Method for preparing polyester spinning melt by removing polyurethane contained in waste polyester textile through alcoholysis of ethylene glycol

The invention relates to a waste polyester high-value circulation reutilization technique, in particular to a method for preparing a polyester spinning melt by removing polyurethane contained in a waste polyester textile through alcoholysis of ethylene glycol. According to the method for preparing the polyester spinning melt by removing the polyurethane contained in the waste polyester textile through the alcoholysis of the ethylene glycol, a waste polyester textile raw material contains the polyurethane, a raw material, in which ethylene glycol with 1% to 8% of the raw material mass is added, is fed to a screw extruder to be blended, melt and extruded, and the melt viscosity of melt from the screw extruder is 0.40 to 0.50 d1/g; and then the material enters a hardening, tempering and viscosity regulation device, and the melt viscosity of the melt body discharged from the hardening, tempering and viscosity regulation device is 0.635 to 0.685 d1/g. Due to an alcoholysis manner, the influences on the viscosity, flowing property, fiber saturation property and drafting property of a polyester melt body, and series problems that vacuum pipes and tubular heat exchangers are easy to block due to the existence of spandex (polyurethane) are reduced.