A system and apparatus for pyrolyzing solid wastes to recover there-from useful hydrocarbon distillates, carbon black, and other potentially commercially valuable by-products. Pyrolysis and distillation may be performed substantially continuously, rather than by batch processing. The pyrolysis unit including a distillation array featuring two or more parallel, heated, conveyors, arranged in alternative switch-backs, through which a feedstock is moved during pyrolysis. The feedstock moves from conveyor to conveyor, and thus may pass through zones of different temperature to optimize the distillation of various constituents from the feedstock. Friction-reducing components, such as rollers, are situated between adjacent pairs of conveyors so that temperature differentials, and the resulting contract or expansion of system components, are accommodated and associated stresses ameliorated.