Elimination of amino trimethylene phosphonic acid (ATMP) antiscalant in reverse osmosis concentrate using ozone: Anti-precipitation property changes and phosphorus removal. (March 2022)

• Record Type: Journal Article
• Authors: Huang, Nan; Xu, Zi-bin; Wang, Wen-Long; Wang, Qi; Wu, Qian-Yuan; Hu, Hong-Ying
• Is Part Of: Chemosphere. Volume 291:Part 3(2022)
• Publication Date: 2022-03
• Subjects: Antiscalant -- Reverse osmosis concentrate -- Ozone -- Chelation and anti-precipitation -- Phosphorus removal; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2021.133027
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Amino trimethylene phosphonic acid (ATMP) was widely used as an antiscalant in reverse osmosis (RO) systems to prevent membrane scaling, and entered RO concentrate at elevated levels. However, phosphonate antiscalants in RO concentrate might aggravate phosphorus pollution, remobilize heavy metals, and adversely affect the sedimentation treatment of RO concentrate. Ozonation was found an efficient method for ATMP treatment. The ATMP removal efficiencies with 8 mg/L ozone were 100% and 86.5% for ultrapure water and RO concentrate, respectively. The ATMP mineralization efficiency reached 46.5% with 8 mg/L ozone. The rate constant for the reaction between ATMP and ozone was 1.92 × 10 6 M −1 s −1 . Increasing the pH from 3 to 9 decreased the ATMP removal efficiency from 90% to 30.9% but increased the orthophosphate formation to ATMP removal ratio from 0.11 to 0.48. The ATMP intermediates generated with low ozone dosages exhibited moderate chelation and anti-precipitation capacity, and their chelation and anti-precipitation capacity could be further attenuated by increasing the ozone dosage. Ozonation alone enhanced the growth potential for microalgae in RO concentrate because orthophosphate formed. Combining ozonation and coagulation effectively removed 83.0% of the total phosphorus from RO concentrate. The maximum algal density of Scenedesmus sp. LX1 decreased by 78.7% by ozonation and coagulation. Graphical abstract: Image 1 Highlights: Ozonation effectively removed ATMP in RO concentrate. The degradation kinetics of ATMP by ozonation were investigated. pH affected the removal efficiency and ozonation products of ATMP. The chelation and anti-precipitation properties were effectively reduced by ozone. The eutrophication risks of RO concentrate were attenuated by ozone/coagulation.