OIL SLICK SAMPLING APPARATUS AND ...
Referring now to the drawings and, more particu
BACKGROUND OF THE INVENTION 5 ]arly, to FIG. 1, the sampling apparatus comprises a
Each year a large number of accidental oil discharges substantially annular frame or tube generally depicted occur in navigable waters, some of which are reported at 10. Frame ,10 is adapted to float on water and, acta the appropriate authorities, others are not. These cordingly, is fabricated of any suitable material which unreported oil discharges generally remain undetected will permit floatation such as, for example, polyethyuntil the appropriate authorities, as a part of anti-pollu- 10 lene. Since the frame may be hollow, other heavier tion patrols, locate the discharge or oil slick. Various materials are contemplated as long as the effective laboratory techniques are then used to identify charac- specific gravity thereof is less than that of water and teristic constituents of oil slick samples in an attempt to greater than that of the oil slick. Frame 10 has substanlocate the potential sources of the unreported oil dis- tially continuous exterior inner walls or surfaces 12 and charge. 15 outer exterior surfaces 14 and may be hollow for floa
A key element in the identification process is the tion and/or oil collection, as will become apparent
collection of an adequate sample of the oil slick. Exist- hereinbelow.
ing methods and apparatus for collection are crude and ^ oil slick floating on the water within the area
inefficient and ill suited for deployment from helicop- „A circumscribed or bounded by inner surfaces 12 is in
ters or other aircraft. Moreover, the problem of sample 20 fluid communication with the hollow interior chamber
contamination is ever present in the collection, han- }6 of *e frame 10 by means of one or more ports 18 ,
dling and delivery of the oil slick sample to the labora- located on a portion of inner surfaces 12. The portions
tory for analysis °^ surfaces 12 which are remote or diametrically opposed from ports 18 are wiped or coated with a thin
THE PRESENT INVENTION 25 layer of a suitable surface, active agent or surfactant
The foregoing problems are overcome according to schematically depicted at 20 in FIG. la. It is significant
the teachings of the present invention which provides a to,note that *e s"rfactant 20 is in contact with he
substantially annular or other suitably shaped member o,l-water interface I. To this end, the buoyancy of the
having inner and outer surfaces forming closed bound- 30 fr£T 10 f adJu,s^ such that rtfloats on the water with
„ A „a ♦ A ♦ n * „ „♦ „ -f 3U inner surfaces 12 being of sufficient depth to contact
anes and adapted to float on water, at least a portion of ., .. .. 6 .
., . _/ ... , . '. , r. , ... the oil as well as the water. , ...!...
the inner surface of the member is wiped or coated with . .. TM.s , u j -' * »i. c
.... .. . ■ , ,r o . ., , In the operation of the FIG. 1 embodiment, the frame
a suitable surface active material (surfactant) which , v , , , e _ . .. . , . .„ . .
- ^ , .: J/ ^ 10 may be deployed from a helicopter (not illustrated)
functions upon contact with water to spread from he fato ^ ... ^ of the oilFsUck As soon - the
inner surface of the member to thereby compress the 35 surfactant ^ inner surfaces J2 contacts the wateroil shck mto a very small tluckened area. oil interfac in a weU known manner, the interfacial
According to one embodiment of.the present inven- tension or free energ between ^ ^ and water is tion the member is hollow and contains one or more modified by the action of the surfactant, which, in turn openings through which the oil slick is driven and col- its the surfactant to spread in the direction of
lected by the spreading action of the surfactant. 40 arrows A in FIG. 1 causing the oil to recede and
According to a second embodiment of the present thicken towards a predetermined' area within the invention the inner surface of the member is impervi- boundaries of the frame 10. In this embodiment such ous and is substantially completely coated with the area is ^ vicinity of tne ports 18 which permit the oil surfactant whereby the oil slick is driven to a central to be coHected interiorly of the hollow frame 10 for area within the boundaries of said member and is col- 45 further analysis. In other words/the spreading action of lected by absorbtion or adsorption to a suitable collec- the surfactant drives the oil layer into the hollow of tion element located in said central area. frame 10 through ports 18.
The amount of the surfactant employed is so small As the oil enters the frame, the weight of the frame that its weight is undetectable and spreads in monomo- increases and it floats deeper in the water but since the lecular thickness on the order of 10"7 inches whereby 50 oil slick has been substantially thickened by the spreadno interference with or contamination of the oil slick is jng surfactant, the ports still collect mostly oil. possible so as to obscure the analysis thereof with re- As is well known to those skilled in this art many spect to composition, source or age. types of surfactant materials may be employed such as,
BRIEF DESCRIPTION OF THE DRAWINGS « ^. monooleate oleyl alcohol oleic
55 acid, Herder (Shell Oil Co. Trademark) and others.
For a fuller understanding of the present invention, Although not essential to operation of the present in
reference should now be had to the following detailed vention, it is preferred that the surfactant have a sur
description thereof taken in conjunction with the ac- face tension depression or surface pressure greater
companying drawings, wherein: than 30 dynes per centimeter.
FIG. 1 is a pictorial illustration of one embodiment 60 Although the frame 10 has been illustrated as circu
according to the present invention, lar or annular, other geometric shapes are contem
FIG. la is a section along line 1A—1A of FIG. 1, plated so long as the inner surfaces thereof are substan
FIG. 2 is a pictorial illustration of a slight variation of tially continuous to define a closed boundary for the
the embodiment of FIG,. 1, water and oil slick. Thus, FIG. 2 illustrates a rectangu
FIG. 3 is a pictorial illustration of a second embodi- 65 larly shaped frame 10' comprised of pipe lengths and
ment according to the present invention, and connecting elbows.
FIG. 4 is a view similar to FIG. 3 illustrating one Whereas the embodiments of FIG. 1 and FIG. 2 contechnique for removal of the oil slick. template the oil slick collection through ports leading