degree with the temperature. Numerical values are reported in Table 1, but it is evident that the main increase in degradation occurs by raising the pyrolysis final temperature from 360 to 380 °C, while nearly complete degradation is approached at 420 °C. Visual inspection of the residues of PP and coffee, after reactor opening, showed agglomeration, with the lowest temperature, the most close-grained (toward a single, large, and compact aggregate). Consistently, the polymer behavior during pyrolysis in a vertical fixed bed appears as follows: once melted, it can both degrade and spread uniformly in the solids matrix of coffee and inert sand, soaking it. The higher the pyrolysis final temperature, the greater the degradation progress. At the lowest temperature, the residue consists of a single block of material, whereas at the highest temperature, the