Activated Sludge and Alum Coagulation Treatment
of Textile Wastewaters
THOMAS L. RINKER, Environmental Engineer
Blue Ridge-Winkler Textiles,
Division of Lehigh Valley Industries, Inc.
Bangor, Pennsylvania 18013
THOMAS N. SARGENT, Sanitary Engineer
United States Environmental Protection Agency
Southeast Environmental Research Laboratory
Athens, Georgia 30601
INTRODUCTION
Wastewater treatment practice for the textile industry has been concerned almost
exclusively with the removal of degradable organic material by biological treatment
processes. Considering, however, the changing nature of textile wastewaters, considerable
work was needed to demonstrate through long term projects the efficiency of other
available treatment methods. The most critical need was to evaluate those processes which
could be added to an activated sludge treatment system already in existence in order to
minimize capital requirements while providing for removal of additional contaminants.
Historically, most of the reported data for textile wastewater treatment concerned
effluents from textile plants producing primarily natural fabrics. Clearly there was a need
for data from a mill producing widely used synthetic fabrics in order to better characterize
this particular type of wastewater. In order for such single plant information to be effective
in promoting the level of knowledge in this industry segment, wastewater characteristics
would need to be correlated with definitive production data.
Blue Ridge-Winkler Textiles (BRW) was faced in the late 1960's with meeting new,
strict discharge criteria imposed by the Commonwealth of Pennsylvania's Department of
Environmental Resources, and a research program to evaluate alternate treatment
processes was begun by the company in 1969.
Based on the performance characteristics of the then available and demonstrated
technology, BRW decided to use a system composed of an activated sludge process and an
alum coagulation process operating in series. This system would result in the removal of
degradable organics and some nutrients by biological oxidation in the activated sludge
process, and in the removal of metals, colloidal organics, and some additional nutrients and
soluble organics by coagulation or precipitation in the alum coagulation process.
Realizing the importance of the demonstration of this new technology to the textile
industry, BRW sought and obtained an Environmental Protection Agency demonstration
grant (EPA grant S801192). The grant provided sufficient funding so that the treatment
system could be evaluated in detail over a one-year period of plant operation in order to
fully define the system capability and to correlate production and wastewater data. The
specific objectives of the grant project were as follows:
— Characterization of the raw waste,
— Characterization   of the mill production in terms of fibers, chemicals, and
processes
— Determination of the operating characteristics of each unit treatment process,
— Establishment of the treatment capabilities of the total system under various raw
waste compositions,
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