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Desalination Directory

a Thesis on the subject pdf (4.8 mb)

Aqualyng enables constant supply of fresh drinking water, using technology that tenders economical solutions even in rural areas. Our desalination plants can be installed close to end users. Decentralised solutions reduce distribution cost, minimise environmental damage, enable water intake from saltwater wells and are easily adapted to suit local building tranditions.

Low energy consumption
Aqualyng’s desalination process uses membrane filter based on the reverse osmosis principle. Our proprietary energy recovery process recycles as much as 98.5% of the energy. Moreover, this advanced system consumes some 2 kWh per cubic metre of fresh water, which is considerably less than traditional solutions. Aqualyng's energy recycling process gives low operating cost and improved operation condition for the membranes.

Aqualyng's solution secure low investment cost and low operation cost.

Aqualyng Systems

The energy consumption rates for a conventional system (with Pelton turbine as energy recovery device) are around
3 - 4.5 kWh/m3 of fresh water produced from Atlantic seawater. The energy consumption of desalting Atlantic seawater
at 20oC temperature using the Aqualyng system is 2.0 kWh/m3 of fresh water produced.

Compared to conventional systems with turbines, the Aqualyng system results in a saving of minimum 1.5 kWh/m3. However, the system becomes more advantageous as the feed water salinity incre-ases and savings of 2-3 kWh/m3 is, for example, to be expected for most cases of Red Sea and Arabian Gulf applications.

The AqualyngTM system uses the brine energy in a special equipment, called the Recuperator, to pressurise seawater to the same pressure as the brine. The process is actually a pump, of the reciprocating principle, hydraulically driven by the brine.
The capacity of this "pump", in terms of flow and pressure, is the same as the brine stream.

There are no moving parts in the Recuperator, as opposed to other pressure recovery devices, and this increases the durability of the system.

A small booster pump is required to compensate for the pressure drop in the membranes and the piping system. This booster pump increases the pressure of the pre-treated seawater that has gone through the "pressure recuperator" up to the operating pressure required at the membranes inlet. As the process delivers seawater at the same flow rate as the brine rejected by the RO membranes, then the capacity of the high-pressure pump will be equal to the fresh water produced by the membranes.

This means that with a system recovery rate of 40%, 60% of the feed water is delivered by the Recuperator system and only 40% from the high pressure pump.

In a conventional SWRO desalination system, all feed water has to go through the high-pressure pump which only has a modest efficiency, 70-85%, dependent on type and size. The Recuperator has an efficiency of around 98% and this is where the big difference lies.

The Recuperator

The AQUALYNG - energy recovery system is a work exchanger that uses the saline-reject (brine) from the membranes to pressurise pre-treated seawater in a sequential process.

The whole system uses pairs of duplex stainless steel vessels that work alternatively
in a compression and decompression-discharge sequence. Pre-treated seawater comes from a pressurised feeding tank that keeps a constant flow and pressure into
the system. One of the vessels is under high-pressure by the brine and displacing seawater while the other is filling up with low-pressure pre-treated seawater from
the top and draining the reject at the bottom.

The pressurised seawater goes into the membrane train via a booster pump. This pump compensates the head losses across the membrane elements and the piping system, which are around 2-3 bar.

The whole sequence is accomplished by the operation of a set of several duplex stainless steel valves actuated by a hydraulic system and automatically controlled by
a PLC platform, thus resulting in a continuous flow of seawater at high pressure into
the membranes.

Download the Recuperator animation here >>

Aqualyng wins contract to Build, Own, Operate 114 000 m3/day desalination plant in Karachi, Pakistan

Vanvikan, Norway, June, 26th, 2007
Aqualyng, leading supplier of desalination plants based upon reverse osmosis technology, secures breakthrough project in Karachi. A contract has been signed between Karachi Water & Sewerage board and Aqualyng to build, operate and produce 114 000 m3 of potable water to Karachi. The city of Karachi has the past years experiences severe water shortage, and the establishing of this mega plant is the first step in the process of utilizing desalination to reduce the water shortage.

The agreement includes a dedicated power plant and distribution piping, and will be completed in 24 months. The plant will be located in the Hawks Bay area, where the land has been made available by the City District Government Karachi (CDGK) .Included in the agreement is the option of increasing capacity to 228 000 m3/day.
The signing of this major project follows Aqualyngs recent success in Pakistan with the signing of an MOU for 2x10.000 m3/day in Gwadar, Balochistan.

More water - less energy
Aqualyng AS is a Norwegian company specialized in delivering desalination plants for production of all qualities of water. Aqualyng AS develops, fabricates, sells, operates and services desalination plants, and has installed successful plants since 1999. The Aqualyng plants are cost-effective solutions based on the patented energy recovery system, the Recuperator, and standardized modules.

Aqualyng AS is owned by Aqualyng Holding, a company dedicated to financing water contracts globally. Aqualyng Holding is established in Norway and Dubai, and has the financial strength to participate in large international desalination projects.

For more information, please contact:

Christian Wee, Sales Director
Aqualyng AS

Eric Jankel. CEO
Aqualyng Holding


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