Recovery system of waste polyester oligomer using hybrid process of methanolysis reactor and distillation

摘要

PURPOSE: An apparatus and an operation method thereof are provided to produce dimethyl terephthalate(DMT) and ethylene glycol(EG) as raw materials of a polyester from a waste polyester oligomer sludge by using a composite methanolysis-distillation apparatus. The composite apparatus dose not precipitate DMT when distilling. CONSTITUTION: The composite methanolysis-distillation apparatus(20) places a distillation device(22) on a methanolysis device(21) continuously, wherein the distillation device(22) contains a distillation part(5), a liquid dispersing device(7), and a partial condenser(11) and the methanolysis device(21) contains oligomer sludge supply devices(1, 3), methanol supply devices(2, 9), a gas dispersing device(10), and a liquid dispersing device(7). The oligomer sludge reacts with methanol gas in the methanolysis device(21) and the gas phase product disperses and enters the lower part of the distillation device(22) from the upper part of the methanolysis device(21). And condensed liquid phase DMT, EG, and methanol drop to the upper part of the methanolysis device(21) from the lower part of the distillation device(22). Methanol gas is discharged to the upper part of the distillation device(22) and is circulated. The reaction temperature of the methanolysis device is 200-300deg.C and the reaction pressure is 2-5bar.