Abstract:
A tidal-powered desalinization system is mounted on a barge that oscillates about fixed pier structures, generating a two-way pumping action. The two-way pumping action is changed to a single direction flow of seawater. The sea water is directed into an on-board desalinization system. Fresh water is produced and collected in reservoirs, without an intervening generation of electricity.

Description:
PRIORITY CLAIM 
     This invention claims priority to U.S. provisional application Ser. No. 60/370,085, filed Apr. 4, 2002. 
    
    
     FIELD OF THE INVENTION 
     This invention relates generally to ocean powered desalinization systems. 
     BACKGROUND OF THE INVENTION 
     It has long been recognized that the oceans provide tremendous potential in kinetic energy which can be harvested to generate electricity. Across the globe there are many tidal electric generation systems installed and in full operation. An example of an installed and fully operational tidal electro-generation system is the barrage system installed near St. Malo on the Brittany Coast in France across the La Rance estuary. The St. Malo system is a 240 megawatt system and has been reliably generating electricity for a good number of years. Despite this good record the complete blockage of the La Rance estuary has caused significant environmental effects. The submerged turbine blades have interfered with migration of fish and the overall barrage itself has blocked shipping. Other tidal powered systems include tidal fences and submerged underwater windmills and all have a greater or lesser effect on the environment. The aforementioned power generating systems, though effective, are big and require a complex series of power grids to convey the power off the barrage or tidal fence to an offshore power collection and distribution system. 
     Smaller tidal and wave powered electro-generation systems include various wave riding devices which bob up and down and move dynamos that generate electricity. Although these systems are smaller and can be located at remote locations, they nevertheless require electricity to be harvested and a grid to be constructed onto these bobbing devices. The grid in particular is cumbersome and has limited their practical implementation. 
     Various locations across the globe in which tidal ranges are ideal for generating electricity are places that also happen to be devoid of water. Such locations are in Africa, the Mideast and Polynesia. As these desert coastal regions are commonly devoid of electricity and drinkable water, various devices have been proposed to meet both the electricity and potable water demands of coastal residents. Such a system is described in U.S. Pat. No. 5,167,786 which generates compressed oxygen and hydrogen gas on a toroidal float which moves up and down with the waves and the tide. This up and down motion drives a DC generator which in turn is arranged to electrolytically produce hydrogen and oxygen gas. The hydrogen and oxygen gas is stored on the toroidal float apparatus and transferred to a reaction chamber to chemically generate electricity. Electricity thus generated is then sent to a DC motor to drive a high pressure pump which forces sea water through a reverse osmosis membrane to remove salt and produce drinkable fresh water. This toroidal gas generation system to generate electricity to drive electric DC motors in order to make drinkable water is a desalinization system which works but it is unnecessarily complex. Where there is a need primarily for fresh water to be generated from a desalinization process especially in remote regions a gas generated gas reactor system is unduly complex and likely to not have the robustness to serve in remote locations. Furthermore, such a system is very costly. 
     In many desolate parts of the world that have a good tidal and wave coastline but yet is primarily in an arid region there is a need to have a robust mechanically simple desalinization system powered by the tides and wave action of the seas. Such a system is simplified if it does not have electric generators but instead goes directly to the desalinization process. Such a simplified system uses the potential and kinetic energy of the oceans to directly send saltwater into a desalinization system without the intervening production of electricity inherent in other systems. 
     The need for a simplified robust desalinization system powered directly by the oceans to make fresh water and store the fresh water is needed. Such a system must be fairly mobile, assembleable, disassembleable, and transportable to remote coastal locations where potable water is not easily obtained. 
     SUMMARY OF THE INVENTION 
     The instant invention overcomes many of the disadvantages of having a dual electricity generation system and a saltwater desalinization system. A preferred embodiment of the present invention utilizes a barge mounted to a plurality of pistons that reciprocate inside a matching plurality of vessels or cylinders, and utilizes the vertical motion being caused by the action of tidal forces and waves. Each piston is in fluid communication with the ocean as the source of power to perform on board desalinization. The barge is restricted to up and down vertical motions via a plurality of posts or piles secured by embedded positioning into the bedrock of the sea floor to stabilize the barge against ocean-caused lateral displacement. The up and down motion of waves and tidal forces causes the pistons to reciprocate upwards and downwards with its waves and tides. That is, as the tide rises or falls, the pistons rise and fall, generating a two-way pumping action. This pumping action is due to the combined forces of rising tides and falling tides, or the combined forces of rising waves and falling waves. There is no intervening electric generation of power from the use of alternate powered devices. This reciprocating pumping action delivers a pressurized saltwater flow. Using a plumbing and valving system, the pressurized saltwater flow is directed to an on board desalinization system, such as a reverse osmosis (RO) filtration system, that generates and stores fresh water into reservoirs by being powered directly from the reciprocating movement of waves and tides. The on board desalinization system is in fluid communication with each cylinder and reservoir. 
     Another preferred embodiment of the present invention does not utilize bedrock embedded piles or posts to keep the barge positioned at a chosen site on the ocean floor, but instead secures the barge&#39;s ocean floor location through supports massive enough to resist lateral displacement caused by wave and tidal action. This alternate preferred embodiment is particularly suited for ocean floors having deep sandy beds. 
     Yet another preferred embodiment of the present invention uses a single pile or post floating barge or platform that slidably oscillates between vertical limits imposed by wave and tidal action. The single pile is secured to the ocean floor by a support massive enough to resist lateral displacement of ocean flows. The pile or post projects through a platform aperture. Alternatively, the single pile may be embedded in the ocean floor to increase stability against lateral displacement. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The preferred and alternative embodiments of the present invention are described in detail below with reference to the following drawings. 
         FIG. 1  is a preferred general arrangement of an approximately 50 foot by 100 foot barge which contains the desalinization system. The cylinders are depicted below the water line, and barge positions depicted include a high tide position and a low tide position; 
         FIG. 2  is an up view or plan view of the preferred deck arrangement of the barge; 
         FIG. 3  is a cutaway view detailing a cutaway view of a preferred reverse osmosis filtration system and storage reservoir arrangement in the approximately 50 foot by 100 foot barge; 
         FIG. 4  is a depiction of the preferred machinery arrangement in a cutaway view of the approximately 50 by 100 foot barge; 
         FIG. 5  is a depiction of a preferred arrangement of the cylinder and in-flowing and out-flowing check valves; 
         FIG. 6  is a schematic of the reverse osmosis purification system and its piping connection with cylinders and storage reservoirs; and 
         FIG. 7  is a schematic depiction of a preferred embodiment of the invention with the cylinders located above the water line. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Arrangement of the barge mounted tidal powered desalinization system comprises a series of pistons mounted to the barge which oscillate within cylinders attached to a shaft which is mounted into the bedrock of the ocean bed. To the shaft are attached a plurality of cylinders where each cylinder has a piston and the piston has a rod which is attached to the barge bottom. As the barge moves up or down with tidal or wave action the pistons move up or down within the cylinders. Through appropriate plumbing valves to direct the flow of saltwater in a one-way direction results in the delivery of saltwater into the reverse osmosis membranes. 
     The design of the instant invention using the rising and falling of the tides to create a flow of seawater under pressure suitable for feeding existing reverse osmosis desalinization systems. The design consists of a floating vessel attached to one end of a standard type hydraulic cylinder, the other end of the cylinder is connected to the sea floor. As the floating vessel or barge rises and falls with the tides, the cylinder is extended and compressed. This motion pumps the seawater. The pressure and flow rate of seawater depends on cylinder size and the mass of the vessel and the displacement of the vessel which occurs during tidal cycles. 
     On the upward stroke of the cycle the buoyant force of the float limits the amount of pressure that can be created. On the downward stroke the weight of the float determines the maximum pressure. The actual work on the down stroke is a function of gravity, not of the tides. The cylinders are sized so that the float is not really floating but is suspended on the cylinders. 
     In concert with the up and down motion of the barge in response to tidal flows and wave action, the cylinders are configured to cyclically deliver pressurized saltwater for subsequent desalinization. Simultaneously, the pressurized and delivered saltwater is replaced with incoming charges of salt water that will be subsequently pressurized and delivered for desalinization with the next tidal or wave action. For example, as the tide recedes the buoyant force on the barge decreases and the barge falls, pushing each piston downward into their respective cylinders. During each piston&#39;s downward stroke, each cylinder is configured to deliver pressurized saltwater for desalinization, and concurrently, to fill each cylinder with a replacement charge of saltwater. Similarly, as the tide comes in, the buoyant force on the barge increases and the rising barge pulls each piston upward into their respective cylinders. During the piston upward stroke, each cylinder is configured to deliver pressurized saltwater for desalinization, and concurrently, to fill each cylinder with a replacement charge of saltwater. 
     Thus, an unbalanced hydraulic cylinder is used as the pumping mechanism. The down stroke acts on the larger surface area of the cylinder. This is done so that the substantial mass of the floating vessel can be used to create pressure and flow. On the upstroke, buoyant forces lift the floating vessel, thereby acting on the smaller surface area portion of the hydraulic cylinder, generating a forward flow of saltwater. As the tide recedes, the floating vessel sinks, generating a down stroke. The down stroke generates a reverse flow of saltwater. The result is a system that is half powered by tidal forces and half powered by gravity. Pumping action can also be used to pump the fresh water exiting the reverse osmosis filters into the water distribution system resulting in the conversion of saltwater into potable water under pressure without any electrical or fuel input. 
     The invention is best described by referring to the figures. In  FIG. 1  the invention  10  is shown in two positions depending upon the tide position. A barge  12  is located in a high tide position and a low tide position. The Barge  12  moves up and down about along a first post  14  and along with a second post  34 . Attached to the top side of the barge  12  is a first platform  15  which circumscribes the first post  14  and a second platform  42  which circumscribes the second post  34 . The first post  14  and the second post  34  are mounted into the bedrock of the ocean floor. The first post  14  is supported by a first post guide  30  and the second post  34  is supported by a second post guide  36 . The first and second guides  30  and  36  sit atop the bedrock of the ocean floor. On the first guide  30  is seen a first plurality of cylinders that includes a first cylinder  20  and a second cylinder  32 . On second guide  36  is seen a second plurality of cylinders that includes a first cylinder  38  and a second cylinder  40 . Within each cylinder is a piston seal and a piston rod assembly. Referring to the first cylinder  20  as representative for other cylinders, the other cylinders including, but not limited by, the second cylinder  32  of the first plurality of cylinders and the second cylinders  39  and  40  of the second plurality of cylinders, the piston rod assembly includes a piston seal  22  which is attached to a piston rod  18 . The piston rod  18  is mounted to the first platform  15  by a rod end  16 . Likewise, other piston rods are attached to the other seals within the other cylinders and are similarly attached to the first platform  15  and the second platform  42 . As can be seen in  FIG. 1  there are two extreme positions to the barge  12  when it floats at high tide and when the barge  12  floats at low tide. Similarly, the pistons will also occupy two extreme locations, the high tide position and the low tide position, and reciprocate within their respective cylinders. As depicted in  FIG. 1 , the piston seal  22  occupies the top position of the first cylinder  20  when the barge  12  is at high tide, then transits down the first cylinder  20  to the low tide position. As the tides and the waves oscillate in their own diurnal cycle, the piston seal  22  migrates between the high tide extreme and the low tide extreme. In so doing, saltwater is pumped by the movement of the barge as a consequence of rising with the tide and falling with gravity, generating a pressurized saltwater flow powered by a suction cycle and a discharge cycle. Using a plumbing and valving system (not shown), the suction and discharge cycles of the double acting cylinders are regulated to produce a steady pressurized flow of saltwater. The plumbing and valving systems include a first plumbing and valving system configured to deliver pressurized water to the on board desalinization system and a second plumbing and valving system configured to deliver incoming saltwater to the cylinders concomitantly as the pressurized saltwater is delivered from the cylinders. 
       FIG. 2  shows in more detail the deck arrangement of the barge  12  in a top view. The top of the barge  12  is shown the first post  14  and the second post  34 . The first post  14  is surrounded by the first platform  15  and the second post  34  is shown surrounded by the second platform  42 . Beneath the first platform  15  is the first plurality of cylinders. The first plurality of cylinders includes the first cylinder  20 , the second cylinder  32 , a third cylinder  60 , and a fourth cylinder  62 . Beneath the second platform  42  resides the second plurality of cylinders. The second plurality of cylinder includes the first cylinder  38 , the second cylinder  40 , a third cylinder  64 , and a fourth cylinder  66 . 
       FIG. 3  shows a cutaway view of a preferred reverse osmosis filtration system and storage reservoir arrangement in the approximately 50 foot by 100 foot barge. The cutaway view is from the top view of the barge  12 . The cutaway view  104  shows four compartments. The four compartments include a first compartment  110 , a second compartment  120 , a third compartment  130  and a fourth compartment  140 . Each compartment contains a stack of reverse osmosis membranes and a plurality of water storage reservoirs. The first compartment  110  shows a first reverse osmosis stack  112  which is fed by a first plurality of pre-filtration tanks. The first plurality of pre-filtration tanks include a first tank  114 , a second tank  116 , and a third tank  118 . The second compartment  120  has a second reverse osmosis stack  122  which is fed by a second plurality of pre-filtration tanks. The second plurality of pre-filtration tanks includes a first tank  124 , a second tank  126 , and a third tank  128 . The third compartment  130  has a third reverse osmosis membrane stack  132  which is fed by a third plurality of pre-filtration tanks. The third plurality of pre-filtration tanks include a first tank  134 , a second tank  136 , and a third tank  138 . The fourth compartment  140  contains a fourth reverse osmosis stack  142  which is fed by a fourth plurality of pre-filtration tanks. The fourth plurality of pre-filtration tanks includes a first tank  144 , a second tank  146 , and a third tank  148 . Each reverse osmosis stack uses a third plumbing and valving system (not shown) to deliver the generated fresh water to the plurality of water storage reservoirs. Also seen in the cutaway view  104  is a first moon pool  150  delineating the space for the first post  14  and a second moon pool  160  delineating the space for the second post  34 . Each reverse osmosis stack can be loaded with RO membranes configured to meet varying levels of salinity and silt contents in the saltwater. 
       FIG. 4  is a side cutaway view of the barge  12 . The first and second platforms  15  and  42  are shown above the first compartment  110  and the second compartment  120  respectively. Within the first compartment  110  is seen the first reverse osmosis stack  112  and the second pre-filtration tanks  116  and  118  of the first plurality of pre-filtration tanks. Similarly, inside the second compartment  120  is seen the second reverse osmosis stack  122  and the first and second pre-filtration tanks  124  and  126  of the second plurality of prefiltration tanks. 
       FIG. 5  is a depiction of a preferred arrangement of the cylinder and in-flowing and out-flowing check valves.  FIG. 5  shows the arrangement for the cylinder  20  but is also representative for cylinders  32 ,  38 , and  40  of FIG.  1 . Inside the cylinder  20  is a connecting rod seal  204  that makes and maintains sealing contact with the connecting rod  18 . As the connecting rod  18  reciprocates within the cylinder  20 , the piston  22  creates a vacuum on the trailing side of the piston  22 , and simultaneously creates pressure on the leading side of the piston  22 . The vacuum created on the trailing side of piston  22  pumps in saltwater through incoming check valves  208 A or  212 A, depending if the piston  22  is moving downwards, or upwards, respectively. Similarly, the pressure created on the leading side of the piston  22  pressurizes the salt water and delivers to the outgoing check valves  208 B and  212 B, depending if the piston  22  is moving upwards or downwards, respectively. 
       FIG. 6  is a schematic of the reverse osmosis purification system its piping connection with cylinders and storage reservoirs. Again, using the cylinder  20  as representative for cylinders  32 ,  38 , and  40  of  FIG. 1 , ambient pressure saltwater is drawn in through incoming check valve  208 A through a first pipe  216 . Alternatively, ambient pressure saltwater is drawn in through incoming check valve  212 A trough a second pipe  220 . Depending on the position of the connecting rod  18  and the piston  22 , pressurized saltwater is delivered to the outgoing check valves  208 B and  212 B. Pressurized saltwater from outgoing check valve  208 B is delivered by a third pipe  224  to a reverse osmosis filtration system  234 . Similarly, pressurized saltwater from outgoing check valve  212 B is delivered by a fourth pipe  228  to the reverse osmosis filtration system  234 . The reverse osmosis filtration system  234  includes the reverse osmosis stacks  112 ,  122 ,  132 , and  142  working in concert to produce purified water from saltwater. Saltwater excess not purified by the RO system  234  is discarded through a fifth pipe  238 . Freshwater generated by the RO system  234  is delivered through a sixth pipe  244  to a plurality of storage reservoirs  248 . The plurality of storage reservoirs  248  is representative of the reservoirs  114 ,  116 ,  118 ,  124 ,  126 ,  128 ,  134 ,  136 ,  138 ,  144 ,  146 , and  148 . 
       FIG. 7  is a schematic depiction of a preferred embodiment of the invention with the cylinders not immersed in the saltwater, but instead located above the water line and located onboard the barge. A portion of the barge  12  illustrating the post  14  is shown in FIG.  7 . The first pipe  216  and the second pipe  220  extend below the water line and each connects with the cylinder  20  that is now located onboard the barge  12 , above the water line. Incoming saltwater is delivered via the first pipe  216  and the second pipe  220 . Pressurized saltwater is delivered to the RO system  234  (not shown) from the cylinder  20  via the third pipe  224  and the fourth pipe  228 . 
     While the preferred embodiment of the invention has been illustrated and described, as noted above, many changes can be made without departing from the spirit and scope of the invention. For example, more than two piles or posts can be used as vertical guides to the barge. More than four piston and cylinder assemblies may be mounted around each pile or post, and may be located in different sections of the barge. The vessels or cylinders may be constructed of metal, corrosion resistant metals, plastics, or plastic-lined metals of sufficient thickness and corrosion resistance to permit pumping action. For the preferred alternate embodiment not utilizing bedrock-embedded piles or posts to stabilize against ocean motion caused lateral displacement of the barge, the pile guides are configured to receive cement or receive heavy object attachments to impart enough weight and mass to resist and stabilize the barge against lateral displacement from ocean motion forces. All embodiments of the present invention may also be used to purify polluted fresh water sources. Piles or posts may be connected to the barge internally through barge apertures or secured along the periphery of the barge with collars. Cylinders may be placed around the piles or internally spaced above or below throughout the cross-sectional area of the barge platform. The invention may be adapted to existing floating structures, such as airport runways and parking lots. Accordingly, the scope of the invention is not limited by the disclosure of the preferred embodiment.