184.108.40.206 Fly Ash. Details of fly ash handling, intermediate storage, and conditioning
are covered in Section 10, Ash Handling, of this design manual. If not sold to an
outside party such as cement or concrete block manufacturers, fly ash can be disposed of
as a solid waste in a landfill. Details of solid waste disposal can be found in NAVFAC
DM-5.10, Solid Waste Disposal. Additional information on solid waste management can be
found in NAVFAC MO-213, Solid Waste Management.
220.127.116.11 Bottom Ash. Bottom ash handling and intermediate storage are discussed in
Section 10, Ash Handling, of this design manual. This waste product is generally
disposed of in either settling ponds or a landfill. The choice of which to use depends
on economics, space availability, and compatibility with the bottom ash removal system.
For example, if the bottom ash is removed dry (i.e., mechanically) the preferred
disposal method is a landfill. However, if the waste is hydraulically removed and plant
space is available, a bottom ash pond may be preferred. If space is limited, the bottom
ash could be dewatered and then landfilled. Consideration of these factors and others
in a detailed study is recommended before deciding on a specific disposal system.
Additional information on solid waste disposal and its management can be found in NAVFAC
DM-5.10 and NAVFAC MO-213.
18.104.22.168 Pulverizer Rejects. In most cases, the pulverizer rejects are transferred
either hydraulically, mechanically, or pneumatically to the bottom ash handling system.
The combined waste product is then disposed of as discussed in Bottom Ash above.
22.214.171.124 SO2 Scrubber Solids. Treatment and disposal of this waste product can be the
most complicated and expensive of the four discussed. To choose a method, consideration
must be given to the type of scrubber system employed, chemical composition of waste
product, and availability of disposal space. A discussion of various waste products
from FGD systems can be found in MIL-HDBK-1003/6, along with information on alternative
disposal methods for scrubber waste products. Additional discussions of FGD waste can
be found in TM-5-815-1/AFR 19-6.
Hazardous Waste Considerations.
(EPA) has interpreted the fossil fuel combustion waste exemption from hazardous
classification to extend to other wastes that are produced in conjunction with the
combustion of fossil fuel, are necessarily associated with the production of energy, and
are mixed with and co-disposed or co-treated with fly ash, bottom ash, or FGD wastes.
Wastes which the EPA has specifically indicated would fall under this co-disposal/co-
treatment interpretation include (but are not limited to) boiler cleaning solutions,
boiler blowdown, demineralization regenerant, pyrites, and cooling tower blowdown.
Therefore, the production of hazardous waste from a fossil-fueled steam power plant
should be prevented through proper design choices.