Keterangan :

DESALINATION by NATURAL PRESSURE ©

Our System

The main merit of the natural pressure seawater desalination system lies in having combined apparently scarcely-related activities with the aim of transforming seawater into fresh water at a price that is starting to approach that of rainwater.

Despite its innovative conception, the System does not use any type of technology that not bee industrially proven in highly different fields, given that reverse osmosis membranes, filters, impulsion pumps and high-pressure pipelines all form part of everyday life in an infinite number of processes. With regard to the efficiency of underground shafts and wells, mining has been on important activity for several centuries. At the present time, underground works at great depth are also used to accommodate hydroelectric power plants and waste storage facilities.

Great energy savings

Until today, desalination had never constituted a competitive source of fresh water supply due to the fact that the most effective systems operating consisted of pumping seawater at high pressure through reverse osmosis membranes, involving a high energy cost and high maintenance cost of the installation.

The System is a radical improvement on the performance of conventional desalination plants, as it replaces the complex mechanical pumping system with a column of seawater. Every ten metres of a water column is the equivalent of one atmosphere of pressure, and it this natural pressure and not electrical energy that provides the pressure necessary for the reverse osmosis membranes to work.

The best way of taking advantage of this pressure is to bore in the ground, not far from the coast and in soils of a competent geology witch can easily be located in most coastal zones, a shaft at whose bottom the reverse osmosis membranes are installed along the length of a horizontal gallery.

The seawater exerts its pressure through vertical pipelines bolted to the perimeter of the shaft, and when reaching the reverse osmosis membranes these act in the same way as in a traditional plant, dividing the salt water into two flows: one of fresh water and another of doubly salty water.

The doubly salty water passes the membranes without losing hardly any pressure. By means of a parallel pipeline, and in accordance with the law of communicating vessels, it is returned to the sea under its own residual pressure, without the need for any pumping, since the plant is designed to compensate for load losses. The fresh water is thus left ready for use in the underground chamber.

Any urban agricultural or industrial community close to the sea is therefore in a position to be provided with a cheap source of purified fresh water, from its own inexhaustible aquifer of excellent quality.

To raise the drinking water to the surface the same energy is required as in the pressurized pumping of traditional systems, but as it only has to lift the fresh water, which is less than half of the total and is less dense than seawater, the System consumes 45 % less energy than a conventional plant.

The constant pressure of the water column also makes it possible to guarantee the stability of the desalination process energy consumption, as well as its instant starting or stopping, and it can thus adapt to the most favourable electricity tariff in order to further reduce energy costs.

Ease of operation and savings in maintenance

Conventional desalination plants use turbo pumps that are obliged to work with highly corrosive seawater and brine solutions. The System does not need sophisticated mechanical elements but operates with simple impulsion pumps, the vast majority of it only come into contact with fresh water.

The lower the number of moving elements in a particular industrial activity, the proportionally lower the number of operatives and maintenance costs.

The water column, which always exerts an identical and constant pressure, guarantees start up an simple operation without the need for complicated control systems.

The energy saving together with the saving due to the easy handling and maintenance of the installation allows for a lower production cost.

The System provides a longer useful lifetime of the installations; which will continue to operate in a perfect state of conservation for more than thirty years.

Environmental benefits

As well as saving energy, which is the most important of its environmental benefits, the Natural Pressure Desalination System presents the added advantages of a lower visual impact, important space savings at ground level and not producing acoustic contamination, since it does not use turbo pumps. These three aspects make the System an especially interesting option in locations close to housing, tourist facilities and natural sites that require special protection, where and price are high and aesthetic values a priority.

Finally, it should be noted that the doubly salty water that is returned to the sea is clean and its temperature unaltered, since it does not come into contact with any mechanical element, and thus does not affect the local flora or fauna, acting in the same way as the clouds which only raise the fresh water an leave the salt in the sea.

High capacity of the plant

Once the access shaft has been constructed, it is equally valid for a plant of 50.000 cubic metres per day capacity or 800.000 cubic metres per day, depending on the number and diameter of pipes that are used.

This initial investments which is identical whatever the future production volume, nevertheless becomes a great advantage as the production increases, since the investment ratio per cubic metre of capacity, as well as the time for the implementation of extensions, is significantly reduced. The plant is designed to adapt to the requirements of the demand, permitting quick extensions to meet needs during the decades of its use.

From 100.000 m3 per day, the investment cost equals that of conventional plants, and for greater volumes becomes proportionally less, in favour of our System, in addition to the fact that the plants useful lifetime will always be twice as long.

Large amounts of water for agriculture, urban consumption and industrial development can be feasible and affordable with the endless source offered by this system: the sea.

The Feasibility Study of this technology has been undertaken by a Spanish Engineering Company, shared by the more important electric companies in our country, present in all areas of engineering.