Cases

Dubai municipality wastewater treatment plant

Client: Dubai municipality
Location: Jebel Ali, Dubai, United Arab Emirates
Period: 2016-2019

Project background

Dubai municipality needed to expand the sewage treatment of Dubai in order to be prepared for the visitors of the EXPO 2020 Dubai and the future population growth. Moreover, the expansion ensures that the sewage water is treated up to international standards. When the plant is finished, it will be the largest sewage treatment plant in the United Arab Emirates. The expanded sewage treatment plant treats almost 400,000 cubic meters of sewage water every day.

Sustainability challenge

Sustainability and recycling water is crucial for the United Arab Emirates since it is one of the top 10 most water-scarce countries in the world. The challenges of the United Arab Emirates are the scarcity of aquifers and the high cost of desalination of water.

Project partners and solutions

The main contractor of the expansion was a joint venture of Besix and L&T Construction, and they needed a trustworthy solution for removing sludge from primary settling. Thus, they turned to Econet Group and DEWA chain scraper systems.

Innovative solutions for wastewater treatment

In order to alleviate water scarcity and reach the wanted treatment results, 20 DEWA chain scraper systems, 20 DEWA scum removal pipes, and 120 DEWA overload weirs were delivered with installations to the primary clarification of the sewage treatment plant. In addition, in order to ensure working safety, training of the staff was included in the project.

The efficient primary clarification is important since it removes the finer solids out of wastewater, and it reduces the load in the following phases of sewage water treatment. The treated sewage water allows the city to cut back the use of expensive desalinated seawater, which is used for instance for irrigation, by 700 000 000 litres per day.

In the United Arab Emirates, the sewage is collected by vacuum trucks from septic tanks to the sewage treatment plant. However, while the sewage water is in the septic tank, hydrogen sulfide develops into the sludge. Hydrogen sulfide is a toxic and aggressive gas, and it can deteriorate materials and plastics. Thus, the material choices of the DEWA chain scraper systems were taken into account carefully, so that the systems would last for years. The chains of the DEWA chain scraper systems were produced from thermoplastic polyester resin, which can endure hydrogen sulfide.

Advantages of DEWA systems

DEWA chain scrapers are reliable and user-friendly solutions for rectangular settling basins. What is special about DEWA chain scrapers is that they can be built on top of each other in two to three layers.

DEWA chain scraper systems have a unique tensioning system that allows chain tensioning without draining the tank. DEWA chain resembles a bicycle chain and the system is tightened above water level with a simple screwing system. DEWA tensioning system prevents misalignment faults, which are caused if the chain gets loose. These features are very convenient when the sludge collector is totally under the water and is not visible to the operator. This saves time and resources and makes it the most operator-friendly solution.