Incineration methods and sewage treatment facilities of sewage sludge

When incineration of dewatered sludge containing sewage at 840 to 900 ° C. in a fluidized incinerator, incineration ash adheres to and accumulates on the inner surface of the exhaust gas flow channel on the outlet side of the incinerator. Prevents clogging, damage, and breakage. In a method for incinerating sewage sludge in which dewatered sludge containing surplus sludge is incinerated by a fluidized incinerator, Na, K, Ca, Mg, Al, and Fe in the dewatered sludge supplied to the fluidized incinerator. The components of the dewatered sludge to be incinerated in the fluidized incinerator are adjusted so that the value of X1 obtained by the expression (1) is 1.0 or more from the respective contents and the P content, and further, in the incinerated ash An incineration method for sewage sludge that collects incineration ash to recycle phosphorus components. X1 = {Na (mol) + K (mol) + Ca (mol? 2) + Mg (mol? 2) + Al (mol? 3) + Fe (mol? 3)} / P (mol? 3)} (1) [Selection] Figure 1