University of Missouri Extension

WQ449, New April 1995

Biosolids Glossary of Terms

Randall Miles and J.R. Brown
School of Natural Resources
Ken Arnold
Chief of Land Application, Missouri Department of Natural Resources

Municipalities and privately owned wastewater treatment facilities process domestic wastewater into sludge and effluent. The sludge is then processed into a secondary resource, biosolids, which has value for land application as a supply of plant nutrients and organic matter.

This guide defines the common terms applied to the generation and land application of biosolids. Consistent use of the correct terminology leads to a clearer understanding. For example, the definition of sludge includes biosolids. However, all sludges are not biosolids. Some sludges are excluded from land application; whereas a sludge defined as biosolids may be land applied.


WQ449 Biosolids Glossary of Terms | University of Missouri Extension

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