Polyester chips usually refer to polyester raw materials produced by polymerization, which are generally processed into flaky particles of about 4*5*2 mm. The process routes of polyester production include direct esterification (PTA) and transesterification (DMT). PTA process has the advantages of low raw material consumption and short reaction time, and has become the main process and preferred technical route of polyester since 1980s. The uses of polyester now include fibers, various containers, packaging materials, films, films, engineering plastics and other fields.