A PILOT PLANT STUDY TO EVALUATE THE TREATMENT
OF COLLOIDAL WASTEWATER BY PHYSICOCHEMICAL TECHNIQUES
Vincent J. Ciccone, Environmental Engineering Consultant
Office of the Surgeon General
United States Army, Health and Environment Division
Washington, D.C. 20310
Don C. Lindsten, Chemical Engineer
Richard P. Schmitt, Chief
Sanitary Sciences Division
United States Army Mobility Equipment Research and Development Center
Fort Belvoir, Virginia 22060
INTRODUCTION
The treatment of specific wastewaters generated in the manufacture of munitions has
been problematic to design engineers, since reliable design criteria were nonexistant.   To
obtain the information necessary to form a basis for design criteria, and to evaluate the
efficiency of selected water treatment unit processes in purifying these streams, a physical-chemical wastewater treatment pilot plant was designed, fabricated and installed at
the Radford Army Ammunition Plant (RAAP), Radford, Virginia.   Unit processes studied
included mixing, coagulation-flocculation, sedimentation, filtration, carbon adsorption,
sludge concentration and sludge vacuum filtration.
The specific wastewater studied here was that generated in the rectification of spent
alcohols.   It contained a variety of dissolved organics and a significant amount of suspended colloidal nitrocellulose fines.   Laboratory studies, conducted by personnel of
the operating contractor for RAAP (Hercules Incorporated) and reported by Smith and
Dickenson [ 1 ], showed that the colloidal nitrocellulose (NC) fines could be efficiently
precipitated by the addition of lime when aided by a cationic polyelectrolyte.   These
results formed the basis for the treatment train sequence selected in the design of the
pilot plant operation.   The plant and test plan were designed and fabricated by personnel
of the Sanitary Sciences Division (SSD), Laboratory 2000, U.S. Army Mobility Equipment Research and Development Center (USAMERDC), Fort Belvoir, Virginia, erected
and operated by personnel of Hercules Inc.   The period of testing was 4 April through
28 May 1975 on the basis of 3 shifts/day, 5 days/week.   The total period of operation
was 36 days.   The results of this study enabled the investigators to establish criteria for
the design of a full-scale physical-chemical plant for treating the colloidal wastewaters
from alcohol rectification operations.
Funding for this project was provided by the Modernization and Special Technology
Division, Manufacturing Technology Directorate, Picatinny Arsenal.   Under contract to
USAMERDC, Jones, Olson and Associates, Inc., Gainesville, Florida, provided assistance
in the analysis of the collected data and the transformation of appropriate conclusions
into full-scale prototype design parameters.
OBJECTIVES OF THE STUDY
The specific objectives of this study were to:   (a) design, fabricate and install a flow-
through physical-chemical pilot plant at RAAP, capable of effectively removing suspended
colloidal nitrocellulose prior to its transfer to a biological treatment facility planned for
RAAP; and (b) operate the pilot plant to acquire the necessary data base for establishing
criteria for scale-up design.
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