Quick Summary
To reduce reliance on potable municipal drinking water, data center operators in water-constrained regions are increasingly evaluating reclaimed water, treated municipal effluent, and recycled water for evaporative cooling systems. While utilizing alternative water sources supports watershed conservation goals, it introduces operational challenges, including fluctuating suspended-solid loads and elevated background salinity.
Physical side-stream filtration does not remove dissolved salts or alter dissolved water chemistry. However, it plays a critical role by continuously removing suspended particulates, silt, and organic matter down to 55 microns. Implementing filtration systems built with corrosion-resistant polymeric construction, such as Amiad’s DATA Klin, helps protect filtration equipment in aggressive water environments while supporting broader chemical scale- and corrosion-inhibition programs.
What You Will Learn:
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The Transition to Alternative and Reclaimed Water in Cooling Loops
The ongoing expansion of high-density computing and artificial intelligence (AI) infrastructure continues to increase thermal heat loads on facility cooling systems. In water-constrained regions across North America, local utilities and communities are increasingly encouraging industrial facilities to reduce their draw on fresh potable drinking water and groundwater supplies.
To maintain the thermodynamic efficiency of evaporative cooling towers while reducing potable water consumption, facilities are adopting alternative water sources, such as treated municipal effluent (reclaimed or recycled water).
In jurisdictions with established water-reuse frameworks, such as California Title 22, regulatory standards define water quality criteria for industrial and commercial cooling-tower applications. Similar water-recycling practices are being deployed across other drought-impacted regions. However, switching from potable water to reclaimed water alters the incoming water quality profile, requiring specialized equipment selection and water-management practices.
Water Quality Dynamics: Suspended Solids (TSS) vs. Dissolved Chemistry (TDS)
When managing cooling loops utilizing reclaimed water, facility engineers must distinguish clearly between suspended particulate matter and dissolved chemical constituents:
- Dissolved Chemistry (TDS): Reclaimed effluent typically carries higher concentrations of dissolved mineral ions, total dissolved solids (TDS), silica, and chlorides than potable municipal water. Managing dissolved scaling ions and controlling corrosion rates requires an integrated chemical treatment program, including scale inhibitors, corrosion inhibitors, biocides, and controlled blowdown. Physical filtration systems do not remove dissolved salts, chlorides, or chemical ions.
- Suspended Solids (TSS): Reclaimed water can carry variable loads of suspended solids, such as pipe debris, silt, atmospheric dust scrubbed by cooling towers, and microscopic organic particulates.
If unmanaged, suspended solids accumulate in cooling tower basins and settle across downstream plate heat exchangers. Settled particulate layers can create localized stagnant zones that promote under-deposit corrosion and support biological growth [5].
Corrosion Considerations in Reclaimed Water Cooling Loops
Reclaimed water loops often operate under more challenging chemical conditions than potable water systems. The presence of chlorides and elevated conductivity, combined with biocides used for biological control, can increase corrosion stress on metallic surfaces.
Conventional metallic filter housings exposed to high-chloride water may experience localized pitting and corrosion over time. Corrosion and scale buildup on internal housing walls can increase maintenance frequency and shorten equipment service life.
To address these conditions, equipment material selection is an important engineering consideration. Utilizing filtration hardware manufactured with corrosion-resistant polymeric materials provides durability and helps mitigate corrosion risks associated with metallic housings in high-salinity water loops.
The Role of Side-Stream Disc Filtration (DATA Klin)
Physical side-stream filtration serves as a mechanical barrier within an integrated data center water-management strategy. Rather than filtering the entire facility cooling flow, a side-stream system continuously diverts a portion of the circulating water. Side-stream filtration systems are generally sized to filter 3% to 10% (up to 20%) of the overall system flow.
Amiad’s DATA Klin series, powered by Spin Klin™ NOVA polymeric disc technology, is engineered to support cooling towers operating with alternative water sources:
- Polymeric, Corrosion-Resistant Construction: Built with advanced polymeric materials, the filtration system provides high corrosion resistance for demanding cooling-water environments.
- Three-Dimensional Depth Filtration: Spin Klin™ NOVA discs are diagonally grooved on both sides. When compressed, they create a 3D depth-filtration matrix that captures both inorganic particulates and lightweight organic matter down to 55 microns as standard.
- Support for Chemical Water Treatment: By continuously reducing suspended solids, the filtration system lowers particulate accumulation in the cooling loop. Cleaner circulating water helps chemical treatment programs operate under lower particulate loading.
- Low-Volume Backwash Cycle: The automatic self-cleaning cycle initiates based on differential pressure and completes in seconds with minimal water loss, supporting the facility’s Water Usage Effectiveness (WUE) goals.
Water Quality Parameters and the Role of Treatment
Managing alternative water sources effectively requires pairing mechanical filtration with chemical water treatment:
- Suspended Solids (TSS) Management: Suspended particulates create physical fouling risks and contribute to basin silt accumulation. Automatic side-stream disc filtration continuously removes particles down to 55 microns, while chemical dispersants help prevent ultra-fine particles from agglomerating.
- Dissolved Minerals & Chlorides Management: Elevated dissolved salts and chlorides increase the risk of mineral scaling and corrosion on metallic surfaces. Chemical scale inhibitors and managed blowdown cycles control mineral saturation, while polymeric filter construction protects the filtration equipment from corrosion. Physical filtration does not remove dissolved mineral ions.
- Organic & Biological Matter Management: Nutrients in reclaimed water can support biological growth and biofilm development. Physical disc filtration continuously captures algae, organic debris, and suspended biological matter throughout the depth of the disc stack, while biocides provide active microbiological control in the bulk water.
Parallel Industrial Applications in Corrosive and Water-Reuse Loops
Amiad’s filtration technologies have been deployed across demanding industrial water-reuse and corrosive cooling environments worldwide.
Note: These parallel industrial applications demonstrate relevant filtration principles in water-reuse and corrosive cooling environments; they are not data center installations.
Wastewater Treatment Facility Water Reuse (Maryland, USA)
In a wastewater reclaim/reuse application in Maryland, USA, the facility installed an Amiad filtration system consisting of two EBS 10000 automatic screen filters. The project demonstrates the use of automatic filtration in a large-scale wastewater reuse application where suspended solids must be controlled to support reliable downstream operation.
Seawater Cooling Filtration in a Power Generation Facility (Chile)
A large thermoelectric power plant in Chile operated its cooling circuit using raw seawater, an aggressive, high-salinity environment. Existing metallic screen filters experienced severe corrosion and frequent operational issues. The facility replaced the metallic systems with an Amiad Spin Klin™ Galaxy polymeric disc filtration system operating at 100 microns. The polymeric disc system provided continuous depth filtration while resisting the corrosive effects of seawater, demonstrating the durability of polymer construction in demanding cooling environments.
Conclusion
As data centers in water-constrained regions evaluate reclaimed and recycled water to reduce potable water consumption, facility designs must balance sustainability objectives with asset protection.
Reclaimed water introduces higher suspended solids and salinity challenges. While physical filtration cannot alter dissolved water chemistry, implementing automated, corrosion-resistant polymeric side-stream filtration helps control suspended particulates, protects cooling-tower basins from sediment buildup, and supports broader chemical water-treatment programs .
FAQ About Reclaimed Water in Data Center Cooling
Does physical disc filtration remove dissolved chlorides or salts from reclaimed water?
No. Physical filtration systems, including disc and screen technologies, capture suspended solids, silt, and organic matter. They do not remove dissolved ions, chlorides, or salinity. Managing dissolved solids requires chemical corrosion inhibitors, controlled blowdown cycles, or membrane desalination processes such as reverse osmosis.
Why is polymeric construction advantageous for reclaimed water filtration systems?
Reclaimed water typically contains higher concentrations of chlorides, dissolved minerals, and chemical biocides than potable water, which can accelerate corrosion in metallic filter housings. Polymeric construction, such as that used in Amiad’s DATA Klin, is highly corrosion-resistant, providing structural durability across aggressive water chemistries without rusting.
What is the primary role of side-stream filtration in a reclaimed water cooling loop?
In a cooling loop using reclaimed water, side-stream filtration continuously treats a portion of the circulating flow. Side-stream filtration systems are generally sized to filter 3% to 10% (up to 20%) of the overall system flow. By continuously capturing suspended solids, filtration helps prevent sediment accumulation in cooling-tower basins, reduces particulate fouling on heat-transfer surfaces, and supports the performance of chemical water-treatment programs.
