WASTEWATER TREATMENT EVALUATION AND REDESIGN
Hugh McLaughlin, Process Engineer
Schenectady Chemicals, Inc.
Schenectady, New York 12301
INTRODUCTION
In 1979 Schenectady Chemicals, Inc. (SCI) initiated a program to review the operation of
its wastewater treatment plant at Rotterdam Junction (RJ). This review was prompted by
the escalating cost of activated carbon used in the wastewater train. Currently over one
million pounds of activated carbon are used each year.
This wastewater review quickly developed a dual purpose to reduce the "cost of carbon"
and to develop a waste treatment strategy that will meet the discharge permit levels of the
1980s. The cost of activated carbon is a problem that should be solved, but this solution
must incorporate the anticipated lower discharge permit levels of the 1980s. Otherwise,
SCI-RJ would again have an unacceptable wastewater treatment program in a very few
years.
This wastewater treatment review involved three phases: a) piloting of certain existing
unit operations and proposed new treatment operations; b) extended observation of current
operations; and c) assembly of a new treatment train design.
BACKGROUND
SCI's Rotterdam Junction Wastewater Treatment Facility treats aqueous effluents from
two SCI manufacturing operations. Currently, the treatment consists of three basic operations equalization, removal of water insolubles and carbon filtration. All the chemical
sewers empty into a lagoon, a 0.5 million-gallon holding tank.
After the lagoon, the wastewater is neutralized and sent to Phase 1 (coagulation, floccu-
lation and sedimentation). Phase I removes water insoiubles-essentially xylol and low-
molecular-weight resins. Phase II currently consists of filtration through activated carbon.
This operation removes all soluble aromatics, specifically phenol. After Phase II, the wastewater is discharged to the Mohawk River. The current train is shown in Figure 1.
COAGULA-'JTS
1
ACTIVATED
CARBON
i
1
WASTt
LAGOON
PHASE   I
PHASE   II
iso;ARCS u.o
HCHC
MeOK
MeOH
0-OK
XYL HIRES INS
i
INSOLUBLES
I
xylene
RESINS
AS   SLUDGE
1
#-OK
1
i
L
us
?OLL'JT
SOJRC
ON
f—'                                     TO  CALCON
KOHAKX
RIVER
Figure I. Schematic of current wastewater treatment system at Rotterdam Junction.
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