The report gives results of an investigation of the use of adsorption resins to remove colored dyes from textile dyeing wastewaters, using an automated benchscale pilot unit. This could make possible the reuse of the treated wastewaters in subsequent dyeing operations. The scale of operation facilitated accumulation of reliable data on which to base cost estimates for commercial operation. At a wastewater treatment rate of 20,000 gpd by resin adsorption, the amortized operating cost is estimated to be $3.47/1000 gal. An estimated capital investment of $86,000 will be required. These costs are believed competitive to other possible dye waste treatment processes. Use of properly selected adsorption resins was found to be effective for removing dyes from textile wastewaters. The finding is particularly important to the use of dispersed type dyes, which are largely inert to biological waste treatment processes, passing through such treatment relatively unchanged. In addition to the possible reuse of treated wastewater and elimination of possible damage to natural aesthetics, the removal of color substances reduces the tendency toward several other ecological problems in effluent receiving waters. Color substances tend to reduce light penetration and subsequent production of oxygen by photosynthesis, damaging marine life and algae growth. They also chelate metal ions, and some are toxic and suspect carcinogens. (Color illustrations reproduced in black and white)

Prepared under Grant no. R803455-01, program element no. 1BB610. Issued July 1977. Includes bibliographical references.