Think of the last time you ran a settleability test at an activated sludge wastewater treatment plant. It was probably nothing to write home about.Sometimes you might wonder why you run the test so much. It never really changes, so why not just run it once a month instead of once a week? It seems every plant has its own standard operating procedure (SOP) for running the settleability test.As ordinary as this test may seem, it’s important to understand how it should be performed and the valuable data it provides. A case study will show how the test can prevent
