Limits on Phenol were lowered from 50 ppm to 1 ppm for an acceptable discharge limit to the municipal wastewater system.  This presented a problem to our customer as phenol levels from various locations could range from very low, to well over 50 ppm.  All of this water is mixed together in equalization tanks and processed with chemical processes, and ultra-filtration.  None of these processes were able to lower the phenol level below 8-12 ppm on average.

What is Phenol?

Phenol is an organic compound - C₆H₅OH.  Phenol is also known as carbolic acid.  Phenol is found in petroleum products, detergents, herbicides, and pharmaceutical drugs.  High levels of phenol are toxic and can cause permanent health issues.

Initial pilot test:

The first ozone pilot test consisted of a 300 g/hr ozone injection system recirculating water in the 5,000 gallon over a period of 12 hours of time.  This did successfully lower phenol levels and prove that ozone was a viable solution. See chart below for data:

This data did confirm that ozone was a viable option.   However, lower phenol levels were required, and a better process was required for process flow situations.

Final Pilot Test:

After initial processing the wastewater is stored in 5,000 gallon holding tanks prior to discharge.  Overall water flow rate for the processing plant is an average of 10 GPM when averaged over a 24 hour time-frame.  We decided to pull water from one holding tank treat that water with ozone at 10 GPM and pump that water to a second holding tank.

This new setup allowed for a 100 gallon contact tank to be used that could be operated under pressure up to 35 PSI to improve mass transfer of ozone into water.  Also, the smaller 100 gallon tank allowed for very high dissolved ozone levels to be maintained for about 10 minute of contact time.  See diagram below for details on this set-up:

Using the same 300 g/hr ozone injection system 300 g/hr of ozone was introduced into the water flow rate of 10 GPM for an effective ozone dosage rate of 132 mg/l.  Despite this lower ozone dosage rate improved phenol reduction was achieved.  This did achieve an acceptable phenol level of less than 1 ppm.  Phenol levels up to 12 ppm were consistently reduced to less than 1 ppm at water flow rates up to even 12 GPM, an ozone dosage rate of 110 ppm.

Cost Savings:

Phenol removal prior to ozone was performed with carbon vessels.  These did work well and achieve the necessary phenol reductions.  Carbon replacement was necessary every 2-weeks at a total cost of $15,000/month.  An ozone system to replace this carbon was rented at a cost of $3,900/month.  With electric and all maintenance costs total costs were still less than $5,000.month for a total savings of $10,000/month.

Conclusion:

This pilot test did show good results and proved two things.

First: Phenol reduction with ozone, in heavy industrial wastewater is possible and can be cost effective.

Second: using proper ozone mass transfer methods the efficiency of phenol reduction, and likely many other contaminates with ozone is much more efficient and offers large cost savings.

For more information on phenol reduction with ozone click here, to review the multiple papers published by the IOA.

Follow this link to learn more about ozone use in wastewater treatment

The post Phenol reduction with ozone in industrial wastewater appeared first on Ozone Journal.

Ozone reduces fungicide residues on grapes

What is better than juicy red grapes sliced and sprinkled atop a leafy salad? Or what warms your heart more than seeing your child devour cluster after cluster of the succulent berries on a Saturday afternoon? After all, it’s not just a burst of sweetness that grapes offer with every bite–their flesh is saturated with vitamins C and K; their seeds, with antioxidants. So eating a lot of grapes is a good thing, right?

Yes and no. While it’s true that grapes ARE loaded with nutrients, it’s also a fact that they are exposed to chemicals–a LOT of chemicals. Grapes and their vines are fragile, and without the aid of modern agricultural pesticides and fungicides, those pretty grapes you feed to your children would have died and turned to compost long before making it to your kitchen table.

So how do we assist the survival of the grapes, and yet avoid ingesting those chemicals? This is where ozone steps in. A recent study shows that exposing grapes to ozone can reduce grapes’ fungicide residue.

In this study, a research team ran a trial to see if ozone exposure would increase the breakdown of fungicide residue on “Thompson Seedless” table grapes.

The grapes in the trial were treated with various fungicides. The grapes were then put into storage for 36 days. During the storage period, the control group was exposed to zero ozone. The trial group was exposed constantly to 0.3 PPM ozone.

While common grape fungicides do naturally break down over time, the study found that ozone helped several of the fungicides break down more rapidly. At the end of the 36 day trial period, the grapes in the control group still had 59.2% of the fungicide residue present. The grapes exposed to ozone, on the other hand, had only 35.5% of their fungicide residue remaining.

Further study is needed to determine if the chemicals resulting from the reaction between the fungicides and ozone cause negative health effects. In the meantime, though, ozone beckons as a hopeful assistant in keeping our grapes as clean and healthy as possible.

Link here to the original article, written by Emanuela Fontana. You can also purchase the complete study, published by the scholarly journal Postharvest Biology and Technology.

The post Ozone Makes Grapes Safer appeared first on Ozone Journal.

The post Ozone used to treat herniated discs appeared first on Ozone Journal.

Aflatoxin is a mycotoxin that is produced by a fungus (aspergillus).  In climates where mold may grow on grain while it is growing in the field high levels of aflatoxin on grain may be an issue.  Aflatoxin is a pathogen that can cause health issues in both humans and animals.  The FDA has established action levels for Aflatxin for human and animal consumption that rage from 20 – 300 ppb.

With the rising prices of corn and other commodities the practical removal of unsafe levels of aflatoxin can be a necessary part of cost effective agriculture.

While there is a fair amount of lab data available, actual real-life data on the use of ozone to remove aflatoxin in corn, is not shared as much as other application.  Recently we worked with a customer that did share the following information.

He used a 300 g/hr ozone generator on 6 bushels of corn for 2 hours of time.  This reduced the aflatoxin levels from 58 ppb to 2 ppb.  In further testing he was able to scale this to larger volumes of grain with lower ozone levels and longer periods of time.  Thus, showing the potential of ozone use in a grain bin on a large scale over numerous days of ozone treatment.  Also, he found that corn with higher levels of moisture showed improved results vs dry corn.

In addition to this data, we are currently in the process of building an ozone trailer with the capacity of 2,500 g/hr ozone generation for a customer in Indiana.  This was secured after numerous on-site pilot tests with ozone were performed with ozone rental equipment.

On a large scale ozone gas can be introduced into the a grain bin aeration system.  We have found that higher ozone concentrations have better results, and that the grain should be mixed or agitated during the process to ensure that all of the contaminated corn is contacted with ozone gas.

For additional information review the links below for technical papers on this topic:

Evaluation of Aflatoxin-Related products from Ozonated Corn

Efficacy and safety evaluation of ozone to degrade aflatoxin in corn

 Ozone has also proven effective removing aflatoxin from other foods.  More papers linked below:

Ozone used for reduction of aflatoxin in peanuts

Ozone used for reduction of aflatoxin in pistachios

Ozone used for reduction of aflatoxin in cottonseed and peanut meal

 To learn how we can put our experience to use for you, contact us today.

The post Degradation of Aflatoxin in Corn using Ozone gas appeared first on Ozone Journal.

Ozone: Science & Engineering, Vol. 35, No. 3, 01 May 2013 is now available on Taylor & Francis Online.
This new issue contains the following articles:

Editorial 
Editorial
Barry L. Loeb

Pages: 147-148
DOI: 10.1080/01919512.2013.772452

Original Articles
The Electrochemical Generation of Ozone: A Review
Paul Andrew Christensen, Taner Yonar & Khalid Zakaria
Pages: 149-167
DOI: 10.1080/01919512.2013.761564

Process Control For Ozonation Systems: A Novel Real-Time Approach
Hans-Peter Kaiser, Oliver Köster, Markus Gresch, Philipp M.J. Périsset, Pascal Jäggi, Elisabeth Salhi & Urs von Gunten
Pages: 168-185
DOI: 10.1080/01919512.2013.772007

Determination of Rate Constants for Ozonation of Ofloxacin in Aqueous Solution
Gracia Márquez, Eva M. Rodríguez, Fernando J. Beltrán & Pedro M. Álvarez
Pages: 186-195
DOI: 10.1080/01919512.2013.771530

Substitution of Reduction Clearing Step by Ozone Treatment at Disperse Dyeing of Polyester
Hüseyin Aksel Eren, Seda Gundogan, Semiha Eren & Barış Kocaman
Pages: 196-200
DOI: 10.1080/01919512.2013.771551

Effect of Ozone and Peroxone on Helminth Hymenolepis nana Eggs
Gabriela Ibañez-Cervantes, Clementina Rita Ramírez-Cortina, Adrián Márquez-Navarro, María Soledad Alonso-Gutiérrez, Gloria León-Ávila, Gregorio León-García & Benjamín Nogueda-Torres
Pages: 201-207
DOI: 10.1080/01919512.2013.771762

Effect of Ozone in UF-Membrane Flux and Dissolved Organic Matter of Secondary Effluent
M.T. Orta de Velásquez, I. Monje-Ramírez & J.F. Muñoz Paredes
Pages: 208-216
DOI: 10.1080/01919512.2013.771940

Inactivation of Norovirus Surrogates after Exposure to Atmospheric Ozone
Jennifer L. Cannon, Grishma Kotwal & Qing Wang
Pages: 217-219
DOI: 10.1080/01919512.2013.771953

Comparative Analysis of Energetic Properties of Ti6Al4V Titanium and EN-AW-2017A(PA6) Aluminum Alloy Surface Layers for an Adhesive Bonding Application
Michał Piotr Kwiatkowski, Mariusz Kłonica, Józef Kuczmaszewski & Saburoh Satoh
Pages: 220-228
DOI: 10.1080/01919512.2013.772436

Investigation of Ozone Concentration Measurement by Visible Photo Absorption Method
Kenji Teranishi, Yoji Shimada, Naoyuki Shimomura & Haruo Itoh
Pages: 229-239
DOI: 10.1080/01919512.2013.780544

The post New Ozone : Science & Engineering Journal Available Volume 35, Issue 3 appeared first on Ozone Journal.

Creating ozone inside food package

Ever grab an apple out of the fruit bowl as you’re heading out the door, only to realize as the door clicks behind you that you forgot to wash it? If you’re like me, you don’t bother unlocking the door and going back inside to wash the apple. You quickly rub your sleeve over it and take the first bite, knowing even as you do so that you are leaving the bacteria alive and well on the apple’s skin.

What if you didn’t need to wash the apple, or even rub your sleeve over it? Kevin Keener, a food science professor at Purdue University, is doing a study on a method for ozonating fruit before it leaves its package. He has found that creating ozone inside a plastic bag of fruit kills food-borne bacteria. Even E. coli bacteria is killed after just 45 seconds of treatment.

It appears from the experiments so far that the quality of the food is not affected by the ozone treatment, although more studies will be performed in the future to ensure the quality of the food undergoing this treatment.

Link here to the original article, written by Brian Wallheimer.

The post Ozone Kills Bacteria on Packaged Fruit appeared first on Ozone Journal.

The article cites a Swedish study where perch, a type of schooling fish, were pulled from rivers downstream of a wastewater treatment facility.  These fish showed a bio-accumulation of Oxazepam, an anti-anxiety medication.  Further lab testing showed that perch exposed to higher levels of Oxazepam became more agressive and willing to strike out on their own.

This sort of behavior is completely out of the ordinary for schooling fish.  Indeed, a solitary schooling fish on its own in nature would almost certainly lead to its untimely demise.  So while this particular drug is not toxic to the fish in a classic sense, it could have detrimental affects on fish populations due to changes in behavioral mechanisms.

How does this relate to the world of ozone?  Current wastewater treatment technology fails to break down most micropollutants, including pharmaceuticals, which allows them to pass calmly into our rivers and lakes.  One possible solution being tested by wastewater researchers is the use of ozone to combat these micropollutants.  If the introduction of ozone does indeed prove successful at removing micropollutants from wastewater, it is one solution that may stem the ever-increasing tide of pharmaceuticals produced by our modern society.

If not, we can at least look forward to a future boom in wild-caught fish for the treatment of anxiety.

For more information about ozone research relating to micropollutants and pharmaceuticals, check out the IOA’s Ozone Engineering journal abstracts by searching the links here:

Ozone Pharmaceutical Research

Ozone Micropollutant Research

The post Pharmaceuticals in FIsh appeared first on Ozone Journal.

pH Sensor (top) is an add-on feature for the Q45H Dissolved Ozone Meter

Ozone Solutions now offers a pH sensor as an add-on feature for the Q-45H Dissolved Ozone Meter. This pH sensor can be mounted on the top of the Q-45H flowcell.

The post Simultaneous pH and Dissolved Ozone Monitoring appeared first on Ozone Journal.

While these incidents can certainly become overblown by mainstream media (as media will do), that makes them no less significant to the ozone industry – it is public perception that counts.  Where truth and media coverage collide, media coverage always has the upper hand.  The matter is complicated further when ozone exposure incidents lead to civil suits – miring ozone-use facilities and ozone manufacturers in substantial legal expense and additional bad publicity.

Unfortunately, it is possible that these recent incidents could have been avoided if more care had been given to proper ozone detection equipment and proper ozone safety procedures.  Whether you have a facility using ozone or are a manufacturer producing ozone systems, this is a lesson that needs to be taken to heart.

OSHA requirements dictate that ozone levels cannot exceed 0.1 ppm, so for the sake of expense many organizations implement a single monitor to satisfy the regulation.  As applications for ozone increase, however, the number of individuals that work in the vicinity of ozone systems will also increase.  While the increasing number of individuals does not increase the likelihood of an ozone leak, it does increase the likelihood of exposure if a leak does occur.  For that reason, the extent of ozone safety equipment and training at a facility should instead be based on the likelihood of exposure – not just OSHA regulations.

What does this mean, exactly?  Take these examples:

At a small company where all employees are familiar with ozone and fully trained in the use of their ozone system, a single or small number of monitors may be sufficient for employee safety.  (As always, this also depends on proper maintenance, adherence to proper procedures, etc.)

At a large company, there may only be a handful of employees that use an ozone system and are familiar with its use.  These organizations should implement additional ozone monitors and safety signage in any area where “non-ozone” employees may be present.  This helps ensure that all employees in all areas can remain safe and act appropriately in the event of an ozone leak.

Public facilities need to take their safety measures one step further.  In a facility where the general public could be exposed to an ozone leak, all areas need to be monitored (with redundancy where possible), proper maintenance should be observed, ventilation should be present, ozone equipment rooms should have limited access and staff should be trained in how to handle an ozone leak.

Regardless of how careful a company is, ozone leaks are a reality.  As users of ozone equipment, please keep this in mind as you plan your ozone systems and then communicate your safety requirements to us as we help with the design process.  As a manufacturer, Ozone Solutions will continue asking questions to ensure that the equipment we sell is being sold with proper detection equipment installed.  Together we can help the ozone industry continue its stellar record of safety for another 100 years.

Further Information Regarding Ozone Safety

• OSHA and Ozone
• Ozone Health Effects
• Ozone MSDS
• Ozone Leaks

Further Information Regarding Ozone Detectors

•  Ambient Ozone Detectors
• UV Ozone Analyzers

The post Ozone Safety in the News appeared first on Ozone Journal.

Electrochemical Ozone Sensors

An electrochemical ozone sensor uses a porous membrane that allows ozone gas to diffuse into a cell containing electrolyte and electrodes. When ozone comes into contact with the electrolyte, a change in electrochemical potential occurs between the electrodes causing electrons to flow.

In “zero air”, little or no electron flow occurs. As the presence of ozone increases, the electrical signal increases proportionally. The monitor interprets this signal and displays the ozone concentration in PPM (parts per million).

Advantages

• Linear response
• Good repeatability and accuracy
• Very quick response time (1-2 seconds)
• Long battery life
• Can measure ozone accurately up to 20 ppm
• Moderate resistance to interference

Disadvantages

• Humidity can affect sensor
• Sensitive to EMF/RFI
• Limited sensor life (12-18months), even if in storage.
• Less accuracy at low ozone levels (below 0.1 ppm)

Applications:

• Personnel (portable) safety monitoring (esp. long shifts)
• Ozone Leak Detection
• Stationary ozone monitoring
• Ozone Monitoring & Control

Semiconductor-Based Ozone Sensors
Heated Metal Oxide Sensor Cell (HMOS)
Gas Sensitive Semiconductor (GSS)

A heated metal oxide semiconductor (HMOS) sensor works by heating a small substrate to high temperature (around 300-deg F / 149-deg C). At this temperature, the substrate is very sensitive to ozone and exhibits a change in resistance that is proportional to to the amount of ozone which contacts its surface. The circuitry of the monitor interprets this change in resistance and displays the corresponding ozone level on the display as either PPM or PPB.

Advantages

• Very responsive to low levels of ozone ozone (below 0.1 ppm)
• Least expensive monitoring technology
• Excellent repeatability and accuracy
• Long Sensor Life if stored properly

Disadvantages

• Slow start-up (can require 8-24 hours warm-up time)
• Slower response time to ozone (compared to electrochemical)
• Very sensitive to interference
• Shorter battery life due to heated sensor element
• Not linear at ozone levels above 1 ppm
• Ceiling Temperature threshold of 122F or less (depending on model)

UV absorption

The Ozone molecule has an absorption maximum at 254 nm. A UV lamp emmiting 254 nm wavelength of light is used to measure the absoption of ozone within a chamber. This is measured via a photodiode with a built in interference filter centered on 254 nm wavelength

Advantages

• Very accurate (within 1%)
• Very linear at any ozone levels
• Low ppb detection limits with accuracy
• Minimal cross sensitivity to other gasses or interferences
• Can read high concentrations (20% or higher)
• Durable design with excellent longevity

Disadvantages

• Higher cost
• Physically larger
• Bench mount (no handheld)

Badge/strip

Ozone badges are one time use cards that use a color change indicator. The indicator used is a small paper strip or circle that is oxidized in the presence of ozone.

Advantages

• Easy to use
• Low Cost
• Specific to OSHA 8-hour PEL

Disadvantages

• One-time-use
• Very cross-sensitive
• Low detection limits

The post Ozone Sensors – Technology Comparison appeared first on Ozone Journal.