Process for recycling polyethylene terephthalate determined by intrinsic viscosity of polyethylene terephthalate

A method for producing a first intermediate product, comprising:

• a. providing a feedstock that comprises a first polyester;
• b. contacting the feedstock with a first amount of a first organic compound in a volume section V1 to obtain a first initial mixture, wherein the first amount is in the form of a liquid;
• c. contacting the first polyester with a further organic compound, preferably in a volume section V3, to obtain a further initial mixture;
• d. reducing a weight average molar mass of the first polyester, preferably in the volume section V3, to obtain a first intermediate mixture, wherein the first intermediate mixture comprises
• i. a first intermediate product,
• ii. the further organic compound;
• e. increasing the weight average molar mass of the first intermediate product in the first intermediate mixture, preferably in a volume section V6, to obtain a further intermediate mixture that comprises a further intermediate product;
• wherein the first polyester is transported
• I./in a first direction that is at least partially opposite the direction of gravity when the first polyester has an intrinsic viscosity that is larger than or equal to YIV,1, where YIV,1 is 0.10 dL/g;
• and
• II./in further direction that is at least partially along the direction of gravity when the first polyester has an intrinsic viscosity that is less than or equal to YIV,2, where YIV,2 is 0.09 dL/g.