| 摘要 |
FIELD: polymer production and chemical engineering. SUBSTANCE: low-viscosity precondensate of terephthalic acid and ethylene glycol are subjected to granulation in drop column provided with distributing sprayer in its top section. Drop-shaped granules leaving sprayer are blown in countercurrent manner with hot nitrogen flow after specified free fall distance (~ 5-10 m), which reduces fall velocity and accelerates crystallization. In the upper column part, blowing velocity is 1-3 m/s and, in lower part, 3-7 m/s. Dry and partially crystallized granules issuing from the bottom of column are subjected to solid-phase polycondensation. Sprayer is constructed in the form of disk with a multitude of separate nozzles and heating ducts disposed on inner side. Drop column has nitrogen exhaust means and, in bottom zone, nitrogen supply means. Installation also comprises exhaust pumps, ethylene glycol separator, and nitrogen drying apparatus. EFFECT: enabled manufacture of high-quality dustless granules at lower expenses on equipment and lower power consumption. 14 cl, 2 dwg
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