Case Study

PX Pressure Exchanger Reduces Barriers to Achieving ZLD in CTX Wastewater Treatment

Beijing BeiJieTe used a combination of internal recirculation high-pressure reverse osmosis (HPRO), nanofiltration, and their own industry-leading salt separation technology to treat wastewater. The combination of these three processes resulted in true ZLD, where there is no wastewater remaining at the end of the treatment process, and effectively separated and purified the salt present in the water.

The HPRO stages incorporated Energy Recovery’s PX Q300 pressure exchanger technology, which is able to capture pressure energy as wastewater moves through the HPRO process and recycle it back into the system, significantly reducing the amount of energy needed to pressurize the wastewater feed stream.

A Streamlined Process: Full-Service Energy Recovery and Pumping Solutions at an Advanced Textile Common Effluent Treatment Plant

Case Study around Energy Recovery Devices in Wastewater Treatment

The Pali Common Effluent Treatment Plant in Pali, Rajasthan, India supports 215 factories located in the surrounding Punayata Industrial Area. All the equipment in the plant is supplied by Aldee Water Pvt. Ltd. Advanced reverse osmosis water treatment was adopted to significantly reduce the stream volume being sent to the thermal system, reducing both CAPEX and OPEX of the thermal system. With added nanofiltration processes in place to separate salt, the high purity salt could then be recycled and sold.

To achieve more efficiency and cost savings, Detox Group and Pali CETP partnered with Energy Recovery, Inc. to install a suite of energy recovery devices, including both turbochargers and pressure exchangers, bringing higher uptime and availability to the whole system.

PX G1300 Reduces Peak Power Consumption 30% Over Adiabatic Cooler

CO2 refrigeration energy recovery case study

Energy Recovery’s PX G1300® pressure exchanger was installed at a Vallarta Supermarkets location in November 2022 to recover and recycle high-pressure energy within an existing CO2 system.

• Reduced peak power consumption approximately 30%*
• Cut average energy consumption approximately 14%*
• Installed and commissioned with no impact on regular store operations
• Second PX G1300 installation with Vallarta announced August 2023

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*Based on actual results collected between July 12-22, 2023. 30% reduction driven by eliminating intermittent onset of third compressor

First PX U40 for Wastewater Treatment Yields Savings with High Performance

Lithium wastewater treament sinochem china

This recent case study, which focuses on the first site to commission a PX U40 in early 2022—a lithium iron phosphate (LFP) plant in China—shows a significant reduction in both energy consumption and costs using the PX Pressure Exchanger for the second reverse osmosis stage and the PX U40 for the ultra high-pressure reverse osmosis stage to capture energy otherwise wasted in the wastewater treatment process.

European Supermarket Future-Proofs Refrigeration System, Reduces Costs Using PX G1300 Energy Recovery Device

Epta PX G1300 Refrigeration Case Study

In collaboration with Epta, a refrigeration rack manufacturer in Europe, the supermarket chain became the first in Europe to incorporate a PX G1300 energy recovery device into its CO2 refrigeration system.

With a simple design that needs virtually no maintenance, the PX G1300 lowers the energy use of a CO2 system by recycling pressure energy, allowing the system to run more efficiently. Choosing a PX G1300-enabled CO2 system comes at no additional cost to a supermarket, as it offsets the need for other components.

Once the PX G1300 was installed, the supermarket saw efficiency improvements over 30% at temperatures above 40°C (104°F), compared to a standard CO2 booster system.

ACWA Power Rabigh 3 IWP: A Large-Scale Plant Aimed at Energy Efficiency

Approximately 60% of the Kingdom of Saudi Arabia’s water comes from desalination currently – which consumes roughly 20% of the country’s energy usage – and demand is continuously rising. With the decoupling of power and desalination plants, it is now more necessary than ever to make desalination facilities energy efficient, and the government has directed water producers to decrease energy consumption as much as possible.

As one of the biggest seawater reverse osmosis (SWRO) desalination facilities in the world, ACWA Power Rabigh 3 IWP was designed to address the growing demand for water while also keeping energy consumption low.

By utilizing efficient solutions throughout the facility, the designers and engineers were able to reach their goal of reducing power consumption to under 3.2 kWh/m3. Energy Recovery’s PX devices were a key component in achieving the stated goal and, on an annual basis, will save ACWA Power Rabigh 3 IWP approximately 500 GWh each year.

The US’ First Municipal Installation of a BWRO Pressure Exchanger®

The Challenge
Planned Brackish Water Reverse Osmosis (BWRO) facility facing significant drop-off in water quality.

The City of North Point, Florida built a new brackish water reverse osmosis (BWRO) facility capable of producing 2.0 MGD of potable water by treating raw water from local wells with a Total Dissolved Solids (TDS) level of about 3,500 mg/L. However, the facility needed a flexible design because the conditions are expected to change over time. Nearby wells are degrading and the City anticipates that the raw water quality will degrade over time; historical data predicts salinity could increase by as much as 370% in the first 10 years of operations. The facility has two reverse osmosis (RO) skids, each capable of producing 1.0 MGD, which are designed to expand to produce 2.5 MGD each as demand for water rises. This wide range of operating conditions presented a significant design challenge.

The Innovation Solution
The US’ First Installation of a BWRO PX® Pressure Exchanger®

YuHuan, China powering up for 2008 Olympics

The Industry Standard Solution

The efficiency and life cycle costs of a plant’s energy recovery technology is critical to both securing SWRO projects and achieving maximum plant profitably through the lowest operating costs. Leading international OEM’s such as Acciona Agua, GE Water Process and Technologies, Siemens and Suez Degrémont have selected the PX modular technology for their SWRO projects because it consistently achieves real energy transfer efficiencies— up to 98%, making it the most efficient energy recovery device available today. At the core of the PX device is a single moving rotor made of tough engineered ceramic that is unaffected by chemicals, will not corrode, and requires no periodic maintenance. Over 80 OEMs are standardizing on PX technology with installations around the world, including plants such as Al Shuaibah III, Barcelona, Chennai, Hamma, Perth, Skikda, Torrevieja and Yuhuan.

YuHuan Project Facts

  • Capacity: 36,000 m3/day
  • 6 trains – 6,000 m3/day
  • 6 PX-220 Pressure Exchangers per SWRO train
  • 97.2% efficiency guaranteed
  • Plant went online in 2006

YuHuan, China Power Station

The desalination facility in China’s Zheijang Province is the largest desalination project in Mainland Asia. The plant, built by Beijing CNC Technology, Inc. supplies process water to new electrical power stations. The OEM’s decision to use Energy Recovery’s PX Pressure Exchanger® technology for the YuHuan desalination plant helped prepare the country for its 2008 Olympics. The 1,800 MW power stations expanded China’s electrical grid capacity in preparation for the 2008 Olympics. Rapid growth of the economy in China has stretched availability of electric power. Desalinating seawater by conventional “waste heat” recovery methods consumes a significant portion of a power plant’s energy input. Compared to conventional technology, the PX device cuts the amount of energy required to desalinate seawater for power plants by up to 68%. The use of PX technology at the YuHuan desalination plant enables the reduction in desalination plant power demand of over 4.4 MW- saving over $2.0 million per year. Other desalination plants, such as Beijing’s CNC 5,000 m3/day SWRO plant at China Petrochemicals Dalian built in 2003 also uses the PX device. The East China Electric Power Design Institute Ministry (ECEPDI) and Beijing CNC specified Energy Recovery’s PX-220s for YuHuan based on the proven high efficiency and two-year trouble-free track record of the PX-220 installation at Dalian China Petrochemical. Because of its 98% energy efficiency solution, China now leads the world in the adoption of efficient PX technology with close to 100% market share.

Hear about our work from Chinese water authorities in this video.

YuHuan Power Station SWRO Desalination Project

Energy Recovery (NASDAQ: ERII) develops award-winning solutions to improve productivity, profitability, and energy efficiency within the oil & gas, chemical, and water industries. Our products simplify complex systems and protect vulnerable equipment. By recycling fluid pressure that would otherwise be lost in critical processes, we save clients more than $1.4 billion (USD) annually. The PX Pressure Exchanger is a rotary positive displacement pump that recovers energy from the high-pressure waste stream of sea water reverse osmosis (SWRO) systems at up to 98% efficiency with no downtime or scheduled maintenance. Headquartered in the Bay Area, Energy Recovery has offices in Barcelona, Shanghai, and Dubai.

The world’s largest energy recovery device manufacturer delivers:

  • Proven SWRO Power Consumption as Low as 1.7 kWh/m†
  • No Scheduled Maintenance Shutdown
  • No Pulsations, or Complicated Controls
  • The Simplest Solution to Lowest Lifecycle Costs
  • Flexibility, Proven Reliability and Real Savings


Turkey’s industrial water needs restrained by expensive power

Location: Istanbul, Turkey
Project: Colakoglu Metalurji A.S.
Capacity: 9,600 m³/ day
Energy Savings: $USD 800,000 or 6.2 million kWh/year* CO2 savings: 3,627 tons/ year**
* energy savings estimates based on Turkey’s power cost of $0.13/kWh
** based on Energy Recovery’s proprietary Power Model analysis

The Challenge: 
Industrial Water Needs Restrained by Expensive Power

The quality and availability of freshwater supplies in Turkey are unpredictable.  This is because rainfall variations, geographical irregularities, urbanization, industrialization, and agricultural modernization all complicate water use for human, industrial, and agricultural purposes. Turkey has no natural oil or gas resources and must make deliberate and thoughtful decisions about its energy acquisition and use. In designing Turkey’s largest desalination plant for Çolakoglu Metalurgi Company in Istanbul, Aquamatch considered many energy-saving options including DWEER and selected Energy Recovery’s technology over the competition because it saves the most energy, has the highest efficiency, and requires little to no maintenance.

The Innovation Solution
: Energy Recovery PX Pressure Exchanger

The isobaric energy-recovering PX technology captures and recycles energy.  This innovation reduces the energy required for desalination, lowers capital costs by complementing a smaller pump, decreases the carbon footprint of desalination processing, and offers maintenance-free operation for the life of the plant. The PX device made the most financial and environmental sense for the plant since it offered Aquamatch the highest return on investment for the life of the plant.

The Result
: Energy Savings Mean Viable Independent Water Source

The considerable energy saved using PX technology means Aquamatch is able to supply the Çolakoglu Metalurgi Company with more affordable process water, leaving freshwater resources available to residents. Increasingly, industrial customers seek out Energy Recovery for these benefits: companies require an independent water source that does not disrupt municipal supplies and that minimizes cost and energy use. In the case of Istanbul’s SWRO plant, Aquamatch is making economic growth possible by reducing the plant’s energy needs by more than 6 million kWh of energy per year. This has lowered the annual cost by nearly $800,000 each year for the seven years the PX solution has been operating in Turkey.
EPC contractors all gave the same answer when Aquamatch and Colakoglu Metallurgy asked for information on building an environmentally friendly and efficient desalination plant: Energy Recovery.

Tianjin’s progress stalled without water

Location: Tianjin, China
Project: Tianjin Dagang Seawater Desal Plant
Capacity: Capacity: 100,000 m³/ day scaling to 150,000 m³/d
Energy Savings: US$7.45 million or 74.5 million kWh/year*
CO2 savings: 44,000 metric tons/year**
* energy savings estimates based on China’s power cost of $0.10/kWh
**based on Energy Recovery’s proprietary Power Model analysis

The Challenge: 
City’s Industrial Progress Stalled without Water

Limited water resources were holding back social and economic development in Tianjin Dagang, the largest industrial city in Northern China. An early adopter of desalination to meet municipal and industrial water needs, Tianjin sought to develop a massive desalination plant to enable a large, new industrial development. Building a water processing plant with an initial output of 100,000 m3/day and a future goal of expanding to 150,000 m3/day demanded seawater reverse osmosis (SWRO) technology that could efficiently desalinate and purify water.

The Innovation Solution
: PX Pressure Exchanger 220

In collaboration with Hyflux Pte Ltd., Energy Recovery created a cost-effective solution that allows the new Tianjin Dagang SWRO plant to generate huge quantities of water for its industrial customers. Though they had used competitors’ isobaric energy recovery devices in smaller installations, Hyflux built and commissioned the Tianjin plant to include the PX Pressure Exchanger® because the life cycle advantage to the PX technology includes efficiency, durability, and a track record of being maintenance free. The installed PX solutions reduce the required pump output by 55%, recycling massive amounts of fluid and pressure flows into energy and cost savings for China’s largest SWRO processing installation.

The Result
: Industrial Success and Local Jobs from Efficient Water Desalination

From the beginning of operation, Tianjin Dagang’s SWRO plant has achieved high efficiency and significant energy savings in excess of 74 million kWh each year. The PX trains are also reducing Tianjin SWRO’s CO2 emissions by approximately 44,000 metric tons each year – an equivalent of taking nine cars off the road in the US for one year. An Energy Recovery team that completed a one-year check on the installed PX trains found no measurable change in performance after a year of full capacity water production. Recycling energy from fluid flows to offer Tianjin a source of clean, reliable, affordable water has meant industrial development and the resulting economic benefits to the area are now more than possible—they are reality.

Parched on the Red Sea

Location: Sharm El-Sheikh, Egypt
Project: Marriot Sharm El-Sheikh Hotel
Product Configuration: AquaBold High Pressure Pump & Advanced TurboCharger
Capacity: 500 m3/day

The Challenge: Parched on the Red Sea

Miles and miles of gorgeous Red Sea coastline draw tourists to Egypt every year. And while most of Egypt’s residents have access to fresh water from the River Nile, transporting it to the farthest reaches of the Egyptian coast is expensive. Tourism is a significant part of Egypt’s economy, and coastal towns are looking to seawater reverse osmosis (SWRO) desalination as an option for bringing fresh water to tourist destinations.

Hydro-Solutions, a subsidiary of Express Industrial Co., is a leader in the design, manufacturing and installation of desalination plants. It is also active in the operation and maintenance of these plants. Hydro-Solutions has been supplying potable water for more than seven years to Marriot Sharm El-Sheikh Hotel in Na’ama Bay through a SWRO desalination plant. Based on its experience with low-quality welded sheet pumps that caused continuous noise and leaks, Hydro-Solutions demanded a higher quality replacement.

The Innovation Solution: Energy Recovery’s Aquabold High Pressure Pump

An evaluation of high-quality, high-efficiency pumps with casted components from global suppliers led to an obvious choice: Energy Recovery’s Aquabold 2X3X5. Using the AquaBold eliminated the annoying noise, leaks and vibration issues that Hydro-Solutions faced from its sheet metal pumps. From the casted impellers, diffusers and case, to the process-fluid lubricated internal bearings, the AquaBold has been designed from the ground up for maintenance-free operation specifically for desalination applications. Hydro-Solutions also chose to use one of Energy Recovery’s Advanced TurboCharger products to lower operation costs by recovering excess energy. Installation was easy since the pump, motor and turbocharger arrived already coupled and aligned on one common base.

The Result: Higher Quality, Less Maintenance Required and a Longer Life

The installation of the AquaBold was quick, easy and maintenance-free – adding 15 years of life to the plant. Since commissioning, it has reduced plant noise and eliminated leaks and vibrations. After almost three years of operating with Energy Recovery technologies, routine checkups have shown the AquaBold and Advanced TurboCharger are operating at above-expected efficiency with no measurable wear or need for service.

India’s meticulous water needs

Location: Udipi, Karnataka, India
Project: Udipi Thermal Power Plant
Capacity: 16,200 m³/ day
Energy Savings: 8,750,000 kWh/year* (energy savings estimates based on India’s power cost of $0.1/kWh)

The Challenge:  Indian Power Plant with Meticulous Water Needs

The Udipi 1300 MW Thermal Power Plant is a coal/gas-based power generating station located in Udipi, near Mangalore, Karnataka, India. It produces power by converting water into steam, which is then used to drive turbines. Vast amounts of the highest quality pure water are needed for the steam generation process.

The Innovation Solution:  PowerPlay with Advanced TurboCharger + High Pressure Pump

After weighing the options, contractor Triveni Engineering chose seawater reverse osmosis (SWRO) desalination as the most viable option for obtaining the highest quality pure water.  While Triveni Engineering had been offering custom made solutions to the Indian desalination industry for more than a decade, they were seeking the latest advances in energy recovery technology to increase plant efficiency. Triveni selected Energy Recovery’s Advanced TurboCharger™ (AT) due to its reliability and optimal efficiency.  Triveni also chose to configure the plant with Energy Recovery’s AquaSpire™ centrifugal high-pressure pump.  The AquaSpire pump is a single-stage, high-pressure pump ideal for medium-to-large-scale seawater- and brackish-water reverse-osmosis systems.

The AT and the AquaSpire centrifugal pump are designed to complement each other for maximum efficiency and hydraulic flexibility. A flexible solution that simplifies the SWRO system while maintaining its operational reliability, the AT is easy to install and has a compact footprint.  This winning configuration is a turnkey solution that requires minimal installation time, operator training, and plant design. With Udipi’s 16,200 m3/day plant capacity, it was of paramount importance to find the most cost-effective and energy-efficient desalination solution.

The Result: Flexibility with Cost Savings

The plant is configured with four centrifugal high-durability AquaSpire pumps and three AT TurboCharger energy recovery devices working together to give flexibility and cost-energy benefits. A total of three trains have been running since May 2010.  As a result of using our technologies, the plant went to working at 100% full capacity and year after year, saves 8,750,000 kWh of energy—increasing overall profit. More trains will be purchased for the expansion of the plant within the next two years. In fact, the client is so satisfied the setup is being showcased as a demo site for their potential customers.

Flourishing seaside Chennai with water woes

Location: Chennai, India
Project: Minjur Seawater Desalination Plant
Capacity: 100,000 m³/ day
Energy Savings: 95,484,000 kWh/year* (energy savings estimates based on India’s power cost of $0.1/kWh)

The Challenge:  A Flourishing Seaside Metropolis with Water Woes

With a growing metropolitan population of over 8 million people, Chennai is the fourth biggest population center in India after Mumbai, Delhi, and Kolkata. Historically dependent upon limited water resources, the people of Chennai must pay high costs to transport water. Meanwhile, the lakes that supply the city’s water have been rapidly depleting over the last decade due to a rapidly growing population and dwindling seasonal rains.  Chennai’s population was in desperate need to find a fresh water alternative.

The Innovation Solution: Increasing Seawater Reverse Osmosis Capacity in Region

In 2007, the water governing body of Chennai—Metropolitan Water Supply and Sewerage Board (CMWSSB)—contracted Befesa Construcción y Tecnología Ambiental (Befesa CTA) to build Chennai’s largest desalination plant. Under the agreement Befesa would design, build, own, and operate the $140 million Minjur plant for 25 years. The plant, located near Minjur just north of Chennai, would produce 237 million liters of sea water per day, supplying 100,000 m3/day (100 MLD) of desalinated water to the region.  In order to produce economically viable water and uphold environmental standards, Befesa selected Energy Recovery’s advanced PX® technology as the plant’s energy recovery device (ERD) of choice. The decision was based on the PX device’s high efficiency, low overall life cycle cost, and reliability, as well as for Energy Recovery’s industry credibility and exceptional aftermarket service expertise.

The Result: Environmentally Sustainable Drinking Water at Low Cost

The Chennai plant was built with five trains containing 23 PX devices each and has since been upgraded to a permanent intake system, running four trains and reserving the remaining train for backup. The plant is currently supplying 100,000 m3/day (100 MLD) of desalinated water to the region. To ensure that the brine from desalination is disposed of in an environmentally friendly manner, it is diluted with pure treated water before being discharged back into the sea, so the salinity does not disrupt natural habitats.

This fresh water currently reaches approximately 2 million people at a cost of just over $1 per 1,000 liters.

Energy Recovery’s energy-saving technology makes it possible for our city’s population to receive clean, reliable water at a much more competitive cost, enabling our people to live without the fear of insufficient water.“– Natarajan Ganesan, Joint General Manager, Chennai Water Desalination Company

We use Energy Recovery’s PX technology in many of our plants because the technology gives us a competitive advantage.” – Carlos Cosin, International Director, Befesa

Chennai’s second 100 MLD desalination plant, constructed by VA Tech / IDE Consortium, has been commissioned.

Egyptian water production at odds with demands to lower power use

Location: Marsa Alam, Egypt

Project: Marsa Alam Water Plant

Product Configuration: PX Pressure Exchanger 300 and VP3471 booster pump

Capacity: 1,500 m3/day

The Challenge: Water Supply Needs at Odds with Regional Demands to Lower Power Use

The shoreline of the Red Sea is a dazzling destination for tourists and locals to experience the beach and enjoy marine activities. In Egypt, the shoreline sprawls from the Suez Canal in the north, down to the southern part of the country bordering Sudan. Though most of Egypt’s population has traditionally lived in the Cairo metro area, migration trends show more and more residents are relocating to the coastlines. Given this migratory development, small coastal towns like Marsa Alam on the Red Sea now have huge demands to supply potable water to a growing population. Until recently, the Red Sea Water and Sanitation Company was operating an outmoded SWRO desalination plant and any increase in production would require a retrofit of the existing plant. In addition to the much needed plant upgrade, the Red Sea Water and Sanitation Company was tasked by regional authorities to simultaneously lower its power consumption.

The Innovation Solution: Retrofit with Energy Recovery’s PX300 and VP3471 booster pump

To solve the plant’s main issue of high power consumption, the upgrade of the old 500 m3/day plant to increase capacity to 1,500 m3/day required a high-efficiency solution. The Red Sea Company implemented two of Energy Recovery’s PX®300 Pressure Exchangers with a booster pump to optimize the plant’s energy usage. Energy Recovery’s Aftermarket Sales and Service and their proven track record of superior customer service, coupled with the maximum availability of the PX Pressure Exchangers, provided a win-win solution for the Red Sea Company.

The Result: Dramatic Energy Savings and Surge in Water Availability

By upgrading the Marsa Alam Water Plant with Energy Recovery’s PX300, the Red Sea Company witnessed immediate reductions in total power consumption at the plant. The plant is now able to run at fully upgraded capacity using only one diesel generator set instead of two: a huge contribution to the overall energy savings. Furthermore, the project return on investment and implementation was exceptional, and the Marsa Alam region now has an abundant supply of fresh drinking water for its residents.

“By retrofitting with Energy Recovery’s PX300, the return on the investment has been remarkable. The Energy Recovery support team served as expert advisers and demonstrated that we could significantly lower power consumption by two-thirds of previous levels – all without affecting water production.”
– Ragb Sobhey
Desalination Sector, Red Sea Water & Sanitation Company

Desalinated water powers China’s economic growth

Location: YuHuan, Zheijang Province, China
Project: YuHuan Power Plant
Capacity: 36,000 m³/ day
Energy Savings: US$ 2.7 million or 27 million kWh/year*
CO2 Savings: 16,000 metric tons/year**
* energy savings estimates based on China’s power cost of $0.10/kWh)
**based on Energy Recovery’s proprietary Power Model analysis.

The Challenge: Desalinated Water Powers China’s Economic Growth

As electricity production increases in China to keep pace with the nation’s rapid economic growth, power providers are caught in a bind: energy generation requires processed water, but desalinating seawater to feed power plants requires significant energy. The 4,000 MW power stations expanding China’s electrical grid in preparation for the 2008 Olympics required a seawater reverse osmosis (SWRO) plant capable of processing significant quantities of water and a careful balance of energy considerations. Beijing CNC Technology, Inc. built the YuHuan desalination facility in Zheijang Province as the largest desalination project to address the water needs of the new power generating plants. The client wanted to avoid the power drain of waste-heat processing and take advantage of reverse osmosis’ higher yields.

The Innovation Solution: PX Pressure Exchanger 220

To save energy and money, the East China Electric Power Design Institute Ministry (ECEPDI) and Beijing CNC specified Energy Recovery PX-220s for YuHuan based on its proven high efficiency and two-year trouble-free track record of the PX-220 installation at the Dalian Petrochemical Plant. The PX Pressure Exchanger® solution created for YuHuan features six trains processing 6,000 m3/day, each with six PX-220s, for a total of 36,000 m3/day.

The Result: 
Significant Energy and Cost Savings Drive Rapid Adoption

Energy Recovery’s YuHuan PX configuration, which has operated since 2006 without issue, achieves real energy transfer efficiencies up to 97% and has cut the energy required for YuHuan’s facility by 68%. Using the PX device has created an economically viable way for China’s residents and industries to benefit from the new electrical power because the PX technology recovers enough energy at YuHuan to reduce power costs by $2.7 million per year. This reduction has cut the carbon footprint of the plant by almost 260 tons of carbon dioxide each year. Because of the success at YuHuan and of the China Petrochemicals Dalian Plant, China leads the world in adoption of efficient PX solutions, with more than 90% of SWRO installations in China using Energy Recovery’s technology.

Chinese island seeks fresh water for residents and tourists

Location: Shengsi, Zhejiang Province, China
Project: Shengsi Municipal Water Company
Capacity: 1,000 m³/ day
Energy Savings: $130,000 or 1.3 million kWh/year*
CO2 savings: 748 tons CO2/year**
* energy savings estimates based on China’s power cost of $0.10/kWh
** based on Energy Recovery’s proprietary Power Model analysis

The Challenge: Island Needs Water for Residents and Tourists

Shengsi, an island in Zhoushan, China’s largest archipelago, is known for its beaches, fishing, and salt production. The area has more than 79,000 residents and hosted more than 2.7 million tourists in 2012, a number that strains the island’s minimal natural water supply. Before constructing a desalination plant, daily water flow and availability could be severely limited especially during drought season. Though expensive, emergency fresh water was sometimes brought by boat (only during good weather), and the inhabitants needed a more reliable source of affordable, clean water. And because power is so costly for the Zhoushan archipelago, the Shengsi Municipal Water Company needed a desalination plant that operated as efficiently as possible.

The Innovation Solution: 
PX Pressure Exchanger

When Hangzhou Torch designed and built a seawater reverse osmosis (SWRO) plant for Shengsi in 2001, the plant included Energy Recovery’s PX® 60 that has now been in operation for more than 60,000 hours (it is one of Energy Recovery’s oldest and longest running PX solutions, operating without maintenance or downtime for more than twelve years). On a second installation, Shengsi Municipal Water tried a competitor’s energy recovery device on a 600 m3/day train but quickly decommissioned it. All subsequent installations at Shengsi’s SWRO plant (1,000 m3/d in 2004, 4,000 m3/d in 2005, and 4,000 m3/d in 2012) have been equipped with Energy Recovery’s PX-140s and PX-220s, all of which operate at full capacity and efficiency. Thanks to unparalleled longevity with the PX, it may be the one part of the SWRO plant that will never need replacement.

The Result: 
Twelve Years of Operation Without Maintenance

A reliable source of clean water in Shengsi has helped the residents, tourists, and island economy. After checkups in 2008 and 2010, Energy Recovery and Shengsi Municipal Water Company were pleased that the maintenance-free, lifetime design of the PX® has yielded virtually no wear to the device, and an estimated $1.5 million savings over its twelve years of operation. Shengsi’s PXs are still operating with maximal efficiency and are recycling 1.3 million kWh per year to keep the cost of water low enough to supply up to 80% of the island’s water needs, and will continue to recapture and recycle fluid-flow energy for the remaining life of the plant.

“The performance of the devices has exceeded our expectations for reliability and energy savings.” – Hangzhou Torch

China’s residents compete for fresh water access

Location: Qingdao, Shandong Province, China
Project: Qingdao BAIFA Seawater Desalination Plant
Capacity: 100,000 m³/day
Energy Savings: US$ 9.6 million or 96 million kWh/year*
CO2 savings: 56,000 tons CO2/year**
* energy savings estimates based on China’s power cost of $0.10/kWh
** based on Energy Recovery’s proprietary Power Model analysis

The Challenge
: Industry Competing with Residents for Access to Fresh Water

In the vibrant seacoast city of Qingdao, China, a diverse population of over 8 million people shares space and resources with rapidly growing industry. The pressing need for a larger municipal water supply led government leaders to commission a seawater reverse osmosis (SWRO) water treatment plant. In choosing Abengoa Water, which has built huge reverse osmosis (RO) plants on other continents, the Municipality of Qingdao sought the expertise of a company that knows how to design and build massive water treatment plants that bring huge quantities of drinking water to urban populations.

The Innovation Solution
: PX Pressure Exchanger 260

Abengoa Water knew from its RO work on several continents that recovering and recycling energy was paramount to keeping water affordable, a consideration especially important given the huge flow capacity needed at Qingdao. Because Energy Recovery’s technological solutions have minimized the cost and energy footprints of their six other mega-projects, Abengoa Water wanted Energy Recovery’s PX Pressure Exchanger® technology to make processing more productive, profitable, and environmentally cleaner.

The Result: 
Drinking Water for Half a Million People

The PX supplied Qingdao’s RO plant with the potential of saving 96 million kWh per year and of cutting 56,000 tons of CO2 emissions with Energy Recovery’s industry-leading technology that recaptures the reusable energy from fluid flows and pressure cycles. The Qingdao processing plant will bring fresh water to up to 500,000 residents of Qingdao. Energy Recovery’s PX trains make desalination more affordable and sustainable by harnessing reusable energy at high efficiency with no downtime. “Abengoa continues to work with Energy Recovery to implement its innovative PX devices to significantly reduce the life cycle costs of the desalination process,” said Carlos Cosín, CEO of Abengoa Water. “We continue to be impressed with the reliability, efficiency and overall performance of its PX technology. We anticipate similar success in the Qingdao facility.”

BVI dependent on reliable fresh water for GDP growth

Location: Tortola Island, British Virgin Islands
Project: Biwater Tortola

Product Configuration: PX Pressure Exchanger and AquaBold high pressure pump

Capacity: 10,400 m³/ day

The Challenge: British Virgin island dependent on reliable freshwater for GDP growth

Tortola is the largest British Virgin island in the Lesser Antilles with an approximate population of 24,000 residents. 92% of its Gross Domestic Product (GDP) comes from tourism where close to one million people visit the island every year. As with many island nations without natural aquifers, Tortola must produce all of its drinking water and demand is constantly high. Historically the island has supplied fresh water to residents and visitors through seawater reverse osmosis desalination, but current facilities in operation are deteriorating and this is having a deleterious effect on the island’s environment and marine life. In order to meet the island’s growing demand for fresh water supply, Biwater was contracted to design a new, environmentally-sound desalination facility to provide high-quality fresh water to the island alongside wastewater treatment facilities.

The Innovation Solution: The PowerPlay for faster time to market with superior energy savings

Biwater selected Energy Recovery’s PowerPlay integrated solution: PX Pressure Exchanger® 220 and the AquaBold high pressure pump. In island nations such as Tortola where power costs are high, Biwater chose the PX energy recovery device because it has the fastest payback than any other ERD in the market and allows the company to focus on delivering the highest quality water at the lowest price to the end user. In summary, by choosing the PX and AquaBold PowerPlay solution, Biwater is able to streamline the complex process of moving the Tortola plant from concept to operation. By combining the PX and the AquaBold, the Biwater Tortola project will enjoy faster deployment, longer life, and greater uptime.

The Result: Highest quality water for island’s biggest industry

The Biwater Tortola plant will be able to supply residents and tourists with highquality, affordable potable water. When operating at full capacity, the Tortola plant will produce 10,400m3 of treated water per day, and with Energy Recovery’s PowerPlay solution, the energy saved will be an estimated 9 million kWh per year – or the equivalent to taking 1,300 cars off the road. In addition to the new desalination facility, Biwater is also providing wastewater treatment facilities that will help better protect marine life in the vicinity. Once the desalination plant is online, the facility will boast the highest efficiencies possible with the Energy Recovery PowerPlay.