A process for the producton of pure syngas (hydrogen and carbon dioxide) by fast gasification of liquid, muddy, or solid raw materials, either produced for the purpose or from industrial processes in which they can not be recycled, or fuels from wastes or biomass, which process is carried out in a modular reactor including a raw materials feeding area, a gasification area, a discharging area of the residues in powdery or vitrified form. The obtained syngas is sent to a purification and compression step.