A melt polycondensation reactor and its falling film element

Abstract

The invention discloses a melting polycondensation reactor and a falling film element thereof. The molten material slides down along the falling film channel of the falling film element to form a film and undergoes polycondensation reaction. Combined falling film element with concave falling film flow channel. The combined falling film element is installed vertically. The falling film flow channels on the element are arranged in parallel and equipped with film distribution holes. The arrangement of pipe fittings and plates, the size of the falling film flow channels and the arrangement of film distribution holes can be tailored to the melting and polycondensation of each polymer. The reaction is designed; there is a heat medium circulation path inside the pipe fittings of the falling film element to ensure that the reaction material is heated evenly and stably when it moves along the falling film flow channel. The reactor and falling film components have flexible design and processing, low cost, small flow resistance of molten material, no back-mixing dead zone, large film forming area and surface renewal frequency, and can be used for polyethylene terephthalate, polyethylene terephthalate, etc. Efficient melt polycondensation of polymers such as propylene glycol diformate and polybutylene terephthalate.

Description

A melt polycondensation reactor and its falling film element technical field The present invention relates to a kind of melt polycondensation reactor equipment in the production of high viscosity polymer. Background technique The key in the high molecular weight polymer polycondensation production process is the continuous removal of the small molecules produced in the system, to ensure that the reaction continues to proceed positively. The molecular weight of the polymer in the early stage of melt polycondensation is low, and the viscosity of the system is not high. Processes such as heat transfer and mass transfer (removal of small molecules) are not difficult, but high molecular weight usually also means high viscosity, melt shrinkage, etc. The viscosity of the reaction material in the late stage of polymerization shows an order of magnitude change, and the difficulty of removing small molecules increases sharply, so the flow characteristics of the material And m...

AI Technical Summary

Problems solved by technology

Most of the currently disclosed falling film polycondensation reactors are designed and manufactured based on specific process operating conditions or high-viscosity polymer categories. Changing the process operating conditions or high-viscosity polymer categories may cause difficulty in controlling the residence time of reaction materials and the quality of polymer products. Obvious fluctuations and other issues

However, the falling film element, the key internal component of the reactor, has little room for improvement, and some falling film elements have complex structures and difficult processing. The cost of improving the structure of the falling film element during the manufacturing of the reactor is high, and it is difficult to polycondense the polymer in the falling film. The change of melt flow behavior in the process realizes low-cost design adjustment on the basis of the previous structure, which limits the scope of application of the falling film polycondensation reactor in the later stage

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