Energy-saving five-stage tail gas turbine

The invention provides an energy-saving five-stage tail gas turbine which comprises a casing and a rotating shaft installed in the casing; the casing is provided with static blades; a hub of the rotating shaft is provided with moving blades; the casing is sequentially provided with five stages of static blades in an axial direction; the rotating shaft is sequentially provided with five stages of moving blades in the axial direction; the static blades and the moving blades are sequentially and alternately arranged; the five stages of the static blades are first-stage static blades, second-stagestatic blades, third-stage static blades, fourth-stage static blades and fifth-stage static blades respectively; and the five stages of moving blades are first-stage moving blades, second-stage moving blades, third-stage moving blades, fourth-stage moving blades and fifth-stage moving blades respectively. Compared with a four-stage tail gas turbine, for the energy-saving five-stage tail gas turbine, the efficiency is gre