In the art world, it is fostered by an incessant rain of numbers in the media whenever an art star comes to its attention. Graffiti Artists Turn on Banksy: The Rise of Art Hate Anthony Haden-Guest August 6, 2014
For the music genre, see Sludge metal. Sludge. Sludge is a semi-solid slurry and can be produced as sewage sludge from wastewater treatment processes or as a settled suspension obtained from conventional drinking water treatment and numerous other industrial processes.
The sludge volume index (SVI), introduced by Mohlman in 1934, has become the standard measure of the physical characteristics of activated sludge solids. It is defined as the volume in ml occupied by 1 g activated sludge after settling the aerated liquor for 30 min (Dick and Vesilind, 1969). Analytics.