Energy saving device for circulating fluidized bed boiler

The invention discloses an energy saving device for circulating fluidized bed boilers, belongs to the technical field of circulating fluidized bed boilers, and is used for the energy saving of circulating fluidized bed boilers. The technical problem solved by the invention is that the heat energy of slag discharge is not fully used. The invention provides an energy saving device for circulating fluidized bed boilers. The energy saving device comprises: a slag-cooling water pump (10), a slag cooler (11), a buffering water tank (9), and an air preheater (8); the connections between the above parts are that: a cooling water outlet of the buffering water tank (9) is connected to a water inlet of the slag-cooling water pump (10) through a pipeline; a cooling water outlet of the slag-cooling water pump (10) is connected to a cooling water inlet of the slag cooler (11) through a pipeline; a cooling water outlet of the slag cooler (11) is connected to a cooling water inlet of the air preheater (8) through a pipeline; a cooling water outlet of the air preheater (8) is connected to a cooling water inlet of the buffering water tank (9) through a pipeline.