Compounding Of Non-phosphate Corrosion And Scale Inhibitor And Mechanism Exploration

To meet water saving requirements,industrial circulating cooling water system will face some problems.The most common solution is dosing control.Currently,most of them are low-phosphate formulas,they are still easy to cause eutrophication of ecological environment.Therefore,research and development of non-phosphate formula was of great significance.At the present stage,the pharmaceutical research directions are mostly synthesis and modification,which may cause problems such as high cost,complex production process,and hard to industrialize in a short term.The important method to solve such problems is screening appropriate agents from the existing industrial agents system and compounding with other components to get practical formulas which can put in the production.In this paper,the single agent of the formula was all non-phosphate.Rotary coupon test,calcium carbonate deposition test,dispersed iron oxide test and zinc stabilization test had been adopted to compare agents and determine the components,preliminary and refined orthogonal tests had been used to get the optimal dosing ratio,and combined with the best dosage test to control the cost of the formula.The best non-phosphate formula had been determined as follows:2,4,6-Tri-(6-aminocaproic acid)-1,3,5-triazine 15mg/L,sodium tartrate 14mg/L,poly-epoxy-succinic acid(PESA)7mg/L,acrylic acid-2-acrylamido-2-methylpropane sulfonic acid copolymer(AA/AMPS)8mg/L,zinc sulfate heptahydrate(calculated by Zn2+)3mg/L,1H-Benzotriazole(BTA)lmg/L.Single factor tests showed that the corrosion inhibition performance of the formula had tolerance to the mal water;scale inhibition performance was inhibited in water with high turbidity.Polarization curve showed that the formula was a mixed corrosion inhibitor and mainly used to inhibit the anode reaction.The electrochemical impedance(EIS),X-ray energy spectroscopy(EDS)and scanning electron microscope(SEM)showed that the corrosion behavior of carbon steel was well inhibited in the dosing system,there were no corrosion marks on the surface,and the components of formula were better involved in the formation of the composite film;X-ray diffraction(XRD)showed that the main peak of calcium scale was reduced in the dosing system,indicated that the crystallinity decreased.Combined with SEM,it found that the normal growth trend of calcium carbonate had been destroyed by the formula,which caused the distortion of crystal lattice.