AWT: Monitoring & Partial Softening

Cooling towers create some of the larger potable water loads in commercial office buildings. Up to 50% is regularly flushed or blown down to minimize scale build up.

The National Renewable Energy Laboratory (NREL) tested a supplemental water treatment system that determines the optimal blowdown to satisfy water chemistry limits. Researchers found that the system saved 15% water. View full-size infographic. [PDF - 236 KB]

GPG Findings 045, October 2020, Electrochemical Cooling Tower Water Treatment. Opportunity: How much water do cooling towers routinely blow down? UP TO 50% of Cooling water is flushed To minimize scale build-up. Technology:How do Alternative Water Treatment (AWT) systems work? PARTIAL SOFTENING INCREASES BLOWDOWN SETPOINT. SUPPLEMENTAL TREATMENT SYSTEM DETERMINES OPTIMAL BLOWDOWN TO SATISFY WATER CHEMISTRY TARGETS; SIDESTREAM FILTRATION FILTERS DEBRIS. Real-time monitoring sends system alarms via built-in display or integrated with building management system Measurement and Verification. Where did M and V occur? National renewable energy Laboratory (NREL) assessed a continuous monitoring and partial-water softening system provided by Aqualogix in three cooling towers at the Lloyd D. George Courthouse in Las Vegas, Nevada. Results: How did the monitoring and partial-softening system perform in M&V? 15% WATER SAVINGS, 52% reduction in blowdown, MET GSA WATER STANDARDS, Monitors performance and sends alarms, O&M UNCHANGED, Works alongside traditional chemical treatment, 3 YEAR PAYBACK @ GSA avg. water/sewer $16.76/kgal Deployment: Where does the assessment recommend deploying this AWT system CONSIDER FOR ALL COOLING TOWERS Continues standard and familiar water treatment practices and may offer an easier and more failsafe deployment opportunity for GSA facilities [PDF - 236 KB]


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Last Reviewed: 2022-11-11