​Plants for private or public sewage

These systems are designed and built when the load is at least 100 people.

The plants are usually composed of four stages:

FIRST STAGE: Pre-treatment

This phase may include:

• grilling
• lifting
• elimination of oils and sands (in case of  mixed sewage)
• homogenization
• primary sedimentation

STAGE II: Biological oxidation

• oxidation (usually using activated sludge)
• final sedimentation
• recirculation of activated sludge

This stage resolve some issues, such as:

• denitrification (biological denitrification)
• removal of phosphorus (dephosphatizing)
• final disinfection (chlorination, ultraviolet rays, etc ...)
• final filtration (sand filters and activated carbon filters)

STAGE IV: Sludge dewatering

This phase includes the following treatments:

• stabilization of the sludge
• conditioning and dewatering (centrifugal sludge thickeners,  belt-press filter, etc ... )