Chemical Fiber Solvent Extraction Project

A company in Jiangsu is the largest modern chemical fiber and chemical fiber raw material production base in China, and the fourth largest polyester producer in the world.
The full name of aramid is "poly(p-phenylene terephthalamide)" (PPTA). The low-temperature solution polycondensation method using NMP as solvent is the most mature process for synthesizing aramid fiber. In the process of producing aramid, an aqueous solution containing NMP and calcium chloride is produced. Tiei CWL-M Centrifugal Extractor is used to recover the NMP solvent and reduce solvent loss.

Using chloroform to perform countercurrent extraction for the aqueous feed can transfer NMP (more than 99.5%) in the aqueous feed to the chloroform phase, effectively reducing the solvent loss in the aramid production process. At the same time, the recovered NMP solvent can be returned to the front-end aramid production process through distillation and refining.

1. The NMP recovery efficiency of the extraction-distillation method can reach more than 95%.
2. The extraction-distillation method can reduce the steam usage by at least 20% compared with direct distillation.
3. The CWL-M Centrifugal Extractor has a compact structure and good airtightness. It is easier to achieve continuous operation than traditional kettles, and has a better on-site operating environment than the mixer settlers.

Tiei Extraction’s equipment has good performance, high automation and stable operation. It has achieved continuous production, greatly improved efficiency and improved the operating environment.