Waste into treasure: New insight to inhibit scale generation in industrial circulating cooling water

Abstract

The present study investigated the inhibitory role of ginkgo fallen leaves on scale generation in industrial circulating cooling water (ICCW), and the dual scale inhibition mechanism was revealed to demonstrate the ICCW engineering application potential of ginkgo fallen leaves treatment. The results showed that pH, alkalinity and turbidity decreased from 8.68, 295.74 mg/L and 2.482 NTU to 7.27, 111.23 mg/L and 0.483 NTU, respectively, after adding 7.5 g/L fallen leaves in 2 h. The ascorbic acid released by the fallen leaves not only decreased the ICCW alkalinity, but also complexed with the residual Ca2+ to form calcium ascorbate, which combined to inhibit the ICCW scale generation. Finally, compared to other chemical scale inhibition methods, fallen leaves treatment could save 0.34–850 CNY/ton in agent costs. Also, no additional building area was required, saving infrastructure costs. Therefore, turning fallen leaves waste into treasure provided the green and sustainable innovative strategy for scale inhibition in the ICCW, and has significant potential for engineering applications.

Keywords

• Ginkgo fallen leaves
• Alkalinity
• Ca2+ concentration
• Ascorbic acid
• Green development