DESCRIPTION OF AN ADVANCED TREATMENT PLANT TO
RECYCLE WATER AT A CHEMICAL R&D FACILITY
Martin M. Gurvitch, Waste Treatment Supervisor
FMC Corporation
Princeton, New Jersey 08540
INTRODUCTION
In January 1976, an advanced industrial wastewater treatment plant started operation at
FMC's Chemical Research and Development (R&D) Center in Princeton, New Jersey. This
"zero discharge" plant treats chemically-contaminated wastewater discharged from a selected set of research laboratories and pilot plant areas and produces a high quality effluent suitable for recycle.
FMC's R&D Center has a floor space of 26,900 m2 (290,000 ft2) located on a 656,000
m2 (162 acre) site, and houses approximately 620 technical and nontechnical personnel.
The treatment plant is actually part of a pilot plant complex that was recently built at the
Center. Most of the research effort carried out in the pilot facility is directed towards agricultural chemicals; the balance covers organic and inorganic product lines including oxidizing chemicals and numerous organic synthesis programs. Therefore, this pilot plant facility
produces a variety of chemical pollution problems, where fluctuations in type and concentration of contaminants, as well as flow surges, are common occurrences.
The "zero discharge" treatment plant was constructed to provide a utility service by
treating chemically-contaminated wastewater and recycling it to the originating laboratories
and high bays in the pilot facility. Major sources of wastewater that enter the treatment
plant include laboratory sinks, hood drains, high-bay floor water, and kettle and tank washings. Sanitary and industrial systems are not combined; the former goes to an existing, on-
site activated sludge plant for treatment and discharge to a nearby river.
All areas served with recycle water have their sinks and faucets clearly labelled with instructions to personnel that the water is recycled and nonpotable. For safety purposes, a supply of
city water is piped in for eye-wash fountains and safety showers. The primary criteria used to
judge reusability of treated water are total organic carbon (TOC), pH and specific conductance.
As a secondary control, periodic analyses are made for bacteria count and contaminants
covered in the National Standards for Drinking Water.
We decided to build this advanced treatment plant by combining known technology with
flexible processing steps, and have it operate under the constraint of "zero discharge." In
addition, the treatment plant is a useful research tool to study pollution problems associated
with existing manufacturing sites as well as proposed new plants.
TREATMENT PROCESSES
Steps to produce recycle water are shown in Figure 1. Major influent flows are from laboratory operations and are collected in one of three equalization tanks. Batch biological
processes proceed in these tanks, after which the water is clarified. The supernatant is filtered through diatomaceous earth, and then processed by reverse osmosis (RO).   The RO product stream is chlorinated and stored for recycle. A secondary influent, much smaller in
volume and more highly contaminated, comes from pilot plant programs. These streams are
biodegraded on a small rotating biological contactor (RBC) unit and passed through a bed of
activated carbon, before combining with laboratory wastewater in the equalization tanks.
Off-specification water, primarily RO reject, is reduced in volume through evaporation in
a submerged combustion evaporator or incinerator scrubber. Cooling tower blowdown also
discharges to the treatment plant and is treated for recycle or disposed of in the evaporator.
A process description, detailed in Table I, shows plant equipment was designed around a
continuous flow capability of 32 liter/min (8.5 gpm). However, the biological steps are limiting and hold plant capacity down to approximately 9.5 liter/min (2.5 gpm). Treatment
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