Cooling Towers 

The Objective: 
Maintain the highest purity of water with the least amount of water waste and chemical use. Chemical use in cooling towers leads to an ever-increasing TDS, which must be reduced by eliminating water (blow down/bleed off), then refilling with raw/lower TDS water. This is a “vicious cycle” that will never end unless one of the TDS increasing culprits is eliminated or reduced: That being “chemicals”.

The Problem:
Cooling Tower water quality tends to be extremely poor. Cooling Tower traditional treatment is based upon extreme chemical use only. This means that you, the “water treatment professional” has a chance to create an entirely new income base, and aid in environmental integrity & responsibility.

I. Water Quality control is difficult due to:
Evaporation rate 
Environmental contaminates 
Extreme chemical use

II. Chemical Dependence is promoted by an industry that serves and maintains cooling towers.
Most cooling tower manufacturers do nothing about recommending or selling treatment equipment along with the towers. In most cases it’s left up to the end users to set up the treatment method.
The cost of chemicals is lower on the front end than water treatment equipment, but far higher based upon the on going nature of the use. 

III. Water Waste:
It’s not uncommon to see a (IE) 3,000-gallon cooling tower continuously draining and replenishing raw water just to lower TDS. This ever-increasing TDS is contributed to a great degree by the chemicals that are used for treatment.

Not only is there an extreme amount of water being wasted on a daily bases, but the environmental impact from the chemical laden wastewater is deplorable. This chemically laden wastewater will eventually make into our lakes, streams, river, and ground water, and is becoming the subject of more stringent EPA regulations.



  • Bacteria/virus elimination/prevention
  • Organic Build-up elimination/prevention
  • Blow-down reduction/elimination
  • Bleed-off reduction/elimination
  • Improved clarity.
  • Scale reduction.
  • Cooler running temperatures where scale is inhibited or reduced.
  • Reduction or elimination chemicals needed for algae control.

All this with no regularly scheduled maintenance on the ozone unit!



Principle of Operation:

Ozone is injected into the water flow created by a separate circulation pump. This pump pulls the water from the towers sump or basin and sends it to the ozone injection, contact tank, and scale/filtration. Lastly, the treated water returns back to the sump or basin.
    The principle is to treat the water and eliminate/reduce the:
  • Scale forming minerals
  • Organics
  • Harmful microbes.
The clean water is then used to clean the entire sump, basin, pipes, and peripheral equipment.

I.  Ozone Injection:
Ozone is injected it into the side stream flow. Oxidation starts to take place immediately on microbes, organics, bacteria, and virus.

II.  Contact/Mixing Chamber:
A contact tank helps to further the ozone’s ability to oxidize particles allowing them time to react prior to returning to the system. As water flows down the Off Gas Tank, ozonated water rises and mixes any gas in the incoming water.

III.  Filtration, Scale Control, Particle Removal:
Possibly the most important aspect of any water treatment is the removal of the particles that have been oxidized. Without this step, all you have done with the ozone is change the structure of the particles by making them larger, insoluble, &/or heavier. This step is necessary for systems that require scale control, and particulate removal.

We are very careful not to construct too large of an ozone unit to handle the bacteria, scale, and algae.

The problem encountered at this point is corrosion. If you carry too high of an ozone residual to de-scale down line you stand a chance of creating a corrosive situation in the sump and its adjacent equipment.

For this reason we have utilized existing water treatment technology and equipment in conjunction with ozonation. The result is a system that works without high maintenance, dangerous chemicals, or costly corrosion.



How does the maximum service flow rate relate to the total system flow rate?

It doesn't. It relates to the total system gallonage. Our formula is: total gallons / 4-5 (turnovers per day) / 60 = gpm of the side stream system. This equals approx. 0.004 gpm/gal (treatment gpm / system capacity). Therefore, it’s crucial that we know the total water volume rather than the tonnage. Tonnage to gallon capacity varies greatly per tower manufacturer.

What is the ozone dosage in grams/hr or lbs/day?
Each ozonator produces a set ozone production in gr/hr. The S1 = 1.2 gr/hr;    22HD = 2 gr/hr; 32HD = 3 gr/hr; 62HD = 6 gr/hr; etc. We convert the measurement to lbs/day when over 24 gr/hr. The typical dosage is: 1 gr/hr to every 5 gpm of treated water.
IE: 10 gpm side-stream ozone treatment system would include a  2 gr/hr ozonator (22HD).

Is the ozone flow controlled by the amount of residual in the system or is it wired to the tower pump or system pump control box?
We supply a timer/control box assembly that controls the ozone unit and circulation pump. Operational time will depend upon water and tower conditions. As the conditions improve the operational time can be reduced.

Does the ozone system eliminate the scaling?
Yes, we can design the ozone system to eliminate hardness/scale that can build-up on the tower, piping, pumps, and peripheral equipment. We us a combination of ozone + water softening to eliminate the scaling. This affords a lower cost system by using a smaller ozone unit. Our system is set so the water is not completely soft and will not be corrosive.

Does the ozone system control algae?
Yes, we can design the ozone system to eliminate algae but this denotes a larger ozonator. Algae are plants with roots and are quite resistant to ozone. We can use ozone only, or ozone + a slight chlorine or bromine residual to eliminate algae. The ozone + chlorine or bromine option affords a much lower priced system since the ozone unit used will be much smaller.

Is it true that ozone systems create a corrosive condition?
In the “old days” when ozone was first used on towers corrosion became an issue. This was due to the over use of ozone, or the excessive dosage injected. There are some companies that are still convinced that more is better and ozone can do “everything”. This can lead to costly corrosion problems.

Our philosophy is to use the ozone where it is best suited:

  • Organic inactivation
  • Bacteria, virus, microbe elimination/reduction
  • Clarifying
  • Odor control
For scale and algae control we utilize tried-n-true water treatment equipment that has been successful in all phases of the water treatment industry for over 50 yrs. This affords the use of smaller and less expensive ozone equipment and avoids corrosive conditions.

Ozone Pure Water

512-259-7575
1-800-633-8469
tecsales@ozonepurewater.com

410 Municipal Drive
Bldg. B Suite 100
Leander, Texas 78641