White Paper

Highly efficient energy recovery devices

Energy Recovery Devices (ERDs) are at the core of saving energy in the operation of any seawater reverse osmosis (SWRO) desalination facility. Isobaric or “positive displacement” devices such as the PX Pressure Exchanger devices are the most efficient solution available today and can reduce the energy consumption of seawater reverse osmosis (SWRO) systems by up to 60 percent.

Energy Recovery has the largest installed base of ERDs in the industry. Considering only large desalination plants, the Company has a global installed base of over 15,000 individual PX devices in more than 500 desalination plants. Factory acceptance testing is done on 100% of the PX devices.

This paper will examine and quantify the efficiency of PX devices based on an extensive database of actual test results. Significant historical performance data was evaluated and analysed to validate efficiency figures and guarantee increased efficiencies for several PX device models, including the PX Pressure Exchanger models PX-220, PX-260 and PX-300 units, The existing models offer 96.8% efficiency guarantees, which in turn offers significant energy savings for plant owners and operators. Test data will also quantify the efficiency gains provided by Energy Recovery’s Quadribaric technology.

The Company’s newest device, the PX-Q300 incorporates the innovative Quadribaric technology doubling the number of pressure exchanges per revolution. This new PX-Q300 improves efficiency – with a warranted minimum efficiency of 97.2%.

Many of the globally installed units have been in operation for as long as 12 years. With zero failure as a result of PX technology designed ceramics, research indicates that PX devices will continue operating well into the future.