TREATABILITY STUDIES AND DESIGN CONSIDERATIONS
FOR A TEXTILE MILL WASTEWATER
Mriganka M. Ghosh, Professor
Department of Civil Engineering
University of Missouri
Columbia, Missouri 65201
Franklin E. Woodard, Professor
Otis J. Sproul, Professor
Department of Civil Engineering
University of Maine
Orono, Maine 04473
INTRODUCTION
The Guilford Industries mill of Guilford, Maine is a textile processing mill.   Its operations consist of dyeing, carding, spinning, weaving, knitting and finishing of fabrics,    and
as such it can be classified as a complete mill producing material for the garment industry.
The mill is located on the Piscataquis River, into which its wastes are discharged.   The
production of the mill can vary widely from season to season and with changing business
demands, varying between stock and piece dyeing production.   During the preliminary
wastewater survey it was established that the maximum mill production consisted of
66,000 lb per week of material from the stock dyeing operation and 60,000 lb per week
from the piece dyeing operation.   The material processed included acrylic, polyester, nylon and wool.   Further, several in-plant changes resulted from the close coordination between the plant personnel and the engineers conducting the survey.   Installation of a new
washer system reduced washer wastewater flows from 100,000 gpd to 30,000 gpd.   Modification of the piece dyeing system reduced waste flows from this operation from 200,000
gpd to 78,000 gpd.   As a result of these and other minor in-plant changes, the average
daily flows projected for design were reduced from an average of 478,000 gpd to 250,000
gpd, a reduction of approximately 48%.   Recently, due to a change in market demands,
Guilford Industries had virtually ceased all piece dyeing operations and switched to stock
dyeing although the projected wastewater flows remained unchanged.   The pollutional
load had changed somewhat.
The common methods for the treatment of wastewater from textile mills involve color
removal and reduction of organic strength.   Generally, these goals can be achieved using
biological and physical-chemical treatment methods.   While biological treatment methods
are effective for the removal of organic material, they have largely proven ineffective in
the removal of color, primarily because of the nonbiodegradability of stable dyestuffs.
Carbon adsorption has been relatively successful in removing color from such wastes with
or without chemical coagulation.   A combination of biological-chemical adsorption treatment schemes have been successfully employed in the treatment of textile mill wastes [ 1 ].
The objective of the pilot study reported herein was two-fold:   (a) to evaluate the
treatability of mill wastewater alone (Alternative I) as opposed to tne treatability of the
combined mill wastewater jointly with the municipal wastewater from the Town of Guilford (Alternate II); and (b) to develop parameters for designing full-scale facilities and to
perform an economic evaluation of the two alternatives based on construction and operating costs.
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