Filamentous bulking is a solid–liquid separation problem well known to activated-sludge plant operators. The use of curative additives is a rather delicate solution and the tools developed to anticipate it seem limited. To complement existing sludge sedimentation monitoring tools,
a new test to assess the propensity of activated sludge for filamentous bulking was developed. It consists of challenging the sludges by feeding them under conditions favoring filamentous bacteria for 24 hours. The effects of such an acute treatment on sludge settleability is subsequently
assessed through a simple sludge volume (SV30) measurement with reference to a control. The sludge can then be evaluated as prone to bulking (unstable sludge) or not (stable sludge). Such a test can be used to predict the occurrence of filamentous bulking in activated-sludge treatment
plants. This so-called acute bulking test requires simple equipment and can be done by any wastewater treatment plant operator.
Water Environment Research® (WER®) publishes peer-reviewed research papers, research notes, state-of-the-art and critical reviews on original, fundamental and applied research in all scientific and technical areas related to water quality, pollution control, and management. An annual Literature Review provides a review of published books and articles on water quality topics from the previous year. Published as: Sewage Works Journal, 1928 - 1949; Sewage and Industrial Wastes, 1950 - 1959; Journal Water Pollution Control Federation, 1959 - Oct 1989; Research Journal Water Pollution Control Federation, Nov 1989 - 1991; Water Environment Research, 1992 - present.