Coal-fired units coupled with biomass power generation can greatly improve the utilization efficiency of biomass and reduce CO_2 emission

which is an important way for coal-fired units to achieve carbon emission reduction in the future. By taking a 300 MW coal-fired unit as the research object

the influence of large-scale direct coupled biomass power generation on coal-fired units was investigated through boiler thermodynamic calibration calculation based on the energy conservation law. The results show that

after coupling with large proportion of biomass

the original heating surface arrangement can basically satisfy the heat exchange demand. The superheater attempering water consumption increases

the boiler thermal efficiency decreases by 0.14～2.69 percentage points

and the CO_2 emission reduces by about 1.212 million tons. The capacity of induced draft fan needs to be expanded

which will have adverse effects on the corrosion of heating surface

denitration system

dust removal system and desulfurization system

so special measures need to be taken to ensure the safe operation of the unit.