WO2010046906A2

WO2010046906A2 - Method and system for managing ballast water

Info

Publication number: WO2010046906A2
Application number: PCT/IN2009/000496
Authority: WO
Inventors: Virendra J. Mehta
Original assignee: Mehta Virendra J
Priority date: 2008-09-16
Filing date: 2009-09-10
Publication date: 2010-04-29
Also published as: WO2010046906A3

Abstract

The present invention describes a method and system for managing ballast water in a sea vessel. The method includes purifying ballast water while filling one or more ballast tanks of the sea vessel in shallow water and exchanging ballast water in deep water, whereby exchanging ballast water includes filling and discharging ballast water in one or more ballast tanks of the sea vessel. The one or more ballast tanks of the sea vessel are filled with ballast water through an inlet at a first pre- determined pressure level. Simultaneous to filling one or more ballast tanks of the sea vessel, ballast water is discharged from one or more ballast tanks through an outlet at a second pre-determined pressure level.

Description

METHOD AND SYSTEM FOR MANAGING BALLAST WATER

FIELD OF THE INVENTION

[0001] The invention generally relates to management of ballast water in a sea vessel. More specifically, the invention relates to a ballasting and deballasting process involving purification of ballast water in the sea vessel.

BACKGROUND OF THE INVENTION

[0002] A sea vessel is used to carry cargo from one port to another. During transportation of cargo between ports, it may happen that the sea vessel returns empty after unloading its cargo at a first port. This may lead to instability of the sea vessel due to change in overall weight of the sea vessel. To maintain stability after unloading cargo, sea water is filled into one or more ballast tanks of the sea vessel. Sea water filled in one or more ballast tanks of the sea vessel is known as ballast water. Ballast water provides the sea vessel with stability and structural integrity. Also, ballast water helps in submergence of propeller and rudder of the sea vessel. Ballast water thereby increases maneuverability of the sea vessel and reduces amount of exposed surface of a hull of the sea vessel. The sea vessel discharges ballast water when cargo is loaded at a second port.

[0003] During filling of ballast water, species of bacteria, plants and animals may be picked up in ballast water and these may sustain in one or more ballast tanks of the sea vessel for a long duration. Therefore, these may get released to the second port while discharging of ballast water into water of the second port. This may result in upsetting ecological balance of sea water. It is therefore important to ensure that minimum living organisms are transported along with ballast water to another port.

[0004] Research has shown that living organisms present in shallow water of a port cannot survive in deep water because of different environmental conditions and vice-a-versa. Considering the above, International Maritime Organization (IMO) has recommended for exchanging ballast water of sea vessels in deep sea. [0005] One of the prevailing methods used for ballast water exchange as recommended by the IMO is a sequential method. In the sequential method, one or more ballast tanks of the sea vessel are emptied and then refilled. The sequential method removes large weights from the sea vessel in the form of ballast water before replacing those weights by filling in new ballast water. This may lead to over and under pressurization of one or more ballast tanks. The sequential method also generates free surface effect which may affect stability of the sea vessel. Further, the sequential method may result in excessive shearing forces, torsional forces and bending moments being applied to the sea vessel.

[0006] Another method commonly used for ballast water exchange is a flow-through method. In the flow-through method, one or more ballast tanks of the sea vessel are overfilled by pumping in additional water. Subsequently, additional water is made to overflow through ventilator pipes and manholes of the sea vessel. The flow-through method leads to over pressurization of one or more ballast tanks causing over stressing of hull girder of the sea vessel. Also, large volumes of ballast water overflowing on to deck of the sea vessel may cause serious safety risks for crew members and may interrupt routine, maintenance work. Additionally, the flow-through method may also lead to significant increase in corrosion of deck plating and fittings of the sea vessel.

[0007] There is therefore a need for management of ballast water in a sea vessel in a way that maintains overall stability of the sea vessel and ecological balance of sea water.

SUMMARY OF THE INVENTION

[0008] An objective of the invention is to provide a method and system for maintaining overall stability of a sea vessel during ballast water exchange.

[0009] Another objective of the invention is to provide a method and system for removing impurities including, but not limited to, sand, sediments, other deposits, bacteria and pathogens from ballast water.

[0010] Another objective of the invention is to provide a method and system for safely performing ballast water exchange. [0011] Yet another objective of the invention is to provide a method and system for performing ballast water exchange at a low maintenance cost.

[0012] The above listed and various other objectives are achieved by providing a method and system for managing ballast water in a sea vessel. The method includes exchanging ballast water by using a filling ballast pipeline fitted in one or more ballast tanks of a sea vessel. The method uses pressure difference for filling and discharging of one or more ballast tanks of the sea vessel. The method further includes purifying ballast water in a ballast tank of one or more ballast tanks of the sea vessel before pumping ballast water to fill other ballast tanks of the sea vessel.

BRIEF DESCRIPTION OF THE FIGURES

[0013] The accompanying figures, where like reference numerals refer to identical or functionally similar elements throughout the separate views and which together with the detailed description below are incorporated in and form part of the specification, serve to further illustrate various embodiments and to explain various principles and advantages all in accordance with the invention.

[0014] FIG. 1 illustrates a longitudinal section view of a sea vessel.

[0015] FIG. 2 illustrates a transverse section view corresponding to axis A-A' in FIG. 1.

[0016] FIG. 3 illustrates a transverse section view corresponding to axis B-B' in FIG 1.

[0017] FIG. 4 illustrates a cross section view of a sea vessel showing a ballast water pumping system in accordance with an embodiment of the invention.

[0018] FIG. 5 illustrates a transverse section view of a sea vessel showing a ballast water pumping system in accordance with an embodiment of the invention. [0019] FIG. 6 illustrates a longitudinal section view of a sea vessel showing purification assembly in accordance with an embodiment of the invention.

[0020] FIG. 7 illustrates a transverse section view of a sea vessel showing purification assembly in accordance with an embodiment of the invention.

[0021] FIG. 8 illustrates a transverse section view of a sea vessel showing baffle plate arrangement in accordance with an embodiment of the invention.

[0022] Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the invention.

DEFINITIONS

[0023] Ballast tank: It is a compartment within a sea vessel that holds water.

[0024] Double Bottom Segregated Ballast tank: It is a compartment within a sea vessel that is divided by the floors and keelsons between inner and outer bottom of the sea vessel.

[0025] Side Segregated Ballast tank: These ballast tanks are located on either side of a sea vessel providing protection to cargo tanks in case of collision.

[0026] After peak ballast tank: It is an enclosed space immediately forward of the sternpost and aft of the aftermost watertight bulkhead of a sea vessel.

[0027] Fore peak ballast tank: It is an enclosed space immediately forward of the fore collision bulkhead of a sea vessel.

[0028] Bow: It refers to the forward part of the hull of a sea vessel, the point that is most forward when the sea vessel is underway. [0029] Stern: It is the rear or aft part of a sea vessel, technically defined as the area built up over the sternpost, extending upwards from the counter to the taffrail. The stern lies opposite of the bow, the foremost part of the sea vessel.

[0030] Keel: It is a large beam around which the hull of a sea vessel is built. The keel runs in the middle of the sea vessel, from the bow to the stern, and serves as the foundation or spine of the sea vessel structure, providing major source of structural strength to the hull. It is the lowest part of the sea vessel.

[0031] Draft: It is the vertical distance between the waterline and keel of a sea vessel. Draft determines the minimum depth of water the sea vessel can safely navigate.

[0032] Hull: It is the body of a sea vessel. It is a central concept in sea vessels as it provides the buoyancy that keeps the sea vessel from sinking.

[0033] Starboard side: It refers to the right side of a sea vessel as perceived by a person on board the sea vessel and facing the bow.

[0034] Port Side: It refers to the left side of a sea vessel as perceived by a person on board the sea vessel and facing the bow.

[0035] Sea chest: It is an opening in the hull of a sea vessel on either sides for the purpose of ballasting and deballasting the ballast tanks of the sea vessel.

[0036] Bulkhead: It is a division or partition that divides a sea vessel into compartments, increases structural rigidity and prevents spreading of leakage or fire.

[0037] Bell mouth: It is a bell shaped opening in a pipeline located inside a ballast tank of a sea vessel and fitted with valve. It is used either as a suction inlet or discharge outlet for ballasting or deballasting the ballast tanks of the sea vessel. DETAILED DESCRIPTION OF THE INVENTION

[0038] Before describing in detail embodiments that are in accordance with the invention, it should be observed that the embodiments reside primarily in combinations of method steps and system components related to method and system for managing ballast water. Accordingly, the system components and method steps have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.

[0039] In this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises ...a" does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0040] Generally speaking, pursuant to various embodiments, the invention provides a method and system for managing ballast water.

[0041] FIG. 1 illustrates a longitudinal section view of a sea vessel 100. Sea vessel 100 includes a fore peak ballast tank 102, a bow 104, a stern 106, an after peak ballast tank 112, a machinery space 114, a pump room ϊ 16 and one or more transverse bulkheads 118-n. Bow 104 is forward most part of a hull of sea vessel 100. Stern 106 is rear most part of the hull of sea vessel 100. Fore peak ballast tank 102 located in forward part of sea vessel 100 and after peak ballast tank 112 located in rear part of sea vessel 100 are used for storing ballast water. Transverse bulkheads 118-n partition sea vessel 100 into one or more compartments. As shown in FIG. 1, transverse bulkheads 118-n can be for example, a transverse bulkhead 118-1, a transverse bulkhead 118-2 and a transverse bulkhead 118-3.

[0042] FIG. 2 illustrates a transverse section view corresponding to axis A-A' of sea vessel 100 as shown in FIG. 1. Sea vessel 100 includes one or more side segregated ballast tanks 202-n, one or more side cargo tanks 204-n, one or more center cargo tanks 206-n and one or more longitudinal bulkheads 208-n. Also, FIG. 2 depicts various elements from FIG. 1 in accordance with the invention. Center cargo tanks 206-n and side cargo tanks 204-n are used for storing cargo. Center cargo tanks 206-n are located along central longitudinal axis of the hull of sea vessel 100. Center cargo tanks 206-n can be, for example, a center cargo tank 206-1 and a center cargo tank 206-2. Also as depicted, side cargo tanks 204-n are located on both sides of sea vessel 100 adjoining center cargo tanks 206-n. Side cargo tanks 204-n extend from main deck level to bottom level of center cargo tanks 206-n. Side cargo tanks 204-n can be, for example, a side cargo tank 204-1 and a side cargo tank 204-2. Further, side segregated ballast tanks 202-n are located on both sides of sea vessel 100 for storing ballast water. Side segregated ballast tanks 202-n extend from main deck level to bottom level of center cargo tanks 206-n. Side segregated ballast tanks 202-n can be, for example, a side segregated ballast tank 202-1 and a side segregated ballast tank 202-2. Longitudinal bulkheads 208-n partition sea vessel 100 into one or more compartments. As shown in FIG. 2, longitudinal bulkheads 208-n can be, for example, a longitudinal bulkhead 208-1 and a longitudinal bulkhead 208-2.

[0043] FIG. 3 illustrates a transverse section view corresponding to axis B-B' of sea vessel 100 as shown in FIG. 1. Sea vessel 100 includes one or more double bottom segregated ballast tanks 302-n. Also, FIG. 3 depicts various elements from FIG. 1 in accordance with the invention. Double bottom segregated ballast tanks 302-n extend below center cargo tanks 206-n, side cargo tanks 204-n and side segregated ballast tanks 202-n (as shown in FIG. 2). Double bottom segregated ballast tanks 302-n are used for storing ballast water. As shown in FIG. 3, double bottom segregated ballast tanks 302-n can be, for example, a double bottom segregated ballast tank 302-1 and a double bottom segregated ballast tank 302-2.

[0044] FIG. 4 illustrates a cross section view of sea vessel 100 showing a ballast water pumping system in accordance with an embodiment of the invention. One or more of double bottom segregated ballast tanks 302-n (as shown in FIG. 3) are dedicated for filtration and treatment of ballast water while filling ballast water in one or more double bottom segregated ballast tanks 302-n. Such double bottom segregated ballast tanks dedicated for filtration and treatment of ballast water are called dedicated double bottom segregated ballast tanks. Sea vessel 100 includes a dedicated double bottom segregated ballast tank 302-3 and a dedicated double bottom segregated ballast tank 302-4. Dedicated double bottom segregated ballast tank 302-3 and dedicated double bottom segregated ballast tank 302-4 are used for filtering ballast water before channeling ballast water to other ballast tanks. Also, sea vessel 100 includes a side segregated ballast tank 202-3, a side segregated ballast tank 202-4, a side cargo tank 204-3, a side cargo tank 204-4 and a center cargo tank 206-3. Sea vessel 100 is divided into a port side and a starboard side of sea vessel 100 by a center girder 401. In FIG. 4 dedicated double bottom segregated ballast tank 302-3, side segregated ballast tank 202-3 and side cargo tank 204-3 are located on the port side of sea vessel 100. Dedicated double bottom segregated ballast tank 302-4, side segregated ballast tank 202-4 and side cargo tank 204-4 are located on the starboard side of sea vessel 100.

[0045] Further, sea vessel 100 includes a port side sea chest 402 and a starboard side sea chest 404 located in pump room 116. hi an embodiment of the invention, port side sea chest 402 has a grating or a wire meshing to avoid entry of big fish, debris and other obstructions in sea vessel 100. Port side sea chest 402 is controlled by a valve system which may be operated by various means such as manual and hydraulic. Sea vessel 100 also includes a sea chest ballast pipeline 406, an intermediate ballast pipeline 408 and a filling ballast pipeline 410 to facilitate ballasting and deballasting of sea vessel 100. Sea chest ballast pipeline 406 is located in pump room 116 (not shown in FIG. 4) extending from port side sea chest 402 to starboard side sea chest 404. Filling ballast pipeline 410 is connected to sea chest ballast pipeline 406 through intermediate ballast pipeline 408. Filling ballast pipeline 410 extends to top of side segregated ballast tank 202-3 and side segregated ballast tank 202-4.

[0046] A T-shape connector 411 is connected to sea chest ballast pipeline 406. T-shape connector 411 connects sea chest ballast pipeline 406 to dedicated double bottom segregated ballast tank 302- 3. T-shape connector 411 is located at an aft bulkhead close to dedicated double bottom segregated ballast tank 302-3. T-shape connector 411 includes a bell mouth opening 412 located near top of dedicated double bottom segregated ballast tank 302-3. Bell mouth opening 412 is used as an inlet for filling dedicated double bottom segregated ballast tank 302-3. Filling ballast pipeline 410 fills side segregated ballast tank 202-3 through an inlet depicted as a bell mouth opening 414. Bell mouth opening 414 is located near top of side segregated ballast tank 202-3. Bell mouth opening 414 is located at end of an elbow bend in filling ballast pipeline 410. The elbow bend in filling ballast pipeline 410 is located at forward section of side segregated ballast tank 202-3 with the elbow bend facing towards a forward bulkhead in side segregated ballast tank 202-3.

[0047] Further, intermediate ballast pipeline 408 includes a bell mouth opening 416 located at an after section of dedicated double bottom segregated ballast tank 302-3. Bell mouth opening 416 is located near bottom of dedicated double bottom segregated ballast tank 302-3. In this embodiment of the invention, bell mouth opening 416 is used as an outlet to discharge dedicated double bottom segregated ballast tank 302-3. Similarly, intermediate ballast pipeline 408 includes a bell mouth opening 418 located in side segregated ballast tank 202-3. Bell mouth opening 418 is located near bottom of side segregated ballast tank 202-3 and is used for discharging side segregated ballast tank 202-3. In an example, bell mouth opening 418 is located near bottom of side segregated ballast tank 202-3 with a clearance of 15 to 20 mm for effective discharging of side segregated ballast tank 202- 3.

[0048] Additionally, sea vessel 100 also includes a ballast pump 420 and a ballast pump 422 located in pump room 116. Ballast pump 420 and ballast pump 422 are utilized for ballasting and deballasting during deep sea ballast water exchange. In an embodiment of the invention, only one ballast pump is used at a time for deep sea ballast water exchange in sea vessel 100. In another embodiment of the invention, ballast pump 420 and ballast pump 422 are used to pump filtered ballast water from dedicated double bottom segregated ballast tank 302-3 and dedicated double bottom segregated ballast tank 302-4 respectively to the other ballast tanks. Ballast pump 420 pumps out filtered ballast water stored in dedicated double bottom segregated ballast tank 302-3 through a bell mouth opening 424 located in dedicated double bottom segregated ballast tank 302-3. Filtered ballast water is thereafter channeled to the other ballast tanks. In an embodiment of the invention, filtered ballast water is treated with Ultra Violet (UV) radiations radiated from a UV radiation unit 426 located near ballast pump 420. Thereafter, filtered ballast water treated with UV radiations is channeled to the other ballast tanks.

[0049] Similarly, sea vessel 100 includes a bell mouth opening 428 and a bell mouth opening 430 located in after peak ballast tank 112. Bell mouth opening 428 is used as an outlet for discharging after peak ballast tank 112. Bell mouth opening 430 is used as an inlet for filling ballast water in after peak ballast tank 112.

[0050] In an embodiment of the invention, lower surface of side segregated ballast tank 202-3 and adjoining top surface of dedicated double bottom segregated ballast tank 302-3 are sealed to avoid any direct interconnectivity between side segregated ballast tank 202-3 and dedicated double bottom segregated ballast tank 302-3. However, side segregated ballast tank 202-3 is indirectly interconnected to dedicated double bottom segregated ballast tank 302-3 through intermediate ballast pipeline 408. Side segregated ballast tank 202-4 and dedicated double bottom segregated ballast, tank 302-4 are interconnected in a similar way as side segregated ballast tank 202-3 and dedicated double bottom segregated ballast tank 302-3. In this embodiment of the invention, in order to carry out ballasting of dedicated double bottom segregated ballast tank 302-3 in deep sea, deep sea water is filled into dedicated double bottom segregated ballast tank 302-3 through port side sea chest 402. Deep sea water is then channeled through sea chest ballast pipeline 406 located in pump room 116. Ballast water is subsequently channeled to T-shape connector 411 located in dedicated double bottom segregated ballast tank 302-3. Deep sea water is then filled in dedicated double bottom segregated ballast tank 302-3 through bell mouth opening 412 present in T-shape connector 411. Gravitational force is used to guide deep sea water from port side sea chest 402 to bell mouth opening 412. Simultaneous to ballasting dedicated double bottom segregated ballast tank 302-3, deballasting of dedicated double bottom segregated ballast tank 302-3 is carried out to keep quantity of ballast water stored in dedicated double bottom segregated ballast tank 302-3 unchanged. Ballasting and deballasting dedicated double bottom segregated ballast tank 302-3 simultaneously helps in maintaining stability of sea vessel 100. In order to carry out deballasting of dedicated double bottom segregated ballast tank 302-3, ballast water is sucked from bell mouth opening 416 located near bottom of dedicated double bottom segregated ballast tank 302-3. Ballast water is then channeled through intermediate ballast pipeline 408 and subsequently made to exit sea vessel 100 through starboard side sea chest 404. Ballasting and deballasting of dedicated double bottom segregated ballast tank 302-4 is performed in a similar way as ballasting and deballasting of dedicated double bottom segregated ballast tank 302-3.

[0051] Considering an example where height of dedicated double bottom segregated ballast tank 302-3 and dedicated double bottom segregated ballast tank 302-4 is 3.0 meters. Height of side segregated ballast tank 202-3 and side segregated ballast tank 202-4 is 27.0 meters. Draft of sea vessel 100 is 10.0 meters. Width of sea vessel 100 at a cross section at middle of sea vessel 100 is 60.0 meters. Port side sea chest 402 is at a pressure level created by 10.0 meters draft. Height of ballast water stored in dedicated double bottom segregated ballast tank 302-3 and dedicated double bottom segregated ballast tank 302-4 is approximately 3.0 meters. Depth of sea water is approximately 200 meters in deep sea. Thus, port side sea chest 402 is at higher pressure because of 10.0 meters draft. Hence, deep sea water moves from port side sea chest 402 to bell mouth opening 412 due to gravitational force. Simultaneous to filling of dedicated double bottom segregated ballast tank 302-3, ballast water stored in dedicated double bottom segregated ballast tank 302-3 is discharged through bell mouth opening 416. Bell mouth opening 416 is located near bottom of dedicated double bottom segregated ballast tank 302-3. Bell mouth opening 416 is at a pressure level created by approximately 3.0 meters of ballast water stored in dedicated double bottom segregated ballast tank 302-3. Starboard side sea chest 404 is at a pressure level created by 10.0 meters draft. A first pre-determined pressure is thus created at bell mouth opening 416 by operating ballast pump 422 to discharge ballast water stored in dedicated double bottom segregated ballast tank 302-3 through bell mouth opening 416. The first pre-determined pressure is adjusted such that quantity of ballast water stored in dedicated double bottom segregated ballast tank 302-3 remains unchanged. Ballast water is then channeled through intermediate ballast pipeline 408 and subsequently made to exit sea vessel 100 at starboard side sea chest 404.

[0052] In the above embodiment of the invention, in order to carry out ballasting of side segregated ballast tank 202-3 in deep sea, deep sea water is filled into side segregated ballast tank 202-3 through port side sea chest 402. Deep sea water is pumped into sea chest ballast pipeline 406 using ballast pump 420. Deep sea water is then channeled through filling ballast pipeline 410 to bell mouth opening 414 in side segregated ballast tank 202-3. Simultaneous to ballasting of side segregated ballast tank 202-3, deballasting of side segregated ballast tank 202-3 is carried out to keep quantity of ballast water stored in side segregated ballast tank 202-3 unchanged. Ballasting and deballasting side segregated ballast tank 202-3 simultaneously helps in maintaining stability of sea vessel 100. In order to carry out deballasting of side segregated ballast tank 202-3, ballast water stored in side segregated ballast tank 202-3 is discharged through bell mouth opening 418 located near bottom of side segregated ballast tank 202-3. Ballast water is then channeled through intermediate ballast pipeline 408. Subsequently, ballast water is made to exit sea vessel 100 through starboard side sea chest 404. Gravitational force is used to guide ballast water stored in side segregated ballast tank 202-3 from bell mouth opening 418 to starboard side sea chest 404. Ballasting and deballasting of side segregated ballast tank 202-4 is performed in a similar way as ballasting and deballasting of side segregated ballast tank 202-3.

[0053] For example, bell mouth opening 418 located in side segregated ballast tank 202-3 is at a pressure level created by approximately 27.0 meters height of ballast water stored in side segregated ballast tank 202-3. Starboard side sea chest 404 is at a pressure level created by 10.0 meters draft. Bell mouth opening 418 is hence at higher pressure. Ballast water stored in side segregated ballast tank 202-3 thus moves from bell mouth opening 418 to starboard side sea chest 404 due to gravitational force. Ballast water is then channeled through intermediate ballast pipeline 408. Subsequently, ballast water is made to exit sea vessel 100 through starboard side sea chest 404. Bell mouth opening 414 located near top of side segregated ballast tank 202-3 is at pressure level approximately equal to atmospheric pressure. A second pre-determined pressure is thus created at bell mouth opening 414 by using ballast pump 420 to pump deep sea water in side segregated ballast tank 202-3 through port side sea chest 402. The second pre-determined pressure is adjusted such that quantity of ballast water stored in side segregated ballast tank 202-3 remains unchanged. Deep sea water is pumped-in through port side sea chest 402 and is channeled through sea chest ballast pipeline 406. Ballast water is then channeled through filling pipeline 410. Subsequently, deep sea water enters side segregated ballast tank 202-3 through bell mouth opening 414 located in side segregated ballast tank 202-3.

[0054] In another embodiment of the invention, a side segregated ballast tank and a double bottom segregated ballast tank are directly interconnected through one or more perforations present at bottom of the side segregated ballast tank. During ballasting of the side segregated ballast tank, deep sea water is pumped through port side sea chest 402 by using ballast pump 420. Deep sea water is then channeled through sea chest ballast pipeline 406 to filling ballast pipeline 410. Subsequently, deep sea water enters the side segregated ballast tank through a first bell mouth opening located near top of the side segregated ballast tank. Due to direct interconnectivity between the side segregated ballast tank and the double bottom segregated ballast tank through one or more perforations at bottom of the side segregated ballast tank, ballasting of the side segregated ballast tank and the double bottom segregated ballast tank occurs simultaneously. During deballasting of the side segregated ballast tank, ballast water is discharged from the side segregated ballast tank through one or more perforations present at bottom of the side segregated ballast tank due to gravitational force. Ballast water is then channeled through a second bell mouth opening located in the double bottom segregated ballast tank. Subsequently, ballast water is channeled through intermediate ballast pipeline 408 and made to exit sea vessel 100 through starboard side sea chest 404. Due to direct interconnectivity between the side segregated ballast tank and the double bottom segregated ballast tank through one or more perforations at bottom of the side segregated ballast tank, deballasting of the side segregated ballast tank and the double bottom segregated ballast tank occurs simultaneously.

[0055] Deep sea ballast water exchange in fore peak ballast tank 102 and after peak ballast tank 112 is also carried out in a similar fashion as described in above embodiments of the invention. In an alternate embodiment of the invention, starboard side sea chest 404 is used as an entry point for filling ballast water in sea vessel 100 and port side sea chest 402 is used as an exit point for discharging ballast water from sea vessel 100.

[0056] FIG. 5 illustrates a transverse section view of sea vessel 100 showing a ballast water pumping system in accordance with an embodiment of the invention. Sea vessel 100 includes an overflow wall 502 and a filter wall 504. Also, FIG. 5 depicts various elements from FIG. 1, FIG. 2, FIG. 3 and FIG. 4 in accordance with the invention. Further, FIG. 5 also depicts bell mouth openings corresponding to other side segregated ballast tanks for filling of the other side segregated ballast tanks, as, a bell mouth opening 414-1, a bell mouth opening 414-2, a bell mouth opening 414-3 and a bell mouth opening 414-4. Also, bell mouth openings corresponding to other double bottom segregated ballast tanks for discharging the other double bottom segregated ballast tanks are depicted as a bell mouth opening 416-1, a bell mouth opening 416-2, a bell mouth opening 416-3 and a bell mouth opening 416-4.

[0057] In an embodiment of the invention, overflow wall 502 is located in dedicated double bottom segregated ballast tank 302-3 and dedicated double bottom segregated ballast tank 302-4. Overflow wall 502 is fitted across breadth of dedicated double bottom segregated ballast tank 302-3 and dedicated double bottom segregated ballast tank 302-4. Height of overflow wall 502 is less than height of dedicated double bottom segregated ballast tank 302-3 and dedicated double bottom segregated ballast tank 302-4. Overflow wall 502 is located close to T-shape connector 411 in dedicated double bottom segregated ballast tank 302-3. Overflow wall 502 is built by modifying a first transverse web frame in dedicated double bottom segregated ballast tank 302-3. Overflow wall 502 functions as an overflow barrier for sea water filled in dedicated double bottom segregated ballast tank 302-3 and dedicated double bottom segregated ballast tank 302-4 at a port. Overflow wall 502 is used to arrest one or more contaminating matter present in port side sea water during filling of dedicated double bottom segregated ballast tank 302-3 and dedicated double bottom segregated ballast tank 302-4 at the port. Port side sea water thus overflows across overflow wall 502 and is thereafter passed through filter wall 504. Filter wall 504 is located in dedicated double bottom segregated ballast tank 302-3 and dedicated double bottom segregated ballast tank 302-4. Filter wall 504 is used to filter port side sea water overflowing across overflow wall 502 before channeling of port side sea water to the other ballast tanks. Filter wall 504 is fitted across complete breadth and complete height of dedicated double bottom segregated ballast tank 302-3 and dedicated double bottom segregated ballast tank 302-4. Filter wall 504 is built by modifying a second transverse web frame in double bottom segregated ballast tank 302-3. Filter wall 504 includes filtering materials like charcoal, pebbles, ceramic, etc. In another embodiment of the invention, filter wall 504 includes a membrane. Filter wall 504 is used to filter out one or more contaminating matter like sand, sediments and some percentage of bacteria and pathogens present in port side sea water.

[0058] In another embodiment of the invention, a series of perforated high pressure air pipes are provided to prevent a blockage or clogging of filter wall 504. The high pressure air pipes are blown through at periodic intervals with high pressure air for effectively removing the blockage or clogging of filter pores of filter wall 504. In addition, high pressure water jets or sprinklers are also fitted at strategic locations for cleaning filter wall 504 and diverting sand deposits to bell mouth opening 416 of dedicated double bottom segregated ballast tank 302-3.

[0059] FIG. 6. illustrates a longitudinal section view of sea vessel 100 showing purification assembly in accordance with an embodiment of the invention. Sea vessel 100 includes a compartment 602, a compartment 604 and an ozonation unit 606. Also, FIG. 6 depicts various elements from FIG. 3, FIG. 4 and FIG. 5 in accordance with the invention. Overflow wall 502 and filter wall 504 are located in compartment 602 of dedicated double bottom segregated ballast tank 302-3. Ozonation unit 606 is located in compartment 604 of dedicated double bottom segregated ballast tank 302-3 and is used to treat port side sea water.

[0060] In an embodiment of the invention, sea vessel 100 arrives at a port in a fully loaded condition. After arriving at the port, sea vessel 100 is unloaded by removing stored cargo. In order to maintain stability of sea vessel 100, port side sea water is filled in one or more ballast tanks of sea vessel 100 simultaneous to unloading of sea vessel 100. Port side sea water enters sea vessel 100 through T-shape connector 411. Bell mouth opening 412 in T-shape connector 411 is used as an inlet to fill dedicated double bottom segregated ballast tank 302-3. Gravitational force is used to guide port side sea water from port side sea chest 402 to bell mouth opening 412. Port side sea water is then purified in double bottom segregated ballast tank 302-3 while filling dedicated double bottom segregated ballast tank 302-3. Overflow wall 502 arrests one or more contaminating matter present in port side sea water by functioning as a barrier for one or more contaminating matter. Port side sea water then flows from above overflow wall 502 and passes through filter wall 504. Filtered port side sea water is thus collected in compartment 604 of dedicated double bottom segregated ballast tank 302-3. Compartment 604 is used as a storage tank to store and treat port side sea water. Compartment 604 acts as a huge reservoir to continuously feed port side sea water to the other ballast tanks of sea vessel 100. Ozonation unit 606 is used to treat filtered port side sea water collected in compartment 604. Subsequently filtered and ozone treated port side sea water is channeled to the other ballast tanks of sea vessel 100. Port side sea water is similarly filtered and treated in dedicated double bottom segregated ballast tank 302-4.

[0061] In another embodiment of the invention, filtration and treatment of port side sea water is done in one or more of the other ballast tanks of sea vessel 100.

[0062] FIG. 7 illustrates a transverse section view of sea vessel 100 showing purification assembly in accordance with an embodiment of the invention. Sea vessel 100 includes a suction ballast pipeline 702 and a discharge ballast pipeline 704. Also, FIG. 7 depicts various elements from FIG. 3, FIG. 4, FIG. 5 and FIG. 6 in accordance with the invention. A first end in suction ballast pipeline 702 includes a bell mouth opening 424 and a second end of suction ballast pipeline 702 is connected to ballast pump 420. Bell mouth opening 424 is located in dedicated double bottom segregated ballast tank 302-3. Discharge ballast pipeline 704 is connected to ballast pump 420 on a first end and intermediate ballast pipeline 408 on a second end. Ballast pump 420 sucks filtered and ozone treated ballast water stored in dedicated double bottom segregated ballast tank 302-3 through bell mouth opening 424. Thereafter, ballast water is channeled through suction ballast pipeline 702 and then through discharge ballast pipeline 704. Subsequently, discharge ballast pipeline 704 is used for channeling filtered and ozone treated ballast water pumped by ballast pump 420 to the other ballast tanks through intermediate ballast pipeline 408. UV radiation unit 426 is located in discharge ballast pipeline 704. UV radiation unit 426 is used to treat filtered and ozone treated ballast water in discharge ballast pipeline 704.

[0063] In another embodiment of the invention, UV radiation unit 426 is located in one or more of dedicated double bottom segregated ballast tank 302-3, dedicated double bottom segregated ballast tank 302-4, the other ballast tanks, sea chest ballast pipeline 406, intermediate ballast pipeline 408, filling ballast pipeline 410 and suction ballast pipeline 702 of sea vessel 100. [0064] In another embodiment of the invention, ozonation unit 606 is located in one or more of the other ballast tanks, sea chest ballast pipeline 406, intermediate ballast pipeline 408, filling ballast pipeline 410, suction ballast pipeline 702 and discharge ballast pipeline 704 of sea vessel 100.

[0065] Consider an instance when sea vessel 100 arrives at a port in a fully loaded condition. Port side sea chest 402 is at a pressure level created due to 22.0 meters draft of sea vessel 100. Height of ballast water stored in dedicated double bottom segregated ballast tank 302-3 is approximately 3.0 meters. Thus, port side sea chest 402 is at higher pressure. Hence, port side sea water enters dedicated double bottom segregated ballast tank 302-3 through port side sea chest 402 due to gravitational force. Port side sea water is then channeled through sea chest ballast pipeline 406. Subsequently, port side sea water is channeled through T-shape connector 411 located in dedicated double bottom segregated ballast tank 302-3. Finally, dedicated double bottom segregated ballast tank 302-3 is filled through bell mouth opening 412 present in T-shape connector 411. Dense, heavy particles like sand, sediments and debris contained in port side sea water settles down by gravity at bottom of dedicated double bottom segregated ballast tank 302-3 near overflow wall 502. Overflow wall 502 is located in compartment 602 of dedicated double bottom segregated ballast tank 302-3. Overflow wall 502 is about 1.0 meter height and extends along complete breadth of dedicated double bottom segregated ballast tank 302-3. Subsequently, clear port side water rises and flows above overflow wall 502. Port side sea water then passes through filter wall 504. Thus port side sea water moves from compartment 602 to compartment 604. Compartment 602 contains unfiltered port side sea water and compartment 604 contains filtered port side sea water that has passed through filter wall 504. Compartment 604 has about 70% of total capacity of dedicated double bottom segregated ballast tank 302-3.

[0066] Ballast pump 420 is then used to suck filtered and ozone treated ballast water through suction ballast pipeline 702. Bell mouth 424 present in suction ballast pipeline 702 is located in dedicated double bottom segregated ballast tank 302-3. Bell mouth 424 is used as an inlet to channel filtered and ozone treated port side sea water from dedicated double bottom segregated ballast tank 302-3 to suction ballast pipeline 702 connected to ballast pump 420. Ballast pump 420 then discharges filtered and ozone treated port side sea water into discharge ballast pipeline 704 connected to ballast pump 420. Thereafter, filtered and ozone treated port side sea water is treated with UV radiations radiating from UV radiation unit 426 located in discharge ballast pipeline 704. UV radiation unit 426 radiates UV radiation at wavelength 254 nanometers, which alters genetic material in cells of one or more bacteria and microorganisms present in filtered and ozone treated port side sea water, such that one or more bacteria and microorganism cannot reproduce. UV radiation also removes residual ozone in filtered and ozone treated port side sea water. Filtered, ozone treated and UV radiation treated port side sea water is subsequently channeled through intermediate ballast pipeline 408 to the other ballast tanks of sea vessel 100.

[0067] FIG.8 illustrates a transverse section view of sea vessel 100 showing baffle plate arrangement in accordance with an embodiment of the invention. Sea vessel 100 includes one or more baffle plates 802-n, a flush plating 804 and one or more bottom longitudinals 806-n. Also, FIG. 8 depicts various elements from FIG 3, FIG. 4, and FIG. 5 in accordance with the invention. Baffle plates 802- n can be, for example, a baffle plate 802-1, a baffle plate 802-2 and a baffle plate 802-3. Baffle plates 802-n are located on overflow wall 502. Baffle plates 802-n are located near bottom of overflow wall 502. Baffle plates 802-n are controlled by hydraulic means and can be made to flip in open and close position. Baffle plates 802-n are in proximity to bell mouth opening 416 located near bottom of dedicated double bottom segregated ballast tank 302-3. At regular intervals of time, back flushing is performed in dedicated double bottom segregated ballast tank 302-3 to remove one or more contaminating matter accumulated near over flow wall 502 by using baffle plates 802-n. Further, flush plating 804 is bolted on top of bottom longitudinals 806-n of sea vessel 100. Flush plating 804 helps to avoid accumulation of sand and sediments at bottom longitudinals 806-n of dedicated double bottom segregated ballast tank 302-3. Thus, flush plating 804 facilitates effective removal of sand and sediments, thereby minimizing maintenance and inspection of lower section of dedicated double bottom segregated ballast tank 302-3. Flush plating 804 also keeps dedicated double bottom segregated ballast tank 302-3 clean which facilitates clear passage and drainage of sand and sediments towards bell mouth opening 416 located in dedicated double bottom segregated ballast tank 302-3 for effective removal by ballast pump 420.

[0068] In an embodiment of the invention, while filling dedicated double bottom segregated ballast tank 302-3, baffle plate 802-1 is flipped in close position for arresting one or more contaminating matter present in port side sea water like sand, sediments and debris. When one or more contaminating matter gets accumulated near over flow wall 502, back flushing is performed to remove one or more contaminating matter by using ballast pump 420. During back flushing, baffle plate 802-1 is flipped in open position and port side sea water along with the accumulated one or more contaminating matter is sucked into intermediate ballast pipeline 408 through bell mouth opening 416 located in dedicated double bottom segregated ballast tank 302-3. One or more contaminating matter is then discharged through port side sea chest 402.

[0069] In an example, baffle plate 806-1 is about 5.0 meters long and 1.0 meter in height. Flush plating 804 is of 20mm thickness and spreads on full breadth of dedicated double bottom segregated ballast tank 302-3 and extends to 30% of length of dedicated double bottom segregated ballast tank 302-3.

[0070] As a result of filtration and treatment of ballast water in dedicated double bottom segregated ballast tank 302-3, the other ballast tanks would have very few bacteria and pathogens that would have survived filtration, ozone treatment and UV treatment. Once circulated to the other ballast tanks of sea vessel 100, bacteria and pathogens are left with no sand, sediments and debris to survive on. In addition when filtered and treated ballast water undergoes ballast water exchange in deep sea, bacteria and pathogens are faced with totally different environmental underwater conditions of deep sea and hence their survival chances are highly reduced. Because of filtration and treatment process, bacteria and pathogens present in ballast water taken at a port are minimized. This reduces extent of ballast water exchange needed in deep sea. This decreases ballast pump running hours, wear and tear, and thus scales down running cost of sea vessel 100. Ballasting operations in port are judiciously controlled to allow sufficient time for filtering and treatment and at the same time match up with cargo discharging rate. This helps in maintaining the overall stability of sea vessel 100. Also, since multiple systems are used for treatment of ballast water, ballasting and deballasting of sea vessel 100 remains operational even if any one treatment system fails.

[0071] Sea vessel 100 may include all vessels which take in ballast water for the purpose of maintaining stability. Examples of sea vessel 100 may include, but are not limited to, an oil tanker, a chemical carrier, a gas tanker, a cargo carrier, etc. In an embodiment of the invention inert gas is readily available in sea vessel 100. For example, inert gas is oxygen deficient and is topped up into an open ullage space of the ballast tanks of sea vessel 100. This leaves no space for bacteria and pathogens to thrive on due to oxygen deficient nature of inert gas and hence makes ballast water exchange more eco-friendly.

[0072] Various embodiments of the invention provide methods and systems for managing ballast water in sea vessel 100. The invention provides a method for exchanging ballast water by using a pressure difference. The invention provides a method and system for efficiently exchanging ballast water such that quantity of ballast water in the ballast tanks of sea vessel 100 remains substantially unchanged. The invention also provides a method and system to carry out ballast water exchange without disturbing marine ecological balance. The invention further provides a method and system for filtration and treatment of ballast water to substantially eliminate, bacteria and pathogens from ballast water. The invention further provides method and system for treating ballast water with ozone gas and ultra violet radiation for reducing bacteria and pathogens present in ballast water. The invention also provides method and system for reducing maintenance cost of sea vessel 100 by decreasing ballast pump running hours. The invention further provides method and system for reducing extent of ballast water exchange needed in deep sea by minimizing bacteria and pathogens present in ballast water taken at a port. Therefore, instead of exchanging a ballast tank volume of 300% during ballast water exchange in deep sea, a ballast tank volume of only 100% is required to be exchanged in deep sea to achieve 95% exchange of ballast water in sea vessel 100.

[0073] Those skilled in the art will realize that the above recognized advantages and other advantages described herein are merely exemplary and are not meant to be a complete rendering of all of the advantages of the various embodiments of the present invention.

[0074] In the foregoing specification, specific embodiments of the present invention have been described. However, one of ordinary skill in the art appreciates that various modifications and changes can be made without departing from the scope of the present invention as set forth in the claims below. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of the present invention. The benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential features or elements of any or all the claims. The present invention is defined solely by the appended claims including any amendments made during the pendency of this application and all equivalents of those claims as issued.

Claims

CLAIMSWhat is claimed is:

1. A method for managing ballast water in a sea vessel, the method comprising: purifying ballast water in at least one ballast tank in shallow water; ballasting the at least one ballast tank in deep sea through an inlet corresponding to each ballast tank at a first pre-determined pressure level; and deballasting the at least one ballast tank simultaneous to ballasting the at least one ballast tank in deep sea through an outlet corresponding to each ballast tank at a second pre-determined pressure level.

2. The method of claim 1, wherein a ballast tank of the at least one ballast tank is one of a dedicated double bottom segregated ballast tank, other double bottom segregated ballast tank, a side segregated ballast tank, a fore peak ballast tank and an after peak ballast tank.

3. The method of claim 2, wherein a ballast tank of the at least one ballast tank is one of a side segregated ballast tank, other double bottom segregated ballast tank, a fore peak ballast tank and an after peak ballast tank, the ballasting comprises: filling ballast water in a ballast tank through a first sea chest into a sea chest ballast pipeline connected to the first sea chest; and pumping-in ballast water from the sea chest ballast pipeline into a filling pipeline fitted in at least one side segregated ballast tank, wherein the filling pipeline comprises an inlet corresponding to each side segregated ballast tank of the at least one side segregated ballast tank.

4. The method of claim 3, wherein ballasting further comprises: channeling ballast water from a side segregated ballast tank of the at least one side segregated ballast tank to at least one other double bottom segregated ballast tank through perforations at bottom of the side segregated ballast tank.

5. The method of claim 2, wherein a ballast tank of the at least one ballast tank is one of a side segregated ballast tank, other double bottom segregated ballast tank, a fore peak ballast tank and an after peak ballast tank, the deballasting comprises: discharging ballast water from a ballast tank by channeling ballast water from an outlet corresponding to the ballast tank through an intermediate ballast pipeline; and channeling ballast water from the intermediate ballast pipeline to a second sea chest.

6. The method of claim 5, wherein an outlet corresponding to a side segregated ballast tank of at least one side segregated ballast tank comprises at least one of one or more perforations at bottom of the side segregated ballast tank and a bellmouth opening in the side segregated ballast tank.

7. The method of claim 5, wherein deballasting is performed under gravity.

8. The method of claim 2, wherein a ballast tank of the at least one ballast tank is a dedicated double bottom segregated ballast tank, the ballasting comprises: filling ballast water in a ballast tank through a first sea chest into a sea chest ballast pipeline connected to the first sea chest, wherein the sea chest ballast pipeline comprises an inlet corresponding to the ballast tank.

9. The method of claim 8, wherein the inlet corresponding to the ballast tank comprises a T-shape connector connected to the sea chest ballast pipeline.

10. The method of claim 8, wherein ballasting is performed under gravity.

11. The method of claim 8, wherein deballasting comprises: discharging ballast water from the ballast tank by pumping-out ballast water from the ballast tank through an outlet corresponding to the ballast tank into an intermediate ballast pipeline; and channeling ballast water from the intermediate ballast pipeline to a second sea chest.

12. A method of purifying ballast water while filling ballast water in at least one ballast tank in a sea vessel in shallow water, the method comprising: passing ballast water across an overflow wall in the at least one ballast tank; and filtering ballast water through a filter wall in the at least one ballast tank.

13. The method of claim 12, wherein a ballast tank of the at least one ballast tank is a dedicated double bottom segregated ballast tank.

14. The method of claim 13, wherein ballast water is filled in at least one dedicated double bottom segregated ballast tank through a sea chest into a sea chest ballast pipeline connected to the sea chest, wherein the sea chest ballast pipeline comprises an inlet corresponding to a dedicated double bottom segregated ballast tank of the at least one dedicated double bottom segregated ballast tank.

15. The method of claim 14, wherein the inlet corresponding to the dedicated double bottom segregated ballast tank comprises a T-shape connector connected to the sea chest ballast pipeline.

16. The method of claim 15, wherein filling of the dedicated double bottom segregated ballast tank is performed under gravity.

17. The method of claim 12, wherein purifying further comprises treating ballast water with at least one of ozone and an ultra violet radiation.

18. The method of claim 12, wherein purifying further comprises filling an inert gas in an ullage space of the at least one ballast tank.

19. The method of claim 12 further comprising removing at least one contaminating matter accumulated due to purification of ballast water by using at least one baffle plate located on the overflow wall.

20. The method of claim 13, wherein purified ballast water is pumped from at least one dedicated double bottom segregated ballast tank to at least one of other double bottom segregated ballast tank, a side segregated ballast tank, an after peak ballast tank and a fore peak ballast tank.

21. A system for managing ballast water in a sea vessel, the system comprising: a purification assembly situated in at least one of at least one ballast tank and at least one ballast pipeline to purify ballast water; a filling ballast pipeline fitted in the at least one ballast tank to fill ballast water in the at least one ballast tank; a sea chest ballast pipeline connected to sea through at least one sea chest to fill and discharge ballast water from the at least one ballast tank; and an intermediate ballast pipeline connecting the filling pipeline and the sea chest ballast pipeline to fill and discharge ballast water from the at least one ballast tank.

22. The system of claim 21, wherein a ballast tank of the at least one ballast tank is one of a dedicated double bottom segregated ballast tank, other double bottom segregated ballast tank, a side segregated ballast tank, a fore peak ballast tank and an after peak ballast tank.

23. The system of claim 22 further comprising a connector connected to the sea chest ballast pipeline and having an inlet corresponding to at least one dedicated double bottom segregated ballast tank.

24. The system of claim 23, wherein the connector comprises a T-shape connector.

25. A system of purifying ballast water while filling ballast water in at least one ballast tank in a sea vessel in shallow water, the system comprising: an overflow wall located in the at least one ballast tank to arrest at least one contaminating matter in ballast water; and a filter wall located in the at least one ballast tank to filter ballast water.

26. The system of claim 25, wherein a ballast tank of the at least one ballast tank is one of a dedicated double bottom segregated ballast tank, other double bottom segregated ballast tank, a side segregated ballast tank, a fore peak ballast tank and an after peak ballast tank.

27. The system of claim 26, wherein at least one of the overflow wall and the filter wall is located on a transverse axis of at least one dedicated double bottom segregated ballast tank.

28. The system of claim 27, wherein the filter wall divides a dedicated double bottom segregated ballast tank of the at least one dedicated double bottom segregated ballast tank into a first compartment and a second compartment.

29. The system of claim 28, wherein ballast water is channeled from the first compartment to the second compartment through the filter wall.

30. The system of claim 25, wherein the filter wall comprises at least one of charcoal, pebbles, ceramics and a membrane.

31. The system of claim 27, wherein height of the overflow wall is less than height of a dedicated double bottom segregated ballast tank of the at least one dedicated double bottom segregated ballast tank.

32. The system of claim 26 further comprising at least one of an ozonation unit and an ultra violet radiation unit located in the at least one ballast tank and at least one ballast pipeline to treat ballast water.

33. The system of claim 26, wherein the overflow wall comprises at least one baffle plate to remove the at least one contaminating matter accumulated over time from at least one dedicated double bottom segregated ballast tank.