Inorganic residual from kraft or soda pulping separated from green liquor in the chemical recovery cycle.

Endpoint summary

Additional information

Green liquor sludge is an inorganic UVCB substance and it is not biodegradable in a sense of microbiological utilization as a source of carbon and energy. In favorable environmental conditions, the constituents may still be subject to biologically mediated processes leading to biotransformations. Elemental carbon, carbonates and inorganic sulfur constituents take part in the natural biogeochemical cycles of carbon and sulfur. The sulfur cycle and carbon cycle are of major importance to aquatic and terrestrial life. These cycles consists of biological (and abiotic) processes that transforms the elements to meet the purpose and needs of the target organisms.

These cycles transfer, degrade and transform speciation of the inorganic constituents by characteristic way and depending on local environmental conditions. Anthropogenic emissions of GLS constituents in to the environment will be inevitable affected by these natural cycles. Green liquor sludge contains (heavy) metal constituent in trace amounts, which can be regarded nontransformable (persistent) in the environment.