Water in the desert: ACCIONA in Chile

ACCIONA will use desalination technology to supply water for the mining industry and local residents in one of the most arid regions in Chile.

The Atacama Desert in Chile is one of the driest on the planet. ACCIONA will bring water to the area with a desalination plant near Copiapó. This plant will ensure the water supply for the mining industry, which generates nearly 50% of the area's wealth.

Copiapó, one of the largest cities in the Atacama Desert, has historically been a mining and agriculture region. These activities increased progressively to the point where the Copiapó Valley was literally drying up due to the fact that water needs were exceeding the natural replenishment capacity of the aquifers.

After years of considering various options, the CAP company of Chile, the country's steel and mining sector leader, chose desalination as the safest and most sustainable for the long term. ACCIONA Agua was selected for the design, construction, start up and 20-year operation of a seawater desalination plant with a 63.5 million dollar investment (about 45 million euros).

Respectful of the environment, the plant will begin operations in 2013

The desalination plant will supply water needed for iron mining exploitation at Cerro Negro Norte to ensure continued industrial development in the area. Excess water will be used to satisfy other industrial and consumer needs, including human consumption. In total, water production from the plant will reach 54,000 m3 per day, of which 17,000 will be used by the mine and the remaining 34,000 will be divided among other mining, agriculture and livestock activities in the area.

Understanding Process

The water will be collected from the Pacific Ocean at a depth of 17 m. From there, it is sent to a pumping well and then to the desalination plant located 1,300 m from the shore. Once there, the water will be subjected to desalination and potabilization processes and the brine will be returned to the ocean through a system of diffusers that prevent salt concentrations that would otherwise be toxic for marine life. The plant will use reverse osmosis for desalination with an innovative pretreatment process. This technique is especially interesting due to its flexibility, as it enables the treatment of various types of raw water while being economically competitive and respectful of the environment.

The pretreatment process incorporates technology developed by ACCIONA Agua to protect the membranes against phenomena such as red tides and jellyfish, which are common in this area of the Pacific Ocean.

Respectful of the environment, the plant will begin operations in 2013

At the start of operations planned for the first half of 2013, the plant will process 200 liters per second but will later be able to produce 600 liters per second (or 54,000 m3 per day approximately).

The plant will be located near the Punta Totoralillo Port in northern Chile (south of Peru, between the Loa and Copiapó rivers that run through the Antofagasta region and the northern Atacama region).

In figures

• 63.5 million dollar investment.
• 17 million liters of initial daily capacit.
• possible increase to 52 million liters daily.
• 4,000 state-of-the-art reverse osmosis membranes.

Julio Zorrilla

ACCIONA Agua International Construction Director and Copiapó Desalination Plant Construction Director

This project has the twofold challenge in processes and engineering. The occasional appearance of algae in the area led us to develop a proprietary process to treat the water following development and testing in Spain. It will be used for the first time in the Pacific Ocean. Likewise, the application of mining industry methods and criteria positions us at
the top of a growing market in countries considered to be preferential by ACCIONA.

José González M.

Sustainable measures