Industry Leadership
Humanity faces a global water supply crisis. Less than 1% of all fresh water is readily accessible for human use and more than 1.8 billion people lack adequate access to drinking water. As water extraction levels from rivers, lakes, and aquifers approach historically maximum levels, water scarcity remains a serious concern across the globe. Entire regions in North Africa, as well as Australia and the Indian subcontinent, are unable to meet the water demands of urban areas and local farmers. Dwindling water supply is also an issue here in the United States. This decline has tripled water rates and increased water rationing in San Diego and other municipalities along the California coastline.
To help mitigate this mounting scarcity, the process of converting seawater into freshwater emerged as a potential source of new and abundant supply. However, older methods of desalinating seawater consumed significant amounts of energy, and historically desalination has been an unaffordable, impractical solution for most regions.
Now, Energy Recovery, Inc. (ERI) has designed and developed an innovative technology that dramatically reduces the energy required for seawater desalination.
ERI’s Pressure Exchanger™ (PX™) device recycles much of the energy used in seawater desalination by continually reclaiming the otherwise lost pressure energy from the reject or brine water with to up to 98% efficiency. This improves the energy efficiency of seawater reverse osmosis (SWRO) by up to 60%, making desalination an affordable, sustainable option to address the world’s water crisis.
The ERI PX device design is simple yet elegant. It is a free-wheeling pump constructed from a unique ceramic material made from aluminum oxide, which is sintered at high temperatures. This results in a construction material that is three times tougher than steel and does not corrode in seawater. The sapphire-like material makes the PX device a very reliable, low-maintenance solution, which has captured 70% of global market share in newly constructed large desalination plants worldwide.
The revolutionary PX device controls and balances the core processing center of a modern desalination plant, serving as its hydraulic CPU. The PX device allows designers and operators to re-adjust operating conditions in desalination membranes as salinity and temperature conditions change with the seasons or as performance changes with normal wear. These PX operating adjustments assure that the high-pressure pumps are always running at their most efficient operating point.
This is significant because in a typical desalination plant the large electric motors driving these pumps consume dozens of megawatts of energy. Every percent of improvement in efficiency means millions of dollars in energy savings over the life of the plant; thus enabling large desalination plants—often called “water factories”—to affordably supply much of the demand for fresh-water to cities like Chennai (India), Perth (Australia), Algiers (North Africa) and Barcelona (Spain).
ERI’s PX devices currently save more than 900 megawatts of energy and are reducing CO2 emissions by more than 4.6 million tons per year. More than 7,000 PX devices are in the market, supporting the production of drinking water for an estimated 25 million people globally.