[go: up one dir, main page]

WO1999006323A1 - Method and plant for desalting seawater exploiting hydrostatic pressure - Google Patents

Method and plant for desalting seawater exploiting hydrostatic pressure Download PDF

Info

Publication number
WO1999006323A1
WO1999006323A1 PCT/IT1998/000210 IT9800210W WO9906323A1 WO 1999006323 A1 WO1999006323 A1 WO 1999006323A1 IT 9800210 W IT9800210 W IT 9800210W WO 9906323 A1 WO9906323 A1 WO 9906323A1
Authority
WO
WIPO (PCT)
Prior art keywords
water
fact
ocean
plant
underwater
Prior art date
Application number
PCT/IT1998/000210
Other languages
French (fr)
Inventor
Francesco Maria Piccari
Fulvio NOVELLI
Original Assignee
Francesco Maria Piccari
Hardy Andre
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Francesco Maria Piccari, Hardy Andre filed Critical Francesco Maria Piccari
Priority to AU86453/98A priority Critical patent/AU8645398A/en
Publication of WO1999006323A1 publication Critical patent/WO1999006323A1/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/02—Reverse osmosis; Hyperfiltration ; Nanofiltration
    • B01D61/10—Accessories; Auxiliary operations
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A20/00—Water conservation; Efficient water supply; Efficient water use
    • Y02A20/124—Water desalination
    • Y02A20/131—Reverse-osmosis

Definitions

  • the present invention relates to a method for desalting sea water, that exploits the positive gradient existing between the hydrostatic pressure that builds up at oceanic depths and the osmotic pressure exerted by salt water onto an interface which is made of a semi-permeable membrane.
  • the term "ocean” means to refer to any basin on whose floor pressures are in ranges over 20 fold that of the atmosphere.
  • the present invention further relates to a plant which is capable of accomplishing said method.
  • said method provides for the employment of desalting plants which are completely underwater, and are further statically hanging from floating islands, at depths which are higher than 200 metres, preferably 1000 metres, where natural pressures are in the range of 100 atmospheres, avoiding to get the semipermeable membranes to undergo the fatigue that derives from pressure variations.
  • a third drawback derives from the fact that, as the water to be filtered is taken from near the coasts, it is necessary to provide for ⁇ _he disposal of inert materials, which are themselves dispersed by the seawaves, and of all biological materials in the form of suspensions, making production plants more complex and increasing their costs.
  • European Patent EP 0 764 610 discloses a method for desalting sea water wherein seawater is drawn from near the coast and it is further forwarded to the terra firma , to such an altitude that is sufficient to generate enough pressure to substantially give way to an inverse osmosis phenomenon, so that salt water gets to be separated into fresh water and brine.
  • Such a solution which makes the most of geomorphological slopes solves the problem that we mentioned first, as it avoids to get the membranes to undergo a fatigue, as it resorts to the use of a constant hydrostatic pressure, but on the other hand it does net even approach a solution to the other problems, as it draws salt water from near the coast and gives way to a brine accumulation on the terra firma .
  • Aim of the present invention is that of finding a one solution that overcomes all of the drawbacks associated with the prior art, also reducing the overall costs associated with the production of desalted water.
  • Such an aim has been accomplished according to the present invention, by providing a method and a plant related thereto for seawater desalting, which is to be located under seawater level and is capable of exploiting the hydrostatic pressure that builds up at an at least 250 metre depth on one side of the filter membrane, in order to overcome the osmotic pressure which is characteristic of salt water itself, whereas the other side of the membrane is kept at atmospheric pressure, whilst pumping operations are only reduced to those related to the fresh water obtained from the filtration.
  • a desalting method is provided, as well as the plant and equipment thereto related, which are themselves based on the employment of semipermeable membranes and supply fresh water witnout tne ensuing production of residues to be disposed of on the ground, and without the risk of crystallisations that clog the semipermeable membranes.
  • the plant, equipment and method object of the present invention aimed at accomplishing seawater desalting precisely make use of ocean water and not seawater.
  • a substantial reduction in the overall production costs is accomplished, by providing for the tying of the underwater plant and equipment to a floating island whose surface is covered with solar cells, in order to exploit photovoltaic energy.
  • a first reason is the smaller chlorine content.
  • a second reason is its lower turbidity.
  • a third reason is its lower temperature.
  • a fourth reason is its smaller biological content.
  • a fifth reason is its greater hydrostatic pressure.
  • a sixth reason is the lack of crystalline residues to be disposed of.
  • the present invention makes it possible to perform ultrafiltration, which a sea water (and not ocean water) plant and equipment cannot certainly accomplish using an industrial process of the same type.
  • attention is drawn to the two pressures that build-up upstream and downstream from the semipermeable membranes.
  • the pressure gap between the two faces of each of the filtering membranes must have a value equalling one hundred atmospheres. Said pressure gap is accomplished according to the prior art as the gradient between 101 absolute atmospheres and 1 absolute atmosphere.
  • An absolute pressure equalling one atmosphere is the static pressure which is normally exerted by the environment.
  • a 100 atmosphere relative pressure can be accomplished in two different ways, that is naturally and artificially.
  • a natural system that exerts a 100 atm relative pressure can be better defined by referring to the hydrostatic pressure that builds up 1000 metres below sea level .
  • Fig. 1 is a schematic view of a pilot plant for the production and distribution of drinkable water, transformed from ocean water, where underwater chambers are statically hanging from floating islands;
  • Fig. 2 shows in particular an underwater chamber with semipermeable membranes.
  • Fig.3 is a cross section view of a membrane. With reference to the above drawings, a series of suspended and self-supporting chambers 2 at a 1000 metre depth is fixed.
  • Each chamber 2 is provided with three communicating openings 4, 6 and 8.
  • the first of said openings 4 is connected with a vertical chimney 10 which suitably desurfaces from the ocean and is apt to transfer atmospheric pressure into the volume of the underwater chamber which is located at a 1000 m depth.
  • the second opening 6 is stoppered by semi-permeable membrane blocks 12 which have an outer face E that is subject to a 100 atmosphere pressure, and an inner face I which is only subject to the atmospheric pressure transferred by chimney 10, and a slight depression is further created on it in order to compensate for the weight cf the one Km long air column that overlies it.
  • semi-permeable membrane blocks 12 which have an outer face E that is subject to a 100 atmosphere pressure, and an inner face I which is only subject to the atmospheric pressure transferred by chimney 10, and a slight depression is further created on it in order to compensate for the weight cf the one Km long air column that overlies it.
  • the third opening 8 is connected with a vertical conduit 14 that itself reaches the ocean surface and is provided with pumps that draw the drinking water which has been filtered into the chamber located underwater from the second opening 6, in such a way as to keep the water level constant inside the underwater chamber.
  • the water surface inside the chamber has in fact to result to be below the lower edge of the membrane, and it is net meant to ever rise to a level that is higher than said lower level of the membrane.
  • a system of buoys 15 which are suitably structured, sized and joined to each other, and carrying a platform or surface 16 mainly covered with photovoltaic cells, whose amount is proportional to the power necessary for the transport of the drinking water produced to the area where it is bound to be used.
  • Said area is horizontally far from the floating buoys 15 at the zenith of the underwater plant which is suspended in the ocean water. Distances along the sea horizon may be in the kilometre range, between 20 and 30 or even less according to the specific underwater morphology.
  • the drinking water pipes are located underwater and they are suspended above the continental platform; they are further allowed to crop up and desurface in safe areas that are very close to the coasts. From the coasts and down to the areas where the water is used, drinking water is distributed along underground pipes that may be even much longer than the distance separating the buoys from the coast.
  • K is a coefficient characterising the semipermeable membrane
  • S is the membrane surface expressed in square metres
  • p is the osmotic pressure that builds up from ocean water
  • P is the hydrostatic pressure of ocean water
  • Q is the Kg/s drinking water flow rate and it refers to the drinking water produced. Acting on the size of the surface, and estimating the pressure gap in the order of 75 Kg per square metre, the flow rate results to be:
  • Drinking water production has an investment and production cost per cubic metre of drinking water obtained. Said cost depends on the industrial process which is resorted to and it is proportional to the costs which are related to the power needed. According to the present invention there is found to be a drop in the costs related to the power that is necessary for the production of drinking water at ocean depths as there is no exploitment of temperature, rather of hydrostatic pressure which is naturally available at those depths. The drop in the costs for the production of a cubic metre of drinking water makes it possible to produce large amounts of drinking water at very reduced costs, and it further paves the way to the fight agains desertification.
  • the energy that is necessary for pumping is electric power.
  • the cost of the electric power necessary for the distribution of the product is made to drop, as it was already stated, resorting to photovoltaic energy.
  • the cost of photovoltaic energy can be categorised into the investment cost for the solar cells and the cost related to power production.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Water Supply & Treatment (AREA)
  • Nanotechnology (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Other Liquid Machine Or Engine Such As Wave Power Use (AREA)
  • Pressure Vessels And Lids Thereof (AREA)
  • Powder Metallurgy (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)

Abstract

The invention relates to a method and a plant for seawater desalting which is to be located under seawater level and is capable of exploiting the hydrostatic pressure that builds up at an at least 250 metre depth on one side of a semipermeable filter membrane, in order to overcome the osmotic pressure which is characteristic of salt water itself, whereas the other side of the membrane is kept at atmospheric pressure, whilst pumping operations are only reduced to those related to the fresh water obtained from the filtration.

Description

METHOD AND PLANT FOR DESALΗNG SEAWATER EXPLOIΗNG HYDROSTAΗC PRESSURE
DESCRIPTION
The present invention relates to a method for desalting sea water, that exploits the positive gradient existing between the hydrostatic pressure that builds up at oceanic depths and the osmotic pressure exerted by salt water onto an interface which is made of a semi-permeable membrane. The term "ocean" means to refer to any basin on whose floor pressures are in ranges over 20 fold that of the atmosphere. The present invention further relates to a plant which is capable of accomplishing said method.
In particular said method provides for the employment of desalting plants which are completely underwater, and are further statically hanging from floating islands, at depths which are higher than 200 metres, preferably 1000 metres, where natural pressures are in the range of 100 atmospheres, avoiding to get the semipermeable membranes to undergo the fatigue that derives from pressure variations.
The use of semipermeable membranes in fresh water production plants for the benefit of human beings and animals has been known for a good while. There have indeed resulted to exist for about a decade a number of plants of this type through which up to 300000 m3 fresh water αay are μro uced, -»j c J_ α. t — u^ that reach 70 Kg force/cm2 (=70 Newtons) . There are several chemical formulae that identify the structures of said semipermeable membranes, whereas the types of supports are about 100. Membranes have got a thickness that is in the range of microns, whereas supports have got thicknesses in the centimetre range. Water filtration through semipermeable membranes has been explained so far thanks to three different mechanistic hypotheses, each of which has not found any certain corroboration. Therefore, currently research is taken forward empirically and plants are optimised on a trial and error basis.
However, the different practical solutions found so far do not turn out to be satisfactory for different reasons .
One of the worst drawbacks is the fact that pressure is generated dynamically, therefore it is necessarily subject to variations which force the membrane used to suffer from fatigue, m so doing negatively affecting the average life span of usefulness for filtration. Furthermore all filtration plants used nowadays yield to the accumulation of the salts that precipitate during the process on the terra firma , because of the saturation of the solution which has undergone treatment, causing further problems related to waste disposal and pollution.
A third drawback derives from the fact that, as the water to be filtered is taken from near the coasts, it is necessary to provide for τ_he disposal of inert materials, which are themselves dispersed by the seawaves, and of all biological materials in the form of suspensions, making production plants more complex and increasing their costs.
European Patent EP 0 764 610 discloses a method for desalting sea water wherein seawater is drawn from near the coast and it is further forwarded to the terra firma , to such an altitude that is sufficient to generate enough pressure to substantially give way to an inverse osmosis phenomenon, so that salt water gets to be separated into fresh water and brine. Such a solution which makes the most of geomorphological slopes, solves the problem that we mentioned first, as it avoids to get the membranes to undergo a fatigue, as it resorts to the use of a constant hydrostatic pressure, but on the other hand it does net even approach a solution to the other problems, as it draws salt water from near the coast and gives way to a brine accumulation on the terra firma .
Aim of the present invention is that of finding a one solution that overcomes all of the drawbacks associated with the prior art, also reducing the overall costs associated with the production of desalted water.
Such an aim has been accomplished according to the present invention, by providing a method and a plant related thereto for seawater desalting, which is to be located under seawater level and is capable of exploiting the hydrostatic pressure that builds up at an at least 250 metre depth on one side of the filter membrane, in order to overcome the osmotic pressure which is characteristic of salt water itself, whereas the other side of the membrane is kept at atmospheric pressure, whilst pumping operations are only reduced to those related to the fresh water obtained from the filtration.
According to a first aspect of the present invention, a desalting method is provided, as well as the plant and equipment thereto related, which are themselves based on the employment of semipermeable membranes and supply fresh water witnout tne ensuing production of residues to be disposed of on the ground, and without the risk of crystallisations that clog the semipermeable membranes.
According to a second aspect of the invention, the plant, equipment and method object of the present invention aimed at accomplishing seawater desalting precisely make use of ocean water and not seawater.
According to a farther aspect of the present invention, a substantial reduction in the overall production costs is accomplished, by providing for the tying of the underwater plant and equipment to a floating island whose surface is covered with solar cells, in order to exploit photovoltaic energy.
It results to be quite pertinent to emphasize the fact that the current state of the art provides for the transformation of salt water into fully drinkable water which is allotted to any type of use, but according to the prior art, seawater ana not ocean water i used as starting material. Sea water and ocean water have not got the same properties or, if they do they are not present in them to the same extents.
The comparison between sea and ocean water in terms of their purifying, results in an objective preference to be absolutely granted to ocean water, for many important reasons.
A first reason is the smaller chlorine content. A second reason is its lower turbidity. A third reason is its lower temperature. A fourth reason is its smaller biological content. A fifth reason is its greater hydrostatic pressure. A sixth reason is the lack of crystalline residues to be disposed of.
Experimentally, it was verified that a cubic metre of sodium chloride and magnesium chloride solution in water, at a temperature of 20°C, with a sodium content which is 8.3 times higher than its magnesium content and with an average salinity ranging around 35 kilograms per tonne, exerts an osmotic pressure equalling 25 times the atmospheric pressure, which itself equals hydrostatic pressure at a depth of approximately 250 metres, that is in waters that are of the ocean type, according to hydrological science.
These data mean that there is no sea where it is possible to exploit the hydrostatic pressure on its floor as a function of inverse osmotic pressure, which is suitable to make it possible to perform ultrafiltration.
The present invention makes it possible to perform ultrafiltration, which a sea water (and not ocean water) plant and equipment cannot certainly accomplish using an industrial process of the same type. In order to shed further light onto the inventive concept of the present invention, attention is drawn to the two pressures that build-up upstream and downstream from the semipermeable membranes. In order to obtain fresh water from salt water at a 35 %o concentration (w/v) , the pressure gap between the two faces of each of the filtering membranes must have a value equalling one hundred atmospheres. Said pressure gap is accomplished according to the prior art as the gradient between 101 absolute atmospheres and 1 absolute atmosphere.
An absolute pressure equalling one atmosphere is the static pressure which is normally exerted by the environment. A 100 atmosphere relative pressure can be accomplished in two different ways, that is naturally and artificially.
A natural system that exerts a 100 atm relative pressure can be better defined by referring to the hydrostatic pressure that builds up 1000 metres below sea level .
It is therefore a further teaching of the present invention that of making the best use of the hydrostatic pressure that builds up on one side of a semipermeable membrane at ocean depths ranging between 250 and 1000 metres, whereas on its other side atmospheric pressure is kept, with the aim at exploiting the pressure gap corresponding to the entire hydrostatic pressure that builds up at the depth of interest . To accomplish the above aim there are found to be provided means apt at delimiting a certain volume wherein pressure is kept at atmospheric levels, on the other side of the membrane with respect to that which is subject to hydrostatic pressure. Further aspects, features and advantages of the present invention will be clear from the appraisal of the detailed description that follows, with reference to the appended table of drawings that show a preferred embodiment by way of a not limiting example. In the drawings:
Fig. 1 is a schematic view of a pilot plant for the production and distribution of drinkable water, transformed from ocean water, where underwater chambers are statically hanging from floating islands; Fig. 2 shows in particular an underwater chamber with semipermeable membranes.
Fig.3 is a cross section view of a membrane. With reference to the above drawings, a series of suspended and self-supporting chambers 2 at a 1000 metre depth is fixed.
Each chamber 2 is provided with three communicating openings 4, 6 and 8.
The first of said openings 4 is connected with a vertical chimney 10 which suitably desurfaces from the ocean and is apt to transfer atmospheric pressure into the volume of the underwater chamber which is located at a 1000 m depth.
The second opening 6 is stoppered by semi-permeable membrane blocks 12 which have an outer face E that is subject to a 100 atmosphere pressure, and an inner face I which is only subject to the atmospheric pressure transferred by chimney 10, and a slight depression is further created on it in order to compensate for the weight cf the one Km long air column that overlies it. In such a way there is found to be created the 100 atm pressure gap with the osmotic and inverse osmotic pressure values that results to be necessary in order to get water from the ocean to be filtered without any solutes and/or drinkable water. The third opening 8 is connected with a vertical conduit 14 that itself reaches the ocean surface and is provided with pumps that draw the drinking water which has been filtered into the chamber located underwater from the second opening 6, in such a way as to keep the water level constant inside the underwater chamber. The water surface inside the chamber has in fact to result to be below the lower edge of the membrane, and it is net meant to ever rise to a level that is higher than said lower level of the membrane. According to a preferred embodiment of the present invention, at the zenith of the above described underwater chamber 2 system at a 1000 metre depth and at least 500 metre altitude above the ocean floor, therefore beyond the continental platform, there is found to float a system of buoys 15 which are suitably structured, sized and joined to each other, and carrying a platform or surface 16 mainly covered with photovoltaic cells, whose amount is proportional to the power necessary for the transport of the drinking water produced to the area where it is bound to be used. Said area is horizontally far from the floating buoys 15 at the zenith of the underwater plant which is suspended in the ocean water. Distances along the sea horizon may be in the kilometre range, between 20 and 30 or even less according to the specific underwater morphology.
In order to avoid that a series of horizontally located series of aqueducts running from the ocean to the coast interferes and hinders any type of navigation, the drinking water pipes are located underwater and they are suspended above the continental platform; they are further allowed to crop up and desurface in safe areas that are very close to the coasts. From the coasts and down to the areas where the water is used, drinking water is distributed along underground pipes that may be even much longer than the distance separating the buoys from the coast.
Analysis of the results obtained with tne invention Ocean pressure was simulated. The results obtained in the laboratory lead to the following equation
Q = K S (P-p) where:
K is a coefficient characterising the semipermeable membrane; S is the membrane surface expressed in square metres; p is the osmotic pressure that builds up from ocean water;
P is the hydrostatic pressure of ocean water;
Q is the Kg/s drinking water flow rate and it refers to the drinking water produced. Acting on the size of the surface, and estimating the pressure gap in the order of 75 Kg per square metre, the flow rate results to be:
Q= 75KS Supposing that the permeability coefficient K equals one seventyfifth, which is not true because it is greater, it can be verified that Q equals the S value :
Q = S As the surface S found underwater and expressed as square metres yields to the same flow rate value expressed as Kg/sec that can be easily thought of as litres/s, it appears to be evident that the drinking water flow rate is unlimited even under the most exaggerately unfavourable conditions, as oceans have got depths that are incomparably immense.
From what stated so far there results to be evident how the present invention makes it possible to reduce the overall desalted water production costs. Drinking water production has an investment and production cost per cubic metre of drinking water obtained. Said cost depends on the industrial process which is resorted to and it is proportional to the costs which are related to the power needed. According to the present invention there is found to be a drop in the costs related to the power that is necessary for the production of drinking water at ocean depths as there is no exploitment of temperature, rather of hydrostatic pressure which is naturally available at those depths. The drop in the costs for the production of a cubic metre of drinking water makes it possible to produce large amounts of drinking water at very reduced costs, and it further paves the way to the fight agains desertification.
There is found to further arise a cost related to drinking water transport from ocean waters to the areas where it is bound to be used. The transport from the depths to the surface and from the surface to overground cultivations requires energy.
The energy that is necessary for pumping is electric power. However, the cost of the electric power necessary for the distribution of the product is made to drop, as it was already stated, resorting to photovoltaic energy.
The cost of photovoltaic energy can be categorised into the investment cost for the solar cells and the cost related to power production.
The latter production cost per Kilowatt/hour is negligible, whereas the investment cost for a photovoltaic plant is proportional to the surface available for covering with photovoltaic cells.
The cost of a covered surface in large volumes of ocean water reduces to the mere surface occupation cost; said surface being a wealth that actually belongs to nobody, or juridically speaking it being a "res nullius" it does not weigh on the investment cost for the solar plant.
At the end of the day it results to be evident how the present invention basically takes down drinking water production and transport costs to nil. There are just the investment costs left, the expenses thereto related having to be sustained just once; furthermore they do not increase as the plant operating time increases. This makes it possible to create a situation wherein the costs are paid off very rapidly, the more rapidly, the greater the amount of drinking water produced and distributed is.

Claims

CLAIMS 1. Method for carrying out the extraction of fresh water from salt water, making use of semipermeable membranes, characterised by the fact that according to it, water at over 250 metre depths within natural water basins is desalted, by exploiting the positive gradient existing between the ocean hydrostatic pressure and salt water hydrostatic pressure on an interface which consists of a semipermeable membrane located at the depth of which above.
2. Method according to the preceding claim, characterised by the fact that atmospheric pressure is taken down to depths below sea level on the side of said semipermeable membrane which is opposite to the side onto which salt water exerts its ocean hydrostatic pressure; the fresh water from filtration being pumped to the surface of the ocean.
3. Method according to the preceding claims, characterised by the fact that the fresh water level is kept constant inside the underwater chamber.
4. Method according to the preceding claims, characterised by the fact that it provides for the production of fresh water from salt water without producing any salt or brine waste.
5. Method according to the preceding claims, characterised by the fact that water is desalted by plants which are fully underwater.
6. Method according to the preceding claims, characterised by the fact that it can be carried out thanks to a plant which is totally underwater; the plant being further statically hanging from a floating island and being suspended above the ocean floor.
7. Method according to the preceding claims, characterised by the fact that fresh water wells are comprised, which make up a new type of wells that are full of water bound to any type of use, as they emerge from the ocean surface.
8. Desalting plant of the type wherein salt water is filtered through semipermeable membranes, characterised by the fact that it consists of at least an airtight chamber (2) which is located at an over 250 metre depth, said chamber (2) communicating with the outside through three openings, the first (9) of which is connected to a chimney (10) that suitably emerges from the ocean and that transfers atmospheric pressure into the chamber located underwater; the second opening (6) being stoppered by semipermeable membrane blocks (12) that have an outside face (E) subject to hydrostatic pressure at that specific depth, and an inside face (I) which is subject to the atmospheric pressure taken down along the chimney (10), the third opening (8) being connected with a conduit (14) which suitably reaches the ocean surface itself and down which the drinking water that was previously filtered into the chamber located underneath is drawn through the second opening (6) in such a way as to keep the water level constant inside the chamber located underwater, and not to let it ever overcome the lower edge of the membrane.
9. Plant for the desalting of salt water according to claim 8, characterised by the fact that it further comprises pumps to create a depression m said chimney (10) in order to compensate for the weight of the long air column that overlies it.
10. Plant for the desalting of salt water according to claims 8 and 9, characterised by the fact that said chambers (2) are kept suspended by buoys (15) and or by floating means connected to each other and structured in such a way as to bear a surface and/or platform (16) onto which photovoltaic cells are fixed, in such a way that they can produce the electric power that results to be necessary to carry out the transfer of drinking water to the area where it is meant to be used, said transfer being through conduit (14).
PCT/IT1998/000210 1997-07-29 1998-07-27 Method and plant for desalting seawater exploiting hydrostatic pressure WO1999006323A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU86453/98A AU8645398A (en) 1997-07-29 1998-07-27 Method and plant for desalting seawater exploiting hydrostatic pressur

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ITRM97A000473 1997-07-29
IT97RM000473A IT1296306B1 (en) 1997-07-29 1997-07-29 METHOD FOR THE DESALINATION OF SEA WATER USING THE OWN HYDROSTATIC PRESSURE OF DEEP WATERS AND RELATED PLANT

Publications (1)

Publication Number Publication Date
WO1999006323A1 true WO1999006323A1 (en) 1999-02-11

Family

ID=11405202

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IT1998/000210 WO1999006323A1 (en) 1997-07-29 1998-07-27 Method and plant for desalting seawater exploiting hydrostatic pressure

Country Status (3)

Country Link
AU (1) AU8645398A (en)
IT (1) IT1296306B1 (en)
WO (1) WO1999006323A1 (en)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0968755A3 (en) * 1998-05-25 2000-09-20 Wip Kg Hydrostatic pressure plant for separation/concentration/desalination of liquids, in particular sea or brackish water, via reverse osmosis
EP1164109A1 (en) * 2000-06-14 2001-12-19 Rochem Ultrafiltrations Systeme Gesellschaft für Abwasserreinigung mbH Apparatus for production of potable water
FR2812219A1 (en) * 2000-07-26 2002-02-01 Suido Kiko Kaishya Ltd "WATER TREATMENT DEVICE COMPRISING A MEMBRANE FILTER ASSEMBLY WITH LARGE SIZE PORTS"
ES2170644A1 (en) * 2000-03-22 2002-08-01 Luis Maria Rios-Aragues Production plant of desalinated water by inverse osmosis includes an underwater system with a filter, valving and a water pump
WO2005105271A1 (en) * 2004-04-30 2005-11-10 Brian Douglas Parkinson Static head reverse osmosis
US7726398B2 (en) 2005-06-16 2010-06-01 Bp Exploration Operating Company Limited Water flooding method
EP2125630A4 (en) * 2007-02-14 2011-10-05 Dxv Water Technologies Llc Depth exposed membrane for water extraction
WO2012131621A3 (en) * 2011-03-31 2013-07-04 Dehlsen Associates, Llc Wave energy and solar energy converter with desalination plant
WO2019172775A1 (en) 2018-03-06 2019-09-12 Stolpestad Tor M A method and system for producing freshwater using a reverse osmosis membrane system
US10513446B2 (en) 2014-10-10 2019-12-24 EcoDesal, LLC Depth exposed membrane for water extraction
DE102023132887A1 (en) * 2023-11-24 2025-05-28 Membran Tech GmbH Method and device for desalination of seawater by reverse osmosis

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3171808A (en) * 1960-11-30 1965-03-02 Harry W Todd Apparatus for extracting fresh water from ocean salt water
FR1462017A (en) * 1964-12-30 1966-12-09 Siemens Ag Method and device for the treatment and shaping of substances and workpieces by the action of the natural pressure of water
GB1141138A (en) * 1967-07-19 1969-01-29 Arthur Paul Pedrick Desalination of sea water, using reverse osmosis, in vessels submerged at depths for sufficient hydrostatic pressure
JPS5570387A (en) * 1978-11-22 1980-05-27 Yoshiro Hosoyama Fresh water obtaining system by reverse osmosis
JPS5599379A (en) * 1979-01-24 1980-07-29 Riichi Fujii Deep sea reverse osmotic pressure water making method
JPS55155788A (en) * 1979-05-22 1980-12-04 Nitto Kako Kk Method and device of salt-to-fresh water conversion by reverse osmosis method
JPS5653788A (en) * 1979-10-05 1981-05-13 Isamu Watanabe Fresh water making method from sea water
JPH02187189A (en) * 1989-01-13 1990-07-23 Shiroguchi Kenkyusho:Kk Submerged filter apparatus
US5366635A (en) * 1992-11-27 1994-11-22 Global Water Technologies, Inc. Desalinization system and process
DE19647358A1 (en) * 1996-11-16 1998-05-20 Walter Graef Deep sea water reverse osmosis desalination plant has outer membrane
JPH10156356A (en) * 1996-11-29 1998-06-16 Tokai Univ Desalination method and desalination apparatus

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3171808A (en) * 1960-11-30 1965-03-02 Harry W Todd Apparatus for extracting fresh water from ocean salt water
FR1462017A (en) * 1964-12-30 1966-12-09 Siemens Ag Method and device for the treatment and shaping of substances and workpieces by the action of the natural pressure of water
GB1141138A (en) * 1967-07-19 1969-01-29 Arthur Paul Pedrick Desalination of sea water, using reverse osmosis, in vessels submerged at depths for sufficient hydrostatic pressure
JPS5570387A (en) * 1978-11-22 1980-05-27 Yoshiro Hosoyama Fresh water obtaining system by reverse osmosis
JPS5599379A (en) * 1979-01-24 1980-07-29 Riichi Fujii Deep sea reverse osmotic pressure water making method
JPS55155788A (en) * 1979-05-22 1980-12-04 Nitto Kako Kk Method and device of salt-to-fresh water conversion by reverse osmosis method
JPS5653788A (en) * 1979-10-05 1981-05-13 Isamu Watanabe Fresh water making method from sea water
JPH02187189A (en) * 1989-01-13 1990-07-23 Shiroguchi Kenkyusho:Kk Submerged filter apparatus
US5366635A (en) * 1992-11-27 1994-11-22 Global Water Technologies, Inc. Desalinization system and process
DE19647358A1 (en) * 1996-11-16 1998-05-20 Walter Graef Deep sea water reverse osmosis desalination plant has outer membrane
JPH10156356A (en) * 1996-11-29 1998-06-16 Tokai Univ Desalination method and desalination apparatus

Non-Patent Citations (9)

* Cited by examiner, † Cited by third party
Title
DATABASE WPI Section Ch Week 9035, Derwent World Patents Index; Class D15, AN 90-265588, XP002084291 *
DATABASE WPI Section Ch Week 9834, Derwent World Patents Index; Class D15, AN 98-391817, XP002087795 *
M. REALI: "Submarine and underground reverse osmosis schemes for energy-efficient seawater desalination", DESALINATION, vol. 109, no. 3, June 1997 (1997-06-01), Amsterdam, NL, pages 269 - 275, XP002084290 *
PATENT ABSTRACTS OF JAPAN vol. 004, no. 113 (C - 021) 13 August 1980 (1980-08-13) *
PATENT ABSTRACTS OF JAPAN vol. 004, no. 155 (C - 029) 29 October 1980 (1980-10-29) *
PATENT ABSTRACTS OF JAPAN vol. 005, no. 031 (C - 045) 25 February 1981 (1981-02-25) *
PATENT ABSTRACTS OF JAPAN vol. 005, no. 114 (C - 064) 23 July 1981 (1981-07-23) *
PATENT ABSTRACTS OF JAPAN vol. 014, no. 459 (C - 0767) 4 October 1990 (1990-10-04) *
PATENT ABSTRACTS OF JAPAN vol. 098, no. 011 30 September 1998 (1998-09-30) *

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0968755A3 (en) * 1998-05-25 2000-09-20 Wip Kg Hydrostatic pressure plant for separation/concentration/desalination of liquids, in particular sea or brackish water, via reverse osmosis
ES2170644A1 (en) * 2000-03-22 2002-08-01 Luis Maria Rios-Aragues Production plant of desalinated water by inverse osmosis includes an underwater system with a filter, valving and a water pump
EP1164109A1 (en) * 2000-06-14 2001-12-19 Rochem Ultrafiltrations Systeme Gesellschaft für Abwasserreinigung mbH Apparatus for production of potable water
FR2812219A1 (en) * 2000-07-26 2002-02-01 Suido Kiko Kaishya Ltd "WATER TREATMENT DEVICE COMPRISING A MEMBRANE FILTER ASSEMBLY WITH LARGE SIZE PORTS"
WO2005105271A1 (en) * 2004-04-30 2005-11-10 Brian Douglas Parkinson Static head reverse osmosis
US7726398B2 (en) 2005-06-16 2010-06-01 Bp Exploration Operating Company Limited Water flooding method
EP2125630A4 (en) * 2007-02-14 2011-10-05 Dxv Water Technologies Llc Depth exposed membrane for water extraction
WO2012131621A3 (en) * 2011-03-31 2013-07-04 Dehlsen Associates, Llc Wave energy and solar energy converter with desalination plant
US10513446B2 (en) 2014-10-10 2019-12-24 EcoDesal, LLC Depth exposed membrane for water extraction
WO2019172775A1 (en) 2018-03-06 2019-09-12 Stolpestad Tor M A method and system for producing freshwater using a reverse osmosis membrane system
US11603323B2 (en) 2018-03-06 2023-03-14 Tor M. STOLPESTAD Method and system for producing fresh water using a reverse osmosis membrane system
DE102023132887A1 (en) * 2023-11-24 2025-05-28 Membran Tech GmbH Method and device for desalination of seawater by reverse osmosis

Also Published As

Publication number Publication date
AU8645398A (en) 1999-02-22
IT1296306B1 (en) 1999-06-25
ITRM970473A1 (en) 1999-01-29

Similar Documents

Publication Publication Date Title
US6800201B2 (en) Seawater pressure-driven desalinization method using a gravity-driven brine return
Wolanski Transport of sediment in mangrove swamps
CN102036730B (en) Efficient filtration process of water in a tank for recreational and ornamental uses, where the filtration is performed over a small volume of water and not over the totality of the water from the tank
US3456802A (en) Desalination by submerged reverse osmosis
CN1890184B (en) Mobile desalination plants and systems, and methods for producing desalinated water
ES2620677T3 (en) Method to treat water used for industrial processes
TW200902452A (en) Depth exposed membrane for water extraction
WO1999006323A1 (en) Method and plant for desalting seawater exploiting hydrostatic pressure
SK73398A3 (en) Water desalination
CN103437573A (en) Structure to a large water body for recreational use with color, transparency and cleanness characteristics similar to swimming pools or tropical seas at low cost
US20060191845A1 (en) Method and system for purifying water
Seenayya Ecological Studies in the Plankton of Certain freshwater Ponds of Hyderabad—India I. Physico-chemical Complexes
AU710973B2 (en) Seawater desalination system - Kish water supply scheme
JP4430914B2 (en) Aquatic ecosystem regeneration method
US4263142A (en) Process and system for purifying water
Nyholm et al. Restoration of Lake Nakskov Indrefjord, Denmark, using algal ponds to remove nutrients from inflowing river water
BRPI1001363A2 (en) seawater desalination system and facilities for that purpose
Coppen Advanced wastewater treatment systems
CN103482758B (en) Cruising type water quality purifier for natural water body
AU2014215969B2 (en) Efficient filtration process of water in a tank for recreational and ornamental uses, where the filtration is performed over a small volume of water and not over the totality of the water from the tank
CN2368833Y (en) Apparatus for desalinating seawater at deep sea and pumping
CN211521726U (en) River course is administered and ecological restoration governing system of water
Holt Aquaculture site selection in the Caribbean: an engineering viewpoint
Garcia-Castello et al. Designing a desalination plant for a tourist city located in the Mediterranean Spanish coast
CN1960797A (en) Static head reverse osmosis

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AL AM AT AU AZ BA BB BG BR BY CA CH CN CU CZ DE DK EE ES FI GB GE GH GM HR HU ID IL IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT UA UG US UZ VN YU ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW SD SZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: KR

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: CA