Testing the formation of Ca-phosphonate precipitates and evaluating the anionic polymers as Ca-phosphonate precipitates and CaCO_3 scale inhibitor in simulated cooling water

摘要

The inhibition performance of different phosphonates as CaCO_3 scale inhibitors in simulated cooling water was evaluated. Based on experimental data, various phosphonates form weakly soluble Ca-phosphonate precipitates, with the order of the phosphonates in terms of Ca~(2+) tolerance being BHMTPMP>PAPEMPHDTMPPBTCA>DTPMP>EDTMP>ATMP>HEDP. Homo-, co-, and ter-poly-mers were also investigated for their performance as Ca-phosphonate inhibitors, the order of inhibit Ca-phosphonate precipitation: terpolymer > copolymer > homopolymer. Addition of polymers as inhibitors with phosphonates could reduce Ca-phosphonate precipitation and enhance the inhibition efficiency for CaCO_3 scale. Moreover, polymer composition and concentration are critical to the inhibitory performance.