Cooling Tower Water Treatment: Key Technologies, Challenges & Best Practices

I. Introduction

1. Importance of Cooling Towers: Core equipment in industrial cooling systems (e.g., power plants, data centers, chemical plants), directly affecting energy efficiency and equipment life.
2. Common Problems: Scaling, corrosion, microbial growth leading to reduced efficiency and increased maintenance costs.
3. Solution: Optimize system performance through advanced water treatment technologies (e.g. self-cleaning filtration, UV sterilization, intelligent monitoring).

II. Cooling tower water treatment core technology

2.1 Principle of water softening technology

 Water softening is the basis of cooling tower circulating water treatment, the core objective is to reduce the concentration of calcium and magnesium ions in the water to prevent scaling. The main technologies include:

• Ion exchange method:

 Use sodium-type resins (such as sulfonic acid-based resins) to adsorb Ca²⁺, Mg²⁺ in the water, while releasing Na⁺ to soften the water quality. When the resin is saturated, it is regenerated by NaCl solution.

• Membrane Separation (Reverse Osmosis/NaFiltration):

 Utilizing the selective permeability properties of semi-permeable membranes, water molecules are made to pass through the membrane layer under high pressure while high valence ions, such as Ca²⁺, Mg²⁺, etc., are retained. Reverse osmosis (RO) can remove more than 90% of dissolved salts and is suitable for high hardness water sources.

• Chemical precipitation method:

 Ca²⁺ generates CaCO₃ precipitation by adding lime (Ca(OH)₂) or sodium carbonate (Na₂CO₃), which is then removed by filtration. Suitable for high alkalinity water quality.

2.2 Scale and corrosion inhibition technology

• Chemical agents: organic phosphonates, polycarboxylates inhibit calcium and magnesium ion scaling; azole compounds protect metal pipelines.
• Physical treatment: such as the physical descaling device of JHKJAC system, which removes scale without chemicals.

2.3 Microbial control

• Traditional method: Chlorine-based biocides are prone to by-products and high cost.
• Innovative solutions: Ultraviolet (UV) technology (e.g. Trojan system) kills Legionella bacteria efficiently and reduces chemical dependency.

2.4. Principles of operation of the filtration system

1.Mechanical filtration

• Shallow sand filtration:

 Homogenized quartz sand (particle size 0.6-1.2 mm) is used to retain suspended solids (SS) through deep filtration with a filtration accuracy of 10-20 μm. The filter layer is restored by air-water scrubbing (3-5 L/(s-m²)) during backwashing.

• Self-cleaning filter:

 Multilayer stainless steel filter (e.g., 50→20→5 μm gradient) with automatic scrubbing mechanism, differential pressure triggered backwashing, water saving 30%.

2. Membrane filtration

• Ultrafiltration (UF):

Hollow fiber membrane (pore size 0.01~0.1 μm) removes colloids, bacteria, differential pressure across the membrane 0.1~0.3 MPa.

• Microfiltration (MF):

sintered titanium membrane (pore size 0.1~1 μm) is used for high turbidity water pretreatment, acid and alkali cleaning resistance.

System design points:

• Circulating water bypass filtration is designed at 5%~10% of total flow rate.
• Backwash water can be recycled to the cooling tower make-up pool

2.5 Self-cleaning and filtration system

• Patented design: e.g. “self-cleaning water treatment device” reduces the loss of filter material and improves the efficiency of backwashing by pulling the filter frame.
• Intelligent monitoring: real-time monitoring of water quality (e.g., conductivity, microbial content), automatically adjusting the frequency of sewage.

III. Industry Application Cases

1. Data Center: Google adopts natural cooling (seawater/canal heat dissipation) combined with UV treatment to reduce energy consumption.

2. Power industry: Chengda Bio-technology's new cooling tower reduces the adhesion of impurities and improves the heat dissipation efficiency through the filler filtration device.

3. Chemical industry: Circulating water softening process (e.g. lime reaction tank) reduces the concentration of calcium ions and reduces the risk of scaling.

IV. Frequently Asked Questions and Solutions

V. Future Trends and Innovations

1. Green Technology: Phosphorus-free pharmaceuticals, biodegradable formulations (in compliance with environmental regulations).
2. Intelligent: AI real-time optimization of water temperature and water quality parameters, such as China Telecom's patent for inverter control.
3. Water-saving design: recycled water softening process to reduce drainage (e.g. lime reaction tank recycling).

VI. Conclusion and Call to Action (CTA)

• Summary: Cooling tower water treatment needs to combine chemical, physical and intelligent technologies to solve the three major challenges of scaling, corrosion and microorganisms.

• Professional Services: For customized solutions (e.g. self-cleaning systems or UV sterilization), contact our team for technical support.