To study the influence of blending flue gas dried sludge on operating parameters of the coal-fired boiler

thermal balance and thermal check calculation was carried out for a 300 MW unit

and the effects of sludge-coal co-combustion on such parameters as flue gas extraction ratio

boiler thermal efficiency

coal consumption

flue gas temperature and spray water flux were analyzed

under the load of BMCR

75%THA

50%THA and 30%THA. The results show that

blending sludge will cause deterioration of the boiler main parameters

and the influence degree increased with the decrease of unit load and flue gas extraction temperature. Comprehensively considering the site construction and retrofit costs

low temperature superheater outlet is suggested to be a proper position for flue gas extraction.