During the last fifty years, scale inhibition has gone from an art to a science. Scale inhibition has changed from simple pH adjustment to the use of optimized dose of designer polymers from multiple monomers. The water-treatment industry faces many challenges due to the need to conserve water, availability of only low quality water, increasing environmental regulations of the water discharge, and concern for human safety when using acid. Natural materials such as starch, Iignin, tannin, etc., have been replaced with hydrolytically stable organic phosphates and synthetic polymers. Most progress in scale inhibition has come from the use of synergistic mixtures and copolymerizing different functional ities to achieve specific goals. Development of scale inhibitors requires an understanding of the mechanism of crystal growth and its inhibition. This paper discusses the historic perspective of scale inhibition and the development of new inhibitors based on the understanding of the mechanism of crystal growth and the use of powerful tools like molecular modeling to visualize crystal-inhibitor interactions.
Keyword: Scale inhibitors, kinetics, molecular modeling, crystal growth/inhibition mechanism, development steps