Process for producing an elastomeric compound comprising at least one elastomeric polymer, at least 10 phr of a silica-based reinforcement filler and at least one silane coupling agent, the process comprising: - providing a batch mixer comprising a mixing chamber, a pair of rotors housed in the mixing chamber and a piston arranged above the rotors and movable to and from the pair of rotors; - feeding said batch mixer with said at least one elastomeric polymer, said silica-based reinforcement filler and said at least one silane coupling agent; - mixing, in said batch mixer and for a first predetermined time interval, said elastomeric polymer, said silica-based reinforcement filler and said silane coupling agent in a manner so as to obtain a batch of an intermediate compound wherein said silica-based reinforcement filler is dispersed in said elastomeric polymer; - completely unloading said batch of intermediate compound from said batch mixer; - providing a twin-screw conical mixer having a mixing chamber provided with an inlet mouth and an outlet mouth, wherein the mixing chamber houses two conical screws, counter-rotating and converging towards the outlet mouth, the twin-screw conical mixer being provided with a door adapted to assume a closed configuration of said outlet mouth and an open configuration of said outlet mouth; - feeding said twin-screw conical mixer with said batch of intermediate compound; - mixing said intermediate compound in said twin-screw conical mixer with said door in said closed configuration of said outlet mouth for a second predetermined time interval and under temperature control, in order to obtain said elastomeric compound; - unloading said elastomeric compound from said outlet mouth of the twin-screw conical mixer with said door arranged in said open configuration, wherein in said unloaded elastomeric compound, an amount of said silane coupling agent has reacted with said silica-based reinforcement filler, said amount being greater than or equal to 50% of the fed silane coupling agent, and wherein at least 50% of said amount of silane coupling agent has reacted with said silica-based reinforcement filler during said step of mixing said intermediate compound in said twin-screw conical mixer with the door in said closed configuration. - providing a batch mixer comprising a mixing chamber, a pair of rotors housed in the mixing chamber and a piston arranged above the rotors and movable to and from the pair of rotors; - feeding said batch mixer with said at least one elastomeric polymer, said silica-based reinforcement filler and said at least one silane coupling agent; - mixing, in said batch mixer and for a first predetermined time interval, said elastomeric polymer, said silica-based reinforcement filler and said silane coupling agent in a manner so as to obtain a batch of an intermediate compound wherein said silica-based reinforcement filler is dispersed in said elastomeric polymer; - completely unloading said batch of intermediate compound from said batch mixer; - providing a twin-screw conical mixer having a mixing chamber provided with an inlet mouth and an outlet mouth, wherein the mixing chamber houses two conical screws, counter-rotating and converging towards the outlet mouth, the twin-screw conical mixer being provided with a door adapted to assume a closed configuration of said outlet mouth and an open configuration of said outlet mouth; - feeding said twin-screw conical mixer with said batch of intermediate compound; - mixing said intermediate compound in said twin-screw conical mixer with said door in said closed configuration of said outlet mouth for a second predetermined time interval and under temperature control, in order to obtain said elastomeric compound; - unloading said elastomeric compound from said outlet mouth of the twin-screw conical mixer with said door arranged in said open configuration, wherein in said unloaded elastomeric compound, an amount of said silane coupling agent has reacted with said silica-based reinforcement filler, said amount being greater than or equal to 50% of the fed silane coupling agent, and wherein at least 50% of said amount of silane coupling agent has reacted with said silica-based reinforcement filler during said step of mixing said intermediate compound in said twin-screw conical mixer with the door in said closed configuration.