Water Treatment and Recirculation Process for Data Center Cooling Water Systems

The heat dissipation load of data center servers is extremely high. The cooling water system is the lifeline that ensures their continuous operation. Poor water quality can lead to condenser scaling, corrosion, and microbial clogging, which in turn severely impacts cooling efficiency and may even cause downtime.

The primary task of cooling water treatment is to prevent scaling. Raw water passes through a sodium ion softener, either in side-stream or full-flow mode, to replace calcium and magnesium ions and reduce hardness. As an alternative, the system can dose antiscalant into the raw water, combined with online conductivity-based blowdown control. At the same time, to avoid corrosion, the system must maintain appropriate alkalinity and corrosion inhibitor concentrations in the water. Closed-loop chilled water systems, on the other hand, use pure water or softened water and circulate it with added corrosion inhibitors.

A side-stream filtration system is indispensable. This system draws a portion of the cooling water and passes it through shallow-bed media filters or high-precision bag filters to remove rust, suspended solids, and biological slime. To prevent the proliferation of Legionella and other microorganisms, the system is typically equipped with UV sterilizers, supplemented by shock or continuous biocide dosing. As water resources become increasingly scarce, more and more data centers are adopting water recirculation technologies. These data centers collect the blowdown water and pass it through ultrafiltration and reverse osmosis systems to produce pure water, which is then returned to the cooling tower. If the RO concentrate cannot be discharged, it will be sent to an evaporation unit, thereby achieving nearly 100% water reuse.

Our data center water treatment solution covers fully automatic water softening equipment, high-efficiency side-stream filtration units, disinfection devices, and membrane-based recovery systems. This solution supports year-round uninterrupted operation, helping to optimize PUE and achieve the intensive use of water resources.