Sewage treatment plant wastewater Urban Group of Oran

Oran - Algeria


Direction de l’Hydraulique de la Wilaya d’Oran (DHWO)


Control plans and implementation studies - Technical verification and ongoing monitoring of engineering studies and construction works - Technical assistance during the commissioning tests - technical assistance for a period of two years of operation of the station


The project involves the construction of a new wastewater sewage treatment capacity of 270,000 / d. the Urban Group of Oran, with the city of Oran and the surrounding communities.

The initial operation of the sanitation system is based on the flow of wastewater through a pipe diameter of 1200, serving as a discharge pipe that flows into the next Sebkha of Oran, the latter being an area protected by the Convention Ramsar.

The main project objectives are to intercept and purify the water of domestic origin primarily to help clean water and that, in the spirit of resource conservation and recovery of waste. Biological treatment, activated sludge with primary sedimentation average charge was used. It is expected that the sludge will be stabilized anaerobically (digesters). A device for dewatering digested sludge will provide a solids content of at least 25% of the settlement area has retained an area of ​​21 ha.

The industry has adopted:

  • Pre-treatment (screening and grit removal / oiling)
  • Primary treatment (4 decanters dia ~ 50 m)
  • Biological Reactors (4 pools of 21 m * 84 m),
  • Clarifiers (8 decanters dia ~ 55 m),
  • Treatment of sludge thickening (4 books dia 26 m), anaerobic digestion (4 digesters diameter 29 m) and mechanical dewatering.


Effluent to be treated: 1,665,000 Eq. hab

  • AADT: 201,400 / d
  • Peak flow daily nominal 270,100 / d
  • BOD5 Pollution load: 92,000 kg / day
  • COD pollution load: 229,000 kg / day

Pollution load MES: 97,000 kg / d.

  • Quality of the effluent:
  • max BOD5 Concentration: 25 mg /,
  • Concentration max COD: 125 mg / l,
  • Concentration MY max: 35 mg / l.