MIL-HDBK-1005/9A
2.5.9
Metal Plating Operations
2.5.9.1
Separate Collection Systems. Metal plating operations
generate a variety of waste materials, including heavy metals,
cyanides, oil and grease, solvents, degreasers, acids, and
alkalies. Safety and cost-effectiveness of treatment dictate
waste source isolation and separate collection systems for
subsequent treatment or material recovery.
a) Cyanide-Bearing Wastes. Keep separate from acid
wastes to avoid cyanide conversion to toxic hydrogen cyanide
gas.
b) Chrome-Bearing Wastes. Keep separate from cyanide
containing wastes so that hexavalent chrome can be acid reduced
prior to alkaline precipitation with other metal-bearing wastes.
c) Mixed Chemicals. Keep acids and bases isolated
and separate from chrome and cyanide wastes.
2.5.9.2
Volume Reduction. Plating process changes should be
evaluated to minimize the volume of wastewater to be treated.
New or modified plating processes should use still rinses,
dragout rinses, or double or triple countercurrent rinses to
minimize water use and wastewater treatment. Advanced treatment
systems using evaporative techniques with minimal discharge
volume have been successfully used at Navy facilities. Recycle
of rinse water is also possible at certain plating shops. The
extent of plating process modifications and water reuse depends
on the quality of plating required.
2.5.10
Drydocking Facilities
2.5.10.1
Collection Systems.
Refer to MIL-HDBK-1005/8.
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