Maximizing Energy Savings for Water Reuse

As water scarcity becomes a pressing issue in many regions around the world, there is a growing recognition that we need to make the most of available water resources. Water reuse helps to alleviate the strain on freshwater sources and reduces our reliance on sources such as groundwater and storm capture, which are impacted by climate change and drought.

Currently less than 10% of wastewater is reused globally¹, but governments around the world are starting to implement policies to increase its adoption such as setting water reuse targets, providing incentives for water reuse projects, and developing standards for treatment and reuse.

Advances in water treatment technologies such as advanced filtration, membrane technologies, and disinfection methods have improved the quality of treated wastewater. Triple barrier methods are even able to remove dissolved salts and so-called “forever chemicals,” or per- and polyfluoroalkyl substances (PFAS), from wastewater, making it suitable for drinking and irrigation. However, triple barrier technologies can also be energy intensive.

Sustainability Meets Cost Savings

Energy Recovery’s line of energy recovery devices (ERDs) can deliver significant savings for membrane-based water treatment systems. Our core PX^® Pressure Exchanger^®, low-pressure PX (LPPX), and ultra-high pressure U Series work by harnessing pressure within a reverse osmosis (RO) system as the brine exits and recycling the pressure energy, maximizing system efficiency and reducing operating expenses.

Our low-pressure PX can deliver up to 30% energy savings for low-pressure RO systems used in water reuse applications². Consuming no electrical power and engineered with only one moving part made of highly durable and corrosion-resistant ceramic, the PX offers substantial energy savings and ease of integration resulting in reduced operational expenditures. Existing systems can often be retrofitted with PXs using existing equipment without impacting flexibility or reliability, with the added bonus of potentially increasing system capacity. 

Energy Recovery has spent 30 years perfecting the reliable, field-proven, and trusted PX Pressure Exchanger technology, which requires no scheduled maintenance.

Low Pressure PX Technology Features:

• Operates at low pressures 5.5-27.6 bar (80-400 psi)
• Models ranging from 7-59 m³/h (30 to 260 gpm) per unit
• Ideal for potable, non-potable, agricultural, and industrial water reuse

¹ Source: https://inweh.unu.edu/half-of-global-wastewater-treated-rates-in-developing-countries-still-lagging

² The PX consistently recovers 95% of the available energy otherwise wasted in RO systems, representing up to 30% energy savings in a typical LPRO system with a minimum recovery of 75%.

³ Based on performance data of the PX® Pressure Exchanger® technology in Seawater Reverse Osmosis (SWRO) applications