Ozone used to save water in garment manufacturing

Ozone is instrumental in helping reduce water consumption in garment manufacturing.  Levi Strauss has learned innovative techniques and is now sharing this information with the world.  Read below:

Read full article here

Levi Strauss Water innovation Manual can be downloaded here

Ozone

  • Water savings counted:  A bleach bath and a generic neutralization bath
  • Average water savings: 12 liters/ jean
  • Frequency of use: Moderate

Traditionally used to clean up garments, ozone, a powerful oxidant, has been used in finishing for some time. As a Water-less technique, higher concentrations of ozone achieve more pronounced lightening effects, effectively replacing many uses for wet bleach baths.

Lightening a garment with a wet bleaching agent typically requires three wet baths: a bleach bath, a neutralize bath, and a rinse bath. If ozone use comes in the middle of a finish formula, it saves all three baths. If ozone use is the first step in a formula, it only saves two baths because the garments need to be wet before being loaded into the machine. Since vendors apply the technique in different ways, they may save two or three baths. Therefore, we conservatively count the water savings from only two baths, the bleach bath and a generic neutralization bath.

Additional notes:

  • Ozone can be used on indigo or black sulfur fabrics.
  • Use of ozone requires up-front investment in the ozone machine and the generators, along with safety training for workers.

UV Ozone Analyzers for Ozone Detection

Oxidation Technologies is now your one stop shop for all your UV ozone analyzer needs.  We now carry the following brands:

  • Eco-Sensors
  • Aeroqual
  • 2b Technologies
  • API-Teledyne

We do service, sell, and calibrate all brands of ozone analyzers, but sell these primary brands.  We can meet all needs from 1 ppb detection, to high range 20% by weight and greater measurements.  Call us for details for your accurate UV ozone measurement needs.

New UV Ozone Analyzers

We also rent ozone analyzers and sell used and refurbished ozone analyzers

UV-100 Ozone Analyzer for rent
UV-100 Ozone Analyzer for rent

The UV-100 will measure ozone from 0-1,000 ppm.  Internal sample pump will allow the user to pull ozone from one location, into and through the ozone analyzer to measure ozone levels in a process.  UV-100 ships with a carry case and all accessories needed for operation.

API 454 O3 analyzer for rent
API-454 High Range ozone analyzer for rent

View our complete line of rental products here

Our list of used products changes frequently, click here for updated list, and continue to check back frequently.

Ozone used to stop mold in plant growth

Ozone is commonly used to eliminate mold, and to stop mold from growing.  A new trend and industry is the industrial growing of cannabis.  In this application mold growth can be a major issue.  Article below gives some great info on the use of ozone to eliminate mold growth in this industry:

Read full story below:

Grow Hack: Prevent Mold During Growth, Curing and Storage

Mold-rated UV-C lights are great mold protection in other parts of the garden as well. Placing UV-C lights in front of HEPA filters in air intakes assures that the mold spores it captures do not turn the filter itself into a breeding ground. In addition, shine UV-C light on the cooling tubes and drip pans of your air-conditioning unit to assure that mold does not proliferate in these high-risk areas.

Use precaution when handling UV lamps. Do not let the light shine on any part of your body; it may present a hazard to your skin. Additionally, UV lights present a danger to your respiratory system due to the formation of ozone. Ultraviolet light reacts with molecular oxygen (O2) to form ozone (O3) in small quantities. Ensure that any area under UV irradiation has an adequate airflow. Regulations state that workplace or residential atmospheres must not exceed a level of 50 parts per billion of ozone. Any grow operation that wishes to withstand OSHA regulations must measure ozone concentrations in UV-irradiated areas to assure they do not exceed 50 ppb, as higher concentrations present a health hazard. Ozone tests can be expensive, so try and use your nose first; if you are able to smell the ozone (a smell reminiscent of laser printers in use), you definitely need more ventilation.

 

Effect of ozone half-life in water

How to correctly calculate Residual Ozone Concentration for an Ozone Water Treatment Application.

We highly recommend this information in order to help ozone water treatment professionals to correctly take in account the fact of ozone destruction in water at different temperatures due to the relatively short half-life of ozone.

 Failure to apply this information to the calculation in ozone treatment applications may result in ozone concentration considerably lower than required and could make ozone application completely ineffective.

 Contrary to myths that it is impossible to have a residual ozone in the water or that ozone could survive in the water only for a few seconds here is the factually scientifically proven data on half-life of ozone according to scientific sources.:

 Typical O3 Half Life Time as a Function of Temperature:

 Dissolved In Water (pH 7)

Half life time at Temp Half life time at Temp

 ~ 30 minutes 15 ºC

~ 20 minutes 20 ºC

~ 15 minutes 25 ºC

~ 12 minutes 30 ºC

~ 8 minutes 35 ºC

When half-life of ozone at 30C is about 12 minutes, that means that every 12 minutes there will be 50% less ozone in the water if we some how injected the ozone instantly.

 However, in the real life we inject ozone in to the water 24/7 constantly adding it and maintaining the concentration and not instantly.

 Therefore, the idea is to inject enough ozone to the pool that it would compensate for half-life of ozone destruction and that will allow us to have a constant desired residual ozone concentration in the water.

 As an example of using the above information, let us say we need to maintain a concentration of 0.1 ppm in the pool water.

We know that 1ppm=1 g/m3

 If the water tank or swimming pool is 100 m3 the 10 g of ozone dissolved will create that concentration 10 g. (100 m3 x 0.1 g/m3 = 10 g)

 We also know that 12 minutes = 0.2 hour (12 min/60 min=0.2h)

 It is understandable that every 12 minutes 10 grams of ozone dissolved in the water becomes a 5 g, 2.5 g, 1.25 g…, etc., we will have to inject more ozone to compensate for it.

 If we divide the amount of ozone required by the half-life of ozone in water, we will get the amount of ozone required to be injected every hour to compensate for it.

 We suggest the following formula:

O3 n/HL=O3 c

 Were :

O3 n – Not compensated for half-life of ozone destruction amount of ozone required to achieve and maintain desired ozone concentration,

HL – Half-life of ozone according to the water temperature from the table above

O3 c – Compensated or actual amount of ozone required to be injected in order to maintain residual concentration at the actual water temperature.

 Using the formula and above data, in this case 10 g / 0.2 h = 50 g or five times more than without compensation for ozone destruction in water because of half-life.

For more information on system sizing and application information contact our staff.

Phone: 515-635-5854
E-mail:info@oxidationtech.com

Ozone Laundry Facts vs. Fallacy

Over the last twenty years I have witnessed Ozone laundry companies come and go.

I have witnessed outlandish claims from some of these companies, and quite frankly am tired of listening to the outright lies and fallacies that some of these companies are stating.

I would like to look at some of the facts and hope to help our readers make an educated decision about ozone laundry.

Click here for more info on ozone and luanrdy

This month, let’s look at the two major design differences.

Some ozone laundry companies have taken the path of the “fine bubble diffuser” to inject ozone into the wash water, while other have chosen the Direct Venturi Injection as their means of transferring the ozone gas into the water.  There are claims by manufacturers of advantages to both, so we should look at the design criteria of each and pick what is best for your application.

Ozone gas is dissolved into water by utilizing pressure.   It does not take a lot of pressure to start dissolving ozone into water.  In the industry we call the ability to dissolve gas into water “Mass Transfer.”  The efficiency of Mass Transfer of either style of injection device is highly dependant upon the design criteria of the device.

Ozone bubble diffuser

 The idea of the fine bubble diffusion injection method used on washing machines is borrowed from the bottled water industry.  In bottled water plants, ozone in introduced into a large column (or tank) of water.  These are usually in excess of 15 feet tall. Water flows in to the top of the tank and exits the tank through the bottom.  The fine bubble diffuser is placed in the bottom of the tank.  Ozone is introduced thru that diffuser in the bottom of the tank. Water is introduced in to the top of the tank and flows downward, where it exits out the bottom of the tank.  As the ozone bubbles rise, they are violently thrashed around due to the counter flow if the water flowing through the tank.  This turbulence lends for a pretty decent mass transfer of the ozone gas into the water.  The tanks used in the Las Vegas water treatment plant are 32 feet tall.  Remember that pressure is needed to transfer the ozone into the water solution.  Every inch of water column used adds more pressure to the diffuser stone, located in the bottom of the tank.  Therefore the taller the tank, the more pressure created at the bottom of the tank from the weight of the column of water, and the better the mass transfer of the ozone into the water.

ozone contact basin

 Once the un-dissolved ozone reached the top of the tank, it is removed thru an air vent and destroyed by passing thru an ozone destruct system.

All in all, this is a very safe and effective way to dissolve ozone in to water.

However, when the designers of the fine bubble diffusion systems implemented this type of system on a washer extractor,  they left out a couple key ingredients.

Clean mazzei ozone venturi in action
Ozone venturi in action

 First, the column of water in a washer/extractor is nowhere near that of a 32 foot tall water tank.  It is more like 12 inches.  This allows for a much lower Mass Transfer efficiency of the ozone gas.  Several ozone engineers that have studied this design have figured that the efficiency is somewhere in the 25-40% range at best.  That means in the best case scenario, 60% of the ozone gas does not get dissolved.  This is important in that 1% of un-dissolved ozone gas can easily make a room unsafe for the laundry workers.   In the bottled water design, you have the ability to capture this un-dissolved gas and destroy it.  The main problem here is that the designers somehow forgot to include this important piece of the puzzle.  Common sense tells you that if you force air(or Ozone) into an unsealed vessel, air (or Ozone) will escape out the vents of the machine on into the laundry room where it comes into contact with the laundry workers.  Some companies have tried to cover up this major design error by installing an ambient ozone room monitor that in theory shuts off the ozone generators when this level is reached.  In reality, the ozone generator is only on a few seconds before it is shut down due to over saturation of ambient ozone in the room.  Then many times it takes several minutes for the room sensor to reset and let the system turn on the ozone generator again.  I have witnessed the ozone generator being in operation for all of 45 seconds during a 7 minute wash step.  That’s not going to kill many “Super Bugs”.  I recently attended an ozone conference where the guest speaker said that a fine bubble diffusion system on a washer/extractor was “So easy to Build, that even a Caveman could do it”

It is not only that it is easy to build, it is also cheap to build this type of system.  That is why there are so many on the market, and the low price keeps the attention of the potential uninformed buyer.

The Venturi Injection System uses the pressure of the water stream in the piping to create suction.  When applied to this suction port, 85-90% of the ozone gas is instantly dissolved in to the water.  Since we still have this water and un-dissolved gas contained inside the water piping, it can easily be run thru an Ozone Degassing chamber that removes the un-dissolved ozone gas where it can be destroyed.   The end results are 100% dissolved ozonated water going to the washing machine.  This is an over-simplification of the process.  But it should get the point across without going into all the hydraulic engineering facts that make this a much more reliable and stable way to dissolves ozone into water. The disadvantage of the Venturi Injection System is that it costs more to build this type of system.

Another reason not to consider the fine bubble diffusion type of technology is the time it takes to build up to concentration.  Those of you operating commercial laundries know that you never want to fill up a washer with cold water then steam up the temperature to 160 degrees, because it takes too long.  I know there are some cases where this is unavoidable.  But normally you would fill your washer up with your standard hot water usually 130-140 degrees, then add steam injection to raise the temperature in those wash steps where you need a little higher temperature.  The same is true with the fine bubble diffuser.  A Venturi Injection system instantly fills the washer with highly concentrated ozonated water that instantly starts the cleaning and sanitizing process.  It can take as much as 20 minutes for a fine bubble diffusion system to reach the ozone levels where the Venturi Injection system starts.  None of us have that much extra time available in our wash cycle.

Ozone Laundry system
Ozone laundry system showing bubble diffusers and direct venturi injection.

Finally, some Venturi Injection Systems on the market allow for larger than normal fill valves and water lines to be utilized.  This will allow for much faster fill times.  I have witnessed a 60 lb washer/extractor being filled in under 25 seconds, whereas the standard fill time was in excess of 2 minutes.  On a standard hospitality wash cycle with five fills, this would shorten your wash cycle by more than 7 minutes of total operating time.  Washing an average of ten loads per day, this type of ozone laundry system would easily eliminate over one hour of processing per day.

In the graph below, you can see two identical tests that show the concentration of ozone throughout a complete wash cycle.  Notice in the Venturi Injection System, the levels start off high and slowly dissipate before the water is drained in each bath.  You should also notice the effect of PH on each bath in the wash cycle.  During the detergent and bleach steps, the ozone is reduced as it is counteracted by the higher PH from the wash chemistry.  As the detergent and bleach are rinsed out, you can see that the ozone hangs around much longer.

In the fine bubble diffuser, you will notice that the ozone levels never reach above the 0.2 PPM of ozone in the water.  It is also evident that the higher PH makes it hard for the ozone to overcome when using a Fine Bubble Diffuser.

Chart compares bubble diffuser vs venturi in ozone laundry

 

I am not stating that the fine bubble diffusion system does not work, or does not clean laundry, but rather, it is no where as effective as a properly designed Venturi Injection System.  Results will be more consistent with the Venturi Injection System than a comparable Fine Bubble Diffusion System.

 By: Mark E. Moore

Ozone dosage and time required to kill specific bacteria

Short list of ozone levels and contact times required to inactivate specific bacteria.  For information on bacteria not shown, or references contact our staff.

Ozone effect on pathogens

Virus destroyed by ozone

  • Aspergillus Niger (black Mount): Destroyed by 1.5 to 2 mg/1.
  • Bacilius Bacteria: Destroyed by 0.2 mg/1 within 30 seconds
  • Bacilus Anthracis: Causes anthrax in sheep, castle and pigs. A human pathogen. Ozone suspceptible.
  • Clostridium Botulinum Spores: Its toxin paralyzes the central nervous system, being a poison multiplying in food and meals. 0.4 to 0.5 mg/1.
  • Diphtheria Pathogen: Destroyed by 1.5 to 2 mg/1.
  • Eberth Bacilius (typhus abdominals): Destroyed by 1.5 to 2 mg/1
  • Echo Virus 29: This virus most sensitive to ozone. After a contact time of Minute at 1 mg/1 of ozone, 99.999% killed.
  • Escheriachia Coli Bacteria (from feces): Destroyed by 0.2 mg/1 within 30 seconds
  • Encephalomyocarditis Virus: Destroyed to zero level in the less than 30 seconds with 0.1 to 0.8 mg/1
  • Entcrovirus Virus: Destroyed to zero level in the less than 30 seconds with 0.1 to 0.8 mg/1
  • GDVII Virus: Destroyed to zero level in the less than 30 seconds with 0.1 to 0.8 mg/1
  • Herpes Virus: Destroyed to zero level in the less than 30 seconds with 0.1 to 0.8 mg/1
  • Influenza: 0.4 to 0.5 mg/1
  • Klebs- Loffler Virus: Destroyed by 1.5 to 2 mg/1
  • Poliomyelitis Virus: Kill 99.999% with 0.3 to 0.4 mg/1 in 3 to 4 minutes
  • Proteus Bacteria: Very Susceptible
  • Pseudomonal Bacteria: Very Susceptible
  • Rhadbovirus Virus: Destroyed to zero level in the less than 30 seconds with 0.1 to 0.8 mg/1
  • Salmonella Bacteria: Very Susceptible
  • Staphylococci: Destroyed by 1.5 to 2 mg/1
  • Stomatitis Virus: Destroyed to zero level in the less than 30 seconds with 0.1 to 0.8 mg/1
  • Streptococcus Bacteria: Destroyed by 0.2 mg/1 within 30 seconds Test results from The University of New Hampshire 2001

Pathogenic bacteria inactivated with ozone

Ozone Calculations and Conversions

OZONE CALCULATIONS

Below are helpful calculations to determine ozone dosage rates, ozone production and other data.  This is helpful information all in one place to determine system sizing and design for your ozone project.

Click here for definations on common ozone units of measure

 

OZONE DOSAGE RATES INTO WATER FLOWS

(GPM x 3.78 x 60 x ppm) / 1,000 = g/hr ozone

Example = (10 GPM x 3.78 x 60 x 2.0 ppm) / 1,000 = 4.536 g/hr ozone dosage

 

OZONE GENERATOR OUTPUT

((LPM x 60) x 0.001) x g/m3 = g/hr

Example = ((10 LPM x 60) x 0.001) x 10 g/m3 = 6 g/hr ozone production

 

 

OZONE CONCENTRATION IN AIR BY VOLUME

1 mg/l = 1 g/m3 = 1 ug/ml = 467 ppm O3

1 ppm = 2.14 mg/m3 O3

100 pphm (parts per hundred million = 1 ppm (parts per million)

 

OZONE CONCENTRATION IN AIR BY WEIGHT

100 g/m3 = 7.8% O3

1% = 12.8 g/m3 O3

1% = 7,284 ppm O3

 

 

OZONE CONCENTRATION IN OXYGEN BY VOLUME

 

100 g/m3 = 6.99% O3

 

1% = 14.3 g/m3 O3

1% = 6,520 ppm O3

 

OZONE CONCENTRATION IN WATER

1 mg/l = 1 ppm = 1 g/m3 O3 (by weight)

 

 

PHYSICAL PROPERTIES OF OZONE

Density of ozone = 2.14 kg/m3

Molecular weight of ozone = 48

Density of oxygen = 1.43 kg/m3

Molecular weight of oxygen = 32

Density of air = 1.29 kg/m3

Density of water = 1,000 kg/m3

 

 

For help with any of these calculations or for other ozone design information contact our ozone application experts.  We would be glad to help!