What are residuals?

Residuals refers to a broad collection of materials which are generated through municipal and industrial processes and systems.  Often these processes or systems generate multiple products.  For example water treatment results in the production of both drinking water and water treatment residuals; wastewater treatment results in the production of both effluent (treated wastewater) and biosolids.

Typical municipal and industrial residuals include:

  • biosolids – a product of wastewater treatment;
  • ash – products of combustion;
  • pulp and paper residuals – products of paper manufacture;
  • water treatment residuals – a product of municipal or industrial water treatment;
  • landfill leachate – a product of landfill operations;
  • waste lime or lime mud – products of pulp and paper processing, cement manufacture, and mining;
  • wood waste – products of forestry operations and wood processing; and
  • food processing residuals – products of meat processing, viticulture and greenhouse operations.

Historically, many residuals were considered waste products, and managed unsustainably. 

We believe that our sustainability is dependent on the innovative management of our waste.  We view residuals as resources to be managed beneficially as opposed to wastes to be disposed of.  We manage residuals by capitalizing on their inherent characteristics and value, for example as a source of nutrients or organic matter.

We encourage you to explore this section of our website to learn more about the residuals we manage and some our innovative projects that utilize residuals as resources.

For additional information about SYLVIS's work with residuals visit Our Work.