EP0050128A1

EP0050128A1 - Bladder device within tanks

Info

Publication number: EP0050128A1
Application number: EP19810900963
Authority: EP
Inventors: Marcel Robert André MOREAU
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-04-14
Filing date: 1981-04-13
Publication date: 1982-04-28
Also published as: FR2480250A1; WO1981003011A1

Abstract

Dispositif de vessie-reservoir souple pour l'equipement interne d'une cuve-citerne a parois rigides pour les stockages et les transports simultanes ou successifs et alternes de plusieurs fluides ou plusieurs produits a caracteristiques fluidiques.Flexible bladder-reservoir device for the internal equipment of a tank with rigid walls for simultaneous or successive and alternate storage and transport of several fluids or several products with fluid characteristics.

Description

EQUIPMENT OF VESSIES-TANKS WITHIN CUVES-CITERNES.

The subject of the present patent application concerns the equipment of bladder-reservoirs inside tank vessels with rigid walls so that they can contain in fixed storage or for transport, either simultaneously or successively and alternatively, different fluids or products with different fluid characteristics, without contact between them, therefore without mixing or salliεsure or any pollution whatsoever between them, and making the best use of the capacities of the volumes of tank vessels thus equipped.

Patents registered in different countries and in particular in France for such devices are already known, but their application is not made, because not very feasible as they are proposed. The process and the devices which are the subject of this patent application make it possible to carry out simultaneous or alternating but strictly separated storage of different fluids or different products with fluid characteristics in a tank tank 1 with rigid walls fitted inside with one or more bladder-type 4 tight-walled bladders using the principles of the natural phenomenon of hydrostatic balance which is better known under the general term of Archimedes principle. The particular problem to be solved is to be able to transport with vehicles of a specific nature another or other products than that for which they were originally designed and built; that is to say: usefully transporting something other than petroleum with a oil tanker, usefully transport anything other than hydrocarbons with barges using so-called "oil" chalans, transport anything other than wine in tankers called "piardardiers" - etc-. For example, an oil tanker on the "return" path may transport fresh water or wheat or corn, or even in the extreme a mixed load according to selected assignments of the bladder-tanks in the different tanks in the boat. Loading and unloading, depending on the fluid characteristics of the products it is intended to transport, can be done according to existing on-board equipment or to be completed on board ships and existing port equipment or to be completed at port docks or out-of-port docking stations ["chiksons"]. This principle, this process and these devices also apply to river, rail or road vehicles. Depending on the absolute separation of the different inlet and outlet mouths, the different conduits, the valves, the pumps required for each of the fluids or products, the filling and emptying operations must be carried out to achieve at all times the balance of hydrostatic character in the whole load of the tank-tank and the bladder-tank in such a way that the separating wall is not subjected to mechanical stresses of expansion of its material which could appear in certain cases according to differences in levels for differences between the filling speeds or the emptying speeds.

In a tank - tank given a year can use several tank-bladders, all in harmony with the basic dimensions, and in this case again the filling and emptying operations must be simultaneous to always achieve the balance of hydrostatic character necessary and mandatory; and this is possible using the technical means already existing, in particular on modern oil tankers equipped with telemetry, remote monitoring and remote control systems of the levels and flow rates of the pumps and valves. Depending on the large dimension in the direction of the depth of certain tank-tanks it is necessary to mechanically support the tank-bladders to avoid their destruction by tears and tears at their upper connection because their flexible material cannot withstand the efforts of traction brought into play by their own weight to which is added the weight of fluids or products remaining adherent to their wall. The bladder-tank equipment devices will therefore include mechanical support means for the latter; the wall will include reinforcements by flexible rings glued and welded in extra thickness to surround in different circles the bladder-tank and on these reinforcements will be anchored suspension cables which will be fixed in high points to the upper part of the rigid tank tank with a length adjustment such that these cables effectively support the weight of the flexible wall and of the adherent products to avoid destructive forces in the material used. If the technical possibilities of manufacturing flexible tank bladders appear temporarily limited, in particular for the equipment necessary for the tanks of super-tanker ships, it is because the need was not felt until now, but according to the general principle that the need and the function create the organ, the large bladder-tanks necessary will be feasible both in the field of component materials and in the required dimensions. All accessories for connections, strainers, piping, valves, pumps, systems for measuring levels, temperatures, and other accessories are of traditional forms and uses and are not part of the inventive idea of present patent filing. Such a process with its devices for use on an industrial scale provides better profitability of the capacities of the volumes of the tank-tanks thus equipped; this equipment provides significant savings in transport energy and better amortization of all other costs inherent in personnel, maintenance and other expenditure; carrying something useful on the way back and which is salable on arrival systematically lowers the cost of these transports. The process and the equipment devices described in this patent contribute to a marked improvement in the general safety of goods and men on board the transport vehicles in question and in particular on board oil tankers by reducing the risk of explosion because the .dangerous gases are practically eliminated due to the filling "again" of the volume of the tanks. Figure [1] simply recalls the fundamental physical phenomenon of hydrostatic balance and the principle of Archimedes.

Figure [2] shows a rigid tank 1 with its internal equipment of a flexible bladder-tank 4 with two fluids A and B.

Figure [3] shows a rigid tank 1 with, for example, internal equipment with four flexible tank bladders 4 shown empty. Figures [4] and [5] show the basic arrangements in the case of a tank tank 1 and a bladder-flexible tank 4 with mouths placed in the upper and lower parts.

Figure [5] schematically shows the ring reinforcement of the flexible wall of a bladder-reservoir 4 with the suspension cables attached to the upper wall of the tank.

In figure [1] the pressures p and p, p 'and p', p "and p" are balanced on each side of the separating wall 4. In figure [23, the rigid tank 1 is equipped with a flexible bladder-reservoir 4 and the fluids A and B are filled and emptied through the mouth openings 2 and 3.

In Figures [4] and [5] the rigid tank vessels 1 are seen in section, one in the case of a parallel-lipedic shape, the other in the case of a cylindrical shape with the orifices of upper filling mouth 2A and 3B and the lower emptying orifices 5A and 5B. In Figure [6], we see the reinforcements 5 of the flexible wall 4, the support cables 7 fixed at points such as 8 of the upper wall 9 of the tank 1. In the explanatory example below, of an oil tanker having to transport successively and alternately crude oil, called crude, and fresh water intended on the one hand for consumption and on the other hand for crop irrigation, the process for using the tank bladder equipment in rigid tanks is as follows:

- in one direction of its route, the tanker has a load of crude and its journey finished it unloads it at its port of arrival;

- the tank washing operations, rinsing and degassing are carried out as usual in the "load on top" system.

- It is then that instead of ballasting and partially ballasting the ship with sea water for good seaworthiness and maneuvering conditions on the return route, tankers 1 are usefully loaded with a certain quantity of any fresh water A, not drinkable, which can be raw river water or water from the sewer of urban origin, which water has the advantage of being charged useful and economical fertilizers for agriculture or arboriculture; then one loads into the bladder-reservoirs 4 fresh drinking water B for human and animal consumption taking the necessary precautions of hydrostatic balance between waters A and B [as explained above] until filling the volume of tanks.

- The ship sets off and thus makes its return voyage in perfect conditions of safety and with a salable and profitable payload;

- at the arrival port, the two water loads A and B are discharged simultaneously, respecting the hydrostatic equilibrium conditions on each side of the flexible wall of the bladder-tanks with the different pumping and storage means put in place for this purpose;

- fresh drinking water B is directly suitable for consumption; non-potable fresh water A is hardly soiled using the "Load on top" process and can be used directly in agriculture or arboriculture for traditional irrigation or by the so-called "drip" irrigation system, because the natural phenomenon of chemotropism in the roots of plants and trees will eliminate the few traces of hydro carbide contained in this water.

As already mentioned above, if this non-potable fresh water comes from urban sewers, it will be loaded with fertilizer products which will largely replace the chemical fertilizers usually used. - The ship refills crude oil in its tanks 1, the bladder-tanks 4 remaining empty, and it resumes its course ... and so on ... for all its systematic and customary journeys back and forth. It is understood that for this oil tanker of our example water seems the most attractive fluid to transport for its ease of handling and according to the enormous needs of fresh water of the countries usually producing oil but economic studies can also lead to use this process for the transport of other goods.

Claims

1. Process for simultaneous, successive and alternating storage but strictly separated from two different fluids A and B or from two different products A and B in bulk, pulverulent or granular, with fluid characteristics, in a tank tank 1 with rigid walls equipped inside with one or more bladders-tight reservoirs 4 with flexible walls, characterized by the use of the principles of the natural phenomenon of hydrostatic equilibrium between the two fluids or fluid products A and B of equal or similar densities on each side of the flexible separating wall 4 the filling and emptying operations of one and the other separate parts of the overall volume with both of the fluids A and B being carried out without the aid of an auxiliary fluid and without application of a pressure or a vacuum of external origin on the walls, the free surfaces of A and B being always at simple natural atmospheric pressure.

2. Device according to the method of claim 1 characterized by the use of a well defined process for the operations of filling and emptying of fluids or fluid products A and B in each of the separate volumes of the tank tank 1 and of the tank-bladder 4 so that there are permanently the conditions for a satisfactory hydrostatic balance on each side of the separating wall 4 and so that this flexible wall thus kept away from the rigid wall 1 does not risk damage by contacts with all the surface defects which may appear there, with the angles and the corners, the internal reinforcements of the construction structures which it comprises for its rigidity and the interior equipment added in certain cases.

3. Method and device according to claims 1 and 2 characterized by the use for several simultaneous or successive and alternate uses of a rigid tank 1 equipped with one or more bladder-flexible tanks 4 mounted on a carrier vehicle maritime, fluvial, land, rail or road which previously had only one specialized use for a specific fluid, with a single payload in one direction of its systematically alternating movements back and forth and which thus acquired the possibility of loading other fluids or fluid products in the other direction.

4. Mechanical support device for the bladder tank 4 in the tank 1 characterized by the application of annular reinforcements B on the flexible wall 4 with anchoring on these cable reinforcements 7 for suspension which are fixed at high points 8 of the upper wall 9 of the tank.