U.S. patent application number 14/771597 was filed with the patent office on 2016-01-21 for floating barrier.
This patent application is currently assigned to DESMI RO-CLEAN A/S. The applicant listed for this patent is Thomas Aagaard Christensen, Hans Henrik Jensen, Steen Jensen, Lars Boldt Rasmussen. Invention is credited to Thomas Aagaard Christensen, Hans Henrik Jensen, Steen Jensen, Lars Boldt Rasmussen.
Application Number | 20160017559 14/771597 |
Document ID | / |
Family ID | 46757369 |
Filed Date | 2016-01-21 |
United States Patent
Application |
20160017559 |
Kind Code |
A1 |
Rasmussen; Lars Boldt ; et
al. |
January 21, 2016 |
FLOATING BARRIER
Abstract
The invention concerns one or more floating barriers for use
together with a conventional floating barrier for use in collecting
oil on a water surface. The floating barriers are of the kind where
the submerged part is partially penetrable for water and oil,
thereby providing an impeding but not blocking effect on a passing
flow of water. The function of the floating barriers is based on
the fact that by disposition upstream relative to the conventional
floating barrier and together with the latter they will constitute
a total system which can be moved through an oil-contaminated body
of water with substantially greater speed than a conventional
floating barrier, without leaking oil behind the floating barrier
system. The invention particularly concerns conditions of the
geometry, spacing and draught of the water-penetrable liquid
barriers.
Inventors: |
Rasmussen; Lars Boldt;
(Otterup, DK) ; Jensen; Steen; (Marslev, DK)
; Christensen; Thomas Aagaard; ( rslev, DK) ;
Jensen; Hans Henrik; (Odense S, DK) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Rasmussen; Lars Boldt
Jensen; Steen
Christensen; Thomas Aagaard
Jensen; Hans Henrik |
Otterup
Marslev
rslev
Odense S |
|
DK
DK
DK
DK |
|
|
Assignee: |
DESMI RO-CLEAN A/S
Odense S
DK
|
Family ID: |
46757369 |
Appl. No.: |
14/771597 |
Filed: |
March 1, 2012 |
PCT Filed: |
March 1, 2012 |
PCT NO: |
PCT/DK2012/050066 |
371 Date: |
August 31, 2015 |
Current U.S.
Class: |
405/63 |
Current CPC
Class: |
E02B 15/0864 20130101;
E02B 15/0842 20130101; E02B 15/045 20130101; E02B 15/0885 20130101;
E02B 15/0807 20130101; Y02A 20/204 20180101; E02B 15/06 20130101;
E02B 15/0814 20130101 |
International
Class: |
E02B 15/04 20060101
E02B015/04; E02B 15/06 20060101 E02B015/06 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 1, 2011 |
DK |
PA2011 00139 |
Claims
1. A floating barrier system including a conventional floating
barrier and at least two liquid-penetrable auxiliary barriers,
where the at least two liquid-penetrable auxiliary barriers are
arranged in front of a conventional floating barrier, and where the
liquid-penetrating effect is achieved by a given degree of
perforation, wherein the conventional liquid barrier as well as the
at least two liquid-penetrable floating barriers extend over a
horizontal length from one end to another end at a vertical depth
from an upper edge to an lower edge, wherein at least one of the at
least two liquid-penetrable auxiliary barriers are made with a
degree of perforation which is different from at least one other
liquid-penetrable auxiliary barrier.
2. A floating barrier system according to claim 1, wherein the
liquid-penetrable system is arranged with a front/first
liquid-penetrable auxiliary barrier with a first degree of
perforation, and at least with one other liquid-penetrable
auxiliary barrier with a second degree of perforation, wherein the
front liquid-penetrable auxiliary barrier is provided with a
greater degree of perforation than a subsequent liquid-penetrable
auxiliary barrier.
3. A floating barrier system according to claim 1, wherein the
degree of perforation of a liquid-penetrable auxiliary barrier is
substantially uniform in its full horizontal length.
4. A floating barrier system according to claim 1, wherein the
degree of perforation of a liquid-penetrable auxiliary barrier
varies over the horizontal length.
5. A floating barrier system according to claim 1, wherein the
individual liquid-penetrable floating barriers have different
vertical depths.
6. A floating barrier system according to claim 5, wherein the
front/first liquid-penetrable floating barrier is provided with a
greater depth than a subsequent liquid-penetrable floating
barrier.
7. A floating barrier system according to claim 5, wherein the
front/first liquid-penetrable floating barrier is provided with a
lesser depth than a subsequent liquid-penetrable floating
barrier.
8. A floating barrier system according to claim 1, wherein at least
one liquid-penetrable floating barrier includes one or more
vertical crossbars extending from the upper edge of the at least
one liquid-penetrable floating barrier towards its lower edge.
9. A floating barrier system according to claim 1, wherein the
spacing between the individual auxiliary barriers is made such that
the spacing (b) is between 80 and 150% of the spacing (c), and that
the spacing (a) is between 80 and 150% of the spacing (b).
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention concerns a floating barrier system
including a conventional floating barrier and at least two
liquid-penetrable auxiliary barriers, where the at least two
liquid-penetrable auxiliary barriers are arranged in front of a
conventional floating barrier, and where the liquid-penetrating
effect is achieved by a given degree of perforation, wherein the
conventional liquid barrier as well as the at least two
liquid-penetrable floating barriers extend over a horizontal length
from a first end to a second end at a vertical depth from an upper
edge to an lower edge.
[0003] 2. Description of Related Art
[0004] By prior art conventional floating barriers, the submerged
part is typically constituted by an approximately vertical
impenetrable wall which will block a given liquid flow that may try
to pass it. As the liquid flow is also prevented from passing over
the submerged part due to the overwater part, which is typically
constituted by buoyant bodies, the liquid flow is forced to pass
under the submerged part. This entails a local increase in speed of
the water flow which is to pass under the submerged part. This
means that a conventional floating barrier which is moved through a
liquid flow at e.g. 0.5 m/s locally can have liquid flows around
the submerged part, particularly in a zone in front of the floating
barrier (head wave effect), with double or triple speed. This
occurs in particular in a zone upstream in relation to the floating
barrier and in a area where a possible oil contamination can be
located. By exceeding about 1 m/s in difference of the speed in the
boundary layer between the oil layer and the water flow,
entrainment of oil drops will begin, the drops being moved under
the submerged part of the conventional floating barrier which
hereby is provided a leakage. By increased difference in speed,
this effect will be increased and large amounts of oil will be
entrained down under the floating barrier. For many years, this
phenomenon has been known as the limiting element in the use of
floating barriers which has caused the used towing vessels to be
limited in manoeuvring and the oil collecting operation to be very
time-consuming as well.
[0005] Use of supplementary, partially penetrable floating barriers
in order to counteract the above limitations to the efficiency of
floating barriers has been described and tested in the period
1990-1999 by various research groups. By these tests it has
appeared that it is possible to increase the operational speed by a
factor 2-3, but by using the present invention this factor is
increased to more than 4.
[0006] U.S. Pat. No. 3,771,662 discloses a solution where a
plurality of successive floating barriers are applied where the
rearmost floating barrier is a traditional floating barrier and
where at the upper edge of two floating barriers in front are
arranged a series of uniform apertures. Water and oil flow from the
surface through these uniform openings when the floating barrier is
towed through the water. These are very solid floating barriers
which only can be moved at a low speed in order not to form a
so-called head wave effect where water and oil are forced to speed
up so to say and to be entrained in a flow under the floating
barriers.
[0007] In order to avoid the inexpedient effect of head wave and
oil escaping the floating barrier, a bottom is arranged in U.S.
Pat. No. 3,771,662 between two floating barriers such that in
principle a basin is formed between the latter. This bottom is
arranged at an angle with horizontal such that the depth increases
towards the rearmost of the two floating barriers in question. All
water is thus to flow through a relatively small number of
apertures in the floating barrier at its upper edge and out of the
mentioned basin through a number of apertures at the bottom of it
and close to the rearmost of the floating barriers in question.
Thus it is the area of the mentioned apertures that determine how
fast the floating barrier can be moved and still be usable for
efficient collection.
[0008] U.S. Pat. No. 3,771,662 indicates a solution with large
resistance when drawn through the water and which only will have a
collecting effect at a very low speed, which obviously means that
this is a less efficient solution which does not live up to the
present demands to a rapid and efficient solution which in that
case can prevent a natural catastrophe by rapid collection of
spilled oil.
SUMMARY OF THE INVENTION
[0009] It is the purpose of the invention to indicate a floating
barrier system where the above mentioned drawbacks are counteracted
and where it is possible to perform collection of e.g. oil from a
water surface at a speed which is preferably about 300 to 400%
greater than hitherto.
[0010] As mentioned in the introduction, the invention concerns one
or more floating barriers for use together with a conventional
floating barrier for use in collecting oil on a water surface. The
floating barriers are of the kind where the submerged part is
partially penetrable for water and oil, thereby providing an
impeding but not blocking effect on a passing flow of water. The
function of the floating barriers is based on the fact that by
disposition upstream relative to the conventional floating barrier
and together with the latter they will constitute a total system
which can be moved through an oil-contaminated body of water with
substantially greater speed than a conventional floating barrier,
without leaking oil behind the floating barrier system. The
invention particularly concerns conditions of the geometry, spacing
and draught of the water-penetrable liquid barriers. The new
feature of a floating barrier system according to the invention as
indicated in claim 1 is that at least one of the at least two
liquid-penetrable auxiliary barriers is made with a degree of
perforation which is different from at least one other
liquid-penetrable auxiliary barrier. Hereby is achieved a graduated
retardation of the water whereby an appreciably increased speed can
be applied during towing of the floating barrier system by
collection of spilled oil.
[0011] In a preferred variant of a floating barrier system
according to the invention, the floating barrier system is arranged
with a front/first liquid-penetrable auxiliary barrier with a first
degree of perforation, and at least with one other
liquid-penetrable auxiliary barrier with a second degree of
perforation, wherein the front liquid-penetrable auxiliary barrier
is provided with a greater degree of perforation than a subsequent
liquid-penetrable auxiliary barrier. Hereby is introduced a
graduated degree of penetrability between two or more floating
barriers (auxiliary barriers) disposed upstream. However, this is
so that the floating barrier encountering the liquid flow first has
the greatest penetrability and thereby the lowest blocking action,
the next slightly lower penetrability and possibly a third with
even lower penetrability. This means that a passing liquid flow is
gradually decelerated, thus encountering the conventional blocking
floating barrier at a speed which does not give any problems with
regard to entrainment of oil and thereby leakage in the system. At
the same time, the graduated retardation effect means that none of
the penetrable auxiliary barriers will encounter the liquid flow at
a critical speed relative to the "head wave" effect.
[0012] In an embodiment of the invention, a floating barrier system
will be adapted such that that the degree of perforation of a
liquid-penetrable auxiliary barrier is substantially uniform in its
full horizontal length.
[0013] In another embodiment of the invention, a floating barrier
system may be adapted such that that the degree of perforation of a
liquid-penetrable auxiliary barrier varies over its horizontal
length. By this variant of the invention is avoided that the effect
of an unavoidable angling relative to the direction of flow is
avoided. It is thus possible to adapt the size of the perforations
of the auxiliary barrier such that the projected area facing in the
direction of movement is more or less uniform irrespective of the
auxiliary barrier having a U-shape, as it appears from the
subsequent Figures.
[0014] In another embodiment of this embodiment, graduation of the
draught of upstream disposed penetrable floating barriers forms a
part. A floating barrier system according to the invention can be
arranged such that the individual liquid-penetrable floating
barriers have different vertical depth and where the front/first
liquid-penetrable floating barrier is provided with the greatest
depth. However, it may also be so that the front/first
liquid-penetrable floating barrier has the lesser depth and that a
subsequent liquid-penetrable floating barrier is provided with the
greater depth. This will also entail a desirable graduated
deceleration of the liquid flow.
[0015] In yet a preferred embodiment of this invention, at least
one liquid-penetrable floating barrier may include one or more
vertical crossbars extending from the upper edge of the at least
one liquid-penetrable floating barrier towards its lower edge. The
vertical crossbar or crossbars is/are disposed with suitable
spacing with the object of ensuring vertical straightness of the
auxiliary barriers in the liquid flow. This means that the
penetrability of the auxiliary barriers is kept constant in
vertical direction without needing graduation of the
perforation.
[0016] Finally, the invention includes a characterisation of the
mutual spacing of the constituent penetrable floating barriers and
the distance to the blocking conventional floating barrier behind.
A preferred embodiment of a floating barrier system according to
the invention can be adapted such that the spacing between the
individual auxiliary barriers is made such that the spacing (b) is
between 80 and 150% of the spacing (c), and that the spacing (a) is
between 80 and 150% of the spacing (b).
[0017] The invention is explained in more detail in the following
with reference to the drawings, wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 shows a complete floating barrier system with three
partially penetrable auxiliary barriers disposed upstream.
[0019] FIG. 2 shows a segment of the floating barrier system
showing that the individual auxiliary barriers can have varying
degree of perforation.
[0020] FIG. 3 shows a segment of the floating barrier system
showing that the individual auxiliary barriers have horizontally
varying degrees of perforation.
[0021] FIG. 4 shows a segment of the floating barrier system
showing that the individual auxiliary barriers have varying
draught.
[0022] FIG. 5 shows a segment of the floating barrier system
showing that the individual auxiliary barriers have built-in
vertical crossbars.
[0023] FIG. 6 shows a segment of the floating barrier system
showing that the individual auxiliary barriers are provided with
varying spacing.
DETAILED DESCRIPTION OF THE INVENTION
[0024] In the explanation of the Figures, identical or
corresponding elements will be provided with the same designations
in different Figures. Therefore, no explanation of all details will
be given in connection with each single Figure/embodiment.
[0025] In FIGS. 1-5 is seen the conventional floating barrier 1
which in this system is arranged in U-shape. To this is fastened
auxiliary barriers 2, 3, and 4 in upstream direction. The
conventional floating barrier is provided with consecutive buoyant
bodies 5 which may be air-filled or with a permanent buoyancy
means, e.g. plastic foam. These have the purpose of ensuring a
stable position for the floating barrier at sea, also by possible
wave action. The submerged part 6 is constituted by an impenetrable
wall of e.g. reinforced rubber or plastic film. Typically, the wall
has a draught corresponding to 0.5 to 1.5 times the diameter of the
buoyant bodies (the freeboard). Along the lower edge of the wall is
fastened a ballast 7 which can be in the form of an iron chain,
lead rope or bolted metal blocks. The purpose of the ballast is to
contribute to the stable position of the floating barrier at sea
and to ensure vertical position of the submerged part. The
auxiliary barriers 2, 3 and 4 on FIGS. 1-5 are also provided with
buoyancy means 8 and ballast 9 which have the same functions as in
the conventional floating barrier.
[0026] In FIG. 2 is shown that the auxiliary barriers 2, 3 and 4
have different degree of perforation 10, 11 and 12 providing
varying penetrability for a liquid flow. The degree of perforation
of the auxiliary barriers will typically be between 60 and 90%.
This means that the open area constitutes between 60 and 90% of the
total area of the submerged part. In the embodiment shown here,
auxiliary barrier 2 which is disposed farthest upstream has a
preferred degree of perforation of 75-85%, auxiliary barrier 3 a
degree of perforation of 70-80% and auxiliary barrier 4 a degree of
perforation of 65-75%.
[0027] In FIG. 3 is shown that the auxiliary barriers 2, 3 and 4
have horizontally varied degree of perforation 13 and 14,
respectively. The preferred embodiment of the latter entails that
the flanks of the auxiliary barrier will have an angling relative
to the liquid flow encountering the centre line of the floating
barrier system will have a degree of perforation which compensates
for this fact. This means that the projected degree of perforation
becomes the same as in the central part of the auxiliary barrier.
The performed perforation can either be made as stepwise variations
or as a successive variation.
[0028] In FIG. 4 is shown that the auxiliary barriers have varied
draughts 15, 16, and 17, respectively. In the embodiment preferred
here, auxiliary barrier 15 is reduced to between 60 ad 90% of the
draught of the conventional floating barrier. Auxiliary draught 16
is reduced to between 70 and 100% and auxiliary barrier 17 to
between 80 and 100%.
[0029] In FIG. 5 appears that the individual auxiliary barriers are
provided with vertical crossbars 18. In the embodiment shown here,
these are disposed with spacing (d) corresponding to 100-450% of
the total height (e) of the auxiliary barriers.
[0030] In FIG. 6 is shown that the spacing (a) and (b) of the
individual auxiliary barriers and the distance to the conventional
floating barrier (c) are varied. In the preferred embodiment here,
the spacings between the individual auxiliary barriers 2, 3 and 4
are made such that the spacing (b) is between 80 and 150% of the
spacing (c), and the spacing (a) is between 80 and 150% of the
spacing (b).
* * * * *