It was found that at 0.6 and 1% vol, of molasses, the reduction of sulphates occurred at the level of 0.7 g [S-SO42-], while at its concentration 2 and 5% vol., the maximum amount of the reduced sulphates increased to 0.826 and 1.256 g [S-SO42-], respectively, which corresponds to 60 and 92% of sulphate conversion. A decrease in COD varied from 32 to 40%, and was the greatest for the medium with 5% vol. of molasses.
The results indicate that molasses, likewise some municipal waste, can be used as an alternative source of carbon acting as electron donor in reduction of sulphates to sulphides.