Home

Technology

Bubble generators

Filters

Probiotics

Blog

About

Ultrafine Bubble-enhanced ozonation for water treatment

In Blog by Erik van Berkum Published: Friday, 7 July 2017

Credit: Photo by US Dep. Agriculture / CC BY

Vegetable washing process

GreenGate Fresh provides fresh salad produce across America. They use a 6-step washing process and even with the current water conservation policies they still use 300.000 gallons of water per day at one of their locations. For the salads washing process they need water of around 40 degrees Fahrenheit and to get this they must cool down the water, which is an energy intensive process. Isaac Hung student at the University of Arizona wrote a thesis for his master of science study, seeking ways to cut the company's water, energy, and chlorine usage by introducing technologies, to allow part of the wash water to be recycled.

Currently, GreenGate Fresh is treating water used to process lettuce and other fresh produce with hypochlorite, to disinfect the harvested produce. The benefits of hypochlorite are it is an industry standard in the US, its low cost and its effective. Residuals that stays on the produce continue to inactivate and suppress regrowth of bacteria, which is another benefit compared to other technologies. Ozone is another USDA approved disinfection method for organic certified produce. Ozone is a highly reactive oxygen free-radical and has a greater oxidative potential than chlorine. As a result, ozone is used a lot in many disinfection applications. A disadvantage of ozone is, its short lived and doesn't create any residual to prevent regrowth of pathogens.

Ozone Ultrafine bubble research for water treatment

In some studies, it has been observed that in certain cases water containing fine bubbles and ultrafine bubbles have been effective in removing biofilms and killing bacteria given a long enough treatment time. For GreenGate Fresh the treatment times can range from several hours to a day the fine-bubbles by themselves would not be sufficient for the water treatment needs. However, the fine-bubble properties of not rising to the water surface and slowly diffusing gas into the water allows for over-saturation of gas in water and make it desirable to combine fine-bubble technology with ozone gas treatment.

The purpose of the research is to find out., whether ultrafine bubble technology can be beneficial for the treatment of captured produce wash water effectively. The following 3 items were researched:

  1. Compare the disinfecting effects of injecting ultrafine bubbles in the nanometer range with the effects of injecting find bubbles into contaminated water.
  2. Determine the effects injecting ozone gas as ultrafine bubbles in the nanometer range into water has on dissolved ozone concentration over time compared with injecting ozone gas as fine bubbles.
  3. Determine if ozone gas injected into water as ultrafine bubbles is available in contaminated water for treating water.

Its is generally accepted that the time required for a micro bubble to collapse is only several minutes, because of the collapsing bubble hydroxyl radicals are produced which aid in disinfection of pathogens. In the study two fine-bubble generators were used, one of them was the gaiaGaLF UFB mixer , as a control, air diffusing stones were used. The effect of micro-bubbles on ozone dissolution and dwell time. Compared to the micro-bubble and ultrafine bubble generators, bubbling ozone into water resulted in about the largest dissolved ozone concentration in the water. However, injecting ozone as micro-bubbles and ultrafine bubbles allowed the dissolved ozone concentration to rise to the maximum concentration in about a third of the time it took for bubbling ozone into water with the air diffusers to reach the largest concentration. Furthermore, when ozone was injected into water using micro and ultrafine bubbles, the concentration of dissolved ozone in the water decreases at a slower rate than when ozone was bubbled into water using air-stones.

Conclusion use of ozone bubble technology

The experiments successfully demonstrated that ultrafine bubbles by themselves do not seem to have any disinfecting effect on the water. There are benefits pairing ultrafine bubble technology with ozone gas for water treatment. By injecting ozone, it is possible to make higher levels of dissolved ozone in the water at the same water temperature or the same levels of dissolved ozone at higher water temperatures than if ozone gas was injected into water using conventional methods. As ultrafine bubbles do not rise to the surface much less ozone is injected into the water. Finally, ultrafine bubbles are more stable, allowing gaseous ozone to slowly dissolve into water and due to the stability ozone remains longer present in the water.

Credit: Photo by US Dep. Agriculture / CC BY

More information about the research: University of Arizona Open Repository
The full report in pdf: Ultrafine bubble-enhanced ozonation for water treatment

ultrafine bubbles | research | micro bubble | nano bubbles | disinfection | cleaning | ozone | water treatment | gaiaGaLF |

Recent Posts

Ultrafine Bubbles and the effect on Seed Germination

Nano Bubbles are useful in accelerating the metabolism of living organisms, but the mechanism is not yet well understood. In a study, they investigated the production of reactive oxygen species (ROS) by Nano Bubbles and the effect on seed germination. The conclusion of the study was seeds in nano bubble water had a higher germination rate than all those submerged in the different other conventional used solutions.

Project report water treatment lake gaiaGaLF nano bubbles

A contaminated pond which was used for irrigation was treated for 40 days with nano bubbles. After treatment the algae contamination problems was solved. For the treatment the gaiaGaLF nano bubble generator was used, in combination with an connected oxygen concentrator.

Demonstration gaiaGaLF submersible unit

The gaiaGaLF submersible unit is a, complete unit with the low-pressure mixing valve technique that effectively and efficiently saturates liquids with gases over 5 times the levels of conventional technologies. The unit moves 113 liters of water per minute and dissolves 4 liters of oxygen per minute creating a high DO content and ultrafine bubbles in the water.

Strong increase in cannabis production with bubble Oxygenation

Root systems require oxygen for aerobic respiration. Reduced levels of oxygen in the rootzone, slow down plant growth and increase susceptibility of diseases. Indoor grown plants in closed water systems have often a lack of oxygen and need additional oxygen supply. By delivering ultrafine bubble to the rootzone of the plant, you increase the levels of oxygen and the water get negatively electrically charged this promotes nutrient uptake and hair root growth. Read the whole article to see what experience cannabis growers have to say about the ultrafine bubble system.

Lab demonstration miniGaLF

The miniGaLF is ACNITI`s entry level GaLF model designed for companies, universities, research institutes and individuals that want to learn about Ultrafine bubble technology. In this blog a movie is shown of the connections and the performance to create ultrafine bubble (nano bubbles) with high DO water.

Cultivate attractive lettuce with no more tipburn

Manoa lettuce is a lettuce variety susceptible to tipburn. Tipburn is the drying and dying of leaf tissue along the edges of the leaf. During a test at a grower in Hawaii it was shown that by increasing the DO levels and adding ultrafine bubbles, reduction of tipburn is realized and quality and production improvements are made.

What's in the name: ultrafine bubbles or nano bubbles?

Interested to know why nanobubbles are officially called ultrafine bubbles? In this article we explain the reasons why the ISO technical committee has decided to use the official name ultrafine bubbles instead of nanobubbles.

Payments

acniti accepts bank payments, PayPal and many major credit cards Visa, MasterCard, American Express, Discover, JCB, Diner's Club and EnRoute.

Processwire loving it

A write-up of how the acniti website is built, which tools are used for development, like PhpStorm and Ubuntu! The website is built with Processwire and the hosting is on AWS. Also insight is given in which Amazon Web Services are used and how they work together. The last part of the article shows tools that help write the content and how the site is promoted on the major and branch specific social networks.

Laundry clean with a bubble boost

Washing of surfaces and laundry is one of the promising areas were ultrafine bubbles can make a difference in the application. Reducing the amount of detergent, has a positive effect by reducing pollution, washing laundry without detergent, would greatly benefit the environment. Ultrafine bubbles can lower the surface tension of water, the large amounts of oxygen molecules in bubbles charge the water negative.

Ozone bubbles for water treatment

Research into ozone ultrafine bubble technology for the treatment of captured produce wash water. The white paper shows that their are benefits in using the technology, by better disinfection and savings in ozone can be obtained.

Bubble sizes and properties

Bubbles are gas filled cavities in water. The contact area between bubbles in water filled with tiny bubbles is much larger than water filled with bigger bubbles. The gas pressure inside a small bubble is higher than in a large bubble, therefore the surface tension of a small bubble is higher as well.

Self-cleaning inlet filter explained

Self-cleaning Filters prevent pumps from blocking and make aeration more efficient

Self-cleaning inlet filter demonstration

Video: Rotorflush Self-cleaning inlet filter explained

Ultrafine bubble generation

There are various technologies to generate ultrafine bubbles. This article gives an overview of the most used techniques, such as pressurized dissolution, static mixers, and rotational flow.

Contact

acniti contact page, for all questions, quotes and more information about the products.

ISO fine bubbles

Great things happen when the world agrees, fine bubbles are an innovative technology, but without proper standards for the industry development, there are obstacles. From 2013 ISO started the creation of an International Standard for fine bubbles popularly know as nano bubbles.

gaiaGaLF lake Ida Anne

Lake Ida Anne has a growing problem with algae in spring and summer. A large number of nutrients are available in the lake, and this promotes algae growth. The city of Langford tested the Gaia Oxygenation System to combat the algae, with great success.

Long distance fish transport with fine bubbles

A new innovative way to transport fish while sleeping is almost ready to go onto the market. A combination of CO2 and ultrafine bubbles make this possible.

Brand Assets

acniti brand assets and resources, corporate house-style

Ultrafine bubbles on camera

Ultrafine bubbles movie, movie made with the Malvern NanoSight.

miniGaLF Plus

The miniGALF is IDEC`s entry level GaLF model designed for first experiences with ultrafine bubble technology. The miniGaLF -Plus enables higher concentration of ultrafine bubbles by multi-passes of water through the miniGaLF.

The fine bubble breakthrough

Imagine your kitchen floor or bathroom tiles being cleaned by very tiny bubbles. Sounds great, a new technological era is dawning.

Smart people talk bubbles, the water innovation

Bubbles are all around us, in our foods, beer, pop drinks bread and cheese, but also in the bricks of our house. Bubbles are gas-filled cavities in water, the lifetime of a bubble is short at most a few minutes, only ultra-fine bubbles are stable for longer periods like months, that is making them very special and that enables us to change the properties of water.

Photostream