Additionally installing low-pressure economizer in the thermodynamic system of thermal power plants is one of the effective measures to lower the temperature of exhaust flue gas for energy-saving. The energy-saving principle and calculation of low-pressure economizer in thermodynamic system of a home-made 200 MW unit

as well as main characteristics of its operation

and its superiority in aspects of energy-saving and emission-reducing

have been presented. Results of practical calculation show that the additionally installed low-pressure economizer can reduce the temperature of exhaust flue gas by 28℃

saving standard coal by 3.05 g/(kW·h)

having comparatively good energy-saving effect.