Operating Costs of
Waste Treatment in General Motors
ROBERT J. BRINK, Works Engineer
Buick Motor Division
General Motors Corporation
Flint, Michigan
In discussing the operating costs relative to industrial wastes, it should be
understood that there are necessarily several broad classifications of wastes. A
general classification would include the chemical, food, mineral and manufacturing industries. In any of these industries, the cost of treatment per thousand
gals will be very different.
In the automobile industry the same type of breakdown occurs. Depending
on the particular plant there may be oil wastes, paint, plating, foundry or more
probably a combination of wastes. Each disposal unit has a peculiar treatment
problem.
The handling of sludge is very important in the cost analyzation picture.
Some plants are able to utilize the sanitary sewers, while others will use lagoons,
incinerate, dewater and dump, dewater and incinerate, or employ biological
reduction. All of these methods generally depend on the requirements of a particular locality and the quantity and type of sludge involved.
There are always many new formulations in the products which the manufacturing operations are utilizing to maintain production standards and to produce a
quality product. Many of these are used with little regard for the cost of disposal
or disposability of the material until it reaches the water treatment facility.
Another factor which we find lends itself forcefully to the cost of disposal are
the side effects from the citizens of the plant community. It stems from the fact
that for every major problem of pollution that you correct several smallerprob-
lems of major importance will be uncovered. For example, an oil slick may have
been on a river for years, but as soon as it is eliminated a rainbow of oil becomes
noticeable to every passerby. This is as it should be, everyone becoming pollution conscious, but all of these factors add to the complex problem of defining
operation costs in general terms rather than to the particular disposal plant.
The only available figures on the cost of operating a disposal system in General Motors are at Buick, which has GM's most completely integrated facility in
the manufacture of automobiles. Here you have forging, foundry, machining,
plating, heat treating, and assembly operations. In our waste treatment we are
faced with many facets of disposal from practically every liquid waste that can be
generated in a metal working industry to the final, costly disposal of the sludge
we generate.
At Buick we treat a mixed waste of soluble oil, insoluble oil, alkalies, paint,
thinners, chrome, cyanide, power house blow down, and washer dumps.
The chrome varies from zero to 5 ppm. The cyanide from zero to 10 ppm.
The soluble oil from 100 to 5, 000 ppm. These wastes must, because of the variation in concentration, be treated batch wise.
It should be noted that in a plant operating on a flow-through basis that the
labor  cost will  be  reduced.     However,   more  controls  are required.    We use
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