Study Of Non-phosphate Water Treatment Agent And Mechanism Of Corrosion Inhibition And Scale Inhibition

With the increasing environmental problems,the environmental awareness of people strengthened gradually,more and more non-phosphorus water treatment agents had been applied in circulating cooling water system,an agent consisting of sodium tartrate,carboxyalkylthiosuccinic acid?CETSA?,zinc sulfate,polyepoxysuccinic acid?PESA?and acrylic acid-2-acrylamide-2-methylpropane sulfonic?AA/AMPS?as raw materials had been abtained,corrosion inhibition,scale inhibition and dispersion performance had been studied of the composite agent,also the mechanism of corrosion inhibition and scale inhibition.The results are as follows:?1?The development of non-phosphorus water treatment agent,using rotation specimen method to study the concentration on the corrosion inhibition of sodium tartrate and CETSA,through the polarization and EIS curve to study the mechanism of sodium tartrate preliminary;The scale inhibition and dispersion of CETSA,AA/AMPS were investigated by calcium carbonate deposition method and dispersion of iron oxide test.The best corrosion inhibition and scale inhibition performance of composite agents were selected by orthogonal test.The contents of each component in this water treatment were sodium tartrate 8mg/L,CETSA 16mg/L,Zn²⁺ 3mg/L,PESA 6mg/L,AA/AMPS 7mg/L.?2?The mechanism of corrosion inhibition and scale inhibition of non-phosphorus water treatment agent was studied.The corrosion inhibition mechanism of the composite agent was explored by polarization curve,EIS and scanning electron microscopy?SEM?.The result of polarization curve showed that the composite agent is a kind of mixed type corrosion inhibitor mainly suppressed anode polarization,SEM showed a film was formed on the surface of carbon steel coupon,thus preventing corrosion effectively.X ray diffraction?XRD?and scanning electron microscopy?SEM?were used to investigate the scale inhibition mechanism of it.XRD showed that the composite agent reduced the diffraction intensity of the strongest peak significantly and destroyed the integrity of the lattice.The observation of SEM showed that the composite agent had a good lattice distortion,which prevents the normal growth and deposition of calcium carbonate.