Determination of the total hardness in industrial cooling water using image identification

The determination of hardness in water is a useful parameter to control the quality of water for industrial and households´ uses. The present work proposes a digital image-based (DIB) titration as an alternative to the conventional EDTA titration. Experimental results obtained by this new methodology shows that the linear range of hardness detection ranks from 0 to 140 mmol/L. This method gave a reproducibility of 0.22% R.S.D and a recovery of 95.5%~102.5%. This new methodology has the advantage of being rapid, accurate and automatic determination.