Continuous drier suitable for low-melting point chip and use method thereof

Abstract

The invention discloses a continuous dryer applicable for low melting point slices and the usage of the dryer. The dryer is characterized in that the dryer consists of a compressed air dryer, a molecular sieve drying device, a reducing valve, a dry heater, an inverse column stream mode drying tower, a gate valve, a screw extruder, a pulsed-bed crystallizer (pre-crystallizer), a dust trolley, a butterfly valve, a dust separator, an air filter, a rotary valve, a crystallization heater, a crystallization fan subsidiary pipeline systems. The usage of the continuous dryer has the characteristics that the drying capacity of the system is controlled between 50 to 1800KG / H; the water ratio of the wet slices is controlled equal to or less than 0.5 percent; the water ratio of the dry slices is controlled equal to or less than 0.002 percent (i.e., 20ppm); the duration of the feeding and discharging the slice materials (i.e., the drying duration) is controlled within 2 hours. The invention is especially applicable to low melting point PET slices.

Description

technical field [0001] The invention relates to a continuous dryer suitable for low melting point slices and a method for using the same, belonging to the field of chemical fiber machinery manufacturing and application. Background technique [0002] In the spinning process, in order to avoid the breakage of the polymer macromolecules caused by the high-temperature melting process of the slices containing moisture, resulting in a high rate of spinning end breaks, poor post-processing tensile properties, and low strength of the finished product, so before spinning The moisture content of the chips must be reduced. In addition, it can also improve the crystallinity and softening point of the chips, so as to prevent the chips from sticking to the screw at high temperature due to their low softening point when they enter the screw extruder, resulting in "ring knot" material blocking phenomenon. Therefore, in most cases, the chips must be dried before spinning. [0003] Low melt...

AI Technical Summary

Problems solved by technology

[0006] In the process of synthesizing low-melting point copolyester, a high proportion of the third and fourth components is added, which destroys the regularity of the molecular chain, resulting in poor crystallinity, sticky polymer, and poor fluidity, resulting in cutting of the discharge material. Grain Difficulty

As a result, the crystallization speed of the slices is slow during drying. In addition, due to the low softening point of the copolymer when the slices are dried, the polymer particles are easy to stick together, making it difficult to dry the slices.

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