With the proposal of “double carbon target”

the pace of low-carbon transformation of power system has been further accelerated. The flue gas waste heat utilization systems have been widely applied in thermal power units. As the core equipment of the flue gas waste heat utilization system

the flue gas cooler has a high failure rate in actual operation due to factors such as limited space in the flue gas layout

high flue dust concentration

and ammonium bisulfate deposition. This not only reduces the recovery of flue gas waste heat

but also increases system resistance

resulting in an increase in fan power consumption and even affecting the unit's load capacity and environmental emission. On the basis of extensive researches on the operation of more than 250 sets of flue gas coolers in the thermal power industry

typical faults commonly found in flue gas coolers

such as leakage

boiler ash deposition

bottom flue ash deposition

and low-temperature flue gas corrosion

are summarized. The causes of the above typical faults and their coupling relationships are analyzed in depth. Moreover

the targeted preventive measures are proposed to provide guidance for transformation and operation/maintenance of flue gas coolers.