Project Outline

Ahwaz city is divided into two eastern and western parts via Karoon River which is the only navigable river in Iran. The river not only supplies Ahwaz inhabitants with drinking water but also provides the water required for agriculture and industries in the area. Mãleh stream, 5 km from the city, is located in north – south direction and ultimately pours into shãdegãn lagoon after traversing some 80 kilometers. Human sewage which pours into this stream, got water and sewer authorities of Ahwaz city provide the requirements to stem the entrance of wastewater into the stream; they also planned to treat the wastewater and discharge it into the stream.

The plant’s daily treatment capacity is 112,000 cubic meters which serves a population of 522,000 inhibited in eastern part of Ahwaz city. The project applies the advanced technology of Sequencing Batch Reactor (SBR).

Treatment process

• Primary treatment unit: This unit is comprised of screening as well as girt & grease removal basin which separates coarse particles (e.g. sticks, plastic materials, stone, etc.) as well as fine components (grease, gravel and sand) to stem the processes that might damage treatment equipment. The maximum daily treatment capacity of the plant is 190,800 cubic meters.
• Biological treatment: This part of treatment is done in the SBR tank.
• Final treatment: This unit is design to disinfect the water before being emptied into the stream. The disinfection process is done by UV machine.
• Sludge unit: This section consists of sludge holding tank, floating pump station, sludge thickener unit, disinfection & filtering basin and sludge dewatering area. The processed sludge is used in agriculture and etc. This is the first time in the country that an urban wastewater treatment plant is built with such dimensions using SBR technology.

Key Statistics

• Earth work: 420,328 m³
• Total concrete: 40,000 m³
• Reinforcement: 3,000 t
• Formwork: 70,000 m²
• Metal work: 1,200 t