Asia Pacific (APAC)

First Ultra PX for Wastewater Treatment Yields Savings with High Performance

Sinochem Case study cover

This recent case study, which focuses on the first site to commission an Ultra PX 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 Ultra PX for the ultra high-pressure reverse osmosis stage to capture energy otherwise wasted in the wastewater treatment process.

Energy Recovery in China

China has been turning to seawater reverse osmosis (SWRO) as a way to ease the severe stress on fresh water resources, and ninety percent of Chinese desalination plants use Energy Recovery’s technology to harness fluid flows and pressure energy. Watch this video to hear experts in the Chinese desalination industry talk about their experience with Energy Recovery over the past ten years.

Chinese version available


面对日益严峻的水资源短缺,中国各水利机构与各大全球水处理公司建立了合作伙伴关系,致力于建造 中国现今最大的反渗透海水淡化厂。美国能量回收公司始终为主要的海水淡化厂提供高效领先的能量回收设备,并 在中国拥有90%的市场占有率,每日供水估约50万立方米。

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


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.

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.

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.”

China’s mega-desalination plant experience

The gap between fresh water supply and demand is steadily widening in the People’s Republic of China, home to approximately 20% of the world’s population. Demand for water supplies continues to grow as both personal and industrial consumption surges. Underground water resources, meanwhile, are already overused and badly polluted, and the deep wells now being drilled are frequently tapping into arsenic-rich aquifers, posing safety risks to as much as 30% of the country’s population.

To help combat shortages, desalination, in the form of sea water reverse osmosis (SWRO), has become an integral part of China’s long-term water management strategy. Historically used on a small scale, desalination is now becoming more widely accepted for large-scale water production, particularly in highly populated coastal areas. In recent years, China announced plans to grow its desalination capacity to 2.2 million m3/d (581 million GPD) by 2015, and Chinese water authorities formed partnerships with global water treatment companies to construct large SWRO facilities.

So far, this initiative has resulted in the construction of the nation’s two largest SWRO plants — the Qingdao and Tianjin Dagang SWRO desalination facilities. Designed, constructed and operated by Abengoa and Hyflux, respectively, the two plants together add 200,000 m3/d (52 MGD) of installed capacity to China’s water network. Half of that comes from the Tianjin facility, which began delivering desalinated water to the northern China city’s industrial zone in July 2009. Three years later in eastern China, Qingdao’s municipal water supply began receiving a comparable amount of water from the new SWRO plant there. Both of these state-of-the-art facilities use the latest desalination technologies, including rotary-type isobaric energy recovery devices (ERD).

By considering not only initial capital expenses, but also operational and maintenance expenses, material alternatives and expected uptime of the Energy Recovery System (ERS), these plants demonstrate how sustained long-term energy efficiency can be achieved in large-scale SWRO plants. By displaying proper system design and energy recovery device (ERD) selection, both mega-plants provide an excellent model for future desalination projects in China.