A new treatment process has been developed for simultaneous removal of colors and heavy-metal pollutants. For all the cases studied, the untreated effluent had a color content of l200-8000 c.u. Using this new treatment process, the color content was effectively reduced to below 100 c.u. This corresponds to above 90 percent color reduction. Interestingly, the results show that there is a linear relationship between the reduction of color content and the removal of toxic metals.
Treated effluents having a low color content also have a low copper concentration.
The operating costs of the new process will be much lower than the chlorination method which is the cheapest among the existing processes. For example, a number of companies currently use the biological and chlorination methods to achieve color reduction. The operating costs for chlorination alone are reported at about 40-90 cents per 1000 gallons to reduce the color concentration from around 1200 c.u. to 300 c.u. Using the novel process, this color reduction can be easily achieved at bout 50 cents per 1000 gallons. B. Much Shorter Retention Time.