Sludge

For the music genre, see Sludge metal. For other uses, see Sludge (disambiguation).
Fecal sludge collected from pit latrines near Durban, South Africa, awaiting further treatment by drying

Sludge is a semi-solid slurry that can be produced from a range of industrial processes, from water treatment, wastewater treatment or on-site sanitation systems. It can be produced as a settled suspension obtained from conventional drinking water treatment,[1] as sewage sludge from wastewater treatment processes[2]: 23–25  or as fecal sludge from pit latrines and septic tanks. The term is also sometimes used as a generic term for solids separated from suspension in a liquid; this soupy material usually contains significant quantities of interstitial water (between the solid particles). Sludge can consist of a variety of particles, such as animal manure.[3][not specific enough to verify]

Industrial wastewater treatment plants produce solids that are also referred to as sludge. This can be generated from biological or physical-chemical processes.

In the activated sludge process for wastewater treatment, the terms "waste activated sludge" and "return activated sludge" are used.

Sludge from the food-processing and beverage-making industries can have a high content of protein and other nutrients. Thus, it can be processed for beneficial uses such as animal feed, rather than being landfilled.

  1. ^ Edzwald, James K., ed. (2011). Water Quality and Treatment (6th ed.). McGraw-Hill. ISBN 978-0-07-163011-5.
  2. ^ Bustillo-Lecompte, Ciro; Mehrvar, Mehrab (2017-05-03), "Slaughterhouse Wastewater: Treatment, Management and Resource Recovery", Physico-Chemical Wastewater Treatment and Resource Recovery, InTech, doi:10.5772/65499, ISBN 978-953-51-3129-8, retrieved 2024-11-06
  3. ^ Byfield, Mike (July 7, 1997). "Farmers line up for their slug of pulp sludge". Alberta Newsprint Co.