> There are also technicians and just smart guys.
Please make a thread device (not very energy-consuming and suitable for home use) that could melt used cellophane bags into Lego pieces.

You cannot go to Lego because you are copywriters. Maybe in Peabody. Cellophane can not, because cellulose. Polyethylene can be. That is, as desired as possible, but with some subtleties.
This should be something like an electric vault, which is filled with bags and other garbage, then the sprinkle pen is closed and strapped. Heated, excess polyethylene is squeezed out of the side lattice, cooled, disassembled and extracted from a bunch of parts.
Are there engineers-technologists who made Soviet plastic models for gluing? Will this technology or figures?