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Cooling Towers Water Treatment

Basics of Water Treatment for Cooling Towers

Water Treatment for Cooling Towers is critical. Cooling towers are integral pieces of equipment to many businesses today, allowing companies to remove heat from their environments to cool down their buildings and processes. These specialized heat exchangers run on the principles of water-cooling methods.  As a result, they need proper water treatment in order to keep costs low and maintain high cooling efficiencies.

Why Cooling Water Treatment Is Done?

Proper water treatment in your cooling tower system is required to minimize the risk of corrosion, scaling, and microbiological buildup. These issues can reduce plant productivity, cause unplanned downtime, and require costly equipment replacements if conditions get out of control. That’s why everyone who uses a cooling tower needs to treat their water.

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Water Treatment for Cooling Towers

Water Problems and Cooling Inefficiencies

Water Treatment for Cooling towers are subject to various  water-related operating problems. These include:

  • Microbiological deposits
  • Mud and grime
  • Scale deposits
  • Corrosion
  • Foam

Microbiological Deposits and Mud/Grime

A large source of cooling tower fouling, microbiological deposits like fungi and algae can form slimes on the heat transfer surfaces of the tower, leading to significant cooling inefficiencies. These deposits can become so abundant in cooling systems that they obstruct the free flow of water and air, weighing down the structural members of cooling towers and potentially causing them to break. In addition they impact cooling efficiencies increase the energy cost to maintain performance.  Similar issues can occur with any mud or grime that forms within the tower.

Cooling tower algae water treatment

Scale Deposits

Scaling can occur when the concentration of a dissolved substance becomes greater than its solubility in the water. This is especially an issue with materials whose solubility goes down as the temperature rises. Calcium sulfate, calcium phosphate, and other calcium salts commonly cause scale, as well as certain materials at high concentrations, such as silica or silicates. Any scale that forms will impact heat transfer, lowering the cooling efficiencies of the tower and ultimately costing you more to run the tower.


Corrosion is always an issue in any water-handling system where the water contacts  metal. In open, recirculating cooling water systems, the concentration of electrolytes caused by evaporation can increase the corrosiveness of the water. Maintaining a reduced pH value can accelerate corrosion but is a good means to control corrosion depending on the metal.


Though not as common as other cooling tower issues, foam can occur in some systems from the cascading water in the cooling tower. As a result, this can overflow the cooling tower sump or cause the fans to blow foam out of the top of the tower. Foam also concentrates deposit-forming materials, thus increasing system fouling.

Water Treatment for Cooling Towers - What is it?

While specific water treatment programs will vary from one application to the next, typical cooling tower water treatment will cover one or more of the following areas:

  • Treating makeup water
  • Filtration
  • Chemical treatment
  • Side-stream filtration

Treating Makeup Water

Makeup water – the water needed to replace evaporated and leaked water from the cooling tower – often needs to be treated before adding it to the system. Depending on the source water quality, hardness or silica may need removed, as well as adjusting the pH levels of the water. In these situations, water softeners should be employed and the use of automated pH control systems should be utilized to maintain consistent pH’s.

pHReady pH Adjuster


By running your cooling tower water through a filtration system, you can remove suspended particles and certain types of organic matter that can contribute to scaling, corrosion, and foaming. Filtration should be done as a beginning step in the water treatment process since removing suspended solids upstream can help protect ion exchange resins and membranes from fouling downstream.

Chemical Treatment

Chemically treating your water is important in order to balance the chemical properties of the water itself, making it less prone to causing issues. Standard chemical treatments include:

With a full stack of quality chemicals, you can not only mitigate any water-related issues, but also optimize the other stages of your water treatment. We find the best solution for complete treatment is the use of automated feed systems complete with sensing technology to directly relate the chemical addition to the amount required to treat in real time.  In addition, to minimum chemical footprint we only deploy highly concentrated proprietary treatment solutions.  Overall, these result in the most optimal treatment for the lowest cost of service.

Side-Stream Filtration

If you plan on recirculating your cooling tower water throughout your system, side-stream filtration units can help to remove any pollutants that may have entered your tower through drift contamination or process leaks. Side-stream units continuously filter your cooling tower water in small increments to remove suspended solids, organic deposits, and silt particles. As a result, the likelihood of any fouling or biological growth reduces, resulting in both water and energy efficiency gains from less water having to be discharged and less scale formation on any heat transfer surfaces.

The ChemREADY Advantage

With significant experience across every major cooling application, ChemREADY is your go-to partner for water treatment for cooling towers. More than just a supplier, we offer the best chemicals available along with our industry-proven expertise to make sure that your water is treated the right way.

If you want to learn more about how we can help with your cooling tower water treatment, or you’d like to discuss your needs in detail, contact the ChemREADY team today.

Need some expert advice or repair services?  Contact ChemREADY today to schedule your free consultation.