Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02446915 2003-11-17
O~NTAIIdTMENT SYSTEMS
BACKGROUND OF THE IN~IENTION
Ol Oilfield tanks must be emptied periodically into transport tank trucks. The
transfer of fluid
between tank and tank truck may result in spills and create an environmental
hazard either through
a poor connection or from extra fluid being present in the piping once
disconnected. Spill trays are
sometimes used to catch the leaking fluids, and plastic is a common material
to use as it is light,
and is resistant against weather and corrosive materials. A problem with using
plastic, however, is
the possibility that static charge may build during the transfer of fluid to
and from the spill tray,
which may result in a fire or explosion when oilfield fluids are involved.
This invention is
intended to help reduce these risks.
SUMMARY OF THE INDENTION
02 There is therefore provided, according to an aspect of the invention, a
load line spill
containment system comprising a bottom and a surrounding wall forming a spill
tray. In a
further aspect, the spill tray comprises an access in the s~zrrounding wall
for receiving a pipe
having a joint, the spill tray being configured to receive the joint. In a
further aspect, the spill
tray comprises a horizontally elongated access for receiving plural
horizontally separated pipes
each having joints, the spill tray being configured to receive the joints. The
horizontally
elongated access or piping may be covered by a flexible impermeable covering.
In a further
aspect, the bottom comprises a sump. In a further aspect, there is a drain
system, the drain
system comprising a valve and a tube, the valve connected benueen the pipe and
the tube, the
tube being in fluid communication with the sump. The tube may be constructed
to resist
collapsing under negative pressure. In a further aspect, the tube reaches to
the bottom of the
sump but does not touch the bottom of the sump to avoid forming a seal under
negative
pressure. In a further aspect, there is provided a lid adapted for being
supported by the spill
tray and extending over the spill tray. The spill tray may be formed of
plastic. In a further
aspect, the access comprises a hole in one end of the container such that the
top half of the hole
is in the lid and the bottom half is in the bottom, and such that, when the
piping is present and
the lid is closed, the hole is filled.
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03 In a further aspect, there is provided a support saddle, the spill tray
being received and
supported by the support saddle. The support saddle may be generally U-shaped,
and the spill
tray may have a corresponding shape. In a further aspect, the bottom comprises
a downward
oriented protrusion, and the surrounding wall comprises groove in at least one
side of the
surrounding wall, and where the support saddle further comprises a middle
section and two end
sections, the middle section being laterally oriented and having the length
and shape of the
downward oriented protrusion comprised in the bottom, the two end sections
being vertically
oriented and attached to the ends of the middle section, the end sections
having the same shape
as the corresponding side wall, such that the nuddle section receives the
wedge and the
vertically oriented sections receive the surrounding wall such that the
container is supported.
The downward oriented protrusion may comprises the sump.
04 In a further aspect, the load line spill containment system comprises a
ground system,
the ground system comprising a conductor connected to an external ground box
and received
by the spill tray such that when fluid is present, the conductor is in contact
with the Iluid. The
ground box may be further connected to the pipe and to a grounded body. In a
further aspect,
the load line spill containment system comprises a ground system, the ground
system
comprising a conductor connected to the valve and received by the spill tray
such that when
fluid is present, the conductor is in contact with the fluid. The valve may be
further connected
to a grounded body. In a further aspect, the spill tray further comprises a
stabilizing support
outside the access to the spill tray for stabilizing the pipe, where the pipe
is attached to the
stabilizing support. The stabilizing support may be metal and may be connected
to a
stabilizing support saddle.
OS These and other aspects of the invention are described in the detailed
description of the
invention and claimed in the claims that follow.
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3
BRIEF DESCRIPTION OF THE DRAWINGS
06 There will now be described preferred embodiments of the invention, with
reference to the
drawings, by way of illustration only and not with the intention of limiting
the scope of the
invention, in which like numerals denote like elements and in which:
Fig. 1 depicts a front perspective of the bottom of a drip tray;
Fig. 2 depicts a rear perspective of the bottom of Fig. 1;
Fig. 3 depicts a front perspective of a lid of the drip tray;
Fig. 4 depicts a rear perspective of the lid of Fig. 3;
Fig. 5 depicts a drain valve;
Fig. 6 depicts piping entering the drip tray;
Fig. 7 depicts a support used to hold the drip tray and grounding system.
Fig. 8 depicts a perspective of the bottom of a drip tray;
Fig. 9 depicts a front perspective of a lid of the bottom of Fig. 8;
Fig. 10 depicts a rear perspective of a lid of the bottom of Fig. 8; and
Fig. 11 depicts the spill containment system.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
07 In this patent document, the word "comprising" is used in its non-limiting
sense to mean
that items following the word in the sentence are included and that items not
specifically
mentioned are not excluded. The use of the indefinite article "a" in the
claims before an element
means that one of the elements is specified, but does not specifically exclude
others of the
elements being present, unless the context clearly requires that there be one
and only one of the
elements.
08 According to the invention, there is provided a load line spill containment
system 100
comprising a spill tray 102 and a support 104 for receiving the spill tray
102. The spill tray is
comprised of a sloped bottom 106 which also includes a sump 108, a surrounding
wall 110, a
lid 112, and an access for piping 114. To make the spill tray lighter and more
resistant to
corrosion, rust, and other degrading factors, the spill tray is preferably
composed of plastic,
although any other suitable material may be used. The spill tray also
preferably hold more
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4
than 30 L. The lid may be attached by hinges, for example (not shown).
09 As this containment system is to be designed for use with petroleum
products and other
hazardous materials, it is preferable to have a device capable of grounding
the interior of the
container. A ground wire 202 such as a stainless steel wire is attached to a
ground box 204 at
one end, which is in turn attached to an external ground 206. The ground wire
is laid inside the
spill tray 102 and acts to ground any fluid which may be present. The wire 202
can be run
outside the spill tray 102 and connected to a connection accessible from the
outside. This may
be attached to the outside of the wall 110 of the spill tray 102, or to the
support 104 which may
be metal so that it may be attached by welding. The connection may be a
grounding box 204
in which the wire is attached by a screw 210, and a ground wire 202 from an
external source
206 such as a truck or a grounding rod can be easily attached and removed by
another screw
212. Other grounding options may include connecting the wire 202 to the valve
system
(discussed below) which is metal and is connected to metal piping, or by using
metal tubing in
the valve system.
Referring to Fig. 11, the spill tray 102 encloses a connection 402 between
piping 404
connected to a fluid source such as a tank 410, and piping 405 connected to a
fluid destination
412, such as a truck or trailer. This allows the spill tray 102 to contain any
fluid coming from
a poor or faulty connection from tank to truck. There is also provided a valve
406 connected to
a tube 408 running to the bottom of the tray. Onee the transfer of fluid is
complete, the main
valve 414 on the source 410 is closed, and the valve 406 connected to the tube
at the bottom of
the tray is opened while negative pressure from the trailer is still present,
allowing the piping
405 to the trailer 412 to empty itself, and drain any fluid from the drip tray
102 as well. This
valve system also allows samples to be taken by opening the valve and filling
a sample
container from the tube 408 if it is chosen to be flexible. The tubing 408
preferably runs down
into the sump 108, and is protected against to being sealed in the presence of
a vacuum, such
that it will not close as fluid is being sucked out. A v-shaped sump as
depicted in Fig. 5 is
convenient for providing protection against a seal being formed to the bottom
of the tray. The
tubing 408 is just long enough to reach the bottom, but not long enough to
seal against any flat
CA 02446915 2003-11-17
surfaces. The tubing 408 is also chosen to be a tubing that resists collapsing
under negative
pressure. Some options for the tubing 408 include a hard plastic such as PVC,
a braided
stainless steel tube, or a tubing that has an internal metal support and an
outer rubber covering.
11 In one embodiment, the access 114 to the spill tray comprises a hole 116 in
one end of
the spill tray such that the top half of the hole 118 is in the lid 112 and
the bottom half of the
hole 120 is in the bottom, and such that, when the piping 404 is present and
the lid 112 is
closed, the hole 116 is filled. The hole may be made after the spill tray is
formed by using a
hole saw, which allows for the tray to be custom made to the size of piping
being used. The
opposite end of the spill tray comprises an indentation 122 in the bottom and
a protrusion 124
on the top such that, when the lid is closed, the protrusion is filled by the
indentation, and such
that, when the lid is open, the indentation 122 acts as a cradle for piping
from a fluid
destination. Another embodiment allows the protrusion to be replaced by a
flexible material,
such as rubber. This allows the lid to be completely closed while piping is
present which is
useful to keep out rain or snow during adverse weather.
12 In another embodiment, the spill tray 112 comprises grooves 502 in the
surrounding
wall of the container and a wedge 504 downward oriented and extending the
length of the
bottom 106 of the spill tray 102. The wedge, which may also be an extended
dip, may form
the sump 108. The support 104 as depicted in I~ ig. 7 comprises angle iron
laterally oriented
506 the length of the wedge 504 in the bottom of the container and angle iron
vertically
oriented 508 attached or welded to the ends of the laterally oriented angle
iron and are the
length of the grooves in the surrounding wall. As the wedge 504 and the
grooves 502 are
designed to be the same size as the angle iron, and the angle iron is the same
length as the
wedge and grooves, this three-sided structure can receive the spill tray 102
in such a way that
the spill tray is supported from rotating, overturning, or sliding. If a dip
is used instead of a
wedge, then the angle iron along the bottom would be replaced with a similarly
shaped length
of metal. As well, because of warping which may occur during the fabrication
of the support,
it may be convenient to replace one of the vertically oriented angle irons
with a flat piece of
metal. The support need not be metal, simply a material strong enough to hold
the spill tray
CA 02446915 2003-11-17
when full. Metal is convenient, however, because of its strength and grounding
capabilities.
Other options may include multiple wedges or dips along the bottom with a
corresponding
number of lateral supports. This may form a plurality of sumps.
13 To stabilize the piping 404 entering the spill tray I02, it is convenient
to have a
stabilizing support 510 at the access to the spill tray. The stablilizing
support is preferably
made of metal and attached to the angle iron support 104 such as by welding,
although it may
be formed directly onto the plastic spill tray. The advantage of metal is
that, when attached to
piping 404 or 405, the piping will also be grounded when using the grounding
means. The
piping is attached to the stabilizing 510 support using U-bolts 512 for a
strong hold and a
better ground connection, although other means, such as Velcro strips, may
also be used.
14 Another embodiment of the containment system is shown in Figs. 8 and 9.
This
embodiment may or may not incorporate a support, as it is designed to be
shallow and to sit on
the ground under a tank such as a 400-barrel tank, which may have piping close
to the ground.
The drip tray 600 comprises a wall 601 and a sloped bottom 603, which slopes
toward a sump
614. It may, however use Iegs or another type of support to allow for proper
drainage. The
advantage of this embodiment is a shallow bottom, which is convenient for
containing spills
from piping connections along the ground. In this embodiment, the access for
piping 114
comprise an opening 602 in one end of the lid and an opening 604 in the other
end of the lid,
each of which are covered by a flexible covering 608 such that the lid 605 can
be closed once
the piping 610 is connected. The openings 602 and 604 are wide enough to allow
more than
one piping. This design also encloses a connection between piping connected to
a fluid source
and piping connected to a fluid destination. As with the other embodiment, the
piping
connected to a fluid source may also comprise a valve capable of being opened
and closed and
tubing such that excess fluid in the load or in the drip txay may be removed
after the transfer of
fluid. This embodiment also comprises a stabilizing support (not shown) that
attaches to the
drip tray and to the piping by U-bolts. A grounding device 612 may also be
attached.
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CA 02446915 2003-11-17
15 A person skilled in the art could make immaterial modifications to the
invention described
in this patent document without departing from the invention.
