Sewage sludges from treatment plants are several types according to their characteristics: such as treatment sludge, raw sludge (fresh sludge), decayed sludge, or sludge from phosphate precipitation unit. However, the sludge, regardless of its shape, must be technically controlled and disposed of in a way that does not harm the ecosystem.

Within the scope of these studies, eluate preparation techniques and extraction of solid wastes and sludges are used by accredited laboratories. The laboratories are based on the following standards issued by the Turkish Standards Institute:

• TS EN 16192 Classification of wastes - Analysis of eluates

• TS EN 12457 Characterization of wastes - Solid extraction analysis - Conformity test for solid extraction of granular solid wastes and sludges
• Part 1: Single-stage batch test for high solids materials with a liquid solids ratio of 2 l / kg and particle size less than 4 mm
• Part 2: Single-stage batch test for materials with a liquid solids ratio of 10 l / kg and particle size less than 4 mm
• Part 3: Single-stage batch test for high solids materials with a liquid solids ratio of 10 l / kg and particle size less than 4 mm
• Part 4: For materials with a liquid solids content of 10 l / kg and particle size less than 10 mm (diminished or not diminished)

The eluate preparation activities carried out within the framework of hazardous waste, solid waste and treatment sludge analyzes are carried out in order to store the treatment sludge or domestic wastes from the processors in regular storage facilities. These studies are carried out in accordance with the Regulation on Control of Hazardous Wastes issued in 2005.

Authorized laboratories operate in compliance with the TS EN ISO / IEC 17025 standard.