Filtration in Cooling Towers

Cooling tower filtration plays a vital role in maintaining peak efficiency and preventing potential damage as well as system clogging. Cooling towers are designed to manage significant volumes of water and/or air susceptible to the infiltration of particles. These particles settle and accumulate on various heat transfer surfaces within the cooling circuit, diminishing the efficiency of the installation. As a result, the process water delivery temperature rises, decreasing productivity and heightening operational costs.

In this blog, we explore the challenges of cooling tower filtration, innovative technologies, and the transformative benefits that shape the landscape of water treatment.

How do Solid Particles Enter the System?

When it comes to cooling towers, it is vital to understand the entry points of solid particles into the system. Make-up water brings a mix of suspended and dissolved solids, a composition influenced by its source and prior treatment. The external environment introduces airborne particles like dust, pollen, spores, and microorganisms based on the tower’s location. Meanwhile, process water undergoes transformations due to system component degradation, inhibitor and biocide introductions, and application-specific characteristics.

Challenges Facing Cooling Towers

Scaling: This occurs when certain salts lose solubility upon exposure to high temperatures, leading to their precipitation on the heat transfer surfaces within the cooling circuit. This process reduces energy efficiency.

Settled sludge: The accumulation of suspended particles in low-velocity areas, causing obstructions, promoting microbial growth, and extending the frequency and duration of maintenance shutdowns.

Biological proliferation: The deposition of algae, protozoans and bacteria, forming biofilms with low heat transfer rates than many metals. In the case of Legionella Pneumophila, this poses health risks to humans.

Corrosion: The degradation of metal surfaces in the system, leading to increased costs for premature replacement of equipment, unexpected production shutdowns, and a decline in heat transfer efficiency.

Technologies used in the filtration of cooling towers:

Disc Filter: This filtration system, designed for particles sized 5 – 400 μm, utilises technical plastic materials resistant to aggressive water and corrosive environments. It combines centrifugal separation and depth filtration for effective cleaning, minimizing water consumption. With a compact footprint, it offers adaptability to any location.

Screen Filter: Designed for inorganic particles sized 100 – 3,500 μm, this filtration system boasts a multilayer stainless-steel mesh for quality filtration. Constructed with robust steel, it withstands high pressures and temperatures. With efficient self-cleaning through low-water-consumption suction nozzles, it delivers elevated filter flows per unit within a compact footprint.

Media Filter: Tailored for 10 μm inorganic particles, this system ensures quality through in-depth filtration with water flow velocity control. Constructed from resilient stainless steel, it withstands tough working conditions. Optimizing backwash water consumption with a low-density filter bed, the system operates efficiently in a compact design.

Centrifugal Separator: This filtration system targets inorganic particles denser than water, employing a combination of centrifugal and gravitational forces. Engineered with plastic and steel materials, it handles high pressures and temperatures efficiently. With a low flush water consumption through cyclonic separation of water and particles, the system maintains a minimal footprint.

Benefits of Cooling Tower Filtration

Prevents Damage to the Tower and its Components: Filtration protects the tower and its components from debris-related damage. The filter removes any debris or foreign objects that could otherwise clog the tower’s piping or damage its internal mechanisms. A clogged cooling tower can cause numerous problems, including reduced cooling capacity, overheating, and equipment failure. A well-maintained filter can help to avoid these issues and keep the tower running smoothly.

Reduces the Need for Maintenance and Repairs: Cooling tower upkeep is often a complex and costly task. However, by implementing proper filtration techniques, the need for maintenance and repairs can be reduced as well as the amount of algae growth in the tower. By keeping the tower clean and free of debris, algae growth can be minimized, which will lead to improved performance and reduced costs.

Helps to Extend the Life of the Tower: A well-maintained cooling tower can have a lifespan of up to 20 years, but only if it is properly filtered. The main benefit of proper filtration is that it keeps the tower clean, which extends the life of the tower and keeps it running at peak efficiency. Cleaning the tower on a regular basis also helps to ensure that it operates safely and does not produce any harmful emissions.

Saves Money: By filtering out the debris and sediment from the water, you can prevent clogs and blockages that can lead to costly repairs. Additionally, proper filtration can help to improve the performance of your cooling tower by reducing the amount of evaporation. This can save you money on your energy bills by requiring less cooling power to keep your building or facility at a comfortable temperature.


Cooling tower filtration is an important part of maintenance to prevent damage to the tower and its components and extend the tower’s lifespan. Filtration has become vital in the pursuit of sustainable and cost-effective cooling tower management. The array of benefits, from enhancing energy efficiency to financial savings, underscores the crucial role filtration plats in the longevity of the cooling tower systems.