Treatment of Power Laundry Wastewater
Utilizing Powdered Activated Carbon and
Cationic Polyelectrolyte
DANIEL S. LENT, Project Engineer
Military Technology Department
U.S. Army MERDC
Fort Belvoir, Virginia 22060
INTRODUCTION
Field military operations utilize such facilities as latrines, laundries, kitchens, and
shower units, which generate wastewaters. These waters, if not properly treated, pose a
threat to the environment and the health of the field troops. The Sanitary Sciences Division,
USAMERDC, as a part of its basic mission, has been engaged in the studies directed toward
the development of equipment for the treatment of these wastewaters, with planned reuse of
the wastewater for nonconsumptive purposes in the arid or semi-arid areas.
Late in 1971 a study was initiated to determine the feasibility of adopting the field
military water purification equipment for wastewater renovation. Tests on synthetic
wastewaters with standard coagulants such as ferric chloride, limestone, lime and alum
indicated that sludge volume generated in the coagulation process could not be effectively
handled by the upflow coagulation basin (ERDLator). Other disadvantages from the use of
conventional coagulants noted were dissolved salt build-up and system upset caused by
varying wastewater compositions. To circumvent these problems, a process based on
powdered activated carbon and a cationic polyelectrolyte was developed.
Following successful testing of this process with synthetic wastewaters of varied
compositions at Fort Belvoir, Virginia, two field studies were conducted at Camp AP Hill,
Virginia (August 1972 and July 1973) using actual wastewaters generated by field shower,
laundry, and kitchen units (1). Test results indicated that the process was applicable for the
treatment of wastewaters generated in field military operations.
Following this extensive testing program, a 10,000 gallon-per-day prototype unit was
designed and fabricated in an 8' wide by 8' high x 12" long Expandable Shelter Container.
The study at the Sterling Laundry, Washington, D.C., was undertaken to evaluate the
prototype unit's effectiveness in treating commercial (power) laundry wastewaters. The
study was jointly supported by the International Fabricare Institute, representing
approximately 12,000 members of the laundry and dry cleaning industry, and the U.S.
Army Mobility Equipment Research and Development Center (USAMERDC).
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