In the domestic large circulating fluidized bed boilers designed with side wall and back wall coal feeding system

there are generally prominent problems of coal feeding delay and uneven coal feeding in the actual operation process. By analyzing the coal feeding delay problem of large CFB boiler units and the operation characteristics of the existing coal feeding system

the quantitative calculation method of coal feeding delay problem of large CFB boiler coal feeding line is put forward. Based on the case of a supercritical 600 MW CFB boiler coal feed line

the coal feed delay characteristics of the coal feed line under the condition of wide load and rapid peak regulation are obtained. The calculation results show that the coal feed delay problem is common in the variable load operation process of large CFB boiler units

which will lead to a certain degree of uneven coal feed. The variable load range

variable load rate and the number of coal feed ports on the single feed line are positively correlated with the severity of the delay problem. The calculation method and analysis results can provide design basis and technical reference for large CFB boiler coal feed line to adapt to wide load and fast peaking operation.