This document provides information on the processes and technologies for inorganic substance and nutrient recovery from sludge.

This document is applicable to sludge and products from urban wastewater collection systems, night soil, wastewater treatment plants for urban and similar industrial waters. It includes all sludge that can have either similar environmental or health impacts, or both.

Hazardous sludge from industry and dredged sludge are excluded from this document.