In order to study the influence of steam extraction location on operation parameters of the coal-fired boiler co-firing steam desiccation sludge

thermal calculation for boiler and thermal system of a 300 MW coal-fired power unit was carried out in this paper

based on the energy conservation equation. Under the load of BMCR

90%THA

75%THA

50%THA and 30%THA

the boiler parameters such as boiler thermal efficiency

coal amount of the unit

coal consumption

flue gas temperature

gas flow and spray water flux were studied when the sludge dried by steam extracted from different positions were blended. The results show that

blending sludge would cause deterioration of boiler main parameters

and the variation range increased with the decrease of unit load and growth in wet sludge treatment capacity. At high load

steam extraction from the fourth-stage extraction point of steam turbine had little effect on coal consumption of the unit. At middle load

steam extraction from the third-stage extraction point of the steam turbine had little effect on coal consumption of the unit. At low load

cold reheat steam pipe could only be selected as extraction point.