Tower type pre-polycondensation reactor

Abstract

The tower type pre-polycondensation reactor comprises a tower body, a material inlet and a material outlet are formed in the top and the bottom of the tower body respectively, a vacuum pipe with a plurality of first vacuum ports is arranged at the central axis in the tower body, and a vacuum pipe outlet is formed in the side wall of the tower body; a plurality of tower trays are arranged between the vacuum pipe and the tower body, baffle plates are arranged on the tower trays, the heights of the baffle plates are gradually increased or decreased from the position close to the tower body to the position far away from the tower body, and the height change directions of the adjacent upper and lower baffle plates are opposite; and each layer of tower tray is provided with a downcomer, and the downcomer is positioned at the lowest baffle plate in each layer. According to the invention, materials are baffled/overflowed back and forth on each layer of tower tray, and liquid film flow can be realized at the overflow port, so that the gas-liquid contact area is increased, and mass transfer evaporation of EG is facilitated; and the materials flow downwards in an annular waterfall manner on the inner sides of odd-numbered layers/the outer sides of even-numbered layers, so that the contact area between the materials and vacuum is quickly updated, the mass transfer efficiency is greatly improved, and the polymerization degree is greatly increased.

Description

technical field [0001] The invention relates to a reactor, in particular to a tower-type pre-polycondensation reactor. Background technique [0002] At present, in the production process of polyethylene terephthalate (PET) and its copolyester polymer materials, it mainly consists of two stages of esterification and polycondensation. The polycondensation process of the existing continuous production device generally consists of three continuous processes: the first precondensation, the second precondensation and the final polycondensation. The main function of the first precondensation and the second precondensation is to remove a large number of small molecules in the ester. Or non-condensable gas, and form an oligomer with a degree of polymerization of 25 to 35, providing a guarantee for the final polycondensation reaction. The traditional five-tank process pre-polycondensation needs to involve two-stage independent reactors. The above system has the disadvantages of long ...

AI Technical Summary

Problems solved by technology

The traditional five-pot process precondensation involves two independent reactors. The above-mentioned system has the disadvantages of long process, many control points, and high operating costs.

In recent years, many companies have successively launched multi-layer prepolymerization tanks with agitation at the bottom, and upflow and downflow prepolymerization towers without agitation, all of which have disadvantages such as high equipment manufacturing costs, high equipment heights, and high operating costs.

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