

Journal of Physics B: Atomic and Molecular Physics  Electron impact dissociation in oxygen B Eliasson and U Kogelschatz Journal of Physics B: Atomic and Molecular PhysicsVolume 19Number 8

From <https://iopscience.iop.org/article/10.1088/0022-3700/19/8/018>

Free Use article from IOP Science:  https://www.researchgate.net/publication/230926959_Ozone_Synthesis_From_Oxygen_in_Dielectric_Barrier_Discharges/link/56ddd42608aedf2bf0c86b95/download

Plasma Chemistry and Plasma Processing, Vol. 23, No. 1, March 2003 ( 2003) Inûited Reûiew Dielectric-barrier Discharges: Their History, Discharge Physics, and Industrial Applications Ulrich Kogelschatz1 Receiûed April 5, 2002; reûised May 7, 2002 https://www3.nd.edu/~sst/teaching/AME60637/reading/2003_PCPP_Kogelschatz_dbd_review.pdf

Very clear and graphic explanation https://www.plasma-school.org/files/lectures/2016/Guaitella16.pdf

https://iopscience.iop.org/journal/0963-0252/page/Foundations-of-low-temperature-plasmas-and-their-applications

Impact of Ozone on Pharmaceuticals and Personal Care Products

Every day, pharmaceutical companies around the world produce tons of products that people use to enhance their quality of life. This realm of products has been lumped into a category called “Pharmaceuticals & Personal Care Products,” (PPCPs). These products and drugs do not disappear, but are found increasingly in the water being discharged from wastewater treatment plants. The impact that this cocktail of chemicals has on the animals and people dependent on this water is not fully understood, but the evidence is clear that it is not good.

Ozone is a powerful oxidant capable of breaking troublesome molecules. What impact does ozone have on PPCPs? A recent laboratory study published in the engineering journal of the International Ozone Association (IOA) exposed water containing thirty seven different PPCPs to investigate the degradability of these chemicals.

Eight of the thirty five were very quickly degraded to or below their limit of detection with a dissolved ozone dose of 1ppm within 5 minutes. Five more were degraded with a dissolved ozone dose of 2ppm within 5 minutes. Five more required at least 10 minutes of retention time at 2 ppm.

The other half of the thirty five required more time and a higher dose of ozone. Three of them, (DEET, Ketoprophen, and Primidone) did not degrade below their limit of detection even when exposed to 9ppm of dissolved ozone for 15 minutes.

Ozone clearly has a significant role to play with PPCP cleanup. Further study is sure to discover ways to optimize the process and make it more effective. Oxidation Technologies  specializes in integrating ozone into the specific process of diverse customers. We continue to pursue a better understanding of ozone use in a variety of applications.

Source:

N. Evelin Paucar, Ilho Kim, Hiroaki Tanaka & Chikashi Sato (2019) Ozonetreatment process for the removal of pharmaceuticals and personal care products in wastewater, Ozone: Science & Engineering, 41:1, 3-16, DOI: 10.1080/01919512.2018.1482456

 

Control Dangerous Bacteria in Water with Low Levels of Dissolved Ozone

Legionnaires’ disease is a bacterial pneumonia caused by breathing mist from water containing the bacteria. The bacteria thrive in the warm water found in whirlpool spas, cooling towers, fountains, humidifiers, produce misters, etc. Symptoms of Legionnaires’ disease include high fever, a cough, and sometimes muscle aches and headaches.

The rate of reported cases has increased over 5 fold since 2000, and deadly outbreaks continue today unabated. The reason or reasons behind this increase are unclear at this point, but ozone has proven to be effective at controlling the bacteria in water. Whether the bacteria are flourishing within a 100 gallon fountain or a 1000 ton cooling tower, the engineers at Oxidation Technologies will maintain will provide the precise dose of ozone needed for safe water.

Ozone that is safely dissolved into water has a tremendous disinfectant power and simply turns back into oxygen after expending its energy. As little as 0.01 ppm (1 part ozone to 100 million parts water) prevents the growth of these bacteria. We provide cost effective equipment and long term service to ensure safe and effective use of ozone for bacteria control.

The equipment needed to dissolve low levels of ozone into water can be very cost effective and sustainable for many water systems. A home well-water system uses one of the smallest ozone generators we sell to dissolve enough ozone when the well pump runs to disinfect all the water needed in a typical home. As a general rule of thumb for industrial cooling towers, five grams of ozone per hour is needed for every 100 tons of tower cooling capacity.

The 50 g/h ozone generator needed to supply a 1000 ton cooling tower will also require an oxygen concentrator, venturi, ORP controller, and sometimes a booster pump. The oxygen concentrator and controller comes in a complete package with our OXG systems. The following study conducted by Mazzei reports a one year payback for ozone use due to lower chemical and cleaning costs.

We also provide the convenience of a quarterly preventative maintenance plan to make sure the system continues to perform at peak efficiency and avoid costly repairs due to neglected maintenance. We often work with an independent water company that provides routine testing for the customer to make sure water quality remains good and inform us of any problems.

Check out our website for more information and give us a call with any questions.  Oxidation TechnologiesPhone: 515-635-5854
Toll Free: 844-398-9579
Tech Info E-mail: info@oxidationtech.com
Sales E-mail: sales@oxidationtech.com

A Home Remedy for Ailing Oxygen Concentrators

An oxygen concentrator is a wonderful machine … when it works. Attempts to diagnose and repair a your concentrator when it fails can be very frustrating. But understanding just a few principles of operation may turn frustration to success.

Principle #1 Remember your sand box.


If you have ever played with a sieve in a sandbox, you already understand the science behind an oxygen concentrator. The air we breathe contains about 78% Nitrogen and 21% Oxygen. The other 1% is composed of a few other gasses. An oxygen concentrator is a sieve that lets Oxygen molecules through and holds back the Nitrogen molecules.

So you need to picture some poor quality sand with about 80% pea gravel mixed in. It’s nice and dry, so when you scoop some up in your sieve and shake it a bit over a bucket, you end up with some nice, beach quality sand and a sieve that’s still got a lot of pea gravel in it. Dump out the gravel into another bucket and do the same thing over again. Slowly but surely you fill your sand bucket with some nice sand. This is like the tank of oxygen you accumulate with an oxygen concentrator. The pea gravel dump pile is the Nitrogen that hisses out of the concentrator muffler. Take the muffler off, and you can get a better feel of the process.

Principle #2 – Respect the destructive power of moisture

Now, you might recall that when you get some wet sand in your sieve, the process doesn’t work so well anymore. You might need to shake it more and everything starts to clog up. Moisture causes lots of problems for an oxygen concentrator as well. Once it starts to condense in the sieve material, the sieve begins to break down. It would be like your sandbox sieve falling apart or getting rusty so that either everything just goes straight through or it gets completely plugged and nothing goes through. The sieve material in an oxygen concentrator is in the form of little clay pellets that are treated with zeolite. This material does a great job sorting out the Nitrogen from the Oxygen, but is very vulnerable to moisture.

If the sieve material has been exposed to moisture and has begun to break down, you will begin to see signs of this process with dust that starts blowing out of the exhaust mufflers. It is best to take care of the problem as soon as possible, because the dusting will only lead to more problems. It will begin to disrupt the valve operation and may even totally clog up the mufflers to the point where the Nitrogen can’t exhaust anymore. Chances are, by this time the sieve material is ruined and is not filtering out the Nitrogen anymore.

What to do. Unfortunately, if your sieve material is breaking down, your concentrator sieve beds will need to be rebuilt. The sieve bed needs to be opened up, old material dumped, and new sieve material put in. Sieve beds are typically in the form of two aluminum tubes with some screens and a spring to hold the sieve material in place. These need to be carefully cleaned, inspected for damage, and carefully put back together so that it is sealed up tight. If you’re not up for the challenge of rebuilding the sieve bed, you can send the beds in to us for a re-build.

Principle #3 Valves need to operate flawlessly.


Rebuilt sieve beds may not be the whole solution. There is a good chance that the dust from degraded sieve material has found its way to the valve set. The valves are your arms working the sieve in the sandbox: dig up some sand, hold it over the sand bucket, dump out the gravel into the gravel pile, do it all over again and again and again. If you’re sloppy, you’re going to get gravel in your sand.

In an oxygen concentrator, two sieves are at work together. When one is sifting, it is also at the same time helping to clean out all the Nitrogen being exhausted by the other sieve bed. The valves direct a certain quantity of air for a certain time into the sieve. Too much air, and it is like the sieve overflows and Nitrogen spills into your oxygen, diluting it. If the Nitrogen isn’t dumped properly, the next cycle is ineffective and disrupts the rhythm.

The valves need to open to let compressed air into the sieve for a certain time. Oxygen flows out the other side through an orifice and a check valve. As the air valve closes, it opens a second port to release the Nitrogen trapped in the sieve back into the surrounding air. A second valve lets compressed air into the second sieve. As it fills, some of the oxygen leaving the other end helps force the remaining Nitrogen out of the first sieve.

The valves are typically a spindle that slides back and forth to direct the gas flow. A solenoid pushes the spindle back and forth. When electricity flows through the coil of wire in the solenoid, the magnetic field generated pushes a plunger to move the spindle. The spindle needs to move freely. Dust or contaminants can interfere with its movement so that the air is not precisely measured or timed properly. A careful cleaning of the valve often will fix a sticky valve, but sometimes even when it seems to be operating smoothly, only a new set brings the precision needed for proper operation.

Principle #4 Check valves and orifices may seem insignificant, but they’re not.

What looks like little connectors for oxygen tubing are actually precision parts that work together with the air valves to direct the Oxygen and Nitrogen flow. Orifices are precisely sized holes that limit the flow of Oxygen. In a concentrator, they are often used to allow a limited amount of Oxygen to push out any remaining Nitrogen left after exhausting from the de-pressurized sieve. If it gets plugged, Nitrogen stays in the sieve and ends up contaminating your oxygen supply. The check valves prevent any excess oxygen from flowing back into the sieve. Make sure the oxygen hoses are clear of debris, you can blow air through the orifices, and the check valves work. You should be able to blow through one way, but not the other. They need to be oriented so that the oxygen flows to the oxygen tank and not back.

Principle #5 More O2 flow is not better

A simple thing to overlook when trying to figure out when the O2 purity isn’t what it should be is excessive oxygen flow. Bring back to mind the sieve in the sandbox. The sieve is only so big. It will only hold so much sand and pea gravel. If you exceed the capacity, extra material is going to fall over the sides and not go through the sieve. Try operating your concentrator at a flow rate that is lower than the maximum rating. If you get good oxygen purity at a low flow rate, but it starts to fall off as you approach its rating, you might have some oxygen leaks. An oxygen leak won’t be measured by your flowmeter. Use some soaping water to look for leaks and fix them.

We sell and service most brands of industrial oxygen concentrators, stock parts, and do all we can to keep oxygen concentrators healthy. We also sell and rent oxygen meters to determine the oxygen purity of a system. A diet of clean, dry air is proven to greatly extend their life. They are designed to handle a limited amount of moisture, but it is risky. Continuous use, just like regular exercise, will also extend life. Startup on a humid day will be hard on them. Hot humid air from the compressor is liable to condense in a cooler sieve and begin the cycle of damage. If the suggested remedies do not solve your concentrator problems, feel free to give us a call.  Oxidation Tech Phone number

Precise Ozone Control for Recirculating Aquaculture Systems (RAS)

The delicate balance of natural systems of the oceans provides an abundance of food for the world. The current rate of harvest, however, is degrading this rich resource. Inland farming of ocean fish is becoming an attractive alternative. Precise ozone control is a key component for replicating an ocean environment for inland farming of ocean fish.

Ozone provides excellent disinfection, enhances the filtration process, and increases the overall efficiency of recirculating aquaculture systems (RAS). Ozone is one of the most powerful disinfectants available. It accelerates the natural processes of breaking down toxins and filtration. It is made of oxygen, and decomposes back to oxygen or oxides when its work is finished.

The latest edition of “Ozone News: The Newsletter of the International Ozone Association”
Vol. 47 no. 4 published an article giving details of this technology:

“Foam Fractionation and Ozone in Modern Aquaculture Systems: Valuable Tools for Clear Water Production and Farm Management

Abstract
Recirculating aquaculture systems (RAS) for farming finfish is a technology that offers the necessary biosecurity and water quality control, as well as waste management. Modern closed recirculating systems can operate far away from the natural water source and a water consumption of less than 1% of the system volume per day. High-tech systems such as the oceanloop technology (neomar.de) allow the land-based production of fish species of high commercial interest and value, close to the consumer. This technology [10] represents the cutting edge of science and technology. The discharge of nutrients and organic matter can be well controlled. The technology is environmentally sound and supports the sustainability of aquatic food production. Key words: Aquaculture, Foam Fractionation, Ozone

Conclusions The re-use of water is inevitable in modern aquaculture production systems. The use of biological water treatments, combined with a foam fractionation process, enhanced with ozone are crucial. Farm managers can profit from clear water production in terms of increasing both, mean stocking density without affecting fish welfare, and survival rate due to an optimization of water quality.”

Oxidation Technologies brings precision control to customized ozone production.

Water Reclamation – IOA 2019

Behind the scenes at the Atlanta Aquarium. Filtration and ozone equipment in the background.

Ozone use to control odor and pollutants in large water treatment plants is well documented and growing. In addition to disinfection benefits, the ozone breaks down pollutants so that they are better removed with bacteria and filtration. The research and testing for these large plants provides a rich resource for developing a variety of small scale water treatment systems for applications like aquariums, car-washes, building water reclamation, and water condensate treatment.

The IOA convention this year provided an opportunity to visit the Atlanta Aquarium. This aquarium is the largest in the western hemisphere and is home to four whale sharks and over 100,000 other aquatic residents. The filtration system recycles the 10 million gallon capacity in approximately 1.5 hours. The filtration system incorporates ozone to maintain water clarity and disease control. The stunning display of aquatic life and continual maintenance of its health speaks well for the power of ozone.

Many of the presentations at the 2019 IOA convention presented research and studies relating to water treatment plants that treat over 500 million gallons of water per day. The aquarium was a great example of this process on a smaller scale. One of the presenters shared a project of implementing ozone to treat water-reuse for a train-car wash facility. Ozone was used to address a concern of biological contaminants picked up by the vehicles and entering the wash water. Ozone eliminated the danger of pathogens making the operators sick.

Ozone works well by itself for destroying pathogens, but needs help with filtration methods to clean up the left-over scraps. Many studies conducted for large waste water facilities demonstrate that ozone is often most effective for odor and pollutant removal when combined with filtering and/or hydrogen peroxide. Ozone alone will break down many pollutants, but some compounds require more energy. Hydrogen peroxide in the presence of ozone generates powerful oxidizing molecules
Hydroxyl Radical (OH-) which are even more effective. Ozone often breaks pollutants down to the point where they are more easily digested by bacteria in a biologically active filter (BAF). The ozone causes some molecules such as dissolved iron to coagulate so they are larger and can be filtered out.

Our team at Oxidation Technologies has worked with various food and recycling industries looking for ways to reclaim water for further process use. We are dedicated to understanding your process so that we can provide the equipment and resources you need and stay within your budget. We offer rental systems  that can be used for experimentation before committing to a permanent system designed to fit your application.

Iron In Your Water? Ozone Can Help.

Rusty stains. A sure sign of iron in your water.

High iron content in water often results in disagreeable metallic taste and unappealing color in cooked vegetables. Although not a health threat, iron bacteria thrive in this water and contribute to biofilm and discoloration. Dissolved iron eventually leads to ugly stains on fixtures and clogged pipes. Removing iron from your water supply is well worth the investment.

The most common piece of water treatment equipment for homeowners is the water softener. Your water softener is designed to remove calcium from the water. It may remove some of the iron, but iron is prone to stick to the resin bed and is difficult to flush out.

An iron filter is a much more effective method for removing iron. There are a variety of filter systems, but they all follow the two step process of oxidizing the iron and then filtering it out. Iron that is dissolved in water can’t be filtered out until it is oxidized or made into larger rust particles that are large enough to be filtered.

Simply aerating water containing dissolved iron will begin the oxidation process needed for filtration. This method is simple, but can introduce some new problems such as increased bacteria growth. It is also slower and difficult to control effectively.  

Some compact home iron filtration devices contain media which accelerates the oxidization process and also serves as a filter to remove the oxidized particles. Like a water softener, these systems require periodic back flushing and eventually require chemical regeneration. The effectiveness of these systems is dependent on PH levels and do not disinfect the water. Iron bacteria can still cause problems by leaving ugly stains on water fixtures.

Adding a chemical feed pump to introduce chlorine, calcium hypochlorite or potassium permanganate increases the oxidation. These systems are able to remove higher iron levels and also serve to disinfect the water. The disadvantage is the ongoing cost of dangerous chemicals.

Ozone is one of the most powerful oxidants. Using ozone to oxidize iron before filtration not only quickly oxidizes all the iron, it oxidizes magnesium and Sulfur compounds as well. Ozone also provides complete disinfection and leaves no chemical residue.  “Ozone can be very effective at treating well water for residential, commercial, or agricultural applications.” Ozone is powerful and requires robust, well-designed equipment to harness its power. Our CWS Ozone Water Filtration System will provide years of service.

Ozone has been used for water treatment for over a hundred hears. It is used extensively for bottled water treatment because it is an effective disinfectant and improves taste and color. Oxidation Technologies specializes in harnessing the power of ozone for a variety of water treatment needs.

Making Sense of Ozone Measurements

How much ozone is a particular machine making?

How concentrated is the ozone?

CONCENTRATION

One useful way to measure ozone concentration is to state how many parts of ozone are present per million parts of gas (normally air.) We can smell ozone when it is present in the air in as low as .01 parts per million (10 parts per billion). At .1 ppm levels in ambient air, ozone becomes uncomfortable. Industrial ozone generators can produce ozone in concentrations well over 100,000 parts per million. Usually these larger concentrations are expressed in % by weight. 100,000 ppm could be written as 100,000/1,000,000 which is 10/100 or 10%. Because the weight of an ozone molecule is heavier than the other gas molecules making up air, the actual measurement is 13.7 %wt. Parts per million is useful for many applications, but sometimes it is handy to use parts per billion for very low concentrations. The general principle is to reduce the number of zeros when communicating this information. We do the same thing when measuring distance with millimeters or kilometers etc. A good starting point to get a feel for ozone concentration is to become familiar with ppm and %wt. We provide definitions for other common units and links for conversions and calculators at our calculations page.

QUANTITY

A second dimension of ozone measurement is the actual quantity of ozone being produced or used. The production of smaller generators is measured in grams per hour. The production of the largest generators is measured in pounds per day. 1 lb/day ozone = 18.89 g/hr ozone. The smallest ozone generators we sell generate less than a half of a gram per hour. That would be about a hundredth of a pound per day which is an awkward figure to use. “Grams per hour” happens to be practical for describing the output of lower production machines. The larger ones we sell generate 1000 grams per hour or 50 pounds per day. Pounds per day happens to be practical for larger machines. A drinking water treatment plant in Texas uses up to 42,900 pounds of ozone per day (over 200 tons). One lightning storm can generate over 200 tons of ozone.

FLOW RATE

A third dimension of measurement for any gas application is flow rate. When generating ozone, flow rate will affect the ozone concentration. With a given ozone production rate (for example, 200 grams per hour), lower flow rates will result in higher ozone concentrations. Higher flow rates will result in lower concentrations. One useful calculator helps determine the amount of ozone needed to supply a particular concentration at a particular flow rate.  For example, if you need a concentration of 5% by weight and have an oxygen flow of 10 LPM, you will need a generator capable of 43 grams per hour. If the flow doubles to 20 LPM, the concentration is cut in half.

People working with municipal water treatment get used to working with larger units such as pounds per day and high ozone concentrations. People working with sanitation equipment and other mid-scale applications get used to thinking in terms of grams per hour and the whole spectrum of ozone concentration measurements. Those involved in small household applications and generators are more familiar with milligrams per hour and low concentrations. Our system integration experts need to be familiar with the whole spectrum of measurements. Familiarity and precision in application grows with years and diversity of experience. Our online calculator provides a powerful tool for an efficient and effective integration of ozone into your application.

Oxidation Technologies provides equipment, engineering expertise, and service to a wide range of applications and ozone demands. Our service requires flexibility in thinking and a familiarity with the full spectrum of ozone concentrations. We build ozone systems to integrate into your existing industrial process. Every situation has a multitude of variables that will affect the performance.

Give us a call. We’d love to help you harness the power of ozone for your application.  515-635-5854