Mostaganem-Arzew-Oran drinking water production plant (Algeria)

In the early 2000’s, in order to cope with global environment challenges of water management in a context of hydric stress, the Algerian authorities initiated a series of major water infrastructure construction projects.

On April 24th 2006, the Agence Nationale des Barrages et Transferts contracted with the consortium SUEZ / MAPA for the design, build and operation & maintenance of the drinking water treatment plant of Sidi Lahdjel.

With a capacity of 561,600 m³/day, the plant of Sidi Lahdjel, the second largest plant in Algeria, is part of a large project of water transfer system which provides today the neighbouring cities of Mostaganem-Arsem-Oran (MAO).

water treatment

The raw water, coming from Chéliff dam, is first pretreated in a pre sedimentation plant (820,800 m³/d) and then conveyed to Sidi Lahdjel drinking water treatment plant (Mostaganem-Arsem-Oran).

aeration:

The aeration is the first stage of the drinking water treatment. Sidi Lahdjel is equipped with a cascade aeration.

clarification:

The water is then clarified 6 Densadeg® 2D, an efficient separation process, allowing to obtain :

• A speed lamellar settling,
• Efficient sludge thickening
• High quality settled water
• Low sensitivity to the load and flow variations
• Net settling surface of 169 m² with fast mixers
• Speed lamellar settling with 6 settlings in operation: 23 m³/m²/h
• Speed settling: 13,5 m/h

filtration:

The clarified water is filtrated on 18 Aquazur® V sand filters (unit flow: 1,300 m³/h)

• Surface of each filter: 151.4 m²
• Standard speed filtration : 8.58 m³/m²/h

physico-chemical disinfection :

The filtered water receives a final disinfection treatment with injection of chlorine gas.

The water is then stored in 2 tanks (unit capacity: 55,000 m³), allowing to maintain a production reserve of more than 4 hours with a flow at 561,600 m³/h.