A Wet-bottom furnace or wet-bottom boiler is boiler that contains a wet bottom furnace.
It is a kind of boiler used for pulverised fuel firing.
Wet bottom boiler slag is the molten condition ash as it is drawn from the bottom of the slag-tap or cyclone furnaces.
[1] An advantage is the fact that the end product in this process has a higher value compared to that of a dry bottom boiler.
Wet bottom boilers are preferred for low volatile coals that produce a lot of ash.