The AquaSPICE project partners have conducted a new study ‘Comparison of cooling tower blowdown and enhanced make up water treatment to minimize cooling water footprint‘. Conducted in the Case Study of Böhlen, it compares two strategies to reduce the water footprint of cooling systems: reusing cooling tower blowdown and enhancing make-up water treatment.
It focuses on industrial systems with cycles of concentration (CoC) greater than 3, where blowdown reuse proves to be the most efficient method. It achieves higher water savings (13%) and lower costs compared to the enhanced make-up treatment. The research involved pilot-scale trials using biologically activated carbon filtration, ultrafiltration, and reverse osmosis.
These methods successfully produced high-quality permeate for reuse, with blowdown treatment reaching 80 μS/cm conductivity and 70 μg/L TOC, while make-up treatment achieved 20 μS/cm conductivity and 60 μg/L TOC. The findings highlight blowdown reuse as a viable, cost-effective solution under conditions of increasing water scarcity, emphasizing its potential in industrial applications.