Drain processing system for methanol fuel vessel

Abstract

To provide a drain processing system for a methanol fuel vessel capable of preventing outboard discharge of leaked methanol and reducing drain piping steel material etc.SOLUTION: A drain processing system for a methanol fuel vessel includes: a methanol tank 10 for fuel installed on an upper deck 2; a drip tray 20 installed over total lower periphery of the tank of the methanol tank 10; a primary retention tank 30 for retaining drain ejected from the drip tray 20; a methanol detector 40 for detecting methanol contained in the drain retained in the primary retention tank 30; and an inboard retention tank 50 for retaining the drain including methanol. When methanol is not detected by the methanol detector 40, the retained drain in the primary retention tank 30 is ejected outboard, and when methanol is detected by the methanol detector 40, the drain retained in the primary retention tank 30 is retained in the inboard retention tank 50.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a methanol-fueled ship, and more particularly to a drain treatment system for a methanol-fueled ship. [Background technology]

[0002] Traditionally, heavy oil has been the main fuel used on ships, but international treaties and other regulations have been tightening regarding emissions of nitrogen oxides, sulfur oxides, carbon dioxide, and other substances contained in exhaust gases.

[0003] In response to this, ships powered by methanol have been proposed as an environmentally friendly, clean fuel.

[0004] Patent Document 1 describes an invention relating to a ship for transporting methanol, in which methanol taken from a methanol storage tank is used as fuel for a diesel engine, and an invention relating to an electrically propulsed ship that uses hydrogen gas obtained by reforming methanol to generate electricity in a fuel cell.

[0005] Patent Document 2 describes an invention relating to a ship in which a methanol fuel tank 12 is arranged on the upper deck and supplies methanol to an internal combustion engine 11 . [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 10-167189 [Patent Document 2] JP 2015-221645 A Summary of the Invention [Problem to be solved by the invention]

[0007] When installing a methanol fuel tank on the upper deck, it is necessary to install drip trays around and under the tank to prevent methanol leakage. The ship 100 shown in Figure 2 has a methanol tank 10 installed on the upper deck 2 and a drip tray 20 installed around the entire periphery under the tank.

[0008] When the methanol tank 10 is installed in an exposed area such as on the upper deck 2, rainwater and the like may accumulate in the drip tray 20, so a drain line is provided to discharge the water overboard. However, in the event of a methanol leak, the methanol will be discharged overboard from the same drain line, so a separate drain line must be provided to store the leaked methanol onboard.

[0009] Figure 3 is a diagram showing the configuration of a drain treatment system for a methanol-fueled ship according to a conventional example, which has a drain line for discharging rainwater etc. outside the ship and a drain line for storing leaked methanol inside the ship, which are provided separately. Figure 3(a) is a plan view, and Figure 3(b) is a schematic diagram of the inside of the ship.

[0010] A drip tray 20 is installed around the entire bottom of the methanol tank 10, and an outlet 121 (for rainwater, etc.) and an outlet 122 (for methanol) are provided at each of the four corners. Each of the outlets 121, 122 is opened and closed by an opening and closing valve. Rainwater, etc. that has accumulated in the drip tray 20 is discharged from the outlet 121 through the drain line 109a to the outside of the ship. Meanwhile, methanol that has leaked into the drip tray 20 is stored in the onboard storage tank 150 through the drain line 109b from the outlet 122. The crew member determines whether the drainage that has accumulated in the drip tray 20 is rainwater, etc. or leaked methanol, and operates the opening and closing valve to flow to either of the drain lines.

[0011] However, because methanol is colorless and transparent, it is difficult to visually determine whether the drainage collected in the drip tray is rainwater or leaked methanol. Therefore, crew members must use portable gas detectors to make the determination, but because this is done during regular or special patrols, there is a possibility that the methanol leak may go unnoticed and be overlooked depending on the timing. In addition, the possibility of crew members misjudging whether it is rainwater or leaked methanol cannot be denied.

[0012] Furthermore, if a drain line for discharging rainwater, etc. outside the ship and a drain line for storing leaked methanol inside the ship are provided separately, costs will increase due to the increase in steel material for the drain piping, etc.

[0013] The present invention is devised to solve the above-mentioned problems of the conventional technology, and provides a drain treatment system for a methanol-fueled ship that can prevent leaked methanol from being discharged overboard and reduce the amount of steel material for drain piping, etc. [Means for solving the problem]

[0014] In order to solve the above problems, the drain treatment system for a methanol-fueled ship of the present invention comprises a methanol tank for fuel installed in an exposed area, a drip tray installed around or below the methanol tank, a primary storage tank for storing drain discharged from the drip tray, a methanol detector for detecting methanol contained in the drain stored in the primary storage tank, and an onboard storage tank for storing the drain containing methanol, and is characterized in that if the methanol detector does not detect methanol, the drain stored in the primary storage tank is discharged overboard, and if the methanol detector detects methanol, the drain stored in the primary storage tank is stored in the onboard storage tank.

[0015] It is also preferable that the system further comprises an overboard discharge valve provided in a drain line extending from the primary storage tank to the overboard storage tank, and an onboard storage valve provided in a drain line extending from the primary storage tank to the onboard storage tank, and when the methanol detector does not detect methanol, the overboard discharge valve is opened and the onboard storage valve is closed, and when the methanol detector detects methanol, the overboard discharge valve is closed and the onboard storage valve is opened. Effect of the Invention

[0016] The drainage treatment system for a methanol-fueled ship of the present invention comprises a methanol tank for fuel installed in an exposed area, a drip tray installed around or below the methanol tank, a primary storage tank for storing drainage discharged from the drip tray, a methanol detector for detecting methanol contained in the drainage stored in the primary storage tank, and an onboard storage tank for storing drainage containing methanol.Therefore, all drainage that accumulates in the drip tray is stored in the primary storage tank regardless of the presence or absence of methanol, where the presence or absence of methanol is determined by the methanol detector.

[0017] If the methanol detector does not detect methanol, the drain stored in the primary storage tank is discharged overboard, and if the methanol detector detects methanol, the drain stored in the primary storage tank is stored in the onboard storage tank. This eliminates the risk of crew members overlooking a methanol leak or making an incorrect judgment, and prevents leaked methanol from leaking overboard.

[0018] In addition, the drain line between the drip tray and the primary storage tank does not need to distinguish between rainwater, etc. and leaked methanol, which leads to a reduction in the amount of drain piping steel, etc.

[0019] In addition, if there is an overboard discharge valve installed on the drain line leading from the primary storage tank to the overboard storage tank, and an onboard storage valve installed on the drain line leading from the primary storage tank to the onboard storage tank, and if the methanol detector does not detect methanol, the overboard discharge valve is opened and the onboard storage valve is closed, and if the methanol detector detects methanol, the overboard discharge valve is closed and the onboard storage valve is opened, then by linking the methanol detector and the two valves, the overboard discharge of rainwater, etc. and the onboard storage of leaked methanol can be easily automated.

[0020] Thus, according to the present invention, it is possible to provide a drain treatment system for a methanol-fueled ship that can prevent leaked methanol from being discharged overboard and reduce the amount of drain piping steel material, etc. [Brief description of the drawings]

[0021] [Figure 1] FIG. 1 is a configuration diagram of a drain treatment system for a methanol-fueled ship according to an embodiment of the present invention. [Diagram 2] FIG. 1 is a diagram showing the layout of methanol tanks on a methanol-fueled ship. [Diagram 3] FIG. 1 is a configuration diagram of a drain treatment system for a methanol-fueled ship according to a conventional example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] A drain treatment system for a methanol-fueled ship according to an embodiment of the present invention will be described with reference to Figures 1 and 2. Methanol-fueled ships include cargo ships such as bulk carriers, container ships, and tankers, but are not limited to these.

[0023] 2 is a diagram showing the arrangement of methanol tanks in a methanol-fueled ship. An accommodation area 1 is located near the stern of the methanol-fueled ship 100. The upper deck of the methanol-fueled ship 100 is divided into an upper deck 2 located on the stern side of the accommodation area 1, and an upper deck 3 located on the bow side of the accommodation area 1.

[0024] Inside the hull below the accommodation area 1, there is an engine room 4, in which a main engine 5 is disposed. The power of the main engine 5 is transmitted to a propeller 6, providing the propulsion force for the methanol-fueled ship 100. A rudder 7 is disposed behind the propeller 6.

[0025] A methanol tank 10 for fueling the main engine 5 is installed on the upper deck 2 aft of the accommodation area 1. Methanol stored in the methanol tank 10 is supplied to the main engine 5 via piping 8. Note that control equipment and the like (not shown) are used to supply methanol. Also, the location of the methanol tank 10 is not limited to being aft of the accommodation area 1, but may be on the upper deck 3 on the bow side.

[0026] In this embodiment, the methanol tank 10 is installed on the upper deck, but this is not limited to this and may be installed in other locations that are exposed to wind, rain, and seawater, such as on the tower deck or on a deckhouse.

[0027] A drip tray 20 is installed around the entire bottom periphery of the methanol tank 10 to prevent leakage of methanol.

[0028] In this embodiment, the drip tray is installed around the entire bottom of the methanol tank 10, but this is not limited to this, and the drip tray may be installed around or around part of the bottom of the methanol tank 10.

[0029] FIG. 1 is a configuration diagram of a drain treatment system for a methanol fuel ship according to an embodiment of the present invention, where FIG. 1(a) is a plan view and FIG. 1(b) is a schematic diagram of the inside of the hull.

[0030] A drip tray 20 is installed around the entire bottom periphery of the methanol tank 10, and a drain outlet 21 is provided at each of the four corners. All of the drain outlets 21 are normally open, but are provided with plugs to prevent drainage during maintenance of valves, etc.

[0031] A drain line 9 is connected to each of the discharge ports 21, and the drainage collected in the drip tray 20 is stored in a primary storage tank 30 installed inside the hull 101 via the drain line 9 from the discharge port 21. The drainage collected in the drip tray 20 is not separated into rainwater or the like and leaked methanol, and is all led to the primary storage tank 30.

[0032] The primary storage tank 30 is a tank provided to store the drainage from the drip tray 20 and provide a gas layer, and the gas in the resulting gas layer is sucked up by the methanol detector 40 to detect the presence or absence of methanol gas.

[0033] The primary storage tank 30 is connected to a drain line 9a leading to the outside of the ship and a drain line 9b leading to an onboard storage tank 50. The onboard storage tank 50 is a tank for storing drainage containing methanol onboard, and the stored drainage containing methanol is periodically unloaded onto land. An overboard discharge valve 60 is provided on the drain line 9a, and an onboard storage valve 70 is provided on the drain line 9b.

[0034] The overboard discharge valve 60 and the onboard storage valve 70 may be pneumatically driven remote control valves, which are automatically controlled to be linked to the methanol detector 40. Specifically, when the methanol detector 40 does not detect methanol (normal operation), the overboard discharge valve 60 is controlled to be open and the onboard storage valve 70 is controlled to be closed. Then, the drain in the temporary storage tank 30 is discharged overboard via the drain line 9a.

[0035] On the other hand, when the methanol detector 40 detects methanol (methanol leakage), the overboard discharge valve 60 is controlled to close and the onboard storage valve 70 is controlled to open. Then, the drain in the temporary storage tank 30 is stored in the hull storage tank 50 via the drain line 9b.

[0036] The drain treatment system for a methanol-fueled ship in this embodiment comprises a methanol tank 10 for fuel installed on the upper deck 2, a drip tray 20 installed around the entire underside of the methanol tank 10, a primary storage tank 30 for storing drain discharged from the drip tray 20, a methanol detector 40 for detecting methanol contained in the drain stored in the primary storage tank 30, and an onboard storage tank 50 for storing drain containing methanol. Therefore, all drainage that accumulates in the drip tray 20 is stored in the primary storage tank 30 regardless of whether methanol is present or not, where the presence or absence of methanol is determined by the methanol detector 40.

[0037] If the methanol detector 40 does not detect methanol, the drain stored in the primary storage tank 30 is discharged overboard, and if the methanol detector 40 detects methanol, the drain stored in the primary storage tank 30 is stored in the onboard storage tank 50. This eliminates the risk of the crew overlooking a methanol leak or making an incorrect judgment, and prevents the leaked methanol from leaking overboard.

[0038] In addition, the drain line 9 between the drip tray 20 and the primary storage tank 30 does not need to distinguish between rainwater and leaked methanol, which leads to a reduction in drain piping steel materials, etc.

[0039] The system also has an overboard discharge valve 60 provided on the drain line 9a leading from the primary storage tank 30 to the outside of the ship, and an onboard storage valve 70 provided on the drain line 9b leading from the primary storage tank 30 to the onboard storage tank 50. When the methanol detector 40 does not detect methanol, the overboard discharge valve 60 is opened and the onboard storage valve 70 is closed. When the methanol detector 40 detects methanol, the overboard discharge valve 60 is closed and the onboard storage valve 70 is opened. Therefore, by linking the methanol detector 40 with the two valves 60, 70, the overboard discharge of rainwater, etc. and the onboard storage of leaked methanol can be easily automated.

[0040] In this way, the drain treatment system for a methanol-fueled ship according to this embodiment makes it possible to prevent leaked methanol from being discharged overboard and to reduce the amount of drain piping steel material, etc.

[0041] Although the drain treatment system for a methanol fuel ship according to the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various other modifications are possible.

[0042] For example, the methanol detector is configured to detect the presence or absence of methanol gas by sucking in the gas layer of the stored drain, but any other configuration may be used as long as it can detect methanol.

[0043] In addition, by linking the two valves with a methanol detector, the overboard discharge of rainwater, etc. and the onboard storage of leaked methanol are automated. However, the overboard discharge and onboard storage can also be switched manually depending on whether or not methanol is detected by the methanol detector. [Explanation of symbols]

[0044] 1 residential area 2 Upper Deck 3 Upper Deck 4. Engine Room 5 Main engine 6 Propellers 7. Rudder 8 Piping 9 Drain Line 10 Methanol Tank 20 Drip Tray 21 Outlet 30 Primary storage tank 40 Methanol Detector 50 Onboard storage tank 60 Overboard discharge valve 70 Hull storage valve 100 Methanol fuelled vessels 101 Hull 109 Drain Line 121 Outlet 122 Outlet 150 Onboard storage tank

Claims

1. The vessel comprises a methanol tank for fuel installed in the exposed area, a drip tray installed around and below the methanol tank, a primary storage tank for storing drainage discharged from the drip tray, a methanol detector for detecting methanol contained in the drainage stored in the primary storage tank, and an onboard storage tank for storing the drainage containing methanol; 1. A drain treatment system for a methanol-fueled ship, characterized in that when the methanol detector does not detect methanol, the drain stored in the primary storage tank is discharged overboard, and when the methanol detector detects methanol, the drain stored in the primary storage tank is stored in the onboard storage tank.

2. an overboard discharge valve provided in a drain line extending from the primary storage tank to the outside of the ship, and an onboard storage valve provided in a drain line extending from the primary storage tank to the onboard storage tank, 2. The drain treatment system for a methanol-fueled ship as described in claim 1, wherein when the methanol detector does not detect methanol, the overboard discharge valve is opened and the onboard storage valve is closed, and when the methanol detector detects methanol, the overboard discharge valve is closed and the onboard storage valve is opened.

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