US-12617517-B2 - System and method for fumigating a vessel with crew protection

US12617517B2US 12617517 B2US12617517 B2US 12617517B2US-12617517-B2

Abstract

A methods and systems of fumigating a vessel include delivering fumigant to a cargo area of the vessel. In particular, the vessel may be a roll-on/roll-off vessel. In such a system, an air pressure system is provided for maintaining a selected minimum pressure differential between a selected area of the vessel above the cargo area and the cargo area, such that pressure of the selected area is greater than the cargo area. A control system may maintain the pressure differential.

Inventors

Matthew Brian SLAVIN
Aric JANA

Assignees

Fintran Australia Pty Ltd

Dates

Publication Date: 20260505
Application Date: 20210526
Priority Date: 20200526

Claims (17)

1 . A control system for a roll-on/roll-off (RORO) vessel, the control system comprising a controller configured to: receive at least one pressure reading or at least one differential pressure reading from at least one of a selected area of the vessel or a cargo area during a fumigation; in response to the at least one reading, control an air delivery to the selected area of the vessel in order to maintain a selected minimum pressure differential between the selected area and the cargo area with a pressure of the selected area being greater than a pressure of the cargo area; and maintain the selected minimum pressure differential throughout the fumigation and a subsequent exhaust of a fumigant from the cargo area.
2 . The control system as claimed in claim 1 , wherein the selected minimum pressure differential is at least about 50 Pa, or between about 50 Pa and about 100 Pa.
3 . The control system as claimed in claim 1 , wherein the selected minimum pressure differential is pre-selected.
4 . The control system as claimed in claim 1 , wherein the control system is responsive to at least one of (i) one or more pressure sensors or (ii) differential pressure sensors, and is further configured to control one or more air supply fans to supply air to the selected area to maintain the selected minimum pressure differential.
5 . The control system as claimed in claim 4 , wherein the control system is configured to control at least a speed of the one or more fans via a variable speed drive.
6 . The control system as claimed in claim 1 , wherein the control system is configured to perform low range monitoring to detect at least one of (i) gaseous fumigant, (ii) carbon dioxide, (iii) carbon monoxide, or (iv) other volatile organic compounds (VOCs) at least one of (a) within the selected area or (b) at an air intake for a delivered air.
7 . A method of pre-configuring a control system which is ancillary to a roll-on/roll-off (RORO) vessel, the method comprising pre-configuring a controller of the ancillary control system such that the controller is configured to: receive at least one pressure reading or at least one differential pressure reading from at least one of a selected area of the vessel or a cargo area during a fumigation; in response to the at least one reading, control an air delivery to the selected area of the vessel in order to maintain a selected minimum pressure differential between the selected area and the cargo area with a pressure of the selected area being greater than a pressure of the cargo area; and maintain the selected minimum pressure differential throughout the fumigation and a subsequent exhaust of a fumigant from the cargo area.
8 . The method as claimed in claim 7 , further comprising preconfiguring the control system to maintain the selected minimum pressure differential of at least one of (i) at least about 50 Pa, or (ii) between about 50 Pa and about 100 Pa.
9 . The method as claimed in claim 8 , further comprising preconfiguring the control system to maintain or pre-select at least the selected minimum pressure differential.
10 . The method as claimed in claim 7 further comprising preconfiguring the ancillary control system to control one or more air supply fans to deliver the air to the selected area.
11 . The method as claimed in claim 7 , further comprising pre-configuring the control system or an additional ancillary control system to perform low-range monitoring to detect at least one of (i) gaseous fumigant, (ii) carbon dioxide, (iii) carbon monoxide, or (iv) other volatile organic compounds (VOCs) at least one of (a) within the selected area or (ii) at an air intake for the delivered air, wherein the controller is configured to control air delivery in response to an output of the low range monitoring.
12 . A system for fumigating a vessel wherein the system is ancillary to the vessel, the system comprising: a fumigant delivery system configured to deliver a fumigant to a cargo area of the vessel; and an air pressure system configured to maintain a selected minimum pressure differential between a selected area of the vessel above the cargo area and the cargo area, such that a pressure of the selected area is greater than a pressure of the cargo area.
13 . The system as claimed in claim 12 , wherein the vessel is a roll-on/roll-off vessel.
14 . The system as claimed in claim 12 , wherein the air pressure system comprises a controller configured to maintain the selected minimum pressure differential throughout a fumigation and an exhaust of the fumigant.
15 . The system as claimed in claim 12 , wherein an air intake for the air pressure system is remote from the one or more fumigant delivery sites and one or more exhaust sites.
16 . The system as claimed in claim 15 , wherein the air intake is more than about 30 metres from the one or more fumigant delivery sites and the one or more exhaust sites for an exhausted fumigant.
17 . The system as claimed in claim 15 , wherein the air intake is located quayside of the vessel, outwardly of a hull of the vessel, or at a forward end of the vessel.

Description

CROSS REFERENCE TO RELATED APPLICATION(S) This application relates to, and claims the benefit and priority from International Patent Application No. PCT/AU2021/050505 filed on May 26, 2021 that published as International Patent Publication No. WO 2021/237290 on Dec. 2, 2021, which claims the benefit and priority from Australian Patent Application No. 2020901707 and Australian Patent Application No. 2020901708, both filed on May 26, 2020, the entire disclosures of which are incorporated herein by reference. FIELD OF THE INVENTION The present invention relates to a system and method for fumigating a vessel. The invention has particular application to fumigation of roll-on/roll-off vessels. The present invention is also directed to a method of fumigating a roll-on/roll-off vessel. Furthermore, the invention relates to a temporary bulkhead. Although the present invention is directed to roll-on/roll-off vessels, certain aspects of the invention are by no means limited to these types of vessels and may have broader application to cargo vessels and other types of sea-faring vessels. The reader is also directed to our other coexisting application filed coincidentally: “System and method for fumigating a vessel with exhaust” concerning aspects of the present invention described herein but not claimed. The entire contents of that coexisting application are incorporated herein by reference. BACKGROUND It is a requirement in many jurisdictions that cargo onboard a cargo-carrying vessel be fumigated prior to unloading. Fumigation of an infested vessel may also be necessary. The fumigation process involves releasing fumigant into a cargo area of the vessel to eliminate, reduce, or avoid infestation of the cargo by insects or other undesirable pests. The fumigant may be provided in solid form and located in the cargo area, or may be provided in gaseous form and piped into the cargo area. The fumigation gases are usually toxic to human beings. The fumigation process may be conducted en-route, when anchored, or when moored at quay, and is typically conducted by specially trained personnel with specialised equipment. In most instances, members of the crew of the vessel will be located on the vessel during the fumigation process, and thus it is imperative that the fumigation process is conducted in such a manner that ensures that the crew (and the specially trained fumigation personnel) are not exposed to the toxic fumigant. Access to parts of the vessel such as the engine room and mooring lines may also be required during fumigation. A bulk carrier is a vessel specifically designed to transport unpackaged bulk cargo, such as grains, coal, ore, and other similar loose cargo. Bulk carriers typically comprise one or more separate cargo holds arranged fore to aft in the vessel. Grain or other unpackaged bulk goods may be loaded into and unloaded from the cargo holds by, for example, one or more cranes located on the deck of the vessel. Alternatively, conveyor loaders, shoreside cranes, or pneumatic loaders may be used to load and unload cargo. Each of the cargo holds typically also includes a hatch for closing the opening to the cargo holds. In bulk carriers, the accommodation area of the vessel and the engine room of the vessel are typically located aft of the cargo holds, with the accommodation area provided above the engine room. The cargo holds are separated from the engine room by a vertically extending bulkhead. The accommodation area is physically separated from the cargo holds, by being physically removed from the cargo holds by the intervening engine room and furthermore by two physical barriers including the vertically extending bulkhead and the deck between the engine room and the accommodation area. Due to this physical separation, it has generally been relatively safe to fumigate each of the cargo holds of a bulk carrier, subject to inspection of the vessel. A new challenge presents itself in safely fumigating roll-on/roll-off vessels, also known as RORO vessels. In vessels of this sort, the cargo area typically extends substantially the entire length of the vessel, and is arranged in decks within the vessel. The decks are interconnected by upright passageways such as staircases and ladders and the decks are joined by ramps. Further, the decks are grouped into watertight or gas tight zones, with typically 2 decks in each zone, although some vessels may include more than 2 decks per zone. Normally, RORO vessels are arranged into approximately 4 zones and each zone is independently ventilated. The cargo area is configured in this way so that breakbulk cargo such as wheeled cargo can be rolled onto or driven into the cargo area. In a RORO vessel, the accommodation area is typically located upon the weather deck of the vessel, with only plate steel and a floor covering separating the accommodation area from the uppermost deck of the cargo area. Thus, any openings or small cracks within this plate steel structure could r