Method for recycling filamentary thermoplastics contaminated by undesirable materials

A recycling method applying, to thermoplastic filaments mixed with undesirable materials, the recycling method comprising successively:

• a feed step during which the thermoplastic filaments and the undesirable materials are deposited in packets on a horizontal conveyor belt,
• a spreading step during which the thermoplastic filaments and the undesirable materials are spread horizontally so as to form a layer,
• a horizontal cutting step during which the layer of thermoplastic filaments and undesirable materials is leveled in a direction parallel to the conveyor belt,
• a first cutting step during which the layer of thermoplastic filaments and undesirable materials is cut in a first vertical direction, forming portions;
• a second cutting step during which the portions of layers of thermoplastic filaments and undesirable materials are cut in a second vertical direction orthogonal to the first vertical direction,
• a first aspiration step during which the thermoplastic filaments and the undesirable materials thus cut are aspirated upwards,
• a tearing step during which the thermoplastic filaments and undesirable materials thus aspirated are torn,
• a beating step during which the thermoplastic filaments and the undesirable materials thus torn are beaten,
• a preliminary grinding step during which the thermoplastic filaments and the undesirable materials thus beaten are ground in the form of fibrils of 12 to 15 mm,
• an agglomeration step during which the thermoplastic filaments and the undesirable materials thus ground are compacted in the form of thermoplastic agglomerates, while the undesirable materials and a small part of the non-agglomerated thermoplastic fibrils mix and form fines,
• a grinding step during which the thermoplastic agglomerates and the fines are ground so as to make the size of the agglomerates uniform at approximately 12 mm,
• a separation step during which the thermoplastic agglomerates and the fines thus ground and made uniform are separated by gravimetry, and
• a recovery step during which the thermoplastic agglomerates thus separated from the fines are recovered and constitute the recycled thermoplastic.