The Preparation Of A Newly Microencapsulated Biocide And Performance Evaluation

In this article,1-bromo-3-chloro-5,5-dimethyl-2,4-imidazolidinedione(BCDMH) and2,2-dibromo-3-nitrilopropionamide(DBNPA) were composited with a biquaternary ammonium salt to form a microencapsulated biocide by the spray drying method. The microencapsulated particle’s surface was observed by scanning electron microscope(SEM), and the performance stability of the microencapsulated biocide was evaluated via the heterotrophic bacteria detection experiment. This experiment’s reproducibility was also evaluated. Through the orthogonal experiment and single factor optimization experiment, the single-doses’optimal concentration ratio was confirmed and the optimal technological conditions were preliminarily ensured. The synergistic effect, bactericidal broad-spectrum, suitable concentration, functional time, the effect of corrosion and scale inhibitor and its influencing factors were investigated. Compared with other commercial biocides and the bactericidal effect under normal operating conditions of circulating water, the industrial application prospect was analyzed. On this basis, the overall performance of the microencapsulated biocide was actually evaluated using the dynamic imitation system, including monitoring the change of the routine physicochemical indexes, microbiological indicator and corrosion fouling indexes. The result showed that the biocide was microencapsulated well, and the microencapsulated product had more stable bactericidal performance. It had a good synergistic effect between two components. When the concentration of the biocide was20mg/L, the4h bactericidal rate reached more than99.00%. Compared with other commercial ones, the microencapsulated biocide showed a better market competitiveness. This biocide showed a broad-spectrum bactericidal performance which was stable in the condition of cooling water. And the impact on the water quality index is small, at the same time it had a good effect of corrosion and scale inhibitor, which having the potential to become a multifunctional treatment agent.