Structured packings have been around since as early as the 1940s. Early structured packings, such as Panapak (15), never became popular. Perhaps these were not marketed aggressively enough, or perhaps they appeared before the detrimental effect of liquid maldistribution on structured packing was appreciated. First-generation structured packings are seldom used nowadays.
The second generation of structured packings began in the late 1950s with high-efficiency wire-mesh packings such as Goodloe®, Hyperfil®, and the Koch-Sulzer® (wire-mesh) packings. Extensive experimentation led by Sulzer provided insight into maldistribution, and the knowledge gained was applied for successful scaleup. By the early 1970s, these packings have made substantial inroads into vacuum distillation, where their low pressure drop per theoretical stage is a major advantage. In these services, they are extensively used today. Their high cost, high sensitivity to solids, and low capacity hindered application of these wire-mesh packings outside vacuum distillation.
The corrugated-sheet packing, first introduced by Sulzer in the late 1970s, started a third generation of structured packings. With a high capacity, lower cost, and lower sensitivity to solids, while still retaining a high efficiency, these corrugated sheet packings became competitive with conventional internals, especially for revamps. The 1980s saw an accelerated rise in popularity of structured packings, to the point of their becoming one of the most popular column internals in use today.
Was this article helpful?