1. Distillation tower: Due to the presence of formic acid in the materials of trimeric formaldehyde and formaldehyde distillation towers, they have strong corrosiveness. In the past, corrosion occurred when using aluminum titanium float valve trays, especially when starting or stopping. A new tower is usually damaged around half a year, and the floating valve inside the tower reduces weight by 50% within half a year, significantly reducing separation efficiency and seriously affecting production. Replacing it once a year can result in high investment and increased production costs. After using ceramic corrugated packing with a diameter of 800mm, the operation is normal, the efficiency is improved, the reflux ratio is reduced, the formaldehyde and formaldehyde content at the tower top are reduced, and the steam consumption is reduced. There is no corrosion problem when using ceramic corrugated fillers.

2. Distillation tower: In the continuous distillation tower device for separating isomers of chlorinated toluene with an annual output of 1000 tons of para (ortho) chlorotoluene, both the light and heavy removal towers use ceramic corrugated packing to achieve good results. The diameter of the light removal tower is 355mm, and the top pressure of the tower is 40kPa (300mm Hg). After using ceramic corrugated packing, water and about a large portion of methyl benzene light components are completely removed. The bottom discharge of the tower contains about 0.01% toluene, and the packing is resistant to medium corrosion and has good separation effect. The diameter of the weight removal tower is 500mm, and the top pressure of the tower is 26.7kPa (200mmHg). Ceramic corrugated packing is also used to prevent medium corrosion. The majority of high boiling substances are removed from the discharged materials at the bottom of the tower (the materials at the bottom of the tower contain 47% of high boiling substances and about 38.7% of chlorine). The semi-finished products from tower top distillation contain about 0.2% chlorobenzene in the logistics, ensuring that both o-chlorotoluene and p-chlorotoluene products will reach over 98% in the future.