GB2229936A

GB2229936A - Pollution Control

Info

Publication number: GB2229936A
Application number: GB9007400A
Authority: GB
Inventors: John Tudor Morris
Original assignee: MANOR REFRACTORIES Ltd
Current assignee: MANOR REFRACTORIES Ltd
Priority date: 1989-04-01
Filing date: 1990-04-02
Publication date: 1990-10-10
Also published as: GB8907417D0; GB9007400D0

Abstract

Oil spillages on water are removed by plastics mesh which is preferentially wetted by the oil, which is subsequently removed by shaking or squeezing. Pieces or bundles of mesh may be dropped into the water and agitated therewith, or the mesh is in the form of an endless rope 20 which is dragged through the water or a boom which surrounds the oil slick. Mesh of the sort used for reinforcing concrete, whose resilience tends to close the openings, is preferred. Mesh may be polypropylene and coated with wetting agent. <IMAGE>

Description

Title: Pollution Control DESCRIPTION This invention concerns- pollution control and in particular concerns a method of dealing with oil spillages on water.

The problem of oil pollution of water is increasing and methods for dealing with such pollution are largely unsatisfactory. One obvious method of removing oil spills is to burn the oil but that can be hazardous. Another method is to disperse the oil using detergents but often the detergents used are almost as harmful to the environment and wildlife as the oil in itself.

Clearly it would be useful to have a means of separating oil from water so that the oil can be saved but coping with large scale oil spillages presents difficulties in producing equipment that can cope with such.

An object of this invention is to provide a method whereby oil may be separated from water.

It has now been surprisingly found that certain plastics materials in certain forms have an affinity for oil so that the oil attaches or adheres to the plastics material in preference to water.

Accordingly the present invention provides a method of separating oil from water comprising adding to a mixture of oil and water plastics materials that complies with one or more of the following categories: 1. plastics material which is hydrocarbon based, such as polypropylene or polyethylene; 2. plastics material in multistrand form such as in a mesh form preferably in a compressed mesh form possibly in discrete lengths or possibly in strands in a tangled form; 3. plastics material coated with one or more wetting agents, removing the plastics material from the water and separating from the plastics material oil attached or adhered thereto.

It has been found that plastics material in compressed mesh form such as used for reinforcing concrete is particularly suitable for use in the method of the present invention when provided in lengths of about 0.04m, although it is probable that the length of the plastics material will not be significant towards its efficacy. Indeed, it may be feasible to provide the plastics material in the form of a rope which can be dragged through an oil slick to pick up oil, the rope being taken into a vessel for the removal of oil therefrom and returned to the oil slick.

Alternatively, the rope may be used as a boom to surround and control an oil spillage whilst providing take up of oil.

In another preferred embodiment, the plastics material suggested herein may be dropped into an oil spillage in bundles or bales to be picked up after a period of time for removal of oil therefrom.

Oil removal from the plastics material may be by any suitable means, such as shaking or squeezing, after which the plastics material may be re-used.

For the method of the invention to operate effectively, it may be necessary for the plastics material to be agitated in the oil/water mixture. For use on oil spillages on the sea, it is likely, however, that tidal action/wave movement will provide the necessary agitation. For oil spillages on rivers or lakes, additional agitation may be required.

The invention will now be further described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows plastics material in compressed mesh form; Figure 2 shows the plastics material of Figure 1 opened out; Figure 3 shows schematically a first use of the plastics material of Figures 1 and 2; Figure 4 shows schematically a second use of the plastics material of Figures 1 and 2; and Figure 5 shows schematically a third use of the plastics material of Figures 1 and 2.

Referring to Figures 1 and 2 of the accompanying drawings, polypropylene coated with wetting agent is formed as a continuous mesh 10, which is normally in a relatively compressed form due to the resilience of the material and the manner of its manufacture. The mesh is believed to be produced in a single piece. When the plastics material is opened out (Figure 2) the mesh formation can be clearly seen.

Turning to Figure 3, lengths of the plastics material 10 of Figure 1 are dropped into an oil 12 and water 14 mixture. The mixture is agitated and the oil adheres to the plastics material. The plastics material is then removed leaving substantially oil free water behind. The oil on the plastics material can then be removed by shaking or squeezing thereof so that the plastics material can be reused.

In Figure 4 a rope 20 of compressed mesh polypropylene of the type shown in Figures 1 and 2 is dragged through an oil 22 water 24 mixture from a boat 26 and the rope passed through rollers 28 to remove oil adhered thereto.

In Figure 5 the rope 20 is shown used as a boom 30 to surround and control an oil spillage 32 whilst taking up oil from the water. Again rollers may be used to separate the oil from the rope.

Whilst the present invention has been described in connection with a particular type of mesh formation, it will be appreciated that other factors may be relevant in determining whether or not a particular plastics material or form thereof may be suitable for use in the method of the invention.

Claims

1. A method of separating oil from water comprising adding to a mixture of oil and water plastics material having an affinity for oil, removing the plastics material from the water and separating from the plastics material oil attached or adhered thereto.

2. A method as claimed in claim 1, wherein the plastics material is hydrocarbon based.

3. A method as claimed in claim 2, wherein the plastics material comprises polyethylene or polypropylene.

4. A method as claimed in claim 1, 2 or 3, wherein the plastics material is in multistrand form.

5. A method as claimed in claim 4, wherein the plastics material is in mesh form.

6. A method as claimed in claim 5, wherein the plastics material is in compressed mesh form.

7. A method as claimed in claim 4, 5 or 6, wherein the plastics material is provided in discrete lengths.

8. A method as claimed in claim 7, wherein said discrete lengths are about 0.04m.

9. A method as claimed in claim 4, 5 or 6, wherein the plastics material is provided in strands in a tangled form.

10. A method as claimed in any one of claims 1 to 8, wherein the plastics material is coated with one or more wetting agents.

11. A method as claimed in any one of claims 1 to 10, wherein the plastics material is in the form of a rope.

12. A method as claimed in claim 11, wherein the rope is dragged through the oil and water mixture.

13. A method as claimed in claim 11, wherein the rope is used as a boom to surround and control an oil spillage.

14. A method as claimed in any one of claims 1 to 10, wherein the plastics material is added to the oil/water in bundles or bales.

15. A method as claimed in any one of claims 1 to 14, wherein oil separation from the plastics material is by shaking or squeezing thereof.

16. A method as claimed in any one of claims 1 to 15 further comprising the step of agitating the oil and water mixture.

17. A method of separating oil from water substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.