59    BIOTREATMENT OF PHARMACEUTICAL WASTEWATER
USING POWDERED ACTIVATED CARBON
TREATMENT PACT® SYSTEM
Hong J. Xu, Contract Environmental Engineer, CPI
John B. Webster, Environmental Engineer/Water Program Manager
The Upjohn Company
Kalamazoo, Michigan 49001
Bruce E. Merchant, Technical Services Manager
Department of Public Utilities
Kalamazoo, Michigan 49007
BACKGROUND INFORMATION
The Upjohn Company chemical operations generate approximately 50,000 gallons of process
wastewater every day. This waste stream contains up to 5% of organic solvents and is currently
discharged from chemical production buildings to a steam stripping process to strip and recover most
of the solvents in the waste stream. Effluent from the steam stripper, where the majority of the
volatile organics have been removed, is mixed with another waste stream containing high levels of
chromium and zinc and injected into onsite deepwells regulated by the Environmental Protection
Agency (EPA) and its Underground Injection and Control (UIC) Program.
Due to the O & M cost and uncertain regulatory future of deep well injection as an aqueous waste
disposal method, a pilot study was conducted in July, 1987 to determine the treatability of the deep
well stream by the Kalamazoo Water Reclamation Plant (KWRP), which operates its plant using
powdered activated carbon treatment technology (PACT®). The final conclusion of that study was
twofold. The first conclusion was that, in terms of the removal of carbonaceous BOD5 (CBOD), the
deep well stream was found to be treatable by the KWRP. The second conclusion, however, was that
the deep well stream was unable to be diverted to the sanitary at that time. The pollutants in the deep
well stream were found to inhibit the nitrifying organisms in the city's secondary treatment process.
In order to address a major fugitive emission concern associated with the historical deep well
operations, the Upjohn Company has recently implemented a steam stripping system to pretreat the
aqueous waste stream (50,000 gallons/day) to remove and recover most of the low boiling point
volatile organic solvents from the waste stream before being injected into the deep wells. The current
injected waste is the combined waste streams of stripper effluent and a heavy metal containing
wastewater. Testing has confirmed that the stripper operation removed significant amounts of volatile
organics from the waste streams.
In light of these promising results, another pilot study was conducted in summer of 1992 to study
the treatability of the steam stripper effluent using the KWRP's existing PACT® system. The operating conditions of the pilot system were chosen to model the current full scale operating conditions at
the KWRP. The chromium containing wastewater was not involved in this study since this is a
regulated discharge to the KWRP based on the pretreatment limits for the constituents. This wastewater is still being injected into the deepwells and will be investigated for alternative pretreatment
methods before requesting approval for discharge to the KWRP.
PILOT STUDY PROCEDURES
Pilot scale studies using PACT® systems are routinely performed to evaluate treatment of and to
accumulate design information for various wastewaters at the KWRP. The major components of
the pilot scale system include a 100 liter stainless steel aeration tank followed by a 1 liter stainless
steel polymer mixing chamber and an approximately 20 liter stainless steel continuous flow clarifier. The aeration tank is divided into four quadrants. The four quadrants in series are used to
produce plug flow movement of mixed liquor through the system. Each quadrant of the aeration
48th Purdue Industrial Waste Conference Proceedings, 1993 Lewis Publishers, Chelsea, Michigan 48118. Printed in
U.S.A.
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