A pilot plant for the high-temperature pyrolysis of polymers to recycle plastic waste to valuable products was constructed based on the rotating cone reactor (RCR) technology. The RCR used in this pilot plant, termed the continuous RCR ([C]RCR) was an improved version of the bench-scale RCR ([B]RCR) previously used for the pyrolysis of biomass, Polyethene (PE), and Polypropene (PP). The improvements resulted in a higher total alkene yield in the [C]RCR compared to the [B]RCR for the pyrolysis of PE and PP. While the total alkene product yield amounts only to 51 wt % in the [B]RCR for PE, in the [C]RCR it could be increased to 66 wt %, which is comparable to the 65 wt % total alkene yield obtained in a bubbling fluidized bed (BFB) of similar scale. Together with the fact that almost no utilities are required for operation of a RCR, the product spectra obtained make this technology a good alternative to the reactor technologies presently applied in pyrolysis processes. Optimum total alkene yields are obtained at temperatures around 1023 K, as intermediate waxlike compounds are not converted at lower temperatures whereas too much aromatics and methane are formed at higher temperatures. The reactor and BFB temperature in the pilot plant have the largest impact on the product spectrum obtained, while the sand and polymer mass flow rates have a very limited effect. For PP pyrolysis the effect of the aforementioned parameters is more pronounced, because this polymer is more sensitive to thermal degradation.