Industrial Waste-water Characterisation and Image-Based Assessment of its Color Load

Abstract

The characteristics of waste-water discharged from a reactive dyeing machine are examined and a simple method of quantifying its color load proposed. The discharged waste-water is typified by a pH value of 10.2, a turbidity value of 230 NTU, a color load of 290 mg/L and total suspended solids of about 970 mg/L. Application of digital image correlation to assess the color load in waste-water is explored through the use of Image Correlator plugin installed in the ImageJ software. The pixel scatter plot from the image correlation exhibit a characteristic spread with increasing concentration of dye solution thus demonstrating its applicability for waste-water color load assessment. The correlation coefficient derived from the image measurement, correlates almost linearly with the dye concentration in water and can thus be used for assessing the efficacy of color removal from the waste-water. With proper calibration, the resultant correlation curve can be applied in the quantification of the colour load in waste-water.

Keywords: Digital Image Correlation, Waste-water, ImageJ, Color Load, Image Correlator, pixel scatter plot