Treatment Works for Plating Wastes
Containing Toxic Metals and Cyanides
George E. Barnes
Professor of Hydraulic and Sanitary Engineering
Head, Department of Civil Engineering and Engineering Mechanics
Case Institute of Technology
Cleveland, Ohio
This paper describes briefly the processes that have been developed
and works that have been constructed to treat the plating wastes from
Talon, Inc., at Meadville, Pennsylvania, over a period of some seven
years. Starting with simple provision for neutralizing the spent pickling
liquors with lime, improvements were begun in 1940 so as to remove
cyanides and chromium along with other toxic metals such as copper
and nickel. Changes have been made from time to time in method and
in the physical plant for accomplishing these purposes. There is now
under construction at Meadville a new multi-purpose treatment works
for complete treatment of all the wastes designed on the basis of cumulative operating experience. Its fundamental features will be described.
A similar one, somewhat smaller in capacity, has been approved for
Talon's Works No. 3 at Hamden, Connecticut.
Nature and Origin of Wastes
The industrial wastes at Talon result from the manufacture of
metal slide fasteners ("zippers"). In the production of these fasteners,
certain steps are required such as forging, rolling, blanking, forming,
and assembling of wire and fastener components made of copper, nickel,
steel, zinc, aluminum, and zinc die castings. Electroplating may be
required for copper, zinc, bright nickel, black nickel, chrome, oxidized,
and other miscellaneous finishes.
Along with these operations, waste effluents will derive from four
separate sources: (1) acid pickling baths, for descaling and decoloring,
(2) nickel-plating tanks, (3) the mill room, for burring, burnishing,
washing, and cleaning, and (4) cyanides treatment as part of zinc and
copper plating. The ingredients of the waste liquors are potentially
troublesome when in sufficient volume or concentration if carried along
with sewage to the municipal treatment plant or if discharged into the
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