Bottom ash is removed from the boiler and is usually collected by water-cooled
screw or drag chain conveyors. The cooling screw is very effective. It is based on
watercooled jacket and shaft. The screw keeps the ash moving, thus maximising
the cooling effect. The bottom ash itself is not watered. Afterwards it is conveyed
to reuse, usually in the civil engineering or fertilising industry. The sand collected
in the process is fed back to the boiler. Fly ash is handled in an air-tight casing to
keep the dust inside and to avoid burns and other possible safety problems. Fly
ash can be reclaimed from the silo to the truck in either a dry or wet condition.
The wet reclaiming is carried out by ash humidifiers developed by BMH.
Just as all fuel is not equal, ashes are different, too. Even if the basic idea and
purpose remain the same, each ash handling solution needs to be designed and
built exactly to the demands of a particular power plant. BMH has delivered ash
handling solutions to serve the boilers of all major manufacturers..