The addition of anaerobic digester units at the East Alexandria Wastewater Treatment Plant, the Egyptian city’s largest wastewater treatment facility, is reducing the amount of sludge that needs to be trucked off site and using methane captured inside airtight digesters to help power the plant.

Prior to the addition of the new digesters and cogeneration unit, most of the sludge processed at the 176-million-gallon-per-day wastewater treatment facility was dewatered, but not treated. As a result, the sludge had to be trucked to landfills nearly 29 miles away. With the landfill reaching its saturation point, Egypt’s Construction Authority for Potable Water and Wastewater decided to add the capability to treat the sludge at the plant rather than truck it to a landfill even farther away.

The $115-million project added a 50,400-sq-m unit inside the existing plant that utilized a sludge-thickening reservoir, anaerobic digesters, gasometers and a cogeneration unit.

The project team, led by a consortium of Suez Group and the Arab Contractors, says the multiple nationalities of the team’s members allowed for the exchange of expertise and drove innovation, such as the first completely air-tight tanks of their kind to be built in Egypt. The completed project has reduced the quantity of sludge produced by 35% and has allowed the plant to achieve 60% to 70% self-sufficiency in energy generation.

Ahmed El-Adalany, a board of directors member for the Arab Contractors, says he hopes the project’s successful completion demonstrates the viability of resource recovery in Egypt and serves as “a catalyst for encouraging the Egyptian government to create similar units nationwide.”