Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02534697 2006-01-31
PORTABLE DEGASSER, FLARE TA1~TK AND FLUID STORAGE SYS1'EM
Field of the Invention
This invention relates to a portable degasser, flare tank and fluid storage
system
for use during oil well exploratory drilling which can be transported to a
remote site and
connected to fluid blow-out prevention hardware commonly associated with an
active drilling
operation to prevent the accidental spillage of any liquid ejected under
pressure from a drill
bore hole to the environment.
Background of the Invention
As illustrated in Figure 1, conventionally during the process of drilling,
fluid 2
is pumped through the drill pipe 4 into the bore hole 6 for the purposes of
cooling the drill bit
8 and packing or sealing the wall of the bore. It is common in the industry to
use diesel fuel as
an easily accessible and efficient fluid for this purpose. As drilling
proceeds to depth a
considerable voltune of such fluid will be contained within the bore which is
nominally 10
inches (254mm) in diameter. Pockets of pressurized gas are normally
encountered at intervals
during the drilling process. If the fluid pressure of the gas exceeds the
pressure of the drilling
fluid 2, a so-called 'gas kick' will enter the bore hole 6 and the contents of
the bore hole
6incl.uding any diesel fuel/oil mixture or such other liquids commonly used in
the industry, as
well as fragments of rock, loose soil, etc. will be ejected as ejecta from the
surface opening of
the drill bore hole 6under considerable pressure.
Environmental contatnination is an obvious concern resulting from the
expulsion of such mixture from the bore hole as is the health and safety of
workers at the
drilling site. Blow-out prevention hardware is commonly utilized near the
ground surface
surrounding the bore hole site to ameliorate such contamination and safety
concerns. It is
common practice for such hardware to simply contain and direct such expelled
fluid by
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CA 02534697 2006-01-31
suitable pipe-work to nearby storage areas, which may simply be one or more
shallow open
pits excavated nearby. At suitable intervals the conitents of these pits are
ignited and volatile
materials burnt off. It is obvious then that with this practice there is
little regard of the
recovery and subsequent re-use of the fluid used during the drilling process
or for the buming
of the volatile materials in an efficient manner.
The portable degasser, flare tank and fluid storage system of the present
invention, once it has been situated in proximity to an exploratory drilling
rig, may be more
easily connected to the fixed length lines extending from the blow-out
prevention hardware
than was heretofore possible, without the need for accurate positioning of the
portable
degasser.
In the prior art the applicant is aware of United States Patent No. 3,973,930
which issued August 10, 1976 to Burgess for a Drililing Mud Degasser Apparatus
and Method
where a tank for receiving inud from a drilling operation incorporates a
centrifugal separator
mounted therein for separating gas, liquid and solids.
Further, the applicant is aware of LJnited States Patent No. 6,162,284 which
issued December 19, 2000 to Mitchell, Gladue and Corb for a Separator For
Gasses, Liquids
and Solids From a Well by directing ejecta from a bore hole 6created by 'air
drilling' and foam
extraction, to a vortex for centrifugally separating gas, liquid and solids,
thus perinitting
separated gas to be flared off, the solids to be disposed and the liquid to be
reused in the
further drilling process.
The applicant is also aware of Unitecl States Patent No. 6,193,786 which
issued
February 27, 2001 to Henderson for a Portable Oil Degasification Apparatus
where oil
containing a volatile dissolved combustible gas is infused with an inert gas
having a lower
equilibrium vapor pressure to transfer the combustible gas into the inert,
then separating the
volatile/inert gas combination from the oil.
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The teaching in the prior art does not reduce the necessity for, and
difficulty
associated with, repositioning the degassing apparatus, which is heavy and
thus only
transported by means of heavy equipmerit, so that the fixed-length pipes
extending from the
blow-out prevention hardware on the drilling rig can be attached to the
degassing apparatus.
Summary of the Invention
The portable degasser, flare tank and fluid storage system of the present
invention is an apparatus for receiving and separating returning gasses,
liquids and solids from,
for example, an oil well bore hole.
More specifically it pertains to molmting return gas flare lines, return
liquid
lines, a liquid degassing tank and a liquid/solid-receiving compartment within
a readily
portable framework, where the return gas flare lines, return liquid. line and
liquid degassing
tank are reciprocally movable within the portable framework to enable these
components to be
easily repositioned relative to a well being drilleci so that pipelines
connecting prevention
hardware on the drilling rig can be readily attached.
In summary, the portable degasser,, flare tank and fluid storage system in
accordance witli one embodiment of the invenition may be generally
characterized as
including:
(a) an exterior supporting framework;
(b) an open liquid/solid receiving compartment fixedly supported by the
exterior
supporting framework,
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{"c} an open bottonied, generally cylindrical degassing tank niounted on upper
and
lower movable carriages which are carried by the supporting franlework so as
to be movable relative to an end of tliLe framework, where the degassing tank
is
positioned generally medially of the open liquid/solid-receiving compartment
and the open bottom is positioned within the compartment below it's open
upper surface
(d) return liquid lines for example generally four inches in diameter.
connecting the
degassing tanlc to blow-out prevention hardware on a drilling rig,
(e) return gas flare lines for exainple generally eight inches in diameter,
connecting
a blow-out prevention hardware on the drilling rig to the exterior supporting
framework, which are mounted on a movable carriage carried by the supporting
framework and connected to the degassing tank carriage so as to be
reciprocally
movable tlzerewith relative to an end of the framework,
(f) actuation means fixedly mounted to an opposite end of the supporting
framework having actuation cables or other actuation means connected to the
degassing tank for fore and aft reciprocal movement of the degassing tank
(g) a generally cylindrical degassing tank where liquid/solid-receiving lines
are
located in the upper portion of the tank and incoming liquid falls by gravity
to
contact downwardly sloping, inwardly projecting baffles fixed to the sides of
the tank to agitate the liquid sufficiently to release entrained gases.
Stated another way, the present invention may be characterized as a degasser
system for mounting to a pipe or pipes mounted to the blow-out outflow from a
bore hole as to
as to direct ejecta from the bore hole resulting from blow-out into the pipe,
the system
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including: a rigid frame; an open-bottomed vessel rnounted on the frame,
wherein the vessel
has a lower open end, contiguously sealed sidewalls extending upwardly from
the lower open
end, and an enclosed vessel head mounted to so as to seal an upper end of the
sidewalls. The
vessel thus has an interior cavity defined by the sidewalls and the head; a
stack mounted to and
extending from the vessel head, the stack in fluid communication with the
cavity so as to
exhaust gas from the vessel; a pipe coupler mounted to the sidewalls adjacent
the upper end
thereof, the pipe coupler in fluid communication with the vessel cavity and
mountable to the
blow-out outflow pipe or pipes so as to direct the ejecta from the blow-out
outflow pipe or
pipes, when the pipe coupler is mounted to the pipe or pipes, in an in-flow
direction into the
cavity. The ejecta flows along a flow path under force of gravity down through
the vessel in a
downward direction and so as to flow out through the lower open end; at least
one baffle
mounted to the sidewalls and in the cavity so as to partially occlude the
cavity and so as to lie
at least partially across the flow path, whereby the ejecta flowing along the
flow path is
degassed; a tank mounted under the vessel so as to receive the ejecta flowing
from the lower
open end of the vessel whereby the ejecta is stored in the tank for later
removal and disposal;
and, means for translating the pipe coupler and the vessel relative to the
frame so as to thereby
translate the pipe coupler for ease of mounting to the blow-out outflow pipe
or pipes.
The means for translating the pipe coupler and the vessel relative to the
frame
translates the vessel over, and relative to, the tank:. The tank has an
upwardly-open upper
opening sized so that the vessel only translates over the opening. The taiik
may have sidewalls
defining the upper opening into the tank, and the lower open end of the vessel
is thus disposed
over the upper opening between the sidewalls.
The frame may include rails, and the means for translating the pipe coupler
and
the vessel may include means for translating the vessel along the rails. The
rails may include a
spaced apart pair of substantially horizontal rails mounted on opposite sides
of the vessel and
the means for translating the vessel along the rails may include rolling means
such as rollers,
wheels, castors, bearings, etc. mounted to the vessel for rolling along the
rails. The vessel may
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extend downwardly between the pair of substantially horizontal rails so as to
dispose the lower
open end below the rails.
The vessel. has a range of translatory motion along the rails extending
substantially entirely across the upper opening into the tank. A selective
actuation means is
provided for selectively translating the vessel along; the rails. The
selective actuation means
may include at least one elongate element cooperating between the vessel and a
prime mover
mounted to the frame. The elongate element may include at least one cable and
the prime
mover may include at least one winch mounted to one end of the cable. An
opposite end of
the cable may be mounted to the vessei. 'The cable may be formed as a loop so
as to function
as a double-acting actuator moving the vessel back and forth along the rails.
The stack may be pivotally mounted over the head so as to be foldable between
a stowed position adjacent the frame and a deployed position extending
upwardly from the
head. The pipe coupler may be pivotable at an end thereof so as to pivot for
ease of mounting
to the pipe.
The vessel may be elongate and inounted in the frame so as to be elongate
vertically. The at least one baffle may be an array of baffles spaced apart
along the flow path
below the pipe coupler where mounted to the sidewalls. The pipe coupler may be
mounted to
the sidewalls adjacent the upper end of the sidewalls. The array of baffles
may include a
plurality of baffles which are alternatingly mounted to opposite walls of the
sidewalls and so
as to be interleaved along the flow patli alternatingly in opposed facing
array. The plurality of
baffles may include at least three alternatingly opposed-facing downwardly
inclined baffles
interleaved so that distal ends of the baffles are interleaved along the flow
path so that the flow
path is circuitous through the baffles as the ejecta travels along the flow
path through the array
of baffles.
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A blast plate may be mounted in the vessel so as to be in an in-flow of the
ejecta flowing in the in-flow direction from the pipe coupler so as to receive
a blast force of
the ejecta and to deflect the ejecta along the flow path. The pipe coupler,
where it is mounted
to the vessel, may include a substantially horizontal pipe extension extending
through the
sidewalls into the cavity of the vessel. The sidewalls may be formed as an
elongate cylinder
extending from the head to the lower open end.
Brief Description of the Drawings
Figure i is a diagrammatic illustration of a prior art drilling system.
Figure la, is a side elevation view of the portable degasser, flare tank and
fluid
storage system of the present invention in fluid comimunication with a blow-
out control system
mounted in a well-head.
Figure 2 is an enlarged, partially cut-away perspective view of the present
invention.
Figure 3 is a front elevation view of the system of Figure la.
Figure 4 is a rear elevation view of the system of Figure 1 a.
Figure 5 is a plan view of the system of Figure Ia.
Figure 6 is a plan view partially cut away of the system of Figure la.
Figure 7 is a vertical sectional view of the degassing tank.
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Detailed Description of Embodiments of the Invention
With reference to the drawing figures, wherein siinilar characters of
reference
denote corresponding parts in each view, the portable degasser, flare tank and
fluid storage
system. 10 has a fram.e 12. An open-topped ejecta-receiving tank 16 is mounted
in the bottom
of frame 12.
A generally cylindrical degassing vessel 20 is mounted so as to be elongate
vertically on upper and lower carriages 22 and 24 respectively, supported on
rails 26. Rails 26
are mounted horizontally within frame 12. Vessel 20 has an open bottom 20a,
which is
suspended within tank 16, and in particular within upper opening 16a. Vessel
20 is movable
relative to both frame 12 and tank 16 on carriages 22 and 24.
Pipelines 30, which may conventionally be generally four inches in diameter,
is
connected at one end to fittings on blow-out control system 31 on a wellhead
32 on a drilling
rig (not shown). Pipelines 30 carry a slurry of ejecta from a borehole during
the drilling
operation when a pocket of pressurized gas is encountered. The proximal ends
30a of
pipelines 30 enter vessel 20, near its upper end 20b. The slurry enters vessel
20 under pressure
and impacts blast plate 34, best seen in Figure 7, Plate 34 inhibits damage to
vessel 20.
Baffles 36 within vessel 20 assist in removing entrained volatile gas from the
slurry as it flows
under force of gravity downwardly into tank 16. Condenser baffle 38 prohibits
upward travel
of liquid while permitting free upward passage of gas into the flare stack 42.
Flare stack 42 is
hingedly mounted as at 44 to the upper end 20b of vessel 20, perrnitting it to
be collapsed for
transportation.
Actuation means, which in one forxn may be winches 48 and 50, as can be
viewed in Figure 5, is mounted to frame 12. The cable 48a extending from winch
48 is
connected to the near side of vessel 20. Cable 50a extending from winch 50
passes through
guide 52 and around pulleys 54 and is connected to the far side of vessel 20.
Operation of the
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actuation means provides for translating vessel 20 and pipelines 30 back and
forth along rails
26.
Return gas flare lines 60, which may be generally eight inches in diameter,
may
be connected to fittings on the blow-out control system on the drilling rig.
Lines 60 are
mounted to a movable carriage 62 mounted on rails 66. Rails 66 are mounted on
frame 12.
Movable carriage 62 is rigidly connected to upper carriage 22 so as to be
reciprocally movable
therewith.
Return gas flare lines 60 are hinged as at 70 peimitting lines 60 to be
collapsed
for transportation.
In use the ejecta which collects in tarik 16 has to be occasionally emptied.
This
may be accomplished by either pumping it out of the tank, by the use of drain
plugs, by a
combination of both of these or by other means known in the art.
As will be apparent to those skilled in the art in the light of the foregoing
disclosure, many alterations and modifications are possible in the practice of
this invention
without departing from the spirit or scope thereof. Accordingly, the scope of
the invention is
to be construed in accordance with the substance de-~ined by the following
claims.
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