Sludge 12 : Heavy, slimy residue remaining from the treatment of municipal and industrial water and wastewater. Digested sewage sludge remains after decomposition under controlled temperature, pH, and mixing in a digester tank
EESiFlo North America, Terminology and Glossary: Water and Wastewater Terms, Pennsylvania, USA 2002. flowmeterdirectory.com/flowmeter_terminology, (Wtr and Wastewater - Amer) {559}