Recycle of Wastewater From Vehicle Washracks
EDWARD S.K. CHIAN, Assistant Professor
AJAY GUPTA, Research Associate
Department of Civil Engineering
University of Illinois
Urbana, Illinois 61801
INTRODUCTION
The availability of water and municipal and industrial use will have a profound
sociological effect on the near future. Shortages of water in certain parts of this country has
already been hastening wastewater renovation programs. More reuse of available water will
be necessary to meet future needs. The U.S. Environmental Protection Agency views
closed-cycle water use as an ultimate goal for industrial plants to control water pollution
and to conserve water resources.
The Water Quality Bill calls for implementation of the best available technology by
1981 and "zero discharge of pollutants by 1985." Membrane processes, such as reverse
osmosis, ultrafiltration and electrodialysis, represent the most advanced methods available
currently for separating suspended and dissolved solids from water, and have potential to
become an important waste treatment tool in providing "pure" water for reuse.
The objective of this study was to treat the waste stream from washrack operations
with reverse osmosis and ultrafiltration processes, and to reuse the treated water. Also, the
work was conducted to identify the composition of the contaminants in the washrack
wastewater, and to formulate the synthetic waste for evaluating the ability of membrane
processes to remove these contaminants. The results provided a basis for establishing
effluent criteria for reuse and for designing membrane treatment facilities.
METHODS AND MATERIALS
Characterization of Wastewater
In the first phase, samples of wastewater from different washrack installations were
collected and analyzed. The specific objectives of analyzing waste samples were:
a. to determine the types of contaminants and their concentrations present in the
wastewater;
b. to obtain preliminary information regarding the possible unit processes needed
for treatment;
c. to establish the compositions of synthetic wastes for use in laboratory
evaluation of various treatment processes;
d. to establish the quality of the effluent for reuse; and to assess the quality of
effluent for reuse and disposal.
Analytical Procedures
A list of the tests to be performed in characterizing the wastewater under this study is
given as follows:
a. pH
b. Alkalinity
c. Solids
Total solids (volatile and fixed solids)
Dissolved total solids
d. Grease and oils
e. Linear Alkyl Sulfonate (LAS)