Middle East/North Africa

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.

Energy Recovery Systems in Acid Gas Recovery Plants


Authors (Energy Recovery): Chinmay Deshpande, Matthew Pattom, Dung Tran
Authors (Saudi Aramco): Rehan Farooqi, Mohammad Buali, Abdullalh A. Al-Ghamdi

Four sets of hydraulic turbocharger based energy recovery systems (2000 hp each) were successfully designed, manufactured, tested and commissioned for Acid Gas Recovery plants (AGR) in Saudi Arabia. The hydraulic turbocharger consists of a liquid phase turbine runner and a pump impeller mounted in a back‐to‐back configuration on a common rigid shaft, in a single seal‐less casing. The shaft is supported by process lubricated hydrodynamic radial and axial (dual‐acting) bearings of non‐metallic construction. The turbine side extracts wasted pressure energy from the rich amine and along with a series of throttle, auxiliary and bypass valves, controls the level in the absorber. The pump side boosts the lean amine solvent to the absorber. Such a design provides major advantages compared to a conventional configuration of a reverse running pump‐as‐turbine coupled to a pump. These advantages include a compact single stage hydraulic design (as opposed to a multi‐stage design for a reverse running pump), smaller footprint, higher efficiency, absence of mechanical seals & associated support system, absence of lubrication oil system as well as simpler control.

Several complex design and testing challenges were overcome through development of novel design features and incorporation of provisions in a highly specialized test loop. Some of the unique experiences are shared in the paper. The seal‐less design of the turbocharger with no exposed rotating or bearing parts presented testing challenges such as determination of shaft power, individual pump side and turbine side performance and efficiencies; measurement and validation of axial thrust & axial position; as well as monitoring & control of bearing performance parameters. The test loop was engineered to operate the hydraulic turbocharger through its testable operating range with provisions to measure, control and monitor all the needed parameters. Testing was performed using water with viscosity 2.5 times lower than the operating fluid. This implied suitable modification to the design, monitoring and controlling of process‐lubricated bearings along with the internal system during testing to account for the change in viscosity. Data was evaluated to conduct root cause analysis of apparent bearing failures such as rub marks and to eliminate root causes by improving the manufacturing method to reduce misalignment & also using non‐metallic bearings.

Four identical units were built and completed successful Factory Acceptance Tests (FAT) in early 2018. The turbochargers achieved & surpassed the pump side rated requirements of 2148ft of head at 2820 gpm, at a rated speed of 8000 rpm, as part of the FAT. All the units were installed & commissioned in early 2020 by the End User. Each unit is part of 4×50 configuration – which includes the turbocharger and three circulation pumps running in parallel. The paper will provide details about the commissioning effort of the turbocharger units in the field, and their operating experience over a period of one year.

White Paper: Keys to High Efficiency, reliable performance and successful SWRO operations

Isobaric energy recovery devices (ERDs) have attained nearly universal acceptance by the seawater reverse osmosis (SWRO) desalting world. These devices are operating in the largest SWRO trains in the world and continue to be an integral component in small, containerized systems. Systems incorporating isobaric ERDs are being installed and supported on all seven continents. This has lead to an accumulation of a wealth of knowledge based on practical operating experience.

Waste-to-energy in amine gas sweetening with the IsoGen: an innovative approach to recovering hydraulic energy

As the demand for clean energy throughout the world continues to grow, the need for disruptive technologies to help natural gas producers overcome the effects of rising operational costs and adhere to more stringent regulations will become increasingly prominent. Energy Recovery’s flexible IsoGen® skid-mounted system provides natural gas producers with a way to recover otherwise lost pressure energy by replacing the contactor LCV with a liquid phase turbogenerator within their amine treating cycle. This white paper discusses an installation in the Kingdom of Saudi Arabia and showcases where this technology will help transform what was once considered wasted energy into a reliable source of power.

Upgrading ERDs within an operating desalination plant in Israel

The Palmachim Desalination plant is one of the largest seawater reverse osmosis (SWRO) desalination plants in Israel with a capacity of 120,000 cubic meters per day. Built by the Via Maris Desalination Ltd. consortium, the plant consists of six (6) parallel SWRO trains, each with a permeate production capacity of up to 20,000 cubic meters per day. In addition to its high-capacity SWRO trains, the Palmachim plant is unique because it was designed to be easily turned on, off or slowed down. Electricity tariffs in Israel are significantly higher during the day than at night with a cost ratio of up to six to one. The plant’s flexibility allows the operators to minimize energy consumption during the day when the power cost is high by shutting down up to 85% of the plants capacity.

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.

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.

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