POLLUTION CONTROL THROUGH WATER CONSERVATION
AT A GREY IRON FOUNDRY
M. E. McGuire, Environmental Engineer
D. R. Williams, Engineer
Deere and Company
MoUne, Illinois 61265
D. A. Fausch, Adv. Engineering Analyst
John Deere Dubuque Works
Dubuque, Iowa 52001
INTRODUCTION
Deere and Company is the world's leading producer of farm equipment and a major
manufacturer of industrial equipment.    John Deere has had a long-standing commitment
to environmental protection.   In 1957, ten years before the State of Illinois adopted
its first water pollution regulations, Deere and Company established self-regulating
standards governing the discharge of effluents into streams and rivers.    A corporate-wide
environmental program has been instrumental in -attaining compliance with state and
federal pollution standards.    This paper presents just one of a number of projects that
the Company has undertaken to keep its factory operations in compliance with environmental standards.
The John Deere Dubuque Works located north of Dubuque, Iowa on the Mississippi
River is the major John Deere industrial equipment manufacturing facility.    The factory
has nearly four and one-half million square feet of manufacturing area and approximately 8,000 employees producing a wide variety of utility, forestry and construction equipment.   The factory includes a grey iron foundry producing 40,000 tons per year of
finished castings for use at the Dubuque Works and at other John Deere factories.
Problem Definition
A sedimentation pond with ten acres of surface area was constructed in  1974 to
provide for an average of 2,100 gpm of foundry process wastewater prior to discharge
to the Little Maquoketa River.    This pond is shown schematically in Figure  1.    A
National Pollutant Discharge Elimination System (NPDES) permit was issued on December 31, 1974 containing the discharge limitations listed in Table I.   Discharge monitoring
data indicated that the final effluent limitations for zinc and phenol could not be met
with the existing system as shown in Table I.   Zinc levels were well above the 1977
permit limitations and phenol levels exceeded the limits during the winter months.
Zinc enters the foundry operation as an impurity in purchased steel scrap, which is
melted in water-cooled cupolas.    During the melting process the zinc is vaporized and
captured by a wet Venturi scrubber system.   The scrubber system wastewater is then
discharged into the sedimentation pond.
The primary source of phenol is the binding agent used in making cores.   The phenol enters the process wastewater system through the wet dust collectors which operate
in the core knockout department.   During production, all foundry process wastewater is
discharged into the sedimentation pond.
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