Investigation of the effect of phosphonate antiscalants on the reverse osmosis membranes' permeation and desalination performance in mine wastewater treatment process

Contaminants in mine wastewater treatment processes can significantly impact the performance of reverse osmosis (RO) membranes. Antiscalants are commonly applied to the RO process to mitigate the deterioration of membrane permeation efficiency caused by fouling. Therefore, it is essential to gain an understanding of the role played by anti-scaling agents in RO operations. This work investigates the effects of three commonly used phosphonate antiscalants, namely ATMP (aminotris (methylenephosphonic acid)), HEDP (1-hydroxyethylidene-1, 1-bis (phosphonic acid)), and PBTC (2-phosphonobutane-1, 2, 4-tricarboxylic acid), on the permeation and desalination performances of RO membranes. The results showed that the presence of phosphonate antiscalants effectively inhibits interactions between components and between components and RO membranes, thereby enhancing membrane flux levels. However, the inhibitors may interact with the membrane surface and alter its properties, significantly affecting membrane performance. Excessive addition of antiscalants increases membrane contamination and deviates membrane flux from optimal levels. Furthermore, adding phosphonate inhibitors significantly affects the membrane retention efficiency of inorganic salt components and the extent to which the membrane retains organic wastewater components. This work provides insight into the role of phosphonate antiscalants in treating wastewater with soluble silica. It may offer a theoretical foundation for standardizing the use of antiscalants in industrial wastewater.