Alcoa Commercializes ‘Engineered Wetlands’ Wastewater Treatment

Alcoa has entered into an agreement with German-based engineering and construction company, Bauer Resources, to commercialize Alcoa’s Natural Engineered Wastewater Treatment technology that mimics natural wetlands to sustainably treat wastewater.

Under the agreement, Bauer will use Alcoa’s engineered wetlands technology to deploy wastewater treatment systems globally.

The system imitates the natural process of wetlands to clean and disinfect process water. Alcoa says it uses 40 percent less energy and has 60 percent lower operating costs than traditional systems, functions without the use of chemicals, and does not emit odors associated with conventional tank systems. Treated water can be reused in manufacturing processes or for irrigation.

The system involves three steps (pictured):

1. An anaerobic treatment tank that removes metals and breaks down and separates organic material in the water;
2. A passive engineered wetland that utilizes vegetation for further treatment of organics and removal of nitrogen; and
3. A cell housing bauxite-based technology that disinfects and polishes the water. The result is water treated to the same or better quality as that of a conventional system.

Alcoa has been engaged in engineered wetlands technology development and deployment at various Alcoa locations for the last 10 years, with the most recent and largest being a system implemented in the Kingdom of Saudi Arabia at the Ma’aden-Alcoa joint venture project site. There, the technology will reduce the facility’s water demand by 2 million gallons a day, saving $7 million a year in water purchase costs for the integrated aluminum complex, the company says.