The issue of water scaling in the treatment of cooling water has become an imperative problem that should be solved urgently for the sake of safe operation in large-scale flexible DC converter stations. However, the coexistence of Ca2+ and Mg2+ in high content in this sort of pending raw water is quite hard to tackle. β-CD-MA-SSS, an eco-friendly ternary co-polymer antiscalant with good performance of inhibiting the formation of scale, was applied to address this conundrum in this paper. The efficacy of the antiscalant β-CD-MA-SSS was investigated in cooling water systems under the conditions of low hardness, low alkalinity, a temperature not exceeding 80 °C, and a pH range of 6–8. After optimization, this reagent dem onstrated an excellent scale inhibition rate up to 80% for both calcium carbonate and calcium-magnesium mixed scales. Scanning electron microscopy (SEM) analysis revealed a noticeable reduction in the size of CaCO3 particles when subjected to the action of β-CD-MA-SSS. It was postulated from FTIR analysis that nanoinpurity and chelation effects mainly contributed to the mixed scale inhibition. Further, the effect of β-CD-MA-SSS on the actual production wastewater was comprehensively evaluated from the technical, economic and environmental aspects.
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