METAL ION REMOVAL FROM FOUNDRY
PROCESS WATER BY COAGULATION
A. Robert Jones, Environmental Coordinator
Central Foundry Division
General Motors Corporation
Danville, Illinois 61832
INTRODUCTION
The General Motors, Central Foundry Division's foundry is located at the southwest
edge of Danville on 1-74. It manufactures malleable and grey iron castings for the automotive industry. The manufacturing processes are cupola melting, sand molding, rough
finishing and annealing to produce castings that are used in the production of intake and
exhaust manifolds, transmission parts and brake parts-for example, master cylinders and
disk brake rotor hubs.
In 1978, the average number of employees on our payroll at Danville was 2250 and the
total 1978 payroll was $51.6 million. We spent $94 million in 1978 on goods purchased
from 700 Danville area suppliers for the Danville Plant. Our annual production is about
335,000 tons of castings.
To produce 1400 tons per day of iron castings, we draw approximately 11 mgd from
the Vermilion River for our process and discharge about 10 mgd from outfall 002. Figure
1 is a schematic of a plant water flow balance study that was performed during three typical
operating days in November 1976. The water has five primary uses: cupola shell cooling,
cupola emission cleaning, slag-sluicing, non-contact machine cooling, and dust collecting.
Each cupola melts about 60 tons per hour of scrap metal and sprue and receives about
eight to ten charges per hour. Each charge contains approximately the amount of materials
shown in Table I. These figures give some background information as to the kinds of raw
materials used, and that is the reason for having included them.
1 „        RIVER MATER  L I
RESERVOIR
DUST COLLECTORS
4.7? MGD
PROCESS WATER
0.2 MGD
NON-CONTACT
COOLING HATER
0.91 MGD
u^?
NON-CONTACT
COOLING WATER
3.98 MGO
CUPOLA
FuME CONTROL
7.4 MGD
OUTFALL 002
10.1 MGD
OUTFALL 003
0.003 MGD
EVAPORATION
1 .56 MGO
DRINKING A COOKING
0.01 MGO
5ZL
SANITARY
0.11   MGD
OUTFALL   001
0.09  MGD
SANITARY  SEWER
0.12  MGO
Figure 1. Schematic of plant water flow.
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