Anaerobic digestion of ice-cream wastewaters using the UASB process

A set of ten upflow sludge blanket digesters was examined as five pairs (one control and four test reactors) to assess the way in which controlled nutrient variations affected the performance of the reactors in treating a simulated ice-cream wastewater. An alternative carbon source was used and additional concentrations of calcium and cobalt were examined. The results show that the waste itself is capable of being treated by the UASB process, with granulation commencing after 60–70 days. However, of the supplements, only calcium had any significant effect.