From the collecting conveyor the ashes are transported to a pneumatic conveying system. In the event of an incident, the ash can be diverted to an emergency ash container. On the pneumatic conveying path the ashes of both conveying lines are transported to a boiler ash silo. There are two additional silos for ash residues. Under each silo there are slide valves and rotary feeders to feed and dose the ash onto a downstream collecting conveyor (troughed chain conveyor). Depending on which rotary feeders are in operation, boiler ash or ash residue or a mixture of both can be transported. Depending on the pre-selection, the operator can choose whether to load the ash or mixture directly into a silo vehicle or to feed it into a moistening screw which reduces the dust formation for further transport.