The Raschig ring packing was developed by F. Raschig in 1914. It is one of the earliest invented random packings with a fixed geometric shape. It features a simple structure, with its height equal to its diameter. Larger Raschig rings (above 100 mm) are typically stacked in a structured manner, while those 75 mm and below are usually dumped randomly. Due to its high open area, large void space, high capacity, and low resistance, the Raschig ring allows gas and liquid to flow freely within the packed column. The distribution of gas and liquid within the packing layer is relatively uniform. In particular, the inner surface of the ring is easily wetted by liquid. Regardless of its orientation, liquid sprayed onto the packing flows partly along the outer wall and partly along the inner wall. This increases liquid dispersion and improves the utilization of the inner surface. As a result, it not only offers high capacity and low pressure drop but also enhances the mass transfer and separation efficiency of the column.