Al-Aweer Sewage Treatment Plant (STP) Upgrade, Dubai, United Arab Emirates
The municipality of Dubai, UAE, announced plans to upgrade the Al-Aweer sewage treatment plant (STP), one of the two wastewater treatment plants serving the city, as part of its strategic plan 2015-2021.
Based on the approved drainage and irrigation master plan, the Dubai municipality undertook an extensive drive to upgrade the existing STPs and enhance the performance of the entire sewerage system in the city.
The Al-Aweer STP upgrade will make the city future-ready for the anticipated increase in sewage that would result from the rapidly increasing population.
Al Aweer STP extension details
The AED 144m ($39m) expansion will increase the plant's capacity by 65,000m³ a day. Veolia Water Solutions and Technologies, a subsidiary of Veolia, was selected as a distinguished supplier for the project in March 2015. Under the contract, the company provides engineering, procurement and construction services for the project.
Al-Aweer sewage treatment plant details
The Al-Aweer sewage treatment plant is located 25km away from the city centre and receives sewage from both domestic wastewater and septage. Optimal operation of the plant is essential for the city as it performs both tertiary wastewater treatment for irrigation reuse and sludge treatment for reuse as a soil fertiliser.
The plant was initially designed with a capacity of 130,000m³ a day, which was later upgraded to 260,000m³ a day.
Past expansion at Al-Aweer STP
The earlier expansion carried out by ACWA Services at the Al-Aweer STP included process additions, renovation to the existing facilities, facility modifications, testing, cleaning, calibration and maintenance.
In the preliminary treatment unit, minor modifications were made to the existing inlet chamber, yard piping modifications were made to bypass the existing inlet chamber, screening building was fitted with three travelling screens by replacing the existing ones, the existing aerate grit chambers were modified, and minor modifications were made to the pre-aeration tanks.
Phase II of the Ganga Action Plan Project primarily involves the construction of a new 140,000m³/d sewage treatment plant (STP).
Six new primary settling tanks similar to those of the existing ones and a new flow-splitting chamber to uniformly distribute flow to the new settling tanks were installed.
The secondary biological treatment facility was installed with two new flow splitting chambers and three aeration tanks. Additional anoxic treatment facilities were added to improve the sludge setting characteristics.
The tertiary biological treatment unit was installed with a flow-splitting chamber, a new big-filter recirculation pumping station and two new tertiary settling tanks. The upgrade also included modifications to yard piping and replacement of biological filters.
The existing pre-chlorinators and post-chlorinators were replaced with larger units, chlorine storage facilities were modified to provide a safer operation and a new chlorine scrubber was installed to neutralise leaks.
The sludge consolidation unit was installed with four new gravity sludge thickeners. The consolidation system was modified to provide additional digester feed and centrifuge feed pumping capacity, a new polymer make-up and feed system was added, and dedicated odour exhaust fans were installed for each consolidation and holding tank.
The existing dewatered sludge handling system was modified and a provision was created for additional high-solids centrifuges. A new air drying facility and sludge drying beds were also added to the sewage treatment plant.