Compare the Venturi Injector to the Bubble Diffuser

Compare the Mazzei Venturi Injector to the fine pore Bubble Diffuser to dissolve ozone into water

The two most common methods of dissolving ozone into water is the venturi injector and the bubble diffusion method. Each has it’s own advantages and disadvantages and applications where it might be best used.

History

Early ozone applications used large basins or tanks and bubble diffusers as the primary method to dissolve ozone into water. Ceramic diffusers were readily available and tanks or basins offered a simple and effective method to dissolve ozone into water. As ozone applications evolved and became more popular additional methods of dissolving ozone into water were investigated. In 1983 the Mazzei Injector company started producing special ozone compatible venturi Injectors specifically for the ozone markets. This brought the venturi injector into the mainstream ozone market from the smallest to the largest water flows and applications.

While the venturi injector can offer improved mass transfer efficiencies and smaller footprints there is still a place for the simple bubble diffuser yet today.

Advantages vs Disadvantages

Fundamentals of ozone solubility:

Bubble Diffuser Advantages: Low cost No moving parts Easy to setup Low energy – does not require water pumps or elevated water pressures Simple, reliable operation long-term  Venturi Injector Advantages: Extremely efficient ozone transfer Great option for pressurized water More ozone dissolved into water = less ozone off-gassing = safer environment Easier to contain ozone gas and maintain a safe environment due to ozone off-gassing Smaller tanks and overall footprint of the system can be achieved
Disadvantages: Ideal tank/basin depth for effective ozone transfer is 18-24 feet deep Ideal tank depths are not realistic in most applications causing this to be a less efficient transfer method. Diffusers can become plugged and may require periodic replacement Difficult to use in pressurized water flowsDisadvantages: Typically requires more energy than other options due to required pressure differential across venturi injector Requires flowing, pressurized water Greater risk of water backing up into the ozone generator as the water is pressurized Venturi can plug or become obstructed in contaminated water
  • – Lower temperatures increase the solubility rate of ozone gas into liquid
  • – Higher pressures increase the solubility rate of ozone gas into liquid
  • – Higher ozone gas concentrations increase the solubility rate of ozone gas into liquid
Ozone bubbled into tank with bubble diffuser Ozone gas dissolved into a tank with a fine pore bubble diffuserDissolve ozone into water with venturi injector Ozone gas dissolved into a tank with a pump and venturi
Sealed ozone tank with venturi injector Ozone gas dissolved into water in a sealed, pressurized system with a venturi injector.  Capable of dissolving ozone into pressurized water inline while safely capturing all undissolved ozone gas.

Design considerations in favor of Bubble Diffusers

  • Existing tanks or contact basins on-site whose height favors the bubble diffuser should be considered
  • Off-gassed ozone is more challenging to capture and handle with diffusers. If tanks are outdoors, or have proper venting in place already a diffuser may be a simple solution
  • Clean water applications where low dissolved ozone levels are required are well suited for bubble diffusers as high levels of ozone transfer are not needed.  

Examples of applications where Bubble diffusers may have an advantage:

  • RO water holding tanks
  • Bottled water applications
  • Well water applications with outdoor water holding tanks
  • Drinking water applications with large tanks or basins in place

Design considerations in favor of Venturi Injectors

  • If higher dissolved ozone levels are required a venturi injector is ideal as high transfer efficiency will be required to achieve these dissolved ozone levels
  • Varying water flow rates
  • Applications where pressurized water will have ozone gas added

Examples of applications where Venturi Injectors may have an advantage:

  • Sanitation applications where water is the carrier of ozone and high dissolved ozone levels are required
  • New construction water treatment applications where tanks are not already in place
  • Applications where footprint is a concern and space is limited
  • Well water applications where ozone will be added to water under pressure

Find Original article HERE

Ozone for Rainwater Re-use

Great video below to show the use of ozone in rainwater re-use applications. However, the first half of the video provides great general info about ozone that is helpful to anyone wanting to learn a bit more about ozone.

Also, the info about ozone mixing is relevant to many ozone applications and industries. If you have a moment and are interested in ozone applications, give this video your attention.

SM-50 Discontinued – Why the OEM-3 is a great alternative

The SM-50 Ozone Controller has recently been discontinued. However, we are offering the OEM-3 Ozone Controller which is a great alternative. Below we will list some of the similarities and differences between the two ozone controllers to show you why the OEM-3 is a solid alternative. Please note – some of the data below also refers to the OEM-1 and OEM-2, more information on those products are also available on our website, but when it comes to a replacement for the SM-50, we highly recommend you check out the OEM-3.

The OEM-3 and SM-50 are both Original Equipment Manufactures (OEMs) Ozone Sensors that are designed with state of the art sensor technology that can be integrated into your own equipment.  OEM Sensors are a great addition to any Ozone System to help ensure any ozone leaks are detected and the Ozone Generation system is shut off.  The OEM sensors can be integrated into your system to control your Ozone Generation system and turn it off/on based on your preset levels. Below we will lay out the benefits and differences between the EcoSensors OEM-3 and the Aeroqual SM-50 OEM Ozone Sensors.

OEM-3

OEM-3 Ozone Controller

Abilities/Features:

  • 3 range options: 0-0.1ppm, 0-1ppm, 0-10ppm of ozone
  • Can control Ozone Generators and alarms based on an adjustable ozone concentration set point
  • Sensor replacement (SM-1) is simply plug-n-play
  • Pre-calibrated sensors
  • OEM-3 is a 12/24 VDC powered board that offers a 4-20mA output
  • Sensors can be located up to 25ft (8meters) away from the board using an extension cable
  • Base Board incorporates power supply, final signal processing, set-point controls and output relay
  • HMOS (Heated metal oxide semiconductor) Sensor

SM-50

SM50 Sensor & Board

Abilities/Features:

  • 3 range options: 0-0.15ppm, 0-0.5ppm, 0-10ppm of ozone
  • Analog voltage
  • Relay and status indicators
  • Optional RS232 or RS485
  • Factory calibrated and ready to use
  • Preloaded firmware that optimizes measurements and enhance data output
  • User set points to trigger alarm
  • GSS (Gas Sensitive Semiconductor) Sensor
  • Optional use of: 2 analog voltages inputs and 2 GPIO which can connect a temp/RH sensor
  • Accuracy +/-10%

Disadvantages:

  • Complete board needs to be replaced when sensor goes bad.
  • Currently discontinued

Main differences:

Why Use OEM Sensors?

Ozone Sensors should be used in EVERY Ozone Generator to ensure safety for anyone that might be exposed to unsafe levels of ozone.  OSHA has regulations for ozone and proper safety precautions that should be set in place, such as an ozone sensor to shut of Ozone Generator when unsafe levels are detected, is one of them.  If regulations are not followed, it could cost your company a lot of money.  See this story that talks about the fines from OSHA due to worker safety levels.

More information on the OEM-3 can be found on our website.

OEM-3 – https://www.oxidationtech.com/oem-3.html

Mazzei Injector Co.: A 40-year overnight success story

One of the most important components of most ozone water systems is the venturi injector. The ozone industry has used Mazzei venturi’s since the beginning with the great support of Angelo Mazzei and his team at Mazzei Injector Company. I ran across this great article about Angelo Mazzei written from the perspective of a completely different industry. It’s worth the read.

Complete article HERE

Congratulate Angelo Mazzei on his 2021 Irrigation Association Industry Achievement Award and he’s likely to shift the attention to the support of his family and the employees of Mazzei Injector Company. Ask him about his 20 patents in fluid processing and he’ll probably tell you the story of how he ground away on the lathe in his garage to help solve a fertilizer mixing challenge on his uncle’s farm near Bakersfield, Calif.

With the improvements he made on venturi injectors in his garage workshop, Angelo Mazzei has changed the irrigation industry—and wastewater treatment, drinking water plants, even the wine industry—but he’s always quick to humbly point out that he’s a son of California’s Central Valley, a local boy with an engineer’s mind, a driving persistence, and a wife who encouraged him to follow his inventive instincts.

When the California Aqueduct piped water to his uncle’s 10,000-acre vegetable farm where Angelo Mazzei worked, it created vast opportunities, but also posed a challenge to irrigators who were accustomed to injecting fertilizer into reservoir water on the suction side of their booster pumps. The State Water Project delivered water at 20 to 40 pounds per square inch (psi)—enough pressure for sprinklers, but not enough for old-style venturi injectors to draw in fertilizer.

Drawing on an engineering class he’d taken at California State University, Fresno, Mazzei went to work in his garage to improve Giovanni Venturi’s brilliant technology. In Venturi’s design, fluid or gas is compressed in an intake cone, then allowed to expand in an outlet cone; the change in velocity creates a vacuum that pulls in other liquid or gas through a suction port.https://2c93de8848c61f9ca96d37d635eb2931.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

Mazzei adjusted the geometry and positions of the cones and suction port, dramatically reducing the amount of pressure differential required to inject fertilizer and mix it into irrigation water, making it possible for his uncle—and farmers around the world—to tap the power of the water itself.

A little challenge

“It was a little challenge to convince the patent attorney that a 181-year-old invention had any improvements,” Mazzei laughs. “I was really persistent because I thought I had stumbled on something that would be really beneficial for the irrigation industry.”

Beneficial indeed. Angelo and Mary Mazzei established their company in 1978, and sales of their venturi injectors took off as California farmers adopted drip irrigation. Mazzei soon turned to figuring out how to use his injectors to help a vegetable company aerate its wastewater lagoon to reduce odors. Over the years, his initial 1978 patent was joined by 19 more, representing advances in injection, mixing and automation in irrigation and other liquid systems.

Today, high-efficiency drip is common not only in the field, but also the foundation of indoor farming systems like greenhouses and vertical farms. Precision management of irrigation resources, process water and wastewater—as well as other inputs—will be even more vital to irrigated farms around the world, and automation is an increasingly important strategy as farmers struggle with tight labor markets. Think SCADA for farming.

More than fertilizer

Mazzei injectors have found applications well beyond fertilizer injection. Tiny Mazzei injectors treat spa water with ozone to protect bathers from pathogens. Massive ones inject air, oxygen or ozone for drinking water and wastewater treatment at huge municipal plants. And the sizes in between are used for injecting and mixing ozone for sanitizing and advanced oxidation processes in industrial wastewater treatment processes.

One of the most exciting recent applications of Mazzei injectors has been the development of the company’s AirJection system, which injects air into subsurface drip irrigation lines to aerate the root zone. Researchers around the world have demonstrated yield and quality improvements in crops ranging from melons to tomatoes to cotton.

And an innovative research team from Fresno State (Mazzei’s alma mater) and Memorial University of Newfoundland found that aeration significantly improves the balance of microbe genera in the soil, paving the way for improved nitrogen use efficiency.

Lifelong support of learning

Throughout his career, Angelo Mazzei has supported education. Dedicated to developing future agriculture leaders, he has contributed equipment, funds and technical expertise to California State University, Bakersfield, where he also serves on the foundation board; California Polytechnic University, San Luis Obispo; and University of California, Davis.

Mazzei has maintained particularly close ties to Fresno State, the school that helped him set the course for a life of innovation. There, he has been deeply involved in projects with faculty and students, and helped establish the university’s International Center for Water Technology.

Mazzei’s commitment to education extends to the lifelong learning provided by industry associations. He has been a member of the board of directors of the Kern Agricultural Foundation and an active participant in the Irrigation Association, California Agricultural Irrigation Association and the International Ozone Association.

Continued growth

Mazzei’s interest in lifelong learning drives his company, too. His daughter Celia Cobar joined the business, and as director of research and development, introduced computational fluid dynamics (CFD) modeling to the company’s capabilities. Mazzei Injector Company has developed dramatically since Angelo Mazzei’s days of experimenting in his garage. The ability to model the flow of liquids and gas inside the system and out has allowed Mazzei and his team to fine-tune injectors, pipeline flash reactors, gas separators, mass transfer nozzles and more.https://2c93de8848c61f9ca96d37d635eb2931.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

But despite all his technical and business achievements, Angelo Mazzei brings the conversation back to the people around him.

“My most proud accomplishment is building a company of dedicated people with great character to establish a culture of innovation, collaboration, service and uncompromising quality,” he says.

Jim Lauria is vice president of Sales & Marketing for Mazzei Injector, a fluid design company that manufactures mixing and contacting systems. Source: Mazzei Injector, which is solely responsible for the information provided and is wholly owned by the source. Informa Business Media and all its subsidiaries are not responsible for any of the content contained in this information asset.

See our selection of Mazzei venturi’s for ozone injection HERE

State of the Ozone Water Treatment Industry

Ozone is a widely used agent for water treatment including public drinking water, industrial wastewater, purification of process water, aquariums, bottled water, ground water remediation and aquaculture, among many others. Ozone finds value in these applications because it can provide multiple benefits in water treatment while decomposing back to oxygen after use. The benefits of ozone include:

•Disinfection – ozone is a biocide that can inactivate a wide range of microorganisms including virus and bacteria.
•Oxidant – ozone is capable of directly oxidizing various organic compounds, including those of emerging concern such as pharmaceuticals and personal care products found in our drinking water sources, as well as organic compounds found in industrial wastewater.
•Advanced oxidation – In combination with peroxide or UV light, ozone can be the base of an advanced oxidation process that can oxidize virtually any organic compound including difficult to treatment materials such as 1,4 dioxane.

This article will touch on some of the major existing applications and some emerging applications for ozone.

Public drinking water treatment
Chart 1 shows the distribution of ozone use in US public drinking water. Ozone provides several benefits to drinking water facilities. These include primary disinfection, taste and odor removal, color removal, removal of inorganic materials such as Fe, Mn and H2S, enhanced filtration via a micro-flocculation effect and removal of certain organic compounds. In a well-engineered process, several of these benefits can be achieved in a single injection of ozone. Being able to accomplish several treatment objectives at the same time make ozone an excellent choice for certain drinking water plants. This explains the growth of ozone for this application.

Municipal wastewater reuse
Because of water shortages caused by growth in water demand as well as loss of water supply caused by drought, more cities are thinking about reusing their wastewater for drinking water, either directly or indirectly. Several facilities have already been built using membrane-based technologies. This is a proven approach but comes with several notable drawbacks. First, you need a find a place to dispose of the waste brine rejected from the RO membranes. In coastal locations, the brine can be rejected to the ocean. In other locations it is not as simple. The second factor is cost, because of the high pressure needed in RO membranes, the electrical demand to treat the water is high.

Ozone in combination with biologically active filters (ozone-BAF) can be used to treat municipal wastewater to achieve high degrees of water purity at lower cost than membrane processes and without the need to dispose of a brine waste. Currently, large scale trials are being run by the Hampton Roads Sanitation District, in Eastern Virginia to demonstrate this technology through their SWIFT project. Other water authorities are also running ozone-BAF pilot trials. If successful, ozone-BAF could provide inland wastewater facilities with a technology to reuse their wastewater for drinking water.

Advanced oxidation processes
Another emerging application for ozone is in advanced oxidation. Advanced oxidation refers to processes that produce hydroxyl radicals (•OH). The hydroxyl radical is one of the strongest and fastest acting oxidants that can oxidize virtually any organic compound. They can be produced in a variety of ways, but ozone with peroxide and ozone with UV are two such methods. The advantage of the ozone routes is that little if any by product is left after complete and pH adjustments are not required. An important application of ozone based advanced oxidation is the removal of 1,4 dioxane from ground water contaminated with solvents. Dioxane is not readily air stripped from water, absorbed on activated carbon, or oxidized by most chemicals. Advanced oxidation by ozone and peroxide has been proven to be effective in removing the dioxane from the water via oxidation. Ozone with peroxide has also found use in industrial wastewater applications where other methods were not able to remove difficult to treat organic compounds. The use of advanced oxidation appears to be a growing technology for water treatment and ozone-based processes are a growing part of this application.

Biosolids reduction
Wastewater treatment plants utilizing the activated sludge process typically produce excess sludge that needs to be removed and disposed of from the process. Ozone has been shown in the literature and in commercial application to offer an alternative method for reducing excess sludge. This process involves exposing a portion of the activated sludge to ozone. Some of the bacteria that make up the sludge are lysed via exposure to ozone releasing COD into the wastewater. Even though some of the cells are damaged or killed, the overall process generally does not show an increase in BOD/COD leaving the process.

Depending on the amount of ozone required per unit of sludge removed and the costs associated with the current handling of the excess sludge, ozone can represent an economical alternative with conventional sludge handling processes. Ozone also offers other potential advantages to the activated sludge process including a reduction in bulking/foaming, scum control and improved denitrification. A number of wastewater treatment plants in Europe have adopted this technology and have realized a 30-40 percent reduction in excess sludge with no loss of wastewater treatment performance. A new installation is planned for the US later this year at a chemical manufacturing plant.

PFAS removal
PFAS are a group of various fluorochemicals including PFOA, PFOS, among others. They are of emerging concern since they are distributed widely in the environment, do not readily breakdown in the environment/human body and can accumulate over time. There is some evidence that they may have adverse impacts on human health. US EPA points to studies of PFOA and PFOS that show: reproductive and developmental, liver and kidney, and immunological effects and tumors in laboratory animals. As a result, the agency is studying regulation of these compounds.

A novel approach to PFAS removal is ozofractionation. Ozofractionation is a form of foam fractionation, a method to remove hydrophobic materials from water. In ozofractionation, ozone is used an oxidant, as well as the foam-forming gas. Proposed advantages for using ozone as the bubble forming gas include co-contaminant reduction and smaller bubble sizes. Smaller bubbles result in higher surface area to volume ratios and thus more material can be captured for a given volume of gas. Formation of hydroxyl radicals around the bubbles may result in negative charges that better hold the PFAS molecule.

Conclusion
Ozone continues to find new applications in water treatment while expanding its existing applications. The future looks bright for the use of ozone in various parts of the water treatment industry.

Click Here to Contact Us Today and speak with an ozone expert!

Source – Anthony Sacco from Water Conditioning & Purification International Magazine (https://wcponline.com/2021/08/15/state-of-the-ozone-water-treatment-industry/)