Zoosloeal Viscous Bulking in a Pinus radiata TMP/ONP: OMG Recycled Fibre Newsprint Activated Sludge Plant

摘要

In this study, we showed that bulking of an activated sludge plant treating newsprint mill wastewater was due to Zoogloeal viscous bulking (or hydrous bulking); a condition that can occur when there are high concentrations of readily dcgradable organics (e.g. resin acids, fatty acids and soluble carbohydrates) and/or low macro-nutrients (N&P) and/or lengthy anoxic conditions preceding aeration. At Norske Skog's Albury Activated Sludge Plant (ASP) Zoogloeal viscous bulking appeared as microscopic amorphous clumps and formed a crust on wastewater during secondary clarification together with significant foaming in aeration tanks. Production of foaming polysaccharides/exopolymeric substance (EPS) was confirmed using Methylene Blue stain; dispersed and light blue floe characteristics were observed. This condition resulted in the production of white billowy foam, which adversely impacted on the settleability and dewaterability of ASP sludge.