ALGERIA: Energy Recovery’s PXs to reduce the energy cost of desalination

While Algeria wants to increase the proportion of its drinking water supplied by desalination to 50% by 2030, it also wants to reduce the environmental impact of this practice, which is reputed to be extremely energy-intensive. This is why Energy Recovery recently placed an order for PX® pressure exchangers. The energy efficiency technology supplier, based in California in the United States of America, has won a contract worth 28 million dollars.

Under the contract signed with the Algerian government, the PX® pressure exchangers are to be delivered by the end of 2023. The equipment will be installed in all the North African country’s seawater desalination plants, which are expected to have a capacity of 3.6 million m3 per day, for 19 installations by 2024.

PX® technology will “reduce energy consumption in desalination by up to 60% and offer the lowest life cycle cost of any energy recovery device on the market”, says Energy Recovery. This will enable Algeria to move towards less energy-intensive and more sustainable desalination.

Energy Recovery’s PX® pressure exchangers installed in a wastewater treatment plant©Energy Recovery

Theoretically, the energy bill for desalination depends on the process used. Distillation is a thermal process in which salt water is heated in a boiler to recover fresh water. This technique requires up to 15 kWh per m³. The reverse osmosis process, on the other hand, requires between 2.5 and 3 kWh per m³. This other method involves applying pressure to a volume of salt water through a semi-permeable membrane that retains the salt and other impurities.

Also Read – ALGERIA: A new agency will support the national desalination policy

Energy Recovery estimates that these PX units will also prevent more than 560,000 tonnes of carbon dioxide equivalent (CO₂) from entering the atmosphere each year, the equivalent of taking around 120,000 passenger cars off the road.

Inès Magoum