Abstract:
An aquaculture system for allowing live seafood such as clam seeds to grow on a floatation raft which can be positioned in water dock spaces of a marina. A first embodiment allows for an air source such as a regenerative blower to pump air into airlifts under the floatation raft causing seawater to become aerated to flow into and up through screens in container units in the raft allowing for the live seafood on the screens to become both aerated and fed. A second embodiment is a downwell unit where the aerated water flows down the container units through the screens. The upwell air lifts can be modified with spray arm attachments to convert the system from upwell to downwell flow operations. The airlifts can have forty-five degree angled cut bottoms, and include extension tubes for allowing deeper seawater to be introduced into the system. Removable filters can be attached to the airlifts to filter out undesirable contaminants from the system.

Description:
This invention relates to aeration systems for live seafood such as clam seed, and in particular to aeration systems with a floatation box having plural units each having a screened bottom that holds live seafood such as clam seed, fingerling, shell fish, and the like, where seawater is air pumped in either an upwell or a downwell process through the plural units for aerating and washing away waste from the seafood contained in the units. 
    
    
     BACKGROUND AND PRIOR ART 
     Aquaculture systems have been around for many years. Various devices have been proposed for providing aerating systems for all types of fish. See for example, U.S. Patents 463,397 to Walton; 3,196,833 to Glancy; 3,418,973 to Saito; 3,661,119 to Sanders; 3,709,195 to Tabb; 3,795,225 to Ogui; 4,257,351 to Scura et al.; 4,317,429 to Leighton et al.; 4,972,801 to Hunt; 5,092,268 to Taylor; 5,320,068 to Redditt; and 5,762,024 to Meilahn. 
     Glancy &#39;833, Saito &#39;973, Sanders &#39;119, Ogui &#39;225, and Hunt &#39;801 each describe various fish tank systems that are generally landlocked and do not allow for the easy use of seawater for aeration purposes, and thus would not provide a good environment for the culture of live seafood such as clam seeds. 
     Walton, Sr. &#39;397 and Leighton et al. &#39;429 each describe floating panels having screened bottoms but do not describe techniques for aerating any water flow through the screens. 
     Tabb &#39;195 describes a method for hatching and growing marine organisms using an airpumped floatation raft. However, Tabb &#39;195 requires a separate pump 46 to pump in seawater, and does not aerate the water passing into the enclosed raft and does not provide any screened units for supporting separated culture environments for different sizes of seafood, nor for providing either any upwelling nor downwelling water flows into the enclosed raft. 
     Meilan &#39;024 describes an aquaculture system wherein seawater can be pumped along with oxygen into a floating aquaculture container. However, Meilan &#39;024 requires both an electric type water pump 30 and a separate oxygen diffuser 58 FIG. 5, the latter of which requires an “oxygen generator or bottles of liquid oxygen. . . (for) injecting the oxygen into pressurized sea water”, column 5, lines 12-15. Furthermore, Meilan does not describe being able to raise and lower the floating container with the same air supplies, nor does the system describe both upwelling and downwelling water flow aeration of the seafood. 
     Redditt &#39;068 describes an “automatic oxygenation system for aquaculture” where oxygenated seawater can be pumped into the floating container. However, Redditt &#39;068 requires both an electric type water pump 190 and separate aerator 175 FIG.  8 . Furthermore, Redditt &#39;068 does not describe being able to raise and lower the floating container with the same air supplies, nor does the system describe both upwelling and downwelling water flow aeration of the seafood. 
     Both Meilan &#39;024 and Reddit &#39;068 require mechanical operating electrically powered pumps that must operate under a constant load while pumping water. These types of pumps generally require extensive maintenance due to their multiple moving parts such as bearings and seals that can fail and need to be replaced. Furthermore, these types of electric pumps generally require power sources to be located in or close to the water locations causing an inherent potential for electrical shock to both workers and the organisms being cultured. 
     Scura et al. &#39;351 describes a “bivalve production flume”, title, with “upwelling” features for seawater cultivation. However, Scura et al. &#39;351 requires elaborate seafloor trenches and complex distribution system, and does not use any floatation boxes nor airpumps for both the upwelling and downwelling operations. 
     The aeration type systems of the prior art can inherently can create the potential for gas bubble disease by mixing both pressure pumped water and a separate pumped oxygen source. 
     None of the cited patents individually nor in combination describe a system having the capability of using a airpump to aerate seawater in either an upwell or downwell process within a floatation box holding seafood such as clam seeds, where the box is also floated by the same airpump. into a floatation box unit. 
     SUMMARY OF THE INVENTION 
     The first objective of the present invention is to provide an aquaculture system for live seafood having an aeration and air ballast floatation system powered by the same airpump, where the floated box can be raised and lowered for maintenance, and cleaning operations. 
     The second object of this invention is to provide an aquaculture system for live seafood having an air ballast floatation system powered by an airpump which eliminates the need for any lifting machinery, pumps, nor the addition of costly floating docks. 
     The third object of this invention is to provide an aquaculture system for live seafood having an aeration system powered by an airpump where an adapter can be used to allow for both upwelling and downwelling operations. 
     The fourth object of this invention is to provide an aquaculture system for live seafood having an aeration powered airpump with airlift intake that does not rely on mechanical nor separate electric pumps to aerate the water supply. 
     The fifth object of this invention is to provide an aquaculture system for live seafood having an aeration powered airpump with an adjustable length airlift intake for allowing water from different depths to be pumped into the aquaculture system. 
     The sixth object of this invention is to provide an aquaculture system for live seafood having an aeration powered airpump that does not operate under a constant load while the aerated water is flowing into the system. 
     The seventh object of this invention is to provide an aquaculture system for live seafood having an aeration powered airpump that does not require extensive maintenance since the system does not require multiple moving parts such as bearings an seals that can fail and need to be replaced. 
     The eighth object of this invention is to provide an aquaculture system for live seafood having an aeration powered airpump that does not require electric power supplies located in or close to the water locations eliminating the potential for electrical shock to both workers and the organisms being cultured. 
     The ninth object of this invention is to provide an aquaculture system for live seafood having an aeration powered airpump that eliminates the potential for gas bubble disease by using only pumped air to transfer water from the ambient water environment to the culture system. The novel systems use a fiberglass floatation box that contains upwelling and downwelling units that contain different sized screens in which the cultured organisms are housed according to the particular growth stage. Water flow is directed into a flotation box by the pumping system directing the flow of water up or down through the screens and out the drains. In order for the downwelling process to be obtained, an adapter is fitted over the upwelling-pumping head. Water is transferred from the ambient water source via airlifts into the upwelling modules. Aerated water travels up through the screen bottom in the upwelling units and is expelled into the ambient water source through side drains. This process increases the water flow rate and aeration of the surrounding water. Smaller upwelling diameters can be utilized to increase the amount of water flow through the well which fluidizes the clam bed allowing maximized flow rates which invigorates the food source and oxygen supply as well as flushing unwanted feces from the system. 
     Live seafood such as clam seeds can be purchased and placed at a selected density on selected screen sizes in the upwelling units. With the attachment of the downwelling option, clam seed of a much smaller size can be cultivated. Filter attachments and bag filters can be incorporated over downwelling supply tubes filtering ambient water source particles to the downwell. Screens can be fitted over the outlet drains for fin fish culture. The clam seed can be graded and separated by size according to their growth rates and the larger clam seed can be placed on larger mesh screens in separate upwelling units. Clam seeds can be cultivated over several months and grow much quicker using the upwelling and downwelling aerated seawater. 
     The upwell and downwell module boxes use a self sustaining floatation system that eliminates separate floating docks to secure the units. By removing a large drain plug on the end of the upwelling and downwelling module, the water is evacuated by operating the module ballast tanks by air pressure. The ballast tanks can be used to float the module from a semi-submersed position to a full floating position. With full floatation, maintenance such as washing down the outside of the module and/or making repairs can be accomplished. The module can then be submersed to the operating position by releasing the air from the module ballast tanks. Airlists can then be reactivated and operation of the upwelling or downwelling of the system can 5 continue. 
     Further objects and advantages of this invention will be apparent from the following detailed description of a presently preferred embodiment, which is illustrated schematically in the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE FIGURES 
     FIG. 1 shows an exemplary top view of using the novel acquaculture invention in seawater. 
     FIG. 2A is a top view of an upwelling embodiment of the floatation module of FIG.  1 . 
     FIG. 2B is a side cross-sectional view of the upwelling embodiment of FIG. 2A along arrow A. 
     FIG. 2C is an enlarged view of a single upwell unit of FIGS. 2A-2B showing the upwell water flow through the unit. 
     FIG. 2D is a top view of a single screen bottom used in the single upwell unit of FIG.  2 C. 
     FIG. 3A is a top view of the floatation collars and ballast tanks used to raise and lower the floatation module of the preceding figures. 
     FIG. 3B is a side view of the floatation collars and ballast tanks of the floatation module of FIG. 3A along arrow B. 
     FIG. 3C is another side view of the floatation collars and ballast tanks of the floatation module of FIG. 3A along arrow C. 
     FIG. 3D is a bottom view of the flotation collars and ballast tanks of the floatation module of FIG. 3C along arrow D. 
     FIG. 3E is an end view of the floatation collars and ballast tanks of FIGS. 3B and 3C along arrow E. 
     FIG. 4A is a top view of a second embodiment of the upwelling embodiment of FIGS. 2A-2D modified with a spray arm attachment to convert the system to a downwell operation. 
     FIG. 4B is a side view of the second embodiment of FIG. 4A along arrow X. 
     FIG. 4C is an enlarged view of a single downwell unit of FIGS. 4A-4B showing the downwell water flow through the unit. 
     FIG. 4D is a top view of a single screen bottom used in the single downwell unit of FIG.  4 C. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Before explaining the disclosed embodiment of the present invention in detail it is to be understood that the invention is not limited in its application to the details of the particular arrangement shown since the invention is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not of limitation. 
     FIG. 1 shows an exemplary top view of using the novel acquaculture invention 1 in seawater  8 . A floatation module  100  such as an upwelling module  100  shown and described in greater detail in reference to FIGS. 2A-2D. Referring to FIG. 1, an air source 10 such as but not limited to a Regenerative Blower Model No. DR454R58 having 1 .5 HP, 115/230 volt,  1  phase 50/60 Hz Tefc, Class F manufactured by Rotron, is connected by airline  22  to module air pressure line connection  50  (shown in FIG. 3C) to raise and lower module  100  from the seawater  8  for maintenance and cleaning using floatation collars and ballast tanks which are described in detail in reference to FIGS. 3A-3D. 
     FIG. 2A is a top view of an upwelling embodiment of the floatation module  100  of FIG. 1 with  16  cylindrical container units  160  inside support framework  150 , each having external drain pipes  180  of which their use will be explained in relation to FIG.  2 C. Frame work  155  can be a open box having side walls and floor each being approximately ½ inch thick plastic, and the like. FIG. 2B is a side cross-sectional partial cut-away view of the upwelling embodiment  100  of FIG. 2A along arrow A, which more clearly shows the position of the PVC airlifts  120  which pass from beneath the framework bottom  150  to inside and within the framework walls  155 . 
     FIG. 2C is an enlarged view of a single upwell unit  160  of FIGS. 2A-2B showing the upwell water flow through the unit  160  inside the floating framework  150 ,  155  of module  100  which is floating in seawater  8 . Air is pumped through air supply lines  119  from the air control valves shown in more detail in reference to FIGS. 3A-3D, and the regenerative blower air supply source  10  shown in FIG. 1, to the inside of hollow air lift  120  above 45 degree cut open end  122 . The pumped in air  123  causes aerated seawater to be pulled up in the direction of arrow F through hollow vertical airlift  120  to exit at the top open end  124  and overflow into the framework  155  to first surface level S 1 . Unit  160  is elevated above floor  150  which allows the aerated seawater to pass upwell through the bottom screen  170  of unit  160  and about the seafood  175  that is lying over the screen  170 . The aerated seawater both aerates the live seafood  175  and passes out 3 inch drain  180  to the outside seawater  8 . Note that the water height S 1  in the closed framework  155  is higher than the water height S 2  in the individual unit  160  which in turn is higher than the exterior seawater surface height S 3 , thus allowing the water flow F to overflow at F 1  and pass through bottom unit screen  170  as shown by F 2  and out drain at F 3 . 
     FIG. 2D is a top view of a single screen bottom used in the single upwell unit  160  of FIG.  2 C. Each screen  170  can be formed from mesh stainless steel, plastic, combinations thereof, and the like. Unit  160  can each be approximately 12 inches high and have an inner diameter of approximately 18 inches and be formed from PVC, and the like. The subject invention can be used for growing live seafood such as clam seeds and the like. The following Table 1 illustrates the different size clam seeds, the amounts and screen/mesh openings that can be used for cultivation. 
     
       
         
               
               
               
             
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
               
                 Clam Size 
                   
                 Screen opening sizes 
               
               
                 In millimeters 
                 Number of Seeds 
                 in millimeters 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                  1.6 to 4.99 
                 approximately 150,000-250,00 
                 1 
               
               
                 5 to 8 
                 approximately 10,000-150,000 
                 2.5 
               
               
                  9 to 16 
                 up to 10,000 
                 4 
               
               
                   
               
             
          
         
       
     
     FIG. 3A is a top view of the floatation collars and ballast tanks used to raise and lower the floatation module of the preceding figures. FIG. 3B is a side view of the floatation collars and ballast tanks of the floatation module of FIG. 3A along arrow B. FIG. 3C is another side view of the floatation collars and ballast tanks of the floatation module of FIG. 3A along arrow C. FIG. 3D is a bottom view of the flotation collars and ballast tanks of the floatation module of FIG. 3C along arrow D. FIG. 3E is an end view of the floatation collars and ballast tanks of FIGS. 3B and 3C along arrow E. 
     Referring to FIGS. 3A-3E,  110  refers to a ½ inch air control valves,  120  refers to a 6 inch wide PVC air lifts,  130  refers to a ¾ inch PVC air ballast line for port ballast control/valve,  140  refers to a 6 inch Tee, air pressure distribution manifold,  50  refers to a 3 inch air pressure line connection,  135  refers to a ¾ inch PVC air ballast line, port forward control/valve,  34  and  38  refer to submersion/flotation ballast tanks,  37  is port aft tank and  39  is port forward tank,  33  is starboard aft tank and  35  is starboard forward tank,  48  refers to an exhaust/flood ballast tank tubes,  119  refers to an air supply line from air pressure manifold to air lift,  101  refers to a 6 inch PVC drain fitting cap,  111  and  113  refer to a 6 inch PVC air pressure manifold floatation collars,  112  refers to a 1&amp;½ inch PVC to ¾ inch PVC air distribution splitter,  114  refers to air pressure supply valve to control manifold  122 ,  116  refers to welling module tank,  122  refers to air pressure/vent manifold line,  123  refers to air pressure vent valve,  133  refers to a ¾ inch PVC air ballast line with starboard forward ballast control/valve,  134  refers to air supply line/vent line starboard forward ballast/flotation tank,  136  refers to air supply line/vent line port forward ballast/flotation tank, and  137  refers to a ¾ inch PVC, air ballast line and starboard aft ballast control/valve. 
     The raising of the flotation module  100  in FIGS. 3A-3E will now be described in the following ten (10) steps. 
     (1) Remove six inch drain plug  101 . 
     (2) Close valve  123 . 
     (3) Open valve  112 . 
     (4) Open valves  133  and  135 . 
     (5) Flotation tubes/tanks  38 ,  39  and  34 ,  35  fill with air, ballast water is expelled through exhaust/flood ballast tank tubes  48 . 
     (6) Flotation module manifold end (FIG. 3E) rises tilting internal water to drain plug end  101 . 
     (7) Outward flow of water from drain plug  101  ceases. 
     (8) Close valves  135  and  133 . 
     (9) Open valves  130  and  137  to fill aft ballast tubes/tanks  33  and  37  with air. 
     (10) Aft end of tank  33 ,  37  begins to rise to same level as front of tank  35 ,  39  expelling remainder of water in flotation module  100  out drain plug  101 . 
     The lowering of the flotation module  100  in FIGS. 3A-3E will now be described in the following fifteen(15) steps. 
     (1) Air pressure valve  112  is closed. 
     (2) Supply/vent valves  130  and  137  are opened. 
     (3) Valves  133  and  135  are closed. 
     (4) Vent valve  123  is opened. 
     (5) Air expels from valve  123  as water floods aft ballast tubes  33 ,  37  through exhaust/flood ballast tank tubes  48 . 
     (6) Module  100  tilts toward drain plug  101  opening and begins to submerse on aft end while water floods in through drain plug  101 . 
     (7) Air stops venting through valve  123  during complete flooding of aft ballast/flotation tubes/tanks  33 ,  37 . 
     (8) Valves  130 ,  137  and vent valve  123  are left in open positions. 
     (9) Valves  133  and  135  are opened. 
     (10) Air begins venting from vent valve  123  as air expels from front ballast/flotation tanks/tubes  35 ,  39 . 
     (11) Air stops venting from vent valve  123  until there is a complete flooding of ballast flotation tank/tubes  35 ,  39 . 
     (12) Tank  100  has settled into surrounding ambient water until flotation collars 111, 113 sit on the water. 
     (13) Vent valve  123  is then closed. 
     (14) Pressure valve  112  is opened, and valves  130 ,  137 ,  133 , and  135  are selectively opened if the module  100  needs to be leveled and trimmed. 
     (15) Air lift control valves  110  are then opened feeding air through air lift lines  119  to airlifts  120  to begin pumping action air back into welling module tank units  160  in order to proceed with upwelling and downwelling operations. 
     FIG. 4A is a top view of a second embodiment  200  of the upwelling embodiment of FIGS. 2A-2D modified with a spray arm attachment  210  to convert the system to a downwell operation. FIG. 4A shows that both downwell and upwell flow systems can be used simultaneously in the same flotation module. FIG. 4B is a side view of the second embodiment  200  of FIG. 4A along arrow X. FIG. 4C is an enlarged view of a single downwell unit  260  of FIGS. 4A-B showing the downwell water flow through the unit. FIG. 4D is a top view of a single screen bottom  270  used in the single downwell unit  260  of FIG.  4 C. 
     Referring to FIGS. 4A-D, a spray arm mount attachment  210  having a central bottom open end  211  can be fit over the upper opening to airlift  120  by conventional fastening such as internal threads, bolts, and the like. Spray mount attachment  210  can have up to four spray arms  212 ,  214 ,  216 ,  218  that extend outward therefrom having through-holes therethrough. Each well unit  260  is cylindrical to unit  160  previously described, except unit  260  does not have side outlets. Instead separate outlet pipes  280  are only mounted in the sidewalls of frame  155 . Unit  260  has a screened bottom  270  on which live seafood  275  such as clam seed can be supported. Ambient seawater can flow into the bottom 45 degree angled cut opening of airlift  120  in the direction of arrow M and be aerated by airsupply bubbles  123  as described in the previous embodiment. The attachment mount  210  directs the aerated seawater to through each of the arms  212 ,  214 ,  216 ,  218  and into the upper open end ofeach unit  260  as shown by arrow M 1 . The aerated seawater flows downwell though the live seafood  275  through screen  270  in the direction of arrow M 2  up the side of the frame  155  to exit out side exit port  280  into the ambient sea  8 . Note the water level t 1  inside of frame  155  is lower than the water level t 2  inside each well unit  260 , and the exterior seawater  8  has the lowest water level t 3 . 
     The following Table  2  illustrates the different size clam seeds, the amounts and screen/mesh openings that can be used for cultivation in the downwelling embodiment using well units  260  that are each 12″ deep. 
     
       
         
               
               
               
               
             
           
               
                 TABLE 2 
               
               
                   
               
               
                 Clam Size In 
                   
                 Screen opening 
                 Well Unit 
               
               
                 millimeters 
                 Number of Seeds 
                 sizes in microns 
                 Diameter 
               
               
                   
               
             
             
               
                 Less than 1 
                 approximately 2,000,000 
                 approximately 250 
                 24″ 
               
               
                 1 to 1.1 
                 approximately 1,000,000 
                 approximately 500 
                 24″ 
               
               
                 greater 
                 approximately 250,000 
                 approximately 800 
                 18″ 
               
               
                 than 1.1 
               
               
                   
               
             
          
         
       
     
     Referring to FIG. 4B a separate filter cover  400  can be attached by conventional fasteners  415  such as but not limited to threads, bolts, and the like, to the upper opening of each airlift  120  and include a closed top  405  and a screened bottom  410  which can be used to screen out undesirable contaminants such as debris, and the like from the aerated seawater entering into the system. An optional extension pipe  300  having a forty five degree angled cut bottom  315  can be slipped over the existing bottom end of airlift  120  by threads and the like, in order to allow deeper seawater such as deep coldwater to be brought into the system. 
     While the invention has been described, disclosed, illustrated and shown in various terms of certain embodiments or modifications which it has presumed in practice, the scope of the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved especially as they fall within the breadth and scope of the claims here appended.