Steam exhaust energy utilizing system of driving steam turbine of thermal power plant and thermal power unit

The invention provides a steam exhaust energy utilizing system of a driving steam turbine of a thermal power plant and a thermal power unit. The steam exhaust energy utilizing system of the driving steam turbine comprises the driving steam turbine, an air preheater and a fan and also comprises a steam-water heat exchanger and an air-water heat exchanger which are formed into a steam-water-air heat exchange system; primary air and or secondary air of the air preheater inlet are or is heated by the steam exhaust of the driving steam turbine through the steam-water-air heat exchange system. According to the steam exhaust energy utilizing system of the driving steam turbine of the thermal power plant and the thermal power unit, the steam exhaust energy of the driving steam turbine is effectively utilized and accordingly the efficiency of the thermal power plant is improved, meanwhile the coal consumption is reduced, and emissions of pollutants are reduced.