U.S. patent application number 16/157592 was filed with the patent office on 2019-05-02 for horizontal production separator with helical emulsion circulation coils.
The applicant listed for this patent is RED DEER IRONWORKS INC.. Invention is credited to Kelly CHAMBERLAIN, Todd CHAMBERLAIN, Tyson SMITH.
Application Number | 20190126169 16/157592 |
Document ID | / |
Family ID | 66245139 |
Filed Date | 2019-05-02 |
![](/patent/app/20190126169/US20190126169A1-20190502-D00000.png)
![](/patent/app/20190126169/US20190126169A1-20190502-D00001.png)
![](/patent/app/20190126169/US20190126169A1-20190502-D00002.png)
![](/patent/app/20190126169/US20190126169A1-20190502-D00003.png)
![](/patent/app/20190126169/US20190126169A1-20190502-D00004.png)
![](/patent/app/20190126169/US20190126169A1-20190502-D00005.png)
![](/patent/app/20190126169/US20190126169A1-20190502-D00006.png)
![](/patent/app/20190126169/US20190126169A1-20190502-D00007.png)
![](/patent/app/20190126169/US20190126169A1-20190502-D00008.png)
United States Patent
Application |
20190126169 |
Kind Code |
A1 |
SMITH; Tyson ; et
al. |
May 2, 2019 |
HORIZONTAL PRODUCTION SEPARATOR WITH HELICAL EMULSION CIRCULATION
COILS
Abstract
A separator for separating wellbore emulsions into liquid and
gaseous components has helical emulsion preheat coils encircling a
single-cylinder, dual chamber firetube disposed inside a horizontal
separator vessel. In use, emulsion enters the preheat coils before
entering the separator vessel. The flow of emulsion through the
helical coils promotes initial separation of the emulsion by means
of heat transfer and centrifugal flow. Resultant centripetal force
separates lighter gaseous and liquid particles toward the inside of
the helical coils, while heavier emulsion fractions condense toward
the outside of the helical coils. The use of helical preheat coils
and a single-cylinder, dual-chamber firetube eliminate or minimize
abrupt changes in emulsion flow direction that are characteristic
of prior art separators, resulting in reduced wear in both the
coils and the firetube.
Inventors: |
SMITH; Tyson; (Mack, CO)
; CHAMBERLAIN; Todd; (Loma, CO) ; CHAMBERLAIN;
Kelly; (Loma, CO) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
RED DEER IRONWORKS INC. |
RED DEER |
|
CA |
|
|
Family ID: |
66245139 |
Appl. No.: |
16/157592 |
Filed: |
October 11, 2018 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
62578624 |
Oct 30, 2017 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B01D 17/0217 20130101;
B01D 17/042 20130101; B01D 19/0052 20130101 |
International
Class: |
B01D 17/04 20060101
B01D017/04; B01D 17/02 20060101 B01D017/02; B01D 19/00 20060101
B01D019/00 |
Claims
1. A separator assembly comprising: (a) a separator vessel having
an interior chamber, a first end, and a first removable vessel head
associated with said first end of the separator vessel; (b) a
firetube disposed within the interior chamber of the separator
vessel; (c) a burner associated with a first end of the firetube;
and (d) one or more helical coils for receiving a flow of emulsion,
said one or more helical coils being disposed around the
firetube.
2. A separator assembly as in claim 1 wherein the firetube is a
single-cylinder firetube having a lower firetube chamber and an
upper firetube chamber.
3. A separator assembly as in claim 1 wherein the one or more
helical coils are of generally circular configuration as seen in
end view.
4. A separator assembly as in claim 1 wherein the firetube is a
U-shaped firetube.
5. A separator assembly as in claim 4 wherein the one or more
helical coils are of generally circular configuration as seen in
end view.
6. A separator assembly as in claim 4 wherein the one or more
helical coils are of generally elliptical configuration as seen in
end view.
7. A separator assembly as in claim 1 wherein the one or more
helical coils, the firetube, and the first vessel head form a
subassembly that is removable from the interior chamber of the
separator vessel.
8. A separator assembly as in claim 7 wherein the subassembly
further includes the burner.
9. A separator assembly as in claim 1 wherein the first removable
vessel head is a quick-removal vessel head.
10. A separator assembly as in claim 1 wherein the separator vessel
is oriented horizontally.
11. A separator assembly comprising: (a) a separator vessel having
an interior chamber, a first end, and a first removable vessel head
associated with said first end of the separator vessel; (b) a
firetube disposed within the interior chamber of the separator
vessel; (c) a burner associated with a first end of the firetube;
and (d) one or more helical coils for receiving a flow of emulsion,
said one or more helical coils being disposed below the
firetube.
12. A separator assembly as in claim 11 wherein the one or more
helical coils are of generally elliptical configuration.
13. A separator assembly as in claim 12 wherein the one or more
helical coils are contoured for conformation with the shape of the
firetube.
14. A separator assembly as in claim 11 wherein the one or more
helical coils, the firetube, and the first vessel head form a
subassembly that is removable from the interior chamber of the
separator vessel.
15. A separator assembly as in claim 14 wherein the subassembly
further includes the burner.
16. A separator assembly as in claim 11 wherein the first removable
vessel head is a quick-removal vessel head.
17. A separator assembly as in claim 11 wherein the separator
vessel is oriented horizontally.
Description
FIELD
[0001] The present disclosure relates in general to apparatus for
separating fluids from oil and gas wells into liquid and gaseous
components, and relates in particular to horizontally-oriented
production separators for initial heating and centrifugal
separation of emulsion from an oil or gas well prior to entering a
vessel for gravity and pressure separation.
BACKGROUND
[0002] Oil and gas wells typically produce an emulsion comprising,
in varying proportions, hydrocarbon liquids (e.g., crude oil),
hydrocarbon gases (natural gas), and water. Production separators,
which may be horizontally, vertically, or spherically configured,
are commonly used to heat the emulsion in order separate it into
liquid, gaseous, and water fractions.
[0003] One commonly-used production separator circulates emulsion
through a system of U-shaped piping loops disposed inside a
horizontally-oriented pressure vessel. Each piping loop includes a
pair of straight parallel pipe runs connected at one end by a
short-radius 180-degree elbow, with the other ends of the straight
runs (i.e., inlet and outlet ends) being connected to a flanged
vessel head mounted to one end of the pressure vessel (typically by
bolting), and with the elbow ends of all piping loops projecting
from the vessel head into the interior of the vessel. The vessel
head is fitted with suitable piping connections for receiving a
flow of emulsion from a wellhead and flowing the emulsion through
the piping loop system inside the vessel. A U-shaped horizontal
firetube is provided inside the vessel below the piping loop system
to transfer heat to the piping and the emulsion flowing
therethrough. This particular type of separator is sometimes
referred to as a "180-10-pass" design (denoting 10 piping loops
with 180.degree. elbows).
[0004] This type of prior art separator (which is illustrated in
FIG. 1 herein) has a number of practical and operational drawbacks.
For example, it is prone to high internal pipe wear, particularly
at the short-radius 180.degree. elbows. Another drawback is that
the circulating emulsion tends to be further comingled due to the
turbulent flow that unavoidably occurs as the emulsion passes
through the elbows, thus detracting from the efficiency of the
separation process. Furthermore, "U-tube" firetubes tend to corrode
at a high rate, and they do not transfer heat evenly to the
emulsion bath inside the separator vessel. In addition, flanged
vessel heads of the type required for such prior art separators
require a large number of bolts, plus a consumable gasket; for
these reasons, assembly and disassembly of these separators are
time-consuming processes, with considerable care being required
during assembly to ensure a proper seal with the vessel.
BRIEF SUMMARY
[0005] The present disclosure teaches embodiments of a horizontal
production separator that avoid or mitigate one or more the
above-noted problems with conventional firetube separators. In
accordance with one particular embodiment of a separator in
accordance with the present disclosure, emulsion is preheated by
flowing through a generally helical piping coil closely encircling
a single-cylinder, dual-chamber firetube disposed inside a
horizontal separator vessel, promoting initial separation of the
emulsion by means of heat transfer and centrifugal flow. Resultant
centripetal force separates lighter gaseous and liquid particles
toward the inside of the helical coil, while heavier emulsion
fractions condense toward the outside of the helical coil. The
secondary flow within the helical coil promotes less wear,
increases emulsion retention time, and naturally drops pressure.
The helical configuration of the preheat coil and the use of a
single-cylinder, dual-chamber firetube result in reduced wear in
both the coil and the firetube because of the elimination of the
abrupt changes in flow direction (and consequent increases in flow
velocities) that characterize prior art separators due to their use
of tight-radius piping bends.
[0006] The helical preheat coil serves as an initial phase of the
emulsion separation process. Preferably, the coil will surround the
firetube with little or no separation therebetween, in order to
optimize heat transfer from the firetube to the coil by both
radiant and conductive heating. Exhaust from the firetube is
economized to reduce paraffin build-up in a high-pressure vertical
scrubber associated with the separator vessel.
[0007] In preferred embodiments, the separator has "quick-removal"
vessel heads at one or both ends of the separator vessel, for
quicker and easier assembly and disassembly than for conventional
bolt-on vessel heads. The helical coil and the single firetube are
affixed to one of the quick-removal vessel heads, thus allowing for
quick and easy removal of these components for inspection and
cleaning.
[0008] In one variant embodiment in accordance with the present
disclosure, the subassembly of the helical coil, the firetube, and
the quick-removal vessel head can be adapted for retrofitting into
a conventional horizontal separator, replacing the original
straight-run emulsion tubing, U-shaped firetube, and bolt-on vessel
head.
[0009] Accordingly, in a first aspect the present disclosure
teaches a separator assembly comprising: [0010] a separator vessel
having an interior chamber, a first end, and a first removable
vessel head associated with said first end of the separator vessel;
[0011] a firetube disposed within the interior chamber of the
separator vessel; [0012] a burner associated with a first end of
the firetube; and [0013] one or more helical coils for receiving a
flow of emulsion, said one or more emulsion coils being disposed
around the firetube.
[0014] In one embodiment, the firetube may be a single-cylinder
firetube having a lower firetube chamber and an upper firetube
chamber, with the one or more helical coils being of generally
circular configuration as seen in end view.
[0015] In alternative embodiments, the firetube may be a U-shaped
firetube, with the one or more helical coils being either of
generally circular configuration as seen in end view, or of
generally elliptical configuration as seen in end view.
[0016] The one or more helical coils, the firetube, and the first
vessel head may be arranged so as to form a subassembly that is
removable from the interior chamber of the separator vessel.
Optionally, the subassembly may include the burner.
[0017] Optionally, the first removable vessel head may be a
quick-removal vessel head.
[0018] The separator vessel may be oriented horizontally, but this
is not essential. Depending on the operational requirements and
constraints of a given installation, the separator vessel could
have a non-horizontal orientation (e.g., vertical).
[0019] In a second aspect, the present disclosure teaches a
separator assembly comprising: [0020] a separator vessel having an
interior chamber, a first end, and a first removable vessel head
associated with said first end of the separator vessel; [0021] a
firetube disposed within the interior chamber of the separator
vessel; [0022] a burner associated with a first end of the
firetube; and [0023] one or more helical coils for receiving a flow
of emulsion, said one or more helical coils being disposed below
the firetube.
[0024] The firetube below which the one or more helical coils are
disposed may be either a single-cylinder firetube or a U-shaped
fire tube. The one or more helical coils may be of generally
elliptical configuration, and optionally may be contoured for
conformation with the shape of the firetube.
[0025] Separators in accordance with the present disclosure can be
configured in sizes and orientations similar to existing separator
designs, with changes to internal retention and economizing the
exhaust to achieve optimal heat transfer. Initial emulsion flow is
routed through helical coils that wrap around the single
cylindrical fire tube. The tight arrangement of coils, that
completely wrapping around the fire tube, conducts and radiates
heat through to the fluid, heating it to allow pressure reduction
from the wellhead into the vertical gas scrubber.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Embodiments in accordance with the present disclosure will
now be described with reference to the accompanying Figures, in
which numerical references denote like parts, and in which:
[0027] FIG. 1 illustrates the vessel head, emulsion piping
assembly, and U-shaped firetube of a prior art "180-10-pass"
separator, shown extracted from one end of the separator
vessel.
[0028] FIG. 2 is an exploded view of a first embodiment of a
separator in accordance with the present disclosure, with helical
emulsion piping coils disposed around a single-cylinder,
dual-chamber firetube, and having quick-removal vessel heads.
[0029] FIG. 3 is an oblique longitudinal cross-section through the
separator shown in FIG. 2.
[0030] FIG. 4 is side view of the separator shown in FIG. 2.
[0031] FIG. 4A is a partially-exploded version of FIG. 4,
illustrating removal of the vessel head at one end of the separator
vessel, and removal of the vessel head/firetube/emulsion piping
subassembly from the other end of the separator vessel.
[0032] FIG. 5 is an isometric view of an exemplary embodiment of a
helical emulsion piping coil in accordance with the present
disclosure.
[0033] FIG. 6 is an exploded view of a second embodiment of a
separator in accordance with the present disclosure, with
"flattened" helical emulsion piping coils configured to closely
surround a conventional U-shaped firetube.
[0034] FIG. 7 is an isometric view of the separator in FIG. 6,
fully assembled.
[0035] FIG. 8 is an isometric view of an alternative embodiment of
a vessel head/firetube/emulsion piping subassembly in accordance
with the present disclosure, with a quick-removal head carrying a
conventional U-shaped firetube surrounded by a helical emulsion
piping coil.
DESCRIPTION
[0036] The construction and operation of separator embodiments in
accordance with the present disclosure will be readily apparent to
persons of ordinary skill in the art, having regard to the
accompanying Figures.
[0037] Having reference to the embodiment illustrated in FIGS. 2-4,
separator 100 includes a horizontal separator vessel 110 having an
interior chamber 112, a helical primary emulsion preheat coil 120,
and a helical secondary emulsion preheat coil 130, with helical
emulsion coils 120 and 130 being coaxially disposed around a
dual-chamber, single-cylinder firetube 140 having a lower firetube
chamber 142 and an upper firetube chamber 144. A burner 146
(typically gas-fired) is provided in association with the outer end
of lower firetube chamber 142. A first quick-removal vessel head
116 is provided at the burner end of vessel 110, and a second
quick-removal vessel head 114 is preferably provided at the other
end of vessel 110.
[0038] During operation of separator 100, emulsion from a wellhead
enters primary preheat coil 120 via a preheat inlet 122 and flows
to a choke (not shown) that reduces the pressure in primary preheat
coil 120 to a predetermined level. This completes the first phase
of the emulsion heating process. The emulsion then exits the choke
and enters secondary preheat coil 130 for the second heating
phase.
[0039] After the emulsion has gone through the second heating
phase, it enters a control valve (not shown) which controls
emulsion flow to separator vessel 110. The emulsion will then enter
a vertical high-pressure bottle 160 located above an economized
exhaust 150 that extends from upper firetube chamber 144 and runs
horizontally above vessel 110. The emulsion will then start to
separate by means of pressure and gravity in high-phase bottle 160.
Comingled emulsion will then dump into the emulsion bath inside
interior chamber 112 of vessel 110 where emulsion coils 120 and 130
and firetube 140 are located, in order to maintain a constant
separation temperature. Primarily, water and oil will then be
separated out of the emulsion. Secondarily, gas will be separated
from the low-pressure horizontal unit. Emulsion coils 120 and 130
and firetube 140 are carried by quick-removal vessel head 116,
which is sealingly connected to vessel 110.
[0040] Advantages of separators as exemplified by the embodiment
shown in FIGS. 2-4, relative to prior art separators such as the
180-10-pass design, include the following: [0041] Emulsion flows
from the wellhead into the helical coils starting immediate
separation due to centrifugal force and high heat transfer. [0042]
Secondary fluid flow through the helical coils reduces pressure
naturally and promotes better emulsion separation with minimal
internal coil wear, whereas straight-run emulsion piping as in
prior art separators is prone to high internal wear, especially at
small-radius elbows. [0043] The dual-chamber, single-cylinder
firetube transfers and maintains heat better and more efficiently
than prior art U-shaped firetubes, while having a smaller
volumetric footprint (i.e., the emulsion coils and firetube of the
separator in FIGS. 2-4, in combination, take up less volume inside
the vessel than the emulsion piping and firetube of the prior art
separator). [0044] The helical coils wrapped around the
single-cylinder firetube are heated through both conductive and
radiant heating. [0045] The firetube and helical coil configuration
maintains high emulsion retention with a small volumetric footprint
inside the separator vessel. [0046] Compared to conventional
separators of similar size, higher efficiency and higher emulsion
throughput are achievable due to the smaller volumetric footprint
of the internal components (i.e., single-cylinder firetube and
helical coils). [0047] Exhaust economizer routing exhaust through
the vertical scrubber (i.e., high-pressure bottle) and building can
be used to heat low-temperature areas. [0048] Exhaust from the
burner is routed through the vertical scrubber to reduce paraffin
buildup. [0049] Exhaust from the burner may also be routed to heat
the separator control building and thereby reduce or prevent
freezing on sight glasses and valves in the building. [0050]
Quick-removal vessel head allows for quick access to the separator
vessel for inspection and cleaning. [0051] Metal sealing surfaces
on the quick-removal vessel heads facilitate provision of a safe
and efficient seal between the vessel and vessel heads.
[0052] Referring now to FIGS. 6-7, a horizontal separator 200 in
accordance with an alternative embodiment has a separator vessel
210 having an interior chamber 212 mounted above an insulated
burner enclosure 245 which has an interior chamber 247 housing
generally elliptical (or "flattened") helical emulsion coils 220
and 230 wrapped around a U-shaped firetube 240 (with associated
burner 242 and exhaust 250). During operation of separator 200,
emulsion is preheated by flowing through emulsion coils 220 and
230, before flowing into interior chamber 212 of vessel 210 for
further separation. Advantages of this design (over and above
previously-noted advantages resulting from the use of helical
emulsion coils instead of straight-run piping with small-radius
elbows) include the fact that the firetube and emulsion piping are
outside of vessel 210, which allows vessel 210 to have a smaller
volume for a given emulsion throughput. At the same time,
sufficient heat can be transferred to vessel 210 to keep paraffins
in the emulsion liquefied.
[0053] FIG. 8 illustrates a subassembly comprising a quick-removal
vessel head 312 and a helical emulsion coil 320 in accordance with
the present disclosure, in combination with a prior art U-shaped
firetube 340. This subassembly can be used to retrofit prior art
separators (such as but not limited to the separator shown in FIG.
1) to obtain the operational benefits of helical emulsion coils
over straight-run emulsion piping, as well as the quick-removal
vessel head, without needing to replace the existing firetube
burner.
[0054] It will be readily appreciated by those skilled in the art
that various modifications to embodiments in accordance with the
present disclosure may be devised without departing from the scope
of the present teachings, including modifications which may use
equivalent structures or materials hereafter conceived or
developed. It is to be especially understood that the scope of the
present disclosure is not intended to be limited to described or
illustrated embodiments, and that the substitution of a variant of
a claimed or illustrated element or feature, without any
substantial resultant change in functionality, will not constitute
a departure from the scope of the disclosure.
[0055] Athough the specific embodiments described and illustrated
herein relate to horizontally-oriented, high-pressure separators,
this is by way of non-limiting example only. Persons of ordinary
skill in the art will appreciate that principles and concepts
associated with the specific embodiments disclosed herein may also
be adapted and applied to separators of different physical
configurations (such as but not limited to vertically-oriented
separators) without departing from the scope of the present
disclosure, and that the practical applicability of such principles
and concepts is not limited to or restricted by any particular
range of operating pressures.
[0056] In this patent document, any form of the word "comprise" is
to be understood in its non-limiting sense to mean that any element
or feature following such word is included, but elements or
features not specifically mentioned are not excluded. A reference
to an element by the indefinite article "a" does not exclude the
possibility that more than one such element is present, unless the
context clearly requires that there be one and only one such
element. Any use of any form of the terms "connect", "engage",
"couple", "attach", or any other term describing an interaction
between elements is not meant to limit the interaction to direct
interaction between the subject elements, and may also include
indirect interaction between the elements such as through secondary
or intermediary structure.
[0057] Relational terms such as (but not limited to) "vertical",
"horizontal", "parallel", "elliptical", and "coaxial" are not
intended to denote or require absolute mathematical or geometrical
precision. Accordingly, such terms are to be understood as denoting
or requiring substantial precision only (e.g., "substantially
parallel" or "substantially coaxial") unless the context clearly
requires otherwise. Wherever used in this document, the terms
"typical" and "typically" are to be interpreted in the sense of
representative of common usage or practice, and are not to be
understood as implying essentiality or invariability.
* * * * *