摘要:
A horizontal trayed reactor operable to facilitate a chemical reaction in a reaction medium flowing therethrough. The reactor can include a plurality of vertically spaced trays disposed within the horizontally elongated vessel shell. The reaction medium can flow in generally opposite directions on vertically adjacent trays so that the reaction medium flows generally back-and-forth through the reactor.
摘要:
The present invention provides an assembly for use in vertical, gravity flow driven polymerization reactors for combinations of high viscosity, high throughput, and shallow polymer depths. The baffle assembly module of the invention includes a support structure having a plurality of side openings. The side openings allow the escape of vapor liberated from the polymeric melt. The assembly further includes a feed splitter followed by two or more vertically arranged rows of baffle plates with the feed splitter and baffles sequentially positioned in the support structure. The plurality of parallel baffles in a row are angled such that when a polymeric melt contacts a given baffle the polymeric melt moves in a downward direction under the force of gravity. The arrangement of the rows is such that each row (except the lowest row) transfers the polymeric melt to a lower vertically adjacent row until reaching the last row of baffles in the module. According to the vertical arrangement of the components in the baffle assembly module and by stacking additional baffle assembly modules if needed within the reactor, the polymeric melt cascades down the vertical length of the reaction vessel interior. The present invention also provides a polymerization reactor that incorporates the assembly of the invention and a method of increasing the degree of polymerization of a polymer melt by using the assembly of the invention.
摘要:
A process for thermally crystallizing a polyester polymer by introducing pellets into a liquid medium having a temperature of at least 140° C. within a liquid medium zone and crystallizing the submerged pellets at or above the vapor pressure of the liquid medium without increasing the molecular weight of the pellets, and while the pressure on at least a portion of the pellets is equal to or greater than the vapor pressure of the liquid medium, separating at least a portion of said pellets and at least a portion of the liquid medium from each other. The crystallization is desirably conducted in the liquid medium zone without mechanically induced agitation. Optionally, the pellets are formed by an underfluid pelletizer.There is also provided a process for thermally crystallizing solid pellets in a pipe by directing a flow of solid pellets in a liquid medium through a pipe having an aspect ratio L/D of at least 50:1, wherein the solid pellets are crystallized in the pipe at a liquid medium temperature greater than the Tg of the polyester polymer.
摘要:
A process and apparatus for distributing molten thermoplastic material supplied directly from melt polymerization to a plurality of molding machines operating in timed sequence is disclosed. The invention is particularly applicable to transferring molten polyester (normally polyethylene terephthalate or a copolymer thereof) directly from a melt polymerization reactor to injection molding machines for producing molded plastic articles.