Mixing system for polycondensation

The con­trol of mass and heat trans­fer is cru­cial in poly­mer­iza­tion reac­tors to obtain par­tic­u­lar poly­mer grades as well as high yields. Bulk poly­mer­iza­tions or poly­con­den­sa­tions can be quite com­plex, espe­cial­ly dur­ing the final stage. The rea­son is the rhe­o­log­i­cal behav­ior at con­tin­u­ous­ly ris­ing vis­cos­i­ty. At such high vis­cosi­ties, bar­ri­ers to heat and mass trans­fer deter­mine the yield, mol­e­c­u­lar weight dis­tri­b­u­tion and, thus, prod­uct quality.
Espe­cial­ly for the pro­duc­tion of poly­esters the selec­tion of a suit­able mix­ing sys­tem is very impor­tant. Togeth­er with the rhe­o­log­i­cal com­plex­i­ty, water and gly­col has to be removed con­tin­u­ous­ly by evap­o­ra­tion through the liq­uid sur­face to move the chem­i­cal equi­lib­ri­um towards the desired poly­ester product.
The rea­son for the suc­cess of the Eka­to high-vis­cous poly­ester impeller is that it has been designed for opti­mum heat trans­fer as well as quick blend­ing in a high-vis­cous regime. Togeth­er with this, it shows an axi­al flow pat­tern in the lam­i­nar regime, pro­vid­ing a fre­quent renew­al of the liq­uid sur­face. As a con­se­quence, the best mix­ing con­di­tions for a quick and effi­cient water or gly­col removal are established.