WO1989007069A1

WO1989007069A1 - Shallow water modular boom system

Info

Publication number: WO1989007069A1
Application number: PCT/AU1989/000043
Authority: WO
Inventors: Leo Graf
Original assignee: L. Graf & Co. Pty. Limited
Priority date: 1988-02-04
Filing date: 1989-02-03
Publication date: 1989-08-10

Abstract

A shallow water, modular boom system comprising a cylindrically-shaped oil-absorbing material (106) held in a wide mesh bag (107) which is secured to a skirt portion (109) of durable material carrying buoyancy means (101) and having attached thereto along a lower edge ballast means (102A) to enable the oil-absorbing material (106) to float on the surface of the water while the skirt portion (109) is kept substantially vertical in the water.

Description

SHALLOW WATER MODULAR BOOM SYSTEM TECHNICAL FIELD

This invention relates to a modular system for the erection of a boom for the containment of pollution on the surface of a body of water, such as pollution resulting from oil spills, and more particularly to a said modular system which is able to be used close inshore, for example in shallow water or beach environs.

BACKGROUND ART Containment of pollution on the surfaces of bodies of water is a constant problem, created especially by damaged vessels. If the pollution, particularly if it is oil, is not contained as early as possible it will sooner or later damage beaches and other coastal environs and cause other well-documented deleterious effects, such as the carnage wrought among sea-bird populations. Oil especially will gradually dissipate so as to cover a wide area of water, and in this regard an astounding quantity of oil is illegally discharged into the world's oceans from the washing-out of vessels' tanks.

A proved effective way of limiting this damage is to physically isolate the source of pollution - say, an oil slick or spill - by employing a boom or similar device. This is, of course, a well-known technique, and especially useful are modular systems which are able to be assembled, adjacent the source of pollution, to a size appropriate to the extent of the pollution.

Such a system is described, illustrated and claimed in the specification relating to Australian patent application no. 23331/86 which is co-pending.

However, the known modular systems generally suffer from the drawback of being non-effective or, at least, not fully effective, in very shallow waters close-in to beaches. This is because there is not usually sufficient depth of water to maintain the boom floating upright, that is to say, the freeboard portion will "flop over" into the water.

DISCLOSURE OF INVENTION

It is therefore an object of the present invention to overcome the above and other disadvantages by the provision of a modular boom system adapted for use in water too shallow to enable a conventional boom to float upright; the modular boom system comprising: a first component including a length of a durable material; at least one pocket for buoyancy material in the length of durable material; ballast means associated with a longitudinal edge of the said length; and, affixed to the length, at least one means for securing thereto a second component; said second component including at least one cylindrical length of an oil-absorbing material releasably securable to the first component by means of the or each securing means: whereby the effect of combined weight and buoyancy ensures that the at least one cylindrical length of oil-absorbing material is maintained in a position, when in use, such that oil on the surface of shallow water is able to be effectively taken up.

Preferably, the durable material is a length of double-thickness, PVC- or PVC/polyurethane-coated polyester webbing.

Ideally, the oil-absorbing material of the second component is a coherent, continuous-fibre material contained in one or more plastic mesh bags.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the reader may gain a better understanding of the present invention, hereinafter will be described a preferred embodiment thereof, by way of example only and with reference to the accompanying drawings in which:- Figure 1 is a fragmented side elevation of a first component according to the present invention; Figure 2 is a perspective view of assembled first and second components; and

Figure 3 is an end elevation.

Throughout the drawings, like integers are referenced by the same numeral.

BEST MODE OF CARRYING OUT THE INVENTION

The modular boom system according to the present invention comprises a first component, generally referenced JO and a second component, generally referenced 20. First component 10 includes a length of double-thickness, so-called "heavy-duty" fabric, ideally PVC-, or polyurethane PVC-coated polyester webbing material - advantageously in 10-metre lengths. At each end of component 10, and optionally at locations intermediate the ends, is a vertical pocket 101 adapted to contain a buoyancy material such as dense, sealed-cell polyethylene flotation material. Along the lower edge of the normally-depending skirt portion 109 of first component 10 there may well be a tunnel 102 through which a metal chain 102A - see Figure 3 - is able to extend to function as ballast to keep the component upright during assembly, or to ensure that depending skirt portion 109 drags along the beach bottom, represented at 110 in Figure 3, below the water surface, to ensure that surface oil on the water will not be able to seep under the boom; in Figures 1 and 3, the water-line is indicated by the symbol "W/L".

At appropriate linear intervals along the length of component 10 there is provided a securing means such as the straps 103 and associated buckles, clips, or the like, referenced 104. Component 10 may also be provided with flexible stays or battens 105 and all, or some, of these may have suitable mooring attachment points, or anchor points 105A; the purpose of these is to prevent the freeboard portion of the component from "flopping over" into the water during assembly.

Figures 2 and 3 show a first component 10 and a second component 20 assembled together by straps 103 and buckles etc. 104 to form part of the inventive shallow-water, modular boom system. Second component 20 includes a cylindrical length 106 of an oil-absorbing material which is releasably securing to the webbing of first component l _ by the said securing means 103, 104.

The length 106 of the second component ^"20 is advantageously 10 metres, to be in accord with the preferred 10-metre length of first component 10; they may be secured together by, say, nine equidistantly-spaced securing means 103, 104.

The preferred oil-absorbing material is that marketed under the name GRABOL, by Aust-Pol Engineering Pty. Limited (GRABOL is a Registered Trade Mark). This material is a coherent, continuous-fibre material - not a granulated material - ideally contained in wide-mesh "poly" bags, as indicated at 107; it is capable of extremely rapid oil absorption, absorbing approximately 20 times its own weight. Each second component 20 ideally has a diameter of about 150 mm and may readily be joined to an adjacent such by a filament 108, ideally a strap or rope which extends through the full length of the component to thus also provide a continuous strength-importing element.

As will be realised, in very shallow waters, close into beaches perhaps, skirt portion 109 will curl under the boom component 20, which in effect sits on the surface of the water. Ballast chain 102A_ in its tunnel 102 ensures that skirt portion 109 drags behind the floating part of the assembly, thus maintaining a barrier against oil seepage under the boom.

In a variation, the continuous 10-metre run of oil-absorbing materials may be replaced by a plurality of shorter cylindrical lengths each of perhaps 1 metre and about 150 mm in diameter. In a further variation, discrete, spaced-apart portions of buoyancy material may be used to support, at the water-line, a flexible tube or hose having multiple perforations and attached to pumping means, to act as a surface skimmer to remove oil from the surface of the water.

While the above description is in terms of a two-component modular boom system, it will be clear that the cylindrical, oil-absorbing components could well be employed alone and, in fact, by themselves are eminently suited for protection in or around areas of water or dry land where spillage of oil is likely to occur, or already has occurred. From the foregoing, it will be readily appreciated by those skilled in the art that numerous variations and modifications may be made to the invention without departing from the scope and spirit thereof as set out in the following claims.

Claims

1. A modular boom system adapted for use in water too shallow to enable a conventional boom to float upright; said modular boom system comprising: a first component including a length of a durable material; at least one pocket for buoyancy material in said length of durable material; ballast means associated with a longitudinal edge of the said length; and, affixed to the said length, at least one means for securing thereto a second component; said second component including at least one cylindrical length of an oil-absorbing material releasably securable to said first component by means of the or each said securing means: whereby the effect of combined weight and buoyancy ensures that the at least one cylindrical length of oil-absorbing material is maintained in a position, when in use, such that oil on the surface of shallow water is able to be effectively taken up.

2. The system as claimed in Claim 1, wherein said durable material is a length of double-thickness plastic-coated polyester webbing.

3. The system as claimed in Claim 1 or Claim 2, wherein said plastic-coated webbing is PVC-coated webbing.

4. The system as claimed in Claim 1, wherein said plastic-coated webbing is polyurethane/PVC-coated webbing.

5. The system as claimed in Claim 1 or Claim 2, wherein buoyancy material which the or each pocket is adapted to contain is a dense, sealed-cell polyethylene flotation material.

6. The system as claimed in Claim 1 or Claim 2, wherein said ballast means is a metal chain extending through a tunnel in the said longitudinal edge.

7. The system as claimed in Claim 1 or Claim 2, wherein the or each securing means comprises a strap and associated buckle or clip.

8. The system as claimed in Claim 1 or Claim 2, wherein the said length is further provided with at least one flexible stay or batten including a mooring attachment or anchor point at a lower end thereof.

9. The system as claimed in Claim 1 or Claim 2 , wherein said oil-absorbing material of said second component is a coherent, continuous-fibre material contained in one or more plastic mesh bags.

10. The system as claimed in Claim 1 or Claim 2, wherein the or each cylindrical length of said second component has, extending therethrough, a filament by means of which a said cylindrical length is able to be joined is series to another said cylindrical length.

11. The system as claimed in any one of the preceding claims further comprising a perforated tube or hose adapted to be supported at the water-line of said system and pumping means attachable to said perforated tube or hose.