Abstract: A thermochemical treatment system for plastic and/or elastomeric waste is described, having three Reaction Units (1), (2) and (3) connected in series, being performed in each Reaction Unit, under positive pressure and low temperature (between 200° C. and 660° C.), one step of the thermochemical treatment process of the plastic and/or elastomeric waste without pretreatment (grinding, washing and drying), through the indirect heating by molten salt coils (5), with the generation of a solid fraction which is continuously drained by an outlet (104); a gas fraction which is treated in a Gas Scrubbing Unit (10) for release into the atmosphere, and a liquid fraction (molten plastic) which is subjected to an endothermic reaction under positive pressure (between 2 and 10 bar) and at temperature above 300° C.