RU2220872C2 - Method and device for replacement of ballast water on board ship - Google Patents

Abstract

FIELD: shipbuilding; devices for replacement of ballast water in shipboard tanks. SUBSTANCE: proposed device for replacement of ballast water in ballast tank 6 of ship 5 has water inlet hole 11 in part of ship where pressure of water acting on ship during her forward motion exceeds pressure of ballast water being replaced, outlet hole 14 made in ballast tank and water inlet passage 12 running between hole 11 and ballast tank 6 for supply of ballast water to tank under pressure exceeding pressure of ballast water in tank. Thus, ballast water is forced out of ballast tank through outlet hole 14 and is replaced with water admitted through inlet hole 11. EFFECT: reduced power requirements; facilitated procedure of water replacement. 5 cl, 7 dwg

Description

 The technical field to which the invention relates.

 The invention relates to a method and apparatus for replacing ballast water in a ballast tank of a vessel, as well as a vessel that uses a ballast water replacement system.

State of the art
A ballast tank is used on the ship to stabilize the ship. To perform this function, the ballast tank is filled with water. Since there is the possibility of contaminated water entering the ballast tank, it is necessary or desirable to replace such contaminated ballast water with clean water.

 Typically, ballast water is replaced using a pump. This requires energy costs, as well as operator involvement to control the process.

 An object of the present invention is to facilitate the replacement of ballast water.

SUMMARY OF THE INVENTION
In accordance with the invention, there is provided a method for replacing ballast water in a ship’s ballast tank, using a water inlet in a part of the ship, where the pressure of the water acting on the ship when it moves forward in the water is greater than the pressure of the ballast water to be replaced; connecting said water inlet with a ballast tank containing ballast water to be replaced, for supplying said water under increased pressure from the inlet to the ballast tank; and using the pressure difference of the pressurized water from said inlet and the ballast water to displace the ballast water from the ballast tank, whereby the ballast water is replaced by water from the inlet.

 Also in accordance with the invention, there is provided a device (system) for replacing ballast water in a ship’s ballast tank, including a water inlet (port) located in a part of the vessel on which the pressure of the water acting on the vessel when it moves forward in the water exceeds the pressure ballast water to be replaced, a water outlet (port) in the ballast tank and a water inlet for supplying water to the ballast tank under a pressure greater than the pressure of the ballast water in the tank, with the crowding out water from the ballast tank through said water outlet, said water inlet being located between said water inlet and said ballast tank.

 It is desirable that the water inlet is located in front of the bow of the vessel, which is normally under water when the vessel moves forward.

 The invention also relates to a vessel having the ballast water exchange device described above.

 Other objects and advantages of the invention will be apparent from the following description of preferred embodiments of the invention.

List of figures of drawings and other materials
The invention will be described by way of example with reference to the attached drawings, where
in FIG. 1 is a schematic axonometric view of the bow of a vessel illustrating an embodiment of the invention;
in FIG. 2.1 is a perspective view of a vessel showing the location of an inlet and several outlets in accordance with an embodiment of the present invention;
in FIG. 2.2 is a diagram showing the difference in water pressure in the inlet and in each of the outlets shown in FIG. 2.1;
in Fig.3.1 and 3.2 presents types of sections illustrating the process of exchange of ballast water in accordance with an embodiment of the invention;
4 is a schematic illustration of a test device for illustrating the exchange of water in a ballast tank; and
in FIG. 5 is a graph illustrating measurement results of changes in salt concentration in a tank using the device shown in FIG. 4.

Information confirming the possibility of carrying out the invention
In FIG. 1 and 2, a vessel 5 is shown having several ballast tanks 6 located on both sides thereof. The water inlet (inlet) hole 11 is located in that place of the bow of the vessel 5, which is normally below the water level 8 when the vessel 5 moves forward in the water, as shown in FIG. 1. Window 11 diverges with a cone, which contributes to the natural entry of sea water into the hole 11 when the vessel 5 moves forward.

 The water supply channel to the ballast tank under a pressure greater than the pressure of the ballast water in the tank, displacing the ballast water from the ballast tank through said outlet, for example a steel pipe 12, passes from the hole 11 through the ballast tanks 6, as shown in FIG. 1 . The channel has a branch 12.1, due to which it passes through the ballast tanks 6 on both sides of the vessel 5.

 Each ballast tank 6 has a water inlet 13 on the pipe 12 for inlet of water into the tank 6. As shown, the inlet 13 is located on one side of the tank 6. Each inlet 13 has a valve 13.1 for opening and closing the inlet 13.

 Each ballast tank 6 additionally has a water outlet (outlet) 14 and a valve 14.1 for opening and closing the outlet 14. As shown, the outlet 14 is located in front of the inlet 13 relative to the direction of movement of the vessel and in the bottom of the ballast tank 6 at the opposite end of the tank 6, so that it is located at the farthest point from the water inlet 13.

 In the hole 11 there is a valve 11.1 for opening and closing, if necessary, the hole 11.

 Since the inlet 11 is located in such a place that the water pressure acting on the moving vessel is increased, for example, at a point below the water level 8 in front of the bow of the vessel 5, a pressure difference, or a difference in water pressure, between the inlet 11 and the outlet 14. This allows you to supply water to the ballast tank 6 without the cost of additional energy for pumping water from the inlet to the tank 6.

 Due to the difference in pressure, water from the inlet 11 enters through the inlet 13 on one side of the ballast tank 6, pushing the dirty ballast water in the tank 6 and requiring replacement, to the other side of the tank 6 and forcing the water through the outlet 14. Thus, contaminated ballast water is replaced with fresh water when moving across the sea.

 Normally, valve 11.1 is in the closed state, preventing water from entering the inlet 11. Before starting the water replacement process, valve 14.1 opens. As a result, water from the tank 6 flows out under the action of gravity and its level decreases in accordance with the level of draft of the vessel, as shown in figure 3.1.

 Next, valves 11.1 and 13.1 open. When this water enters the ballast tank 6 under pressure through the pipe 12 from the inlet 11.

 Since the water pressure in the pipe 12 at the inlet 13 is approximately equal to the pressure at the inlet 11 and higher than the pressure of the ballast water in the tank 6, the water in the tank 6 is pushed to the opposite side of the tank 6 and is forced out through the outlet 14, as shown in FIG. .3.2.

 After the contaminated ballast water has been replaced with fresh seawater, valves 11.1, 13.1 and 14.1 are closed and the water change process is completed. If necessary or desired, the amount of water in the tank 6 can be brought to the desired level using a pump.

 The description given refers to one ballast tank 6. However, the same operation can be done with any of the other ballast tanks 6, where dirty ballast water is required to be replaced. For this purpose, water outlets can be made in different places of the vessel 5, as, for example, shown by digital designations 141, 142, 143 and 144 in figure 2.1. An example of a difference in water pressure between the inlet 11 and the outlet openings 141-144 is shown in FIG. 2.2.

EXPERIMENTAL CHECK
In order to demonstrate the replacement, namely the replacement of ballast water in the ballast tank due to the difference in water pressure without the use of additional energy, the following experiment was carried out.

 The experimental device is shown in figure 4. To create a water pressure corresponding to the pressure at the inlet 11, a reservoir 21 is used. Fresh water is poured into the reservoir 21. In the reservoir 21 there is, as shown, an overflow hole. There is a sealed tank 22 corresponding to the ballast tank 6. The tank 22 is filled with salt water and inside the tank there are several points 1-9 measuring salt concentration. There is also a reservoir 23 for generating water pressure simulating the pressure at the outlet 14. In the reservoir 23 there is an overflow hole. The tanks 21 and 22 are connected by a channel 24 for water. In addition, the reservoirs 22 and 23 are connected by a channel 25 for water.

 Checking the water exchange is performed by setting the water level in the tank 21 above the water level in the tank 22 and setting the water level in the tank 23 below the water level in the tank 22. Fresh water is supplied to the tank 22 from the tank 21 under the influence of the difference in water levels. Salt concentration is measured at different points 1-9 of the measurement of salt concentration in tank 22.

 The dependence of the change in salt concentration on time at each of the points 1-9 for measuring salt concentration under the action of a pressure difference of water, corresponding to the pressure difference when the vessel is moving at a speed of 15 knots, is shown in FIG. The salt concentration drops to about a quarter of the original value after sixty minutes, indicating that about three quarters of the water in the tank 22 has been replaced.

 The invention is not limited to the embodiments described above, and, of course, various modifications thereof are possible within the scope of the claims of the invention. For example, in the embodiment described above, the inlet 11 is made below the water level in the front of the bow of the vessel, where the pressure of the water on the vessel during movement is maximum. However, the invention is not limited to this, and the inlet can be made in other places, provided that the pressure there is higher than the pressure of the water in the ballast tank 6.

 Further, in the above embodiment, the channel 12 branches and connects to each of the ballast tanks 6 on both sides of the vessel. However, the invention is not limited to such a configuration, and several inlet channels 12 can be used, according to the number of ballast tanks 6, and each of several inlet channels 12 is connected to each of the ballast tanks 6. Thus, unlike the case with a branched inlet channel 12, replacement water may be supplied to each of the ballast tanks under the same pressure.

 The advantage of the invention is that the replacement of ballast water in the ballast tank can be performed without the use of an energy source, in addition to energy obtained from the movement of the vessel, thereby not requiring energy costs to replace ballast water. In addition, an operator is not needed to control energy use, which further reduces costs.

 Although only preferred embodiments of the invention are described in detail here, the invention is not limited to them and is subject to change within the scope of the appended claims.

Claims (5)

1. The method of replacing ballast water in the ballast tank of a vessel, characterized in that the water is supplied through a water inlet located in the part of the vessel, on which the pressure of the water acting on the vessel when it moves forward in the water is higher than the pressure to be replaced ballast water, then carry out the supply of said water with a higher pressure from the water inlet to the ballast tank by connecting said water inlet with a ballast tank containing w replacing ballast water, and the displacement is carried out ballast water from the ballast tanks and ballast water replacement water from the water inlet hole by using the difference of the water pressure the higher pressure coming from said water inlet opening and the ballast water. 2. The method according to claim 1, characterized in that the water supply is carried out through a water inlet located in front of the bow of the vessel. 3. A device for replacing ballast water in a ship’s ballast tank, including a water inlet located in the part of the ship on which the pressure of the water pressure acting on the ship when it moves forward in the water exceeds the pressure value of the ballast water to be replaced, water outlet in the ballast tank and a water inlet for supplying water to the ballast tank under a pressure greater than the pressure of the ballast water in the tank, with the ballast water being displaced from the ballast tank through said water outlet an opening, said said water inlet being located between said water inlet and said ballast tank. 4. The device according to claim 3, characterized in that the said water inlet is located in front of the bow of the vessel. 5. The device according to claim 3, characterized in that the said water inlet is connected via a water inlet to a group of ballast tanks of the vessel.

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