Papers by Author: Hai Hua Li

Abstract: A quaternary non-phosphorus compound agent was prepared from polyaspartic acid (PASP), aconitic acid-acrylic acid copolymer (AA-AA), sodium gluconate and Zn²⁺. The performances of scale inhibiting and dispersing, corrosion inhibiting and biodegradability of the agent were studied. The results showed that when the formula was 4mg/L PASP , 8mg/L AA-AA, 20mg/L sodium gluconate and 2mg/L Zn²⁺, the corrosion rate was 0.0180 mm/a and the corrosion inhibition rate could reach up to 98.01% and the total concentration was not much high. The dynamic simulation test indicated that the scale inhibition and dispersing performance of the compound agent was excellent. In the complex water system which Cl^- and SO₄^2- contents were high, the corrosion inhibition rate on carbon steel was still above 90%. The quaternary compound agent applied to high hardness and high corrosivity water quality. It was a kind of high efficient environment friendly corrosion inhibitor, which could replace the phosphorous water treatment agents on the market.

Abstract: The sulfo-group-containing itaconic-acid-based polymer (IA/SAS) and the itaconic acid homopolymer (PIA) were synthesized. The molecular structure of itaconic acid, copolymer and homopolymer were determined by IR analysis. The performances of inhibition against CaCO₃ and Ca₃(PO₄)₂ scale of the two polymers were compared by the static scale inhibition experiments. When the dosage exceeded 20 mg/L, both of the inhibition efficiencies against CaCO₃ scale were higher than 90%. IA/SAS had obvious performance of inhibition against Ca₃(PO₄)₂ scale, when the dosage of IA/SAS was 28 mg/L, the scale inhibition efficiency reached 100%. While PIA did not show any effect of inhibiton against Ca₃(PO₄)₂ scale within the test range.

Abstract: Morphology and crystal phase of calcium carbonate, which formed with the presence of Mg²⁺, were characterized by SEM and XRD. The effect of Mg²⁺ on crystallization and crystal phase of calcium carbonate was studied. The results showed that the crystal phase of calcium carbonate were mainly calcite and aragonite and the content of aragonite was higher after adding Mg²⁺ to the blank solution. With the increase of Mg²⁺ concentration, the content of aragonite increased. The calcium carbonate crystals grain became more fine and the content of aragonite was higher by synergistic treatment between Mg²⁺ and magnetic field. There was a strong inhibitory effect on calcite when the concentration of Mg²⁺ was more than 0.50mmol.L-1. The calcite could be transformed into aragonite in the presence of Mg²⁺ in solution.

Abstract: Static and dynamic experiments were used to evaluate scale inhibition performance of polyaspartic acid derivative (PASP-SEA-ASP). The static experiments showed that the PASP-SEA-ASP had good scale inhibition performance and the scale inhibition rate exceeded 80% when the PASP-SEA-ASP was 2 mg•L^-1 and the solution temperature was 40 ^OC. In the dynamic experiments, almost no scale formed on the heat transfer surface and the fouling thermal resistance decreases extraordinarily with PASP-SEA-ASP treatment experiment compared with the experiment without treatment. The PASP-SEA-ASP could be used in industrial cooling water systems.