WO2013162383A1

WO2013162383A1 - Apparatus for applying dispersant on oil slick from a boat

Info

Publication number: WO2013162383A1
Application number: PCT/NO2013/050076
Authority: WO
Inventors: Claus Rasmussen; Arne HOLUMSNES; Fredrik GATEVOLD; Baard Hoan
Original assignee: Jason Engineering As
Priority date: 2012-04-26
Filing date: 2013-04-26
Publication date: 2013-10-31
Also published as: NO20120486A1

Abstract

The application relates to an apparatus for applying a dispersant to an oil slick at sea from a boat, the apparatus comprising two support beams with associated nozzle manifolds, characterised in that the support beams are mounted inside a ship's hull and adapted to be passed out through a hatch or opening on each side of the hull, the apparatus having an inactive, retracted position when it is not in use, and an active, extended position when it is in use, and wherein the hatches or openings and the support beams with associated nozzle manifolds are arranged such that the dispersant, when the apparatus is in use, hits the sea/oil slick ahead of the breaking point of the boat's bow wave.

Description

Apparatus for applying dispersant on oil slick from a boat

The present invention relates to an apparatus for effective application of dispersants to oil slicks at sea. The apparatus is mounted permanently on board a boat, for example, on board a support vessel in connection with offshore oil installations.

Background

Dispersion is a known method for combating oil spills at sea. Attempts have previously been made to mount suspended, swinging spray booms of varying solutions, length and quality on the side of supply vessels and different support vessels. Studies/research conducted by, inter alia, SINTEF Materials and Chemistry in Trondheim has shown that these simple dispersion systems have a very limited effect, partly because the width of application has been too small, because the solutions have distributed the dispersant too unevenly, because the dispersant has been so atomised that it has been too easily caught by the wind and weather etc. All in all, the effect has been small in relation to the amount of dispersant used and the effort and time spent applying the dispersant.

Jason Engineering AS has, with chemical-technical advice from SINTEF, developed a system including two swinging support booms equipped with spray booms and associated manifold with nozzles. This system functions so much better than earlier solutions because it is mounted on the vessel such that the dispersing fluid is applied to and hits the oil film before the bow wave from the vessel hits, splits and disturbs the oil film on the sea surface. However, a prerequisite for this equipment to function is that the vessel on which it is mounted has an open deck at the front towards the bow in order to provide space in which to install and operate the equipment.

Many new support vessels that are under development, especially for Arctic areas, comprise an enclosed bow section (for example, the Ulstein X-Bow type ship and other similar designs). This means it is not possible to mount and operate the dispersion equipment manually on the foredeck of the vessel in such a way as to achieve optimal application of the dispersant. New and more stringent requirements relating to both HSE and oil leak handling equipment, are constantly being introduced, i.e., new vessels are increasingly required to be equipped with oil leak handling equipment, whilst HSE requirements are met. In addition, many of the new types of vessels with an enclosed bow section are often specially designed for Arctic conditions, which further increases the need and requirements for carefully thought-out and reliable systems. Moreover, there is a clear trend that vessels adapted for Arctic conditions comprise more automated equipment to protect the crew from the elements and the increased risk that exists when working on deck in Arctic conditions.

A challenge in connection with vessels having an enclosed bow section is that the available inside space is also limited. This also applies to some extent to traditional hull types, but the challenge seems to be even greater for vessels that have an enclosed bow section. As both the outside and inside space is already limited, it is very difficult to find space for additional equipment, especially equipment of some size.

Another challenge is that new requirements stipulate that oil leak handling equipment must be capable of being mobilised and be ready for use within 30 minutes.

In Arctic conditions, icing is a major problem. Icing affects the performance of the equipment and can, in some cases, put the equipment out of action or ruin it. In addition, icing makes it more difficult and dangerous for the crew to handle and stay in the vicinity of the equipment. Application of dispersant to oil slicks entails the use of fluids that can freeze to ice in Arctic conditions.

In connection with oil leak handling in the form of application of dispersants to an oil slick, it is desirable that neither more nor less dispersant be used than is necessary. It is not desired that the dispersant should become a source of pollution in itself, and in addition, as mentioned, the space on board a vessel is limited, and so it is desirable to use the dispersant in a prudent manner. If the oil leak handling equipment is incorrectly positioned or dimensioned, there is a risk that large volumes of dispersant will be wasted without achieving its intended purpose. Incorrect use can result in unnecessarily large amounts of dispersant being used to no effect, and in the dispersant being swept away by the elements and thus not hitting any oil slick, or in the dispersant being applied unevenly and thus not giving a uniform or optimal dispersing effect.

According to the present invention, at least some of these challenges are solved by means of an apparatus disclosed in claim 1. Other advantageous or alternative embodiments of the invention are disclosed in the dependent claims.

According to an aspect of the present invention, an apparatus is provided for applying dispersant to an oil slick at sea from a boat, the apparatus comprising two support beams for spray booms, later referred to as "nozzle manifolds", wherein support beams equipped with nozzle manifolds are mounted inside a ship's hull and are arranged to be passed out through two respective hatches or openings on each side of the hull, the apparatus having a passive, retracted position when it is not in use, and an active, extended position when it is in use, wherein a support beam with respective manifold and the hatches or openings are arranged such that the dispersant hits the oil slick ahead of the bow wave when the apparatus is in use, thereby ensuring that the dispersant strikes a water/oil surface that has not yet been affected by the vessel's waves, i.e., before the bow wave breaks and pushes the oil film away from the ship's side.

According to another aspect of the present invention, an apparatus is provided wherein the system comprises beams arranged to be pushed out and in of the hull, the beams being pushed by a mechanical or hydraulic mechanism, which mechanism may comprise drive via toothed rack, wire rope drive, cylinder and/or telescope.

According to a further aspect of the present invention, an apparatus is provided wherein each of the systems is provided with a nozzle manifold and nozzles, the nozzle manifold being adapted to be capable of being lowered and raised relative to the sea surface and the support beam from which it is suspended.

According to yet another aspect of the present invention, an apparatus is provided wherein the nozzle manifold is a twin manifold and comprises two rows of nozzles, the rows having different capacity, wherein the metering of dispersant onto an oil slick at sea can be adapted to alternate between or combine the capacity of the two rows. According to an advantageous embodiment of the present invention, an apparatus is provided wherein the nozzle manifold comprises heating cables for de-icing.

Technical description

According to one embodiment of the present invention, a specifically designed and strength- evaluated beam section 1 is used; see Figure 1. This section 1 is support beam/support arm for a nozzle manifold 6.

According to an advantageous embodiment of the present invention, the system comprises a twin nozzle manifold (not shown).

Support beam 1 is suspended from two bearing points 2 by, for example, a slide bearing of a synthetic material. The support beam 1 can be pushed/pulled back and forth. The two bearing points 2 are secured to a standard U-section 3 which forms the actual anchorage to a vessel's steel structure onto which it is preferably welded.

At one end of the support beam's 1 web are two pipes 4 with a quick release coupling at each end. These pipes are for the supply of dispersing fluid via hoses to the twin manifold 6.

On the other side of the beam is a mechanism 5 which pushes/pulls the support beam 1 back and forth along the bearing points 2. This mechanism 5 may comprises a toothed rack or wire rope driven system where the actual drive comprises a hydraulic or electric motor, or alternatively a mechanism including one or more hydraulic cylinders. Fig. 1 shows a system comprising a wire rope drive mechanism 5.

As mentioned in the introduction above, a first challenge that is encountered in connection with dispersion from vessels with an enclosed foreship is that it is not possible to position any such equipment on the outside of the hull. A second challenge is that there is limited space inside the hull forward towards the bow. The width of the boat may be of decisive importance for how far forward it is practically possible to position the equipment. There must be a compromise between what is ideal and what is practically possible. The bow wave, where and how it breaks, is of critical importance for whether the oil is hit with the dispersant or whether clean sea is sprayed to no avail.

It turns out in practice that the bow wave of a number of the new said vessels with enclosed foreship breaks far less and considerably further back than is the case with conventional boats with bulbous bow (depending on the boat's speed and the prevailing weather conditions). This is considered to be a major advantage as regards application of dispersant to an oil slick at sea with the aid of an apparatus according to the present invention.

As mentioned above and as shown in Figure 2, the nozzle manifolds 6 will have a certain distance a between each other when the apparatus according to the invention is in use, allowing a gap or area between the nozzle manifolds 6 on the starboard and port side to arise, which is not directly sprayed with dispersing fluid.

This gap or distance can, however, be minimised or eliminated by employing one or more of the following methods:

- the innermost nozzle or nozzles on the nozzle manifolds 6 can be adapted or arranged such that the spreading profiles of the dispersing fluid spray are as wide as possible and/or optionally directed inwards, whereby said gap or distance a, vertically, is as wide as the ship's hull at the waterline at the point where the apparatus according to the invention is arranged;

- the innermost nozzle or nozzles on the nozzle manifold 6 can be adapted or arranged such that the spreading profiles of the dispersant fluid spray are directed forwards and inwards, whereby said gap or distance is narrower than the hull at the waterline, at the point where the apparatus according to the invention is arranged,

- the support beams 1, and thus the nozzle manifolds 6, are pulled inwards, and thus together, when the nozzle manifolds 6 have been lowered to operational height. In the cases where the shape of the hull narrows closer to the waterline, the nozzle manifolds 6 can be drawn slightly inwards/together as shown by the arrow p in Figure 2.

As mentioned above, the system according to an advantageous embodiment may comprise a twin manifold 6, where the two rows of spray nozzles have different capacity (for example, 100% and 25% nominal capacity). By alternating between or combining the two rows of nozzles, it is possible to meter/apply an amount of dispersing fluid that is optimal in relation to the thickness and condition of the oil film. In addition to alternating between the two rows of nozzles, separately or together, the pressure in the manifolds can be varied steplessly, which in turn results in a stepless variable metering of dispersing fluid. In addition, the speed of the vessel can be adapted to the thickness and condition of the oil film in order to further optimise the application of the dispersant.

Fig. 1, which shows one embodiment of the present invention, shows that the nozzle manifold 6 can be hoisted up and down by means of two lines 10. Each line 10 runs via a pulley fastened to the support beam 1 and to a small hydraulically operated winch 7 that is remote-controlled from a radio control system or the like (not shown). Dispersing fluid is passed to the nozzle manifold 6 via hoses 9 which, for example, can be connected using rapid release couplings 8. At the inlet to the manifolds is a pressure-controlled shut-off valve. The task of this valve is to instantly shut off supply of fluid to the manifold 6 so that hoses 9 and pipes 4 do not run dry in the event of a break in the dispersion operation. This results in a precise starting and stopping of spray from the nozzles when the shut-off valve to the individual manifold is operated.

Supply of dispersing fluid from the storage tank(s) to the nozzle manifolds 6 can take place with the aid of a pump and a shut-off valve to each manifold. These valves can be equipped with a hydraulic actuator and with both a visual and an electrical indicator for open/closed position. Control of the valve may be effected manually, or, for example, by radio control.

The design, positioning and mounting of the equipment is such that all relevant HSE requirements are met. The part that is to be passed out through a special, adapted hatch in the ship's side is of an extremely slim form. It takes up very little space in height and width. There is free passage below (or above) during both operation and storage. Moving components that may cause personal injury are equipped with covers. All hydraulic and electric components are in accordance with relevant safety rules and requirements. No heavy components need be lifted. The heaviest component, the nozzle manifold, is hoisted up or down with the aid of rope and pulleys or two small winches with hand crank when it is to be stored or made ready for use. It is expedient to avoid conflict with other machines such as anchor capstan and mooring winches or other installations. Location and anchorage are up under the deck.

It is a requirement that the equipment should be mobilised and be ready for use within 30 minutes. When the equipment is stored and is so-called "stand by", the following steps only must be carried out for mobilisation: - switch on the main switch in the electric control cabinet

- fasten the radio control by belt around the waist

- hoist the manifold into place and connect lines

- run (using the radio control) the support arm and manifold halfway out through the hatch in the ship's side

- connect hoses (rapid release coupling) to the nozzle manifold

- run the support arm and manifold right out

- run manifold down to a suitable height above the sea surface.

It will be understood that the aforementioned procedure is relevant in the case that the apparatus according to the invention is controlled by a radio-controlled system. Other automatic control systems may also be used. A simpler/less costly, wholly or partly manual system may also be used within the scope of the present invention.

To prevent icing on the nozzle manifolds 6 and other exposed equipment as a result of sea spray and extreme cold, for example, during use in Arctic conditions, the nozzle manifolds 6, and optionally other exposed equipment, can be equipped with heating cable for de-icing. The heating cables can be connected via a plug and socket as required or controlled automatically by means of the control system.

Electrical equipment on the nozzle manifold 6 and other relevant equipment are in protection class EExe

The equipment is operated by hydraulic/electric means and can, as mentioned, be remote- controlled using radio control. In that case, the equipment can consist of two identical units mounted next to each other and used respectively on the starboard and port side of the vessel. They can be used independently of each other, but have a common system for remote control.

In, for example, the range 20-160% of nominal capacity, it is possible, according to one embodiment of the invention, to make stepless adjustment from the remote control. This is so as to aim for a maximally optimal dispersion when the oil film is of varying thickness. If the hydraulics generator fails, the block with shut-off valves can be connected to another hydraulic source via two valves and hoses. The control valves may also be operated manually if the control current (24VDC) is switched off. In the event of a lack of contact via radio, the operating panel can be connected to the control cabinet by mans of a flexible cable.

Figure 1 shows an embodiment of the apparatus according to the present invention, where:

1. Support beam

2. Slide bearing

3. Anchoring section

4. Pipe for supply of dispersant

5. Mechanism for reciprocating movement of the support beam

6. Nozzle manifold

7. Winches for hoisting the nozzle manifold up and down

8. Pressure-controlled shut-off valve

9. Hoses for supply of dispersant

10. Lines for hoisting manifold up and down

Figure 2 shows how a complete ship set consisting of two apparatus can be mounted on board a support vessel of a type similar to the Ulstein X-Bow, i.e., with enclosed bow section. Figure 2 shows a cross-section through the vessel immediately aft of the mooring and anchor winches. The apparatus is shown mounted under a deck ceiling. It will be understood that the apparatus can also be mounted on a deck. Figure 2 shows the support beams in their outermost position and the nozzle manifolds lowered down to about 4.5 m above the sea surface and with a spray of dispersant falling down on the sea surface.

Attached are also nine photographs of an embodiment of the present invention. These photographs show:

Photograph 1: The invention comprises a specifically designed and strength-evaluated beam section. This section is support arm for the nozzle manifold. Photograph 2: The beam section is suspended from two slide bearings of synthetic material. The beam section can be pushed/pulled back and forth.

Photograph 3: The two bearing points are secured to a standard U-section which forms the actual anchorage to the vessel's steel structure onto which it is preferably welded.

Photograph 4: On one side of the support beam web are two pipes with a rapid release coupling at either end. These pipes are for supply of dispersing fluid via hoses to the twin manifold.

Photograph 5: On the other side of the support beam is a mechanism which pushes/pulls the support beam back and forth. This mechanism may be a toothed rack or a wire, where the actual drive is a hydraulic or electric motor, or a mechanism having one or more hydraulic cylinders. Photograph 5 shows an apparatus with wire rope drive.

Photograph 6: As mentioned above, a twin manifold is included where a row of spray nozzles has different capacity (100% and 25% nominal capacity). By alternating between the two rows of nozzles, it is possible to meter/apply dispersing fluid on the basis of the thickness and condition of the oil film. In addition to alternating between the two rows of nozzles, separately or together, the pressure in the manifolds can be varied steplessly, which in turn results in a stepless variable metering of dispersing fluid.

Photograph 7: The manifold is hoisted up and down in that it is suspended from two lines. Each line runs via a pulley attached to the section and to a small hydraulically operated winch that is remote-controlled from the radio control.

Photograph 8: Dispersing fluid is passed to the nozzle manifold by means of hoses that are connected using rapid release couplings. At the inlet to the manifolds is a pressure-controlled shut-off valve. The task of this valve is to instantly shut off supply of fluid to the manifold such that hoses and pipes do not run dry in the event of a break in the dispersion operation. This results in a precise starting and stopping of spray from the nozzles when the shut-off valve to the individual manifold is operated. Photograph 9: The shut-off valve to each manifold is equipped with a hydraulic actuator and with both visual and electrical indicator for open/closed position. Control of the valve is from the radio control.

Claims

P a t e n t c l a i m s

1. An apparatus for applying a dispersant to an oil slick at sea from a boat, the

apparatus comprising two support beams with associated nozzle manifolds, c h a r a c t e r i s e d i n that the support beams are mounted inside a ship's hull and are adapted to be passed out through a hatch or opening on each side of the hull, the apparatus having an inactive, retracted position when it is not in use, and an active, extended position when it is in use, and wherein the hatches or openings and the support beams with associated nozzle manifolds are arranged such that the dispersant, when the apparatus is in use, hits the sea/oil slick ahead of the breaking point of the boat's bow wave.

2. An apparatus according to claim 1, wherein the support beams are adapted to be pushed out and in through the ship's hull essentially horizontally and essentially transverse to the longitudinal direction of the boat, the support beams being pushed by a mechanical or hydraulic mechanism, which mechanism comprising drive via toothed rack, wire rope drive, cylinder and/or telescope.

An apparatus according to claim 1 or 2, wherein each of the support beams is provided with a nozzle manifold and nozzles, the nozzle manifold being adapted to be capable of being lowered and raised relative to the sea surface and the support beam from which it is suspended.

An apparatus according to claim 3, wherein the nozzle manifold is a twin manifold and comprises two rows of nozzles, the rows having different capacity, wherein the metering of the dispersant onto an oil slick at sea can be adjusted by alternating between or combining the capacity of the two rows.

An apparatus according to claim 3, wherein the nozzle manifold comprises heating cables for de-icing.

6. An apparatus according to claim 3, wherein raising and lowering of the nozzle manifold is to be controlled from a wireless portable control panel (radio control).