Investigators: Ashok Kumar and Dr.M.K.Ghose(1991)

Title	Objective(s)	Methodology	Conclusion/ Contribution made	Benefits
Impact of coal washery effluent on surface water and its abatement measures	1.To characterise the coal washery effluent 2.To estimate the quantity of coal fines lost into a river system 3.To study the settling characteristics of the suspended solids.	1. Sudamdih coal washery of BCCL and the river stretch near the washery were chosen for the study. 2. Different conventional and synthetic flocculants were used and the settling behaviour of the suspended solids was studied. 3. A series of tests were conducted with the addition of varying dosages of different coagulants and percentage removal of suspended solids and the quality of the supernatant were tested. 4. The dispersion profiles of the pollutants in the rivers have been represented by equations of the SS and COD at different down stream stretch of the river have been evaluated mathematically.	1. Apart from SS, COD values also were found to be abnormally high. These are of great danger to aquatic life and creating acute problems to the down stream water works. 2. Recovery of coal fines with the aid of suitable reagents can be recycled or safely discharged to the surface water	1. In addition to the removal of pollution and siltation problem on the river bed a large quantity of very good quality coking coal can be recovered. This will be of great benefit to Indian economy. 2. The mathematical models deeloped can be utilised for the evaluation of pollutants at the down stream locations of the washery. 3. The study will be useful in designing cost affective effluent treatment plant and the process will work on an industrial scale at various sites.