US3322087A - Barge with liquid level control system - Google Patents

Description

May 30, 1967 A. .1. TUCKER 3,322,087

BARGE WITH LIQUID LEVEL CONTROL SYSTEM Filed April 21, 1966 3 Sheets-Sheet l AuyuJf/ne (I Tue/re,

INVENTOR.

y 1967 A. J. TUCKER 3,322,087

BARGE WITH LIQUID LEVEL CONTROL SYSTEM Filed April 21, 1966 3 Sheets-Sheet. 2

65 4 914: f/n e (I Tackefi v INVENTOR.

BY //4I?R IS nun L44 Km! y 1967 A. J. TUCKER 3,322,087

BARGE WITH LIQUID LEVEL CONTROL SYSTEM Filed April 21, 1966 3 Sheets-Sheet.

65 INVENTOR.

A @114 f/n e z/T Tucker BY 4/?R I5 41w 14R KIN United States Patent 3,322,087 BARGE WITH LIQUID LEVEL CONTROL SYSTEM Augustine John Tucker, 911 S. Post ()ak Laue, Houston, Tex. 77027 Filed Apr. 21, 1966, Ser. No. 544,157 Claims. (Cl. 114-.5)

This invention relates to a barge with a liquid level control system for accumulating and storing a water immiscible liquid having a specific gravity less than water at a substantially constant hull displacement. More specifically, this invention relates to a semi-submersible tank barge with a liquid level control system for accumulating, storing and transporting a water immiscible liquid such as oil from an oflshore location to a shore location. The "barge of this invention is particularly adapted for mooring in the open sea, with the control system functioning to load the oil thereinto with a minimum of attention and care, since it will float at a substantially constant level of submergence, i.e., within predetermined limits.

In the conventional production of oil at oflshore locations, it is customary to have fixed tanks mounted on the production platform which have sufiicient capacity so that when an empty oil barge is brought in by a tug, the barge can be loaded and dispatched to the terminal as quickly as possible. Hence, there is a problem of providing a space for the fixed tanks, as well as the necessity for transferring the oil from the tanks to the barges at the desired times, which times may be limited by Weather or wave action. I

In contrast, the barge of this invention is designed to be moored in position near the points of production for long periods of time, with the oil production being di-' verted directly to the barge as it accumulates, which will be at a relatively slow rate. The barge must be able to withstand wide variations in weather and wave action and to continue to act as an accumulation and storage vessel or barge, even during times of critical weather.

The barge of this invention not only reduces the time and expense required for accumulating and storing the oil, but provides a safer means for handling the oil. The design of the barge is such that, because it is submerged, it receives sea action thereagainst almost entirely from the intensity and direction of the current flow. The barge is so configured that it can take the current action on either end without yawing. It is also adapted for mooring in such a fixed position that the loading connections will be held close to a fixed point.

Prior art hulls have been designed to float at deep submergence. However, in almost every instance they a e either manned stations such as a floating drill rig platform, or they are unmanned stations, like weather buoys which have no variation in on-board weight. In neither instance is wind loading avoided, nor are they designed specifically to have their moorings laying entirely to the set and drift of the current.

It is therefore, an object of this invention to provide an improved and novel semi-submersible tank barge with liquid level control means, which barge is adapted for mooring in the open sea adjacent to a producing well for the purpose of accumulating, storing and subsequently transporting the oil to a shore terminal, which barge overcomes the foregoing short-comings of the prior art and provides a solution to the problems mentioned above.

Briefly stated, the barge of this invention includes a first tank or cargo tank adapted to be initially filled with water and substantially submerged, and having outlet means near the bottom thereof and inlet means near the top thereof. A second tank or buoyancy tank is attached to and supported above the first tank and is adapted to 3,322,087 Patented May 30, 1967 be initially substantially empty of any liquid. A third tank or reserve tank is attached to at least one of the said first and second tanks and extends above the water line in which the barge is floating for providing the barge with reserve buoyancy to .prevent complete floundering or submergence of the barge.

There is also provided independently floating receiver means which are associated with the first and second tanks for receiving the liquid which is to be stored and accumulated in the barge. Valve and conduit means are provided for interconnecting the receiver means and the first and second tanks for flowing the liquid from the receiver means into the first tank initially to displace water therefrom, and to alternately divert the liquid to the second tank when the first tank rises a predetermined distance relative to the receiver means as said liquid displaces the water from the first tank.

Reference to the drawings will further explain the in-- vention wherein:

FIG. 1 is a perspective view of a barge made according to the present invention, showing it moored in an open sea position adjacent to producing oil wells.

FIG. 2 is a cross-sectional view through the center of the barge shown in FIG. 1 and showing the barge partially loaded or filled with oil.

FIG. 3 is a view similar to FIG. 2 but showing the barge substantially loaded with oil.

FIG. 4 is a fragmentary and enlarged view of the oil receiver of the barge shown in FIGS. 2 and 3.

FIG. 5 is a schematic end elevation view of an alternate embodiment of the invention.

Referring now to FIG. 1, the barge of the present invention is generally shown by the numeral 11 and is provided with a pair of elongated cylindrical cargo tanks 12 which are connected to and supported by elongated dome shaped buoyancy tank 13 which has connected thereto and supported therea'bove, three tubular shaped tanks 14 which provide reserve buoyancy to the barge to prevent complete submergence of the barge and are selected to be of a size sufiicient to support at least the weight of the materials comprising the barge structure. For purposes of convenience, tanks 14 may sometimes be referred to either collectively or individually as a reserve buoyancy tank, and there may be one or more such tanks.

The barge is moored to the set of the current by means of anchors 17 connected to the barge by anchor lines 18 of conventional design. The source of the liquid which is to be stored in the barge 11 is from producing oil wells 20 which are connected to collecting conduits 21 which in turn are connected to flexible hose 22 which leads to the receiver means provided in center tank 14.

With the barge in position as shown in FIG. 1, its principal bulk is submerged well below the surface of the water. The three cylindrical tubes or tanks 14 pierce the wave zone, extending above it enough to provide a reserve buoyancy and to provide an above water level for performing handling operations on the barge. It is to be understood that dome tank 13 also provides buoyancy and is mounted on top of cargo tanks 12 such that the center of buoyancy of the barge is always above the center of gravity of the barge.

With the hull floating in the position shown in FIG. 1 and having the structure shown, the barge receives practically no loading from winds and there is very little wave action against the tanks 14. While there will be some action from deep wave forces against the faired surfaces of the hull, including cargo tanks 12, it is to be understood that in the deep submerged condition shown, any forces against the barge will be almost entirely caused by current flow. Since estuarial tidal currents are usually directly reversible between ebb and flow and since most open sea currents are persistently in one direction, it is possible to anchor the barge in a fixed position relative to said currents whereby wave and current action will be at a very minimum. So positioned, the barge receives any sea action thereagainst almost entirely from the intensity and the direction of current flow and it is so configured and shaped that it can take this loading on either end without yawing. Thus, it can be moored such that its cargo loading connections will be held close to a fixed point. It is possible, of course, to moor it at one end only so that it will be free to orient to variable current flows. The principal adjustment which would be required would be to revise the loading hose connection so that it will accept the full circumferential swing of the universal mooring.

In prior art submersible barges, various means have Q been employed to keep the hull from rising. For example,

water ballast has been used by pumping it into tanks placed above the water line. Alternatively, heavy weights have been suspended from the bottom of the hull so that they will rest on the sea floor while the hull is in a submerged condition, bringing their load into effect as the rising hull picks them off the bottom. However, the for' mer instance requires human attention and expensive addition of facilities. The latter is crude in its adjustment feature and requires an equivalent extra facility cost. The control features of the present invention provides a solution to this problem and will now be explained by reference to FIG. 2. Tan-k 14, which may be open at its upper end, is attached to and supports dome tank 13 at its lower end. Tank 14 and dome tank 13 have passing downwardly therethrough a vertically extending elongated tube 25 forming an open ended column therethrough.

Dome tank 13 is provided with a plurality of partitions or bulkheads 26 which'extend longitudinally thereof. It is to be understood that similar partitions or bulkheads could also be provided transversely thereof. Each of the partitions or bulkheads 26 is provided with valve 27 which can be remotely operated (by means not shown) for evacuating oil therefrom at the terminal location. In addition, the bottom portion of dome tank 13 is provided with outlet valve 28, which is also used for unloading purposes. Tank 13 is also provided with inlet means near the top thereof in the form of fixed conduits 29 which lead upwardly therefrom as shown. 1 Dome tank 13 has attached thereto and supports each of the cargo tanks 12. Each of the cargo tanks 12 has inlet means in the upper portion thereof in the form of openings 30, each of which connects with or communicates with a conduit tube 31 which lead upwardly therefrom, as

shown.

Each of the tanks 12 has outlet means in the lower por 'tion thereof in the form of outlet conduits 33 which lead to the column inside of tube 25. Each of the conduits 33 is controlled by valve means which includes a valve 34 which may be remotely operated (by means not shown).

Tube 25 has mounted therein for independent floating therein cylindrical float 38 which is adapted to float in r the column of water or a liquid standing in tube 25. Float 38 has connected thereto and supports thereabove receiver means for receiving oil from flexible hose 22, which receiver means includes elbow joint 41 which is connected to deposit oil into cylindrical container 42, the bottom end of which is connected to a vertically extending shank 43 which fits inside of and is adapted for telescopic movement with respect to tubular member 44, the lower end of which is connected, as by welding, to float 38.

Tubular member 44 has a plurality of vertically spaced pairs of holes 47 which are adapted for passage therethrough of bolt 48 which similarly passes through shank 43. Thus, the height at which container 42 is supported relative to float 38 can be adjusted by removing bolt '48 from one of the pairs of holes 47 and repositioning means in the form of a pair of lower openings 50 and portions of cargo tanks 12. Conduits 54 are provided with sufficient slack so that there may be relative vertical movement between container 42 and conduits 31. 1 a

Similarly, upper openings 51 connect with flexible conduits 55, the lower ends of which connect with the upper ends of fixed conduits 29. Again, conduits 55 are provided with slack so as to provide for relative vertical movement between container 42 and conduits 29.

Referring now to FIG. 4, container 42 alsohas floating therein float valve 58 which is slightlysmaller in diameter than the inside diameter of container 42.' Valve 58 is provided with a central valve plug 59 which is adapted to close with the lower end of elbow joint 41 and thereby shut off the flow of liquid or oil therethrough. Valve 58 also has passing therethrough a plurality of vertically extending openings 60 which permit the flow of oil there-v through when plug 59 is not in a closed position, as shown in FIG. 4. Valve 58 will be forced or lifted to the closed position only when the liquid level in container 42 rises Referring now to FIG. 2, float 38 has attached to the lower end thereof, as by welding, valve means which includes valve rod 62 which depends downwardly therefrom. Rod 62 has attached to the lower end thereof a cylindrical sleeve member'63 having horizontally extending valve ports 64 which are adapted to mate with the open ends of conduits 33 when in the position shown in FIG. 2. In addition, sleeve 63 is provided with generally vertically extending openings 65 which provide communication to the column inside of tube 25.

Rod 62 also has supported near the lowerend thereof centering guide means in the form of spider 66"which is adapted for relative vertical movement up and down in- 'side of tube 25 coincidentally-with the movement of rod 62 and float 38. V

In operation of the barge shown in FIGS. 1, 2 and 3, it will be initially placed in the position shown inFIG. 1, i.e., it will be partially submerged with only tanks 14 ex- .tending above the water surface. Cargo tanks 12 will be substantially filled with water if not completely filled with water and dome tank 13 will be substantially'empt-y of oil is flowed through. flexible hose 22 to elbow joint 41,.

which provides'the inlet means to container 42.

The principle whereby the oiliis then flowed to cargo tanks 12 is based on U-tube balance; Depending upon the specific gravity of the oil or liquid'bein-g collected or to be collected in tanks 12, container 42 is adjusted or set the desired distance above float 38 by adjustment of bolt 38 with respect to pairs of holes 47, such that the oil collected in container 42 will automatically-flow into and displace water from tanks 12,'as willnow be explained.

When oil collects in container 42 and rises to liquid level 68 the oil will flow out of lower openings 50 into'flexible conduits 54, to conduit tubes 31 and into the upper .portions of tanks 12. As oil is flowed into the upper portions of tanks 12,.water is displaced from the lower portions thereof and out conduits 33 throuigh valve ports 64. This displacement of water. in the manner described occurs because of the'U-tube principle. In other words, the weight of the column of oil and water in conduits 54 and 31 and to the bottom of tanks 12 is suflicient to overcomej the head pressure of the water column at the bottom of tanks 12. Hence, water is displaced from tanks 12 by what may be described as gravity flow, based on the U-tube principle.

As oil continues to accumulate in tanks 12 by the aforesaid gravity flow based on U-tube principle, tanks 12 will thereby gain buoyancy or become lighter to the extent that theoil has a lower specific gravity than the water which is being displaced. As this occurs, tanks 12 will tend to rise vertically relative to float 38. As this occurs, the barge will assume the position shown in FIG. 3. As tanks 12 rise relative to float 38, sleeve member 63 and hence valve ports 64 are caused to move downwardly relative to the open ends of conduits 33 such that outflow through conduits 33 is stopped. This results in the accumulation of oil in container 42. As oil accumulates in container 42, it rises to the point that oil flows out openings 51 through flexible conduits 55 to conduits 29 and thence to the upper portion of dome tank 13. Bulkheads 26 in tank 13 insure that oil first accumulates near the center thereof to prevent tipping of tank 13. As oil accumulates behind each of the bulkheads 26, and fills up the space therebehind, it then spills over to an adjacent spacing provided by an adjacent bulkhead 26 such that dome tank 13 is loaded from a center point outwardly, thereby insuring stability of dome tank 13.

As the oil accumulates in tanks 12, the on-board weight changes since the heavier sea water has been replaced with lighter oil. The hull adapts to this weight change by risinthis being the only way that it can reduce its total displacement volume of the water. By having the oil-water leg floating, which is accomplished by float 38 which supports container 42, the dimension of the oil and water leg of the U-tube will be fixed, while the water leg of the U-tube changes when tanks 12 move up and down.

With the control feature, i.e., the oil-water leg, at constant dimension, then the motion of the barge upward can be used to switch the loading of the oil from tanks 12 to tank 13.

The cause for the rising of the barge, including tanks 12, may be defined as caused by diminishing displacement due to reduced total weight, Another interpretation would be that the barge has become over-buoyant. The switch of the oil loading from cargo tanks 12 to buoyancy tank 13 may be described as a cancellation of the over-buoyancy. Since tank 13 is initially substantially empty of any liquid, it is ready to accept or accumulate oil therein.

As oil is accumulated in tank 13, the buoyancy thereof is reduced to the extent that oil is accumulated therein. This accumulation causes the barge to sink downwardly relative to float 38 because of loss of buoyancy. As tanks 12, 13 and 14 move downwardly relative to float 38, valve ports 64 become once again aligned with the open ends of conduits 33 such that outflow from tanks 12 can start again. When tanks 12 have taken on suflicient oil to cause the barge to rise again as described above, the cycle can be repeated. Hence, it may be stated that the conduit and valve means are arranged such that oil is alternately diverted from tank 12 to tank 13 until the loading is completed.

When tanks 12 and 13 become fully loaded with oil, then oil will accumulate in container 42 and rise above upper openings 51 so that eventually valve plug 59 will close off inflow of oil to container 42 as shown in FIG. 4. It is important that container 42 be supported a suflicient distance above float 38 such that the weight of the oilwater column of the U-tube will not be so great as to cause underflow or outflow of oil through conduits 33.

In conduit 54, an oil level will exist so that the combined oil-water weight on the tank side will overcome water head on outflow side. Eventually, when all water is purged through conduit 33 to sea, the oil only column in tank 12 andconduit 54 will stand at a point ready to exit out conduits 33, provided container 42 is adjusted to proper height for the three variables-the specific gravity of the immersion fluid, the specific gravity of the oil, the depth of water to the bottom of tank 12.

When oil is loaded onto the barge by introduction into the top of container 42, it will flow into conduit 54. At the start of loading, when the water level in tanks 12 and conduits 54 is the same as the exterior water level, the addition of the oil on top will cause an unbalance in the U-tube and water will flow out through conduits 33, valves 34 and ports 64. As the oil level extends downward in tank 12, the oil level in conduits 54 will also be rising, so that the weight of the combined oil-water column will always be greater than the weight of the column of only water on the outside. The level of oil at the height of openings 51 in container 42 must be set so that when tanks 12 are completely filled with oil to the level of conduits 33, the height of the column up to the level of openings 51 will be equal in weight to the weight of the column of water exterior to the tank. Thus, there are three variables to be met in the adjustment, i.e., the specific gravity of the oil being loaded, the specific gravity of the water in which the tank is floating, and the depth the outflow point below the water line.

Hence, the adjustment feature of bolt 38 relative to shank 43 and tube 44 is provided so that precise balance and control will exist in the termination phase of the loading of the tanks.

In order to determine the precise distance which container 42 must be supported above the water line, it is necessary to determine the required height of the oilwater leg in order to displace water from tanks 12. The formula by which this can be computed is as follows:

Specific gravity of the water of hull This calculation will give the exact height of the oilwater leg. To get the setting of the adjustment above the Waterline on float 38, subtract the designed draft of tanks 12. In addition to adjusting bolt 48, weights may be supported on float 38 in container 42 such that container 42 is supported at the desired height to accomplish the correct weight in the oil-water leg as described above. 7 Since container 42 will contain a variable amount of oil during the operation of the barge, the specific height at which container 42 must be set must take into consideration the dynamic conditions that will prevail. There will be a quantity of oil in container 42, the weight of which will vary as the level therein rises and falls during the loading operation. Hence, a final setting of the height of receiver 42 is selected to take into account these dynamic conditions. As noted above, this final setting can be made by adjusting the height of container 42 relative to float 38 and/or by adding weights to or removing weights from float 38.

When the barge is loaded, i.e., when tanks 12 are filled, and/ or when tank 13 is filled, if this should occur prior to the filling of tanks 12, then the barge can be disconnected from flexible hose 22 and towed directly to the terminal without the need to transfer to another tank barge, thereby eliminating one handling operation entirely. During the movement of the barge of this invention to the terminal or unloading point, there are also many advantages of this barge over other 'barges. It can be towed in a submerged condition. Since it is riding generally below the wave zone, the barge will not incur impaction from the waves, which ordinarily reduces speed. At the unloading terminal, the dome tank 13 would be unloaded first as by opening valve 28 and pumping the oil therefrom. Thereafter, tanks 12 can be unloaded either by closing off valves 34 and then pumping the oil therefrom in a conventional manner. Alternately, cargo tanks 12 can 'be unloaded by ingesting water thereinto. This will create a positive pressure on the suction side of the cargo pumps, assisting in the efiiciency of pumping.

There are many other advantages of this barge and liquid control system. For example, in a conventional barge, when all of the valves to all of the tanks are open and loading commences, there will be a low end or a low specific gravities,

' proportional for a series could be attached to float '38 or placed on receiver 42.

side. Because the piping is sloped in the direction of the low point, that tank will gradually move ahead of its companion tanks and accumulate oil faster. This tends to exaggerate the trim condition. If human supervision :is not present to operate valves to bring the tanks up evenly, the low point tanks will overflow before the high point tanks reach full capacity.

By contrast, with the water displacement system of this invention, the opposite eflect is found to be the case. If a low tank is receiving oil at a faster rate than the others, it will become lighter instead of heavier. Thus, there is a built-in tendency to restore the slope of the piping back to the horizontal position and there-by remedy the cause of the extra flow into the one tank.

Another advantage of the instant invention is that by having the oil flow to dome tank 13 to be initially to the central part thereof, dome tank 13 will be loaded uniformly. Hence, bulkheads 26 in dome tank 13 prevent the creation of a low side during loading thereof.

These two features of trim control permit this barge to be loaded without human attention.

Another advantage of the embodiment shown in FIGS. 1, 2 and 3, is that the oil-water leg of the U-tube principle, i.e., float 38 and container 42, are enclosed within 7 tube 25. Hence, the control system is shielded from the turbulence of the wave zone. Float 38 is not free from rise and fall caused by wave passage on the outside of the barge; the changes in hydrostatic head will be reflected in surges within the'column. However, all of the elements in this system are also enclosed in the column, i.e., both the oil-water leg of the U-tube, and the outflow openings in tanks 12. Hence, operating conditions will remain substantially uneffected by wave action. When float 38 rises on top of a surge, the cause of the rise also causes a counterbalance in the U-tube or the water-leg of the U-tube.

.There is also a built-in safety factor in the design shown in FIGS. 1, 2 and 3, in that the outflow from conduits 33 is to the column inside of tube 25. If it should occur that oil should escape from tanks 12 out conduits 33, the oil will rise to the top of the water in the column inside tube 25. As the oil in the column inside tube 25 accumulates, float 38 will adjust its displacement to suit the lighter medium in which it is then floating. Float 38 will thereafter sink deeper and eventually close the outlets from conduits 33. This will prevent the oil from migrating outward to the sea, thus preventing contamination and financial loss. a

To assure that precise control can be maintained across the full range of different kinds of oils having ditfer'ent 'the dimensions of the barge and its various elements and control system can be designed for a heavyweight oil, as for example, 20 API. By establishing such a base point for the receiver design capacity, standard float and valve dimensions would follow accordingly. For oils of less specific gravity, lead weights of different specific gravities Referring now to FIG. 5, another embodiment of a barge incorporating the invention is shown. As explained a above, FIG. shows a schematic view of a barge having cargo tank 71 with outlet means in the lower part thereof in the form of conduit 72 and inlet means in the upper portion thereof in the form of opening 73. Tank 71 has attached thereto and supports thereabove dome shaped buoyancy tank 75 which also has attached to the upper end thereof a third tank 76 which acts as the reserve buoyancy tank and extends above the water line. Tank 76 is also cylindrical in shape with the top end closed and isadapted for fitting inside of and for vertical relative movement with receiver valve sleeve 78, thereby forming a receiving chamber thereabove, for receiving oil thereinto. Sleeve 78- has lower outlet means which communicates with flexible conduit 79 which connects with inlet 73 of tank 71. Similarly, sleeve 78 has upper outlet means Whichcommunicates with flexible conduit 80 which communicates with the top portion of tank 75.

Tank can be provided with bulkheads similar to bulkheads 26 shown in the embodiments of FIGS. 2 and 3, if desired. Oil is supplied to the inside of sleeve 78 through flexible hose 84 which corresponds with hose 22 in FIG. 1. Hose 84 is connected to a rigid flow line 85 which attaches at one end to sleeve 78 in a fixed relationship and at the other end to a rigid float connector 86 also in a fixed and rigid relationship. Float connector 86 is rigidly connected to float 87 which corresponds with float 38 of the embodiment of the invention shown in FIGS. 2 and 3. However, in this instance float 87 is not isolated from the wave action to the extent that float 38 is, and for that reason the control feature of this embodiment would be less precise. Nevertheless, the operational features are'essentially. the

same as with the embodiment shown in FIGS. 2 and 3,

from in the same manner of operation as with respect to the embodiment shown in FIGS. 2 and 3. In other words, the height at which sleeve 78 rides above the waterline is selected such that the Weight of the oil and water col-' umn of the U-tube principle is suflicient to overcome the weight of the water column of the -U-tube principle. This height of sleeve 78 is determined by its relation-ship to float 87 since it is rigidly connected thereto. Thus, means can be provided (not shown) whereby float connector 86 may be elongated or shortened and/ or additional weight added to or removed from float 87such that sleeve 78 may be supported the desired distan ce'a-bove the water line in the same manner that container 42 was supported above the water line as shown in FIGS. 2 and 3.

As oil accumulates in tank 71 and water is displaced therefrom, the vessel will tend to rise thereby forcing tank 76 upward where it acts as a piston. As tank 76 moves above the lower outlet of sleeve 78, oil willaccumulatev therein until it flows through conduit 'to tank 75. As tank 75 is loaded, the barge will sink to the point that oil once again flows through conduit 79 to tank 71. This alternating flow of oil to tanks71 and 75 will continue until the loading operation is complete in the same manner as with the embodiment shown in FIGS. 2 andg3. In

other words, it may be stated that tank 76 acts as a sleeve valve.

Nevertheless, the control system of FIG. 5 is similar to that shown in the embodiment in FIGSVZ and '3. Rather than controlling the outflow from-tank 71, as does the embodiment of FIGS. 2 and 3, the inflow thereto is controlled by the embodiment shown in FIG. 5.'Nevertheless, the'valving action is still responsive to the vertical movement of tank 71 during the loading thereof. Thus,

it may be stated that both of the embodiments have valve means which are responsive to the vertical movement .of the cargo tank for alternately directing oil between the cargo tank and the buoyancy tank. In both instances, the

. receiver means is mounted to float independently of the cargo tanks and buoyancy tank. In both of the embodiments there are conduit meansfconnecting the receiver means with both the cargo tank and the buoyancy tank.

Similarly, the embodiment shown in FIG. 5 also has the advantage of being substantially submerged and, therefore, removed from wave action. It can be easily moored in the open seal position and moved to a terminal loca-' tion with a minimum of wave action thereon.

Further modifications may be made in'the invention as described without departing from the scope of the invention. Accordingly, the foregoing description is to be construed as illustratively only and is not to .be construed as a'limitation upon the invention as defined in the following claims.

What is claimed is:

1. A barge with a liquid level control for accumulating and storing a water immiscible liquid having a specific gravity less than Water, comprising in combination:

a first tank adapted to be initially filled with water and substantially submerged and having outlet means near the bottom thereof and inlet means near the top thereof;

a second tank attached to and supported above said first tank and adapted to be initially substantially empty of any liquid;

a third tank attached to at least one of said first and second tanks and extending above the water line for providing said barge with reserve buoyancy to prevent complete submergence of said third tank;

independently floating receiver means associated with said first and second tanks for receiving said liquid;

and, conduit means interconnecting said reeciver means and said first and second tanks for flowing said liquid from said receiver means into said first tank initially to displace water therefrom, and to alternately divert said liquid to said second tank when said first tank rises a predetermined distance relative to said receiver means as said liquid displaces said Water from said first tank.

2. The barge as claimed in claim 1 wherein:

said receiver means includes a liquid container mounted to float independently of said first and second tanks;

said conduit means includes a first conduit interconmeeting said container and said first tank and a second conduit interconnecting said container and said second tank;

and, including valve means responsive to the vertical movement of said first tank for alternately directing fluid through said first and second conduits.

3. The barge as claimed in claim 1 wherein:

said receiver means includes a liquid container mounted to float independently of said first tank within predetermined limits above the water level in which the barge is partially submerged and having upper and lower outlets;

said conduit means includes a first conduit interconnecting said lower outlet of said liquid container and said inlet of said first tank and a second conduit interconnecting said upper outlet of said liquid container and said second tank;

and, including valve means responsive to the vertical movement of said first tank with respect to said liquid container for alternately diverting said liquid to said second tank as said first tank rises above a predetermined level as said liquid displaces water therefrom.

4. The barge as claimed in claim 1 wherein:

the center of buoyancy of said barge is above the center of gravity of said barge.

5. The barge as claimed in claim 1 wherein:

the buoyancy capacity of said third tank is suflicient to support at least the weight of materials comprising the structure of the barge.

6. The barge as claimed in claim 1 wherein:

said receiver means is adapted to float above the water line a distance such that the head pressure of the column of liquid inthe conduit means leading from the receiver to the first tank is greater than the head 1O pressure of the water to be displaced from said first tank.

7. The barge as claimed in claim 1 including:

an open ended column member extending vertically through the barge and forming a shaft therethroug-h, the lower end of which is in communication with the water in which the barge is floating;

said receiver means includes float means which are adapted to float in said shaft;

. and, valve means connected to said float means for closing ofl the outlet means of the first tank when said first tank rises a predetermined distance, to thereby divert said liquid to said second tank.

8. A semi-submerged barge having a liquid control system for accumulating and storing oil, comprising in combination:

a cargo tank having inlet means near the top thereof and outlet means near the bottom thereof and adapted to be initially filled with water and sub stantially submerged;

a buoyancy tank having inlet means and connected to and supported above said cargo tank and adapted to at least initially provide buoyancy to said cargo tank;

a reserve tank connected to said buoyancy tank and extending above the water line for providing said barge with reserve buoyancy to prevent complete submergence of said reserve tank;

float means adapted to float independently of said cargo tank;

receiver means connected to and supported by said float means for receiving oil deposited therein; first conduit means interconnecting said receiver means and said inlet of said cage tank; second conduit means interconnecting said receiver and said inlet of said buoyancy tank; and, means for gravity flowing oil from said receiver through said first conduit means to the inlet means of said cargo tank for forcing water therein out said outlet means, and to alternate gravity flow said oil through said second conduit means to said inlet of said buoyancy tank when said cargo tank rises relative to said receiver a predetermined distance as water is displaced from said cargo tank. 9. The barge as claimed in claim 8 wherein: said receiver means includes a container having; inlet means for receiving oil thereinto, upper outlet means connected to said first conduit means for discharging oil therefrom, and lower outlet means connected to said second conduit means for discharging oil therefrom; and, said valve means includes means for flowing said oil out the lower outlet of said container initially and alternately flowing said oil out the upper outlet of said container as said cargo tank rises as oil is collected therein. 10. The barge as claimed in claim 9 including: second valve means adapted for closing off flow of oil to said container when the oil level therein rises a predetermined distance above said upper outlet.

No references cited.

MILTON BUCHLER, Primary Examiner. T. M. BLIX, Assistant Examiner.

Claims (1)

1. A BARGE WITH A LIQUID LEVEL CONTROL FOR ACCUMULATING AND STORING A WATER IMMISCIBLE LIQUID HAVING A SPECIFIC GRAVITY LESS THAN WATER, COMPRISING IN COMBINATION: A FIRST TANK ADAPTED TO BE INITIALLY FILLED WITH WATER AND SUBSTANTIALLY SUBMERGED AND HAVING OUTLET MEANS NEAR THE BOTTOM THEREOF AND INLET MEANS NEAR THE TOP THEREOF; A SECOND TANK ATTACHED TO AND SUPPORTED ABOVE SAID FIRST TANK AND ADAPTED TO BE INITIALLY SUBSTANTIALLY EMPTY OF ANY LIQUID; A THIRD TANK ATTACHED TO AT LEAST ONE OF SAID FIRST AND SECOND TANKS AND EXTENDING ABOVE THE WATER LINE FOR PROVIDING SAID BARGE WITH RESERVE BUOYANCY TO PRE-

Images