US20120145373A1 - Firetube having thermal conducting passageways - Google Patents
Firetube having thermal conducting passageways Download PDFInfo
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- US20120145373A1 US20120145373A1 US13/324,938 US201113324938A US2012145373A1 US 20120145373 A1 US20120145373 A1 US 20120145373A1 US 201113324938 A US201113324938 A US 201113324938A US 2012145373 A1 US2012145373 A1 US 2012145373A1
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- Prior art keywords
- firetube
- fluid
- flowpath
- passageways
- vessel
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F13/00—Arrangements for modifying heat-transfer, e.g. increasing, decreasing
- F28F13/06—Arrangements for modifying heat-transfer, e.g. increasing, decreasing by affecting the pattern of flow of the heat-exchange media
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H1/00—Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
- F24H1/18—Water-storage heaters
- F24H1/20—Water-storage heaters with immersed heating elements, e.g. electric elements or furnace tubes
- F24H1/205—Water-storage heaters with immersed heating elements, e.g. electric elements or furnace tubes with furnace tubes
- F24H1/207—Water-storage heaters with immersed heating elements, e.g. electric elements or furnace tubes with furnace tubes with water tubes
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H9/00—Details
- F24H9/0005—Details for water heaters
- F24H9/001—Guiding means
- F24H9/0015—Guiding means in water channels
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H9/00—Details
- F24H9/0005—Details for water heaters
- F24H9/001—Guiding means
- F24H9/0026—Guiding means in combustion gas channels
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
- F28D21/0001—Recuperative heat exchangers
- F28D21/0003—Recuperative heat exchangers the heat being recuperated from exhaust gases
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D7/00—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall
- F28D7/06—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits having a single U-bend
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D7/00—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall
- F28D7/10—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being arranged one within the other, e.g. concentrically
- F28D7/12—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being arranged one within the other, e.g. concentrically the surrounding tube being closed at one end, e.g. return type
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F2250/00—Arrangements for modifying the flow of the heat exchange media, e.g. flow guiding means; Particular flow patterns
- F28F2250/04—Communication passages between channels
Definitions
- Embodiments of the invention relate to indirect-fired and direct-fired heat exchangers and more particularly to firetubes installed in process vessels, the firetubes having enhanced surface area for heating process fluids.
- U-shaped “firetubes” are common heat exchangers for use in vessels containing fluids to be heated, such as heater-treaters, free water knock-out vessels, and in-line heaters and tanks.
- the U-tube firetube is made of round steel pipe.
- a burner supplies a flame and hot exhaust gases for circulation through the firetube from an inlet to an outlet. Heat is conducted from the pipe walls to the fluid contained in the vessel.
- heat is transferred through the firetube wall immersed directly in a process fluid to be heated, the process fluid being contained in the vessel and in direct contact with the outside of the firetube.
- heat is transferred from the firetube to an intermediate heat exchange fluid.
- a fluid-to-fluid heat exchanger contains the process fluid, the exchanger being immersed in the heat exchange fluid.
- U-tube firetubes have the burner mounted at the gas inlet end of the firetube.
- a vent or exhaust stack is connected to the gas outlet. Both the gas inlet and gas outlet are mounted in a common wall of the vessel.
- the U-tube exchanger is generally installed inside the vessel through an oval or obround shaped manway.
- the ultimate objective in any fired heating system is to create the highest thermal input possible for a given space.
- the thermal input is related in part to the surface area exposed to the hot exhaust gases on one side of the firetube wall and the fluid to be heated on the other side.
- Use of round pipe to create the U-tube firetube results in a very inefficient heat exchanger as the surface area presented to the intended fluid is limited.
- a significant amount of the available heat, imparted by the flame is lost as hot exhaust gases flow through the firetube and up the stack.
- conventional U-tube firetubes are expensive to operate, waste energy used to generate the heat, typically do not optimally utilize the heat generated, and release large amounts of waste gas to the environment.
- embodiments of firetubes have an increased surface area without resulting in an overall increase in the size of the firetube due to a plurality of thermally conducting passageways which extend through the firetube and direct fluids to be heated therethrough.
- Each of the passageways has a wall for heat transfer which adds to the external surface area of the firetube resulting in the increased surface area.
- fluids are caused to rise through the passageways as a result of a temperature differential in the vessel creating a natural convective circulation or thermosiphon effect, the fluids below the firetube being cooler and more dense and the fluids above being warmer and less dense.
- Embodiments of the firetube are suitable for use in direct and indirect-fired vessels.
- process fluids comprise emulsions of water and hydrocarbons having different coefficients causing them to expand and contract at different rates
- expansion and contraction as the fluid enters and leaves the relatively small diameter passageways aids in coalescence of like molecules, which assists in separation of the different constituents a vessel.
- a firetube is adapted to extend horizontally into a vessel for heating fluid therein.
- the firetube has a gas inlet, a gas outlet and at least one flowpath therebetween and conducts hot gases along the flowpath from the gas inlet to the gas outlet.
- the firetube comprises a plurality of passageways, spaced along the flowpath for passing fluid upwardly therethrough. Each passageway extends generally upwardly from a fluid inlet at a lower portion to a fluid outlet at an upper portion and has a thermally conductive wall extending through the flowpath for conducting heat from hot gases to the fluid passing therethrough.
- a heat exchanger for a vessel comprises the firetube according to embodiments of the invention.
- the firetube is suitable for use in a direct-fired vessel where the fluid is a process fluid to be heated by the firetube, the firetube being immersed in the process fluid.
- the firetube is also suitable for use in an indirect-fired vessel where the fluid is a heat transfer fluid to be heated by the firetube.
- the heat exchanger further comprises a fluid-to-fluid heat exchanger for flowing the process fluid therethrough, the fluid-to-fluid heat exchanger being immersed in the heat transfer fluid.
- the heat transfer fluid is glycol.
- Embodiments of the firetube are suitable for installing in new vessels or can be used to retrofit existing vessels.
- As the size of the expanded surface area firetube is substantially the same as the existing prior art firetube, it can be simply installed through the existing manway for flanged connection thereto.
- FIGS. 1A-1C illustrate a prior art U-tube firetube, more particularly,
- FIG. 1A is a plan view of the U-tube shown installed in an manway in a front wall of a vessel, a major portion of the vessel having been removed for clarity;
- FIG. 1B is a plan view of a front wall of the vessel according to FIG. 1A , illustrating an inlet and an outlet of the U-tube installed in a front wall of the manway;
- FIG. 1C is an elevation view of the front wall of the oval manway of FIG. 1B illustrating the inlet and the outlet;
- FIG. 2A is a plan view of a cross-section of one embodiment of a U-tube firetube installed in a vessel, a major portion of the vessel having been removed for clarity, the firetube having a dividing wall extending partially along the firetube and being fit with a plurality of thermally conductive passageways;
- FIG. 2B is a side cross-sectional view of one thermally conductive passageway fit to portion of a firetube according to FIG. 2A ;
- FIG. 2C is a cross-sectional view of a firetube in a direct-fired vessel incorporating an embodiment of the thermally conductive passageways;
- FIG. 2D is a cross-sectional view of an firetube in an indirect-fired vessel incorporating an embodiment of the thermally conductive passageways;
- FIG. 3A is a plan view of a cross-section of the U-tube firetube of FIG. 2 , wherein the dividing wall is formed by a plurality of plates between a plurality of the thermally conductive passageways;
- FIG. 3B is an end cross-sectional view through the firetube of FIG. 3A , along section lines A-A;
- FIG. 4 is a plan view of a cross-section of the U-tube firetube of FIG. 3A having a first central divider and additional of the passageways with second and third dividers for forming two generally U-shaped flowpaths in the body;
- FIG. 5 is a perspective view of the firetube according to FIG. 4 , the body being rendered as transparent for greater clarity;
- FIG. 6 is a plan view of a cross-section of a U-tube firetube according to another embodiment, the thermally conductive passageways forming a tortuous flowpath in the body;
- FIG. 7 is a plan view of a cross-section of a conduit firetube according to another embodiment, suitable for retrofit of a vessel having a prior art firetube according to FIG. 1A ;
- FIG. 8 is a side, cross-sectional view of an embodiment of the firetube illustrating a variety of possible profiles for the thermally conductive passageways;
- FIG. 9 is a side, cross-sectional view of the firetube and tubular passageways according to FIG. 3A ;
- FIG. 10 is a fanciful illustration of fluid flow through tubular thermally conductive passageways, from fluid inlets below the firetube to fluid outlets above the firetube;
- FIG. 11 is a fanciful illustration of the fluid flow through the thermally conductive passageways according to FIG. 10 and enhanced by the action of vortex generators mounted adjacent the passageway inlets.
- prior art firetubes 10 are generally U-shaped tubes, having a side-by-side gas inlet 12 and gas outlet 14 at a flanged connection 16 at a front wall 24 of vessel 26 .
- the firetube 10 is generally manufactured from round, steel pipe which is welded together, using welded mitres 18 for forming the “U” at an end 20 .
- the prior art firetube 10 is connected to a manway 22 , typically obround in shape to accommodate the side-by-side inlet 12 and outlet 14 .
- the gas inlet 12 connects therethrough to a burner (not shown) for receiving flame and hot exhaust gases therefrom.
- the outlet 14 connects to an exhaust stack (not shown) for exhausting waste gases therefrom. Flanged connections are typically used throughout.
- Firetubes can be incorporated in new heat exchange vessels or can be used to retrofit existing vessels to upgrade and enhance the efficiency of heat transfer therein.
- Heat transfer surface area is increased over conventional firetubes by providing a plurality of thermally conductive passageways which extend through the firetube. Fluid in the vessel is heated, not only from the periphery of the firetube but also through fluid conducted through the passageways.
- a firetube 30 comprises a hollow shell or body 32 having body walls 38 for containing and directing hot gases G therethrough.
- the firetube 30 is fit into vessel V and immersed in a fluid F contained therein.
- the body walls 38 form a portion of the surface area for heat transfer from the gas G to the fluid F.
- Hot gases G circulate through a flowpath 42 , from a gas inlet 44 at a first end 46 to a gas outlet 48 at a second end 50 .
- a U-shaped flowpath 42 is formed.
- the inlet 44 is adapted for connection to a source of hot gases such as a burner (not shown) and the outlet 48 is adapted for connection to an exhaust stack (not shown).
- the gas inlet 44 and gas outlet 48 are fit to a front or common header wall 34 secured, such as by flanged connection, to the vessel V.
- the firetube 30 can be fit through an obround manway (see FIG. 3B ) and is cantilevered or otherwise supported to extend generally horizontally from the front wall 36 .
- the firetube 30 has a tube end 36 at a farthest extent from the front wall 34 .
- Hot gases G circulate through the flowpath 42 , from the gas inlet 44 to the gas outlet 48 , heating the body walls 38 and transferring the heat to fluid F.
- the firetube body 32 can be a U-shaped conduit (See FIG. 7 ) or a generally open body, the interior of which is then fit with structure for directing the gases.
- Various internal gas-directing structure are illustrated in FIGS. 2A , 3 A and 4 .
- the gas-directing structure avoids short-circuiting of the flowpath 42 and maximizes gas contact with the body walls 38 .
- the gas-directing structure can be a first dividing wall 40 extending partially along the hollow body 32 , from a proximal end at the common header wall 34 , from a location between the gas inlet 44 and outlet 48 , to a distal end located short of the tube end 36 for forming the generally U-shaped flowpath 42 within the body 32 .
- the surface area can be enhanced by further providing a plurality of thermally conductive passageways 52 .
- the passageways are spaced apart along the flowpath 42 and extend through the body 32 from a fluid inlet 62 at lower portion L of the body wall 38 to fluid exit 64 at an upper portion U of the body wall 38 .
- Cooler fluid to be heated, flows upwardly into the fluid inlet 62 from below the firetube 30 to exit each passageway 52 at the fluid exit 64 above the firetube 30 .
- the passageways 52 have a thermally conductive, tubular wall 54 , typically formed of the same material as the body walls 38 , forming an external surface 56 in contact with hot gases G flowing through the flowpath 42 and an internal surface 58 for contacting the fluid F.
- the walls 54 of the plurality of passageways 52 provide additional heat transfer surface over that conventionally provided by the prior art U-tube firetube.
- fluid F circulates from the lower portion L to the upper portion U of the body wall 38 and then back down within the vessel to repeat the cycle. Where no mechanical impetus is provided, the fluid F movement is like a thermosiphon circulation.
- the firetube 30 can be installed, as a retrofit, through the obround manway 22 of an existing vessel V, increasing the vessel's heating capability over its original design rating.
- a plurality of the thermally conductive passageways 52 can be aligned be integrated with the dividing wall 40 .
- the dividing wall 40 is a first wall centrally located between the inlet 44 and outlet 48 .
- the dividing wall 40 can be formed of a plurality of plates 60 , 60 , 60 . . . , each plate 60 being connected between adjacent passageways 52 for directing gases G along the passageways 52 to the tube end 36 .
- the plates 60 urge gases G from the gas inlet 44 to the dividing wall's distal end and back to the gas outlet 48 .
- the plates 60 can be welded between passageways 52 .
- a plurality of the passageways 52 are fit to the firetube 30 along the flowpath 42 for conducting heat from hot gases to the fluid passing therethrough.
- the number of passageways 52 fit to the flowpath 42 is a function of the desired or design surface area of the tubular walls 54 while not overly restricting the flow of gases G therealong.
- a second dividing wall 40 B and third dividing wall 40 C are provided, forming two, side-by-side U-shaped flowpaths 42 , 42 .
- a firetube 30 may or may not have passageways 52 aligned along the first central dividing wall 40 .
- the second and third dividing walls 40 B, 40 C can be connected at distal ends to more particularly direct the flowpaths.
- the second and third dividing walls 40 B, 40 C When connected, the second and third dividing walls 40 B, 40 C form a U-shaped dividing wall 40 U wherein a first flowpath 42 is formed from the gas inlet 44 , between the first and second divider walls 40 , 40 B, and to the gas outlet 48 between the first and third divider walls 40 , 40 C, and a second flowpath 42 is formed from the gas inlet 44 , between the first divider wall 40 and the body walls 38 , and to the gas outlet 48 between the first wall 40 and the body walls 38 .
- a plurality of non-aligned passageways 52 are distributed laterally across the flowpath 42 to access more of the flow of gas G and increase heat transfer recovered therefrom.
- a plurality of thermally conductive passageways 52 can be retrofitted to the otherwise conventional prior art U-shaped firetube 10 of FIG. 1A .
- thermally conductive passageways 52 are used to increase the effective surface area of the heat exchanger 30 , one of skill in the art would appreciate that too many or too large a diameter of thermally conductive passageways 52 may restrict or interfere with the circulation of the hot exhaust gases G within the heat exchanger 30 . Alternatively, too few thermally conductive passageways 52 may not increase the surface area sufficiently to increase heat transfer efficiency. Further, if the internal diameter of each thermally conductive passageways 52 is too small for the fluid F, the flow rate through the passageways 52 can be ineffective or the passageways could become clogged or plugged by the fluid F or contaminants therein.
- each of the passageways 52 could have a diameter in the range of from about 15% to about 18% of the diameter of the gas inlet 44 for achieving effective heat transfer.
- the firetube 30 is immersed in a substantially clean, heat transfer fluid such as glycol.
- a fluid-to-fluid heat exchanger 70 is provided for flowing the process fluid F P therethrough, the fluid-to-fluid heat exchanger 70 being immersed in the heat transfer fluid F.
- Heat transferred from the gas G to the heat transfer fluid F is transferred the process fluid F P .
- the passageways 52 could be made with a smaller diameter than in the direct-fired system.
- additional passageways 52 may be added to further increase the surface area and thus, increase the heat transfer efficiency.
- the thermally conductive passageways 52 can be upright or substantially vertical pipes passing through the body 32 .
- the thermally conductive passageways 52 can have a variety of shapes or profiles when viewed in cross-section, for example those profiles including those shown viewed from left to right, having a narrow fluid inlet 62 with a wide fluid outlet 64 , a wide fluid inlet 62 with a narrow fluid outlet 64 , a narrow fluid inlet 62 and exit 64 with an enlarged intermediate portion, and one having a uniform profile from inlet 62 to outlet 64 .
- each of the plurality of thermally conductive passageways 52 has the fluid inlet 62 , fluidly communicating with the fluid F in the vessel V below the body 32 , and the fluid outlet 64 , fluidly communicating with the fluid F above the body 32 .
- the arrangement of the fluid inlet 62 and outlet 64 permits the fluid F to rise through each passageway 52 and be heated during its passage therethrough. Applicant believes that the fluid to be heated F is circulated through the firetube 30 and vessel V as a result of a temperature differential which exists between the cooler fluid F at the inlet 62 and the warmed fluid at the outlet 64 . The temperature difference would be sufficient to cause a natural convection current or a thermosiphon effect for urging the fluid F to circulate through the plurality of passageways 52 and cause circulation of the fluid F throughout the vessel V.
- the fluid F heats, the fluid F becomes less dense and rises within within each of the passageways 52 , passing therethrough, receiving heat from the tubular wall 54 and rising within the vessel V.
- the heated fluid F exits the outlet 64 at a temperature greater than that of the nominal vessel temperatures and releases heat thereto.
- heated fluid F transfers its heat, the fluid F begins to sink within the vessel V establishing a convective circulation.
- heat transfer can be enhanced from the gas G to the fluid F in the passages 52 by the addition of vortex generators 80 adjacent one or more of the passageway fluid inlets 62 .
- the vortex generators 80 impart a swirl of the fluid rising within the passageway 52 .
- the swirling action acts to increase the retention time of the fluid F within the thermally conductive passageways 52 , permitting more efficient transfer of heat to the fluid F therein.
- the vortex generators 80 cause more cooler or dense fluids, flowing through the passageways 52 , to move from the center of the flow to the outside, effectively creating a laminar flow adjacent the internal surface 58 which aids the heat transfer.
- the heated fluid F becomes hotter, a natural separation of constituents occurs between the dense fluid and less dense fluid. This phenomenon is particularly advantageous when the fluid F is an unstable emulsion.
- the surface area may be increased as much as 50% compared to a conventional U-tube which is sized to be installed in the same size manway.
- the increased surface area is directly reflected in the increased heat which can be transferred to the fluid F in the vessel V.
Abstract
A firetube is immersed in a fluid to be heated and transfers heat from hot gases flowing through the firetube to the fluid surrounding the firetube. The firetube has a plurality of thermally conductive passageways which extend through the firetube for increasing the surface area available for heat transfer. Fluid is conducted through the passageways by a thermosiphon effect resulting from a temperature differential in the vessel, the fluid below the firetube being cooler and denser than fluid above the heat exchanger.
Description
- This application claims the benefit of U.S. provisional application 61/422,810, filed Dec. 14, 2010, and U.S. provisional application 61/434,258, filed Jan. 19, 2011, the entirety of each of which is incorporated herein by reference.
- Embodiments of the invention relate to indirect-fired and direct-fired heat exchangers and more particularly to firetubes installed in process vessels, the firetubes having enhanced surface area for heating process fluids.
- It is known to heat process fluids in a variety of vessels, such as ASME code process vessels, atmospheric bath heaters and tanks. Generally, a heat exchanger is fit within a vessel for heating fluids, such as those commonly handled in oilfield handling and refining operations.
- In the oilfield, U-shaped “firetubes”, referred to as U-tube firetubes or U-tubes, are common heat exchangers for use in vessels containing fluids to be heated, such as heater-treaters, free water knock-out vessels, and in-line heaters and tanks. Traditionally the U-tube firetube is made of round steel pipe. A burner supplies a flame and hot exhaust gases for circulation through the firetube from an inlet to an outlet. Heat is conducted from the pipe walls to the fluid contained in the vessel.
- In a direct-fired vessel, heat is transferred through the firetube wall immersed directly in a process fluid to be heated, the process fluid being contained in the vessel and in direct contact with the outside of the firetube. In an indirect-fired vessel, heat is transferred from the firetube to an intermediate heat exchange fluid. A fluid-to-fluid heat exchanger contains the process fluid, the exchanger being immersed in the heat exchange fluid.
- Conventional U-tube firetubes have the burner mounted at the gas inlet end of the firetube. A vent or exhaust stack is connected to the gas outlet. Both the gas inlet and gas outlet are mounted in a common wall of the vessel. The U-tube exchanger is generally installed inside the vessel through an oval or obround shaped manway.
- The ultimate objective in any fired heating system is to create the highest thermal input possible for a given space. The thermal input is related in part to the surface area exposed to the hot exhaust gases on one side of the firetube wall and the fluid to be heated on the other side. Use of round pipe to create the U-tube firetube results in a very inefficient heat exchanger as the surface area presented to the intended fluid is limited. As a result, a significant amount of the available heat, imparted by the flame, is lost as hot exhaust gases flow through the firetube and up the stack. Thus, conventional U-tube firetubes are expensive to operate, waste energy used to generate the heat, typically do not optimally utilize the heat generated, and release large amounts of waste gas to the environment.
- Further, in instances where the process heating requirements change and more process fluids enter the operation than design load, the only alternative has been to replace the equipment with larger units.
- Clearly there is a need for improved heat exchangers which are capable of efficiently and cost effectively transferring thermal input to fluids to be heated.
- Generally, embodiments of firetubes, disclosed herein, have an increased surface area without resulting in an overall increase in the size of the firetube due to a plurality of thermally conducting passageways which extend through the firetube and direct fluids to be heated therethrough. Each of the passageways has a wall for heat transfer which adds to the external surface area of the firetube resulting in the increased surface area. In an embodiment, fluids are caused to rise through the passageways as a result of a temperature differential in the vessel creating a natural convective circulation or thermosiphon effect, the fluids below the firetube being cooler and more dense and the fluids above being warmer and less dense. Embodiments of the firetube are suitable for use in direct and indirect-fired vessels.
- Advantageously, where process fluids comprise emulsions of water and hydrocarbons having different coefficients causing them to expand and contract at different rates, the expansion and contraction as the fluid enters and leaves the relatively small diameter passageways aids in coalescence of like molecules, which assists in separation of the different constituents a vessel.
- In a broad aspect, a firetube is adapted to extend horizontally into a vessel for heating fluid therein. The firetube has a gas inlet, a gas outlet and at least one flowpath therebetween and conducts hot gases along the flowpath from the gas inlet to the gas outlet. The firetube comprises a plurality of passageways, spaced along the flowpath for passing fluid upwardly therethrough. Each passageway extends generally upwardly from a fluid inlet at a lower portion to a fluid outlet at an upper portion and has a thermally conductive wall extending through the flowpath for conducting heat from hot gases to the fluid passing therethrough.
- Further, a heat exchanger for a vessel comprises the firetube according to embodiments of the invention. The firetube is suitable for use in a direct-fired vessel where the fluid is a process fluid to be heated by the firetube, the firetube being immersed in the process fluid. The firetube is also suitable for use in an indirect-fired vessel where the fluid is a heat transfer fluid to be heated by the firetube. In this case, the heat exchanger further comprises a fluid-to-fluid heat exchanger for flowing the process fluid therethrough, the fluid-to-fluid heat exchanger being immersed in the heat transfer fluid. In embodiments the heat transfer fluid is glycol.
- Embodiments of the firetube are suitable for installing in new vessels or can be used to retrofit existing vessels. As the size of the expanded surface area firetube is substantially the same as the existing prior art firetube, it can be simply installed through the existing manway for flanged connection thereto.
-
FIGS. 1A-1C illustrate a prior art U-tube firetube, more particularly, -
FIG. 1A is a plan view of the U-tube shown installed in an manway in a front wall of a vessel, a major portion of the vessel having been removed for clarity; -
FIG. 1B is a plan view of a front wall of the vessel according toFIG. 1A , illustrating an inlet and an outlet of the U-tube installed in a front wall of the manway; and -
FIG. 1C is an elevation view of the front wall of the oval manway ofFIG. 1B illustrating the inlet and the outlet; -
FIG. 2A is a plan view of a cross-section of one embodiment of a U-tube firetube installed in a vessel, a major portion of the vessel having been removed for clarity, the firetube having a dividing wall extending partially along the firetube and being fit with a plurality of thermally conductive passageways; -
FIG. 2B is a side cross-sectional view of one thermally conductive passageway fit to portion of a firetube according toFIG. 2A ; -
FIG. 2C is a cross-sectional view of a firetube in a direct-fired vessel incorporating an embodiment of the thermally conductive passageways; -
FIG. 2D is a cross-sectional view of an firetube in an indirect-fired vessel incorporating an embodiment of the thermally conductive passageways; -
FIG. 3A is a plan view of a cross-section of the U-tube firetube ofFIG. 2 , wherein the dividing wall is formed by a plurality of plates between a plurality of the thermally conductive passageways; -
FIG. 3B is an end cross-sectional view through the firetube ofFIG. 3A , along section lines A-A; -
FIG. 4 is a plan view of a cross-section of the U-tube firetube ofFIG. 3A having a first central divider and additional of the passageways with second and third dividers for forming two generally U-shaped flowpaths in the body; -
FIG. 5 is a perspective view of the firetube according toFIG. 4 , the body being rendered as transparent for greater clarity; -
FIG. 6 is a plan view of a cross-section of a U-tube firetube according to another embodiment, the thermally conductive passageways forming a tortuous flowpath in the body; -
FIG. 7 is a plan view of a cross-section of a conduit firetube according to another embodiment, suitable for retrofit of a vessel having a prior art firetube according toFIG. 1A ; -
FIG. 8 is a side, cross-sectional view of an embodiment of the firetube illustrating a variety of possible profiles for the thermally conductive passageways; -
FIG. 9 is a side, cross-sectional view of the firetube and tubular passageways according toFIG. 3A ; -
FIG. 10 is a fanciful illustration of fluid flow through tubular thermally conductive passageways, from fluid inlets below the firetube to fluid outlets above the firetube; and -
FIG. 11 is a fanciful illustration of the fluid flow through the thermally conductive passageways according toFIG. 10 and enhanced by the action of vortex generators mounted adjacent the passageway inlets. - As shown in
FIGS. 1A-1C ,prior art firetubes 10 are generally U-shaped tubes, having a side-by-side gas inlet 12 andgas outlet 14 at aflanged connection 16 at afront wall 24 ofvessel 26. Thefiretube 10 is generally manufactured from round, steel pipe which is welded together, using weldedmitres 18 for forming the “U” at anend 20. Theprior art firetube 10 is connected to amanway 22, typically obround in shape to accommodate the side-by-side inlet 12 andoutlet 14. Thegas inlet 12 connects therethrough to a burner (not shown) for receiving flame and hot exhaust gases therefrom. Theoutlet 14 connects to an exhaust stack (not shown) for exhausting waste gases therefrom. Flanged connections are typically used throughout. - Firetubes, according to embodiments disclosed herein, can be incorporated in new heat exchange vessels or can be used to retrofit existing vessels to upgrade and enhance the efficiency of heat transfer therein. Heat transfer surface area is increased over conventional firetubes by providing a plurality of thermally conductive passageways which extend through the firetube. Fluid in the vessel is heated, not only from the periphery of the firetube but also through fluid conducted through the passageways.
- In more detail, and having reference to
FIG. 2A-3B , one embodiment of afiretube 30 comprises a hollow shell orbody 32 havingbody walls 38 for containing and directing hot gases G therethrough. In use, thefiretube 30 is fit into vessel V and immersed in a fluid F contained therein. Thebody walls 38 form a portion of the surface area for heat transfer from the gas G to the fluid F. Hot gases G circulate through aflowpath 42, from agas inlet 44 at afirst end 46 to agas outlet 48 at asecond end 50. - As shown in
FIG. 2A , when the firetube'sgas inlet 44 andgas outlet 48 are located side-by-side, aU-shaped flowpath 42 is formed. As is also the case in the prior art, theinlet 44 is adapted for connection to a source of hot gases such as a burner (not shown) and theoutlet 48 is adapted for connection to an exhaust stack (not shown). Thegas inlet 44 andgas outlet 48 are fit to a front orcommon header wall 34 secured, such as by flanged connection, to the vessel V. Thefiretube 30 can be fit through an obround manway (seeFIG. 3B ) and is cantilevered or otherwise supported to extend generally horizontally from thefront wall 36. Thefiretube 30 has atube end 36 at a farthest extent from thefront wall 34. - Hot gases G circulate through the
flowpath 42, from thegas inlet 44 to thegas outlet 48, heating thebody walls 38 and transferring the heat to fluid F. - The
firetube body 32 can be a U-shaped conduit (SeeFIG. 7 ) or a generally open body, the interior of which is then fit with structure for directing the gases. Various internal gas-directing structure are illustrated inFIGS. 2A , 3A and 4. The gas-directing structure avoids short-circuiting of theflowpath 42 and maximizes gas contact with thebody walls 38. With reference toFIG. 2A , the gas-directing structure can be afirst dividing wall 40 extending partially along thehollow body 32, from a proximal end at thecommon header wall 34, from a location between thegas inlet 44 andoutlet 48, to a distal end located short of thetube end 36 for forming the generallyU-shaped flowpath 42 within thebody 32. Whether thebody 32 is a U-tube conduit (FIG. 7 ) or fit with one ormore dividing walls 40, the surface area can be enhanced by further providing a plurality of thermallyconductive passageways 52. - Best seen in
FIG. 2B , the passageways are spaced apart along theflowpath 42 and extend through thebody 32 from afluid inlet 62 at lower portion L of thebody wall 38 tofluid exit 64 at an upper portion U of thebody wall 38. Cooler fluid, to be heated, flows upwardly into thefluid inlet 62 from below thefiretube 30 to exit eachpassageway 52 at thefluid exit 64 above thefiretube 30. Thepassageways 52 have a thermally conductive,tubular wall 54, typically formed of the same material as thebody walls 38, forming anexternal surface 56 in contact with hot gases G flowing through theflowpath 42 and aninternal surface 58 for contacting the fluidF. The walls 54 of the plurality ofpassageways 52 provide additional heat transfer surface over that conventionally provided by the prior art U-tube firetube. - As shown in
FIG. 2C , fluid F circulates from the lower portion L to the upper portion U of thebody wall 38 and then back down within the vessel to repeat the cycle. Where no mechanical impetus is provided, the fluid F movement is like a thermosiphon circulation. - Noteably, such an increase in the heat-transferring surface area is accomplished without an increase in the overall size of the
firetube 30. Thus, in an embodiment, thefiretube 30 can be installed, as a retrofit, through theobround manway 22 of an existing vessel V, increasing the vessel's heating capability over its original design rating. - In an embodiment, as shown in
FIGS. 3A and 3B , a plurality of the thermallyconductive passageways 52 can be aligned be integrated with the dividingwall 40. As shown, the dividingwall 40 is a first wall centrally located between theinlet 44 andoutlet 48. Accordingly, the dividingwall 40 can be formed of a plurality ofplates plate 60 being connected betweenadjacent passageways 52 for directing gases G along thepassageways 52 to thetube end 36. Theplates 60 urge gases G from thegas inlet 44 to the dividing wall's distal end and back to thegas outlet 48. Theplates 60 can be welded betweenpassageways 52. In addition, a plurality of thepassageways 52 are fit to thefiretube 30 along theflowpath 42 for conducting heat from hot gases to the fluid passing therethrough. - The number of
passageways 52 fit to theflowpath 42 is a function of the desired or design surface area of thetubular walls 54 while not overly restricting the flow of gases G therealong. - In another embodiment, shown in
FIGS. 4 and 5 , asecond dividing wall 40B andthird dividing wall 40C are provided, forming two, side-by-sideU-shaped flowpaths FIG. 6 , afiretube 30 may or may not havepassageways 52 aligned along the firstcentral dividing wall 40. The second and third dividingwalls walls first flowpath 42 is formed from thegas inlet 44, between the first andsecond divider walls gas outlet 48 between the first andthird divider walls second flowpath 42 is formed from thegas inlet 44, between thefirst divider wall 40 and thebody walls 38, and to thegas outlet 48 between thefirst wall 40 and thebody walls 38. - Returning to
FIG. 6 , in an embodiment having acentralized dividing wall 40, withoutpassageways 52 integrated therein, a plurality ofnon-aligned passageways 52 are distributed laterally across theflowpath 42 to access more of the flow of gas G and increase heat transfer recovered therefrom. - Having reference to
FIG. 7 , alternatively, a plurality of thermallyconductive passageways 52 can be retrofitted to the otherwise conventional prior artU-shaped firetube 10 ofFIG. 1A . - While the plurality of thermally
conductive passageways 52 are used to increase the effective surface area of theheat exchanger 30, one of skill in the art would appreciate that too many or too large a diameter of thermallyconductive passageways 52 may restrict or interfere with the circulation of the hot exhaust gases G within theheat exchanger 30. Alternatively, too few thermallyconductive passageways 52 may not increase the surface area sufficiently to increase heat transfer efficiency. Further, if the internal diameter of each thermallyconductive passageways 52 is too small for the fluid F, the flow rate through thepassageways 52 can be ineffective or the passageways could become clogged or plugged by the fluid F or contaminants therein. - In the case of direct-fired systems, shown in
FIG. 2C , where thefiretube 30 is immersed in a process fluid FP, thepassageways 52 could be prone to plugging by contaminants entrained within the process fluids FP passing therethrough. For conventional oilfield operations, Applicant believes that each of thepassageways 52 could have a diameter in the range of from about 15% to about 18% of the diameter of thegas inlet 44 for achieving effective heat transfer. - In the case of indirect-fired systems, shown in
FIG. 2D , thefiretube 30 is immersed in a substantially clean, heat transfer fluid such as glycol. A fluid-to-fluid heat exchanger 70 is provided for flowing the process fluid FP therethrough, the fluid-to-fluid heat exchanger 70 being immersed in the heat transfer fluid F. Heat transferred from the gas G to the heat transfer fluid F is transferred the process fluid FP. Having minimized risk of clogging of thepassageways 52, as clean fluid F flows therethrough, thepassageways 52 could be made with a smaller diameter than in the direct-fired system. Further, in the indirect-fired systems,additional passageways 52 may be added to further increase the surface area and thus, increase the heat transfer efficiency. - As shown in
FIG. 8 , in embodiments, the thermallyconductive passageways 52 can be upright or substantially vertical pipes passing through thebody 32. Having reference toFIG. 9 , the thermallyconductive passageways 52 can have a variety of shapes or profiles when viewed in cross-section, for example those profiles including those shown viewed from left to right, having anarrow fluid inlet 62 with a widefluid outlet 64, awide fluid inlet 62 with anarrow fluid outlet 64, anarrow fluid inlet 62 andexit 64 with an enlarged intermediate portion, and one having a uniform profile frominlet 62 tooutlet 64. - With reference to
FIGS. 10 and 11 , each of the plurality of thermallyconductive passageways 52 has thefluid inlet 62, fluidly communicating with the fluid F in the vessel V below thebody 32, and thefluid outlet 64, fluidly communicating with the fluid F above thebody 32. The arrangement of thefluid inlet 62 andoutlet 64 permits the fluid F to rise through eachpassageway 52 and be heated during its passage therethrough. Applicant believes that the fluid to be heated F is circulated through thefiretube 30 and vessel V as a result of a temperature differential which exists between the cooler fluid F at theinlet 62 and the warmed fluid at theoutlet 64. The temperature difference would be sufficient to cause a natural convection current or a thermosiphon effect for urging the fluid F to circulate through the plurality ofpassageways 52 and cause circulation of the fluid F throughout the vessel V. - As the fluid F heats, the fluid F becomes less dense and rises within within each of the
passageways 52, passing therethrough, receiving heat from thetubular wall 54 and rising within the vessel V. The heated fluid F exits theoutlet 64 at a temperature greater than that of the nominal vessel temperatures and releases heat thereto. As heated fluid F transfers its heat, the fluid F begins to sink within the vessel V establishing a convective circulation. - In an embodiment, as seen in
FIG. 11 , heat transfer can be enhanced from the gas G to the fluid F in thepassages 52 by the addition ofvortex generators 80 adjacent one or more of thepassageway fluid inlets 62. Thevortex generators 80 impart a swirl of the fluid rising within thepassageway 52. The swirling action acts to increase the retention time of the fluid F within the thermallyconductive passageways 52, permitting more efficient transfer of heat to the fluid F therein. Further, it is believed that thevortex generators 80 cause more cooler or dense fluids, flowing through thepassageways 52, to move from the center of the flow to the outside, effectively creating a laminar flow adjacent theinternal surface 58 which aids the heat transfer. - Further, as the heated fluid F becomes hotter, a natural separation of constituents occurs between the dense fluid and less dense fluid. This phenomenon is particularly advantageous when the fluid F is an unstable emulsion.
- Applicant believes, this is a useful phenomenon in the case of vessels such as heater-treaters and free water knock-out vessels, where separation of hydrocarbons and water can also occur. Applicant believes that the effect of the fluid F entering the
passageways 52, followed by an expansion of the fluid F leaving thepassageways 52, aids in the separation of the hydrocarbons from water. The constituents of the process fluid FP, particularly the hydrocarbons and the water, have different viscosities and heat coefficients causing them to expand and contract at different rates. The expansion and contractions aids in coalescence of like molecules which assists in separation of the different constituents. - In an example, employing embodiments discussed herein, for a process vessel having 2 million British Thermal Unit (BTU) heat exchanger capacity, the surface area may be increased as much as 50% compared to a conventional U-tube which is sized to be installed in the same size manway. The increased surface area is directly reflected in the increased heat which can be transferred to the fluid F in the vessel V.
Claims (17)
1. A firetube adapted to extend horizontally into a vessel for heating fluid therein, the firetube having a gas inlet, a gas outlet and at least one flowpath therebetween, the firetube conducting hot gases along the flowpath from the gas inlet to the gas outlet, the firetube comprising:
a plurality of passageways spaced along the flowpath for passing fluid upwardly therethrough, each passageway extending generally upwardly from a fluid inlet at a lower portion of the firetube to a fluid outlet at an upper portion of the firetube and having a thermally conductive wall extending through the flowpath for conducting heat from the hot gases to the fluid passing therethrough.
2. The firetube of claim 1 wherein the flowpath is generally U-shaped from the gas inlet to the gas outlet.
3. The firetube of claim 2 wherein the generally U-shaped flowpath comprises
a U-tube conduit having the gas inlet adjacent the gas outlet at a common header wall, the plurality of passageways being spaced along the U-tube conduit.
4. The firetube of claim 2 wherein the firetube is a hollow body having body walls, the gas inlet being adjacent the gas outlet at a common header wall, the generally U-shaped flowpath comprising:
at least one dividing wall extending from between the gas inlet and the gas outlet, partially along the hollow body from the common header wall and toward a tube end, wherein
the gases are directed to flow along the U-shaped flowpath from the gas inlet, about a distal end of the at least one dividing wall, and to the gas outlet.
5. The firetube of claim 2 wherein at least some of the plurality passageways are distributed laterally across the flowpath.
6. The firetube of claim 4 wherein
at least some of the plurality of passageways are integral with the at least one dividing wall.
7. The firetube of claim 6 wherein passageways integral with the at least one dividing wall are substantially aligned and connected therebetween by plates to urge gas along the U-shaped flowpath.
8. The firetube of claim 1 wherein the flowpath comprises two side-by-side flowpaths.
9. The firetube of claim 8 wherein the firetube is a hollow body having enclosing body walls, the gas inlet being adjacent the gas outlet at a common header wall, the two, side-by-side flowpaths comprise:
a first dividing wall, intermediate the gas inlet and the gas outlet, and extending from the common header wall toward a tube end,;
a second dividing wall extending from the common header wall intermediate the gas inlet; and
a third dividing wall extending from the common header wall intermediate the gas outlet,
wherein gases flow along the two, side-by-side flowpaths from the gas inlet, about distal ends of the first, second and third dividing walls and to the gas outlet,
10. The firetube of claim 9 wherein:
the distal end of the second dividing wall and the distal end of the third dividing wall art are connected; and wherein
a first flowpath of the side-by-side flowpaths is formed from the gas inlet, between the first and second divider walls, and to the gas outlet between the first and third divider walls, and
a second flowpath of the side-by-side flowpaths is formed from the gas inlet, between the first divider wall and the body walls, and to the gas outlet between the first divider wall and the body walls.
11. The firetube of claim 1 wherein the thermally conductive passageways are pipes extending substantially vertically through the firetube.
12. The firetube of claim 1 further comprising a vortex generator at one or more of the passageway fluid inlets.
13. A heat exchanger for a vessel comprising the firetube of claim 1 , wherein
the vessel is a direct-fired vessel and the fluid is a process fluid to be heated by the firetube, the firetube being immersed in the process fluid.
14. The heat exchanger of claim 13 wherein each of the plurality of passageways has a diameter from about 15% to about 18% of a diameter of the inlet.
15. A heat exchanger for a vessel comprising the firetube of claim 1 , wherein
the vessel is an indirect-fired vessel and the fluid is a heat transfer fluid to be heated by the firetube, the heat exchanger further comprising a fluid-to-fluid heat exchanger for flowing a process fluid therethrough, the fluid-to-fluid heat exchanger being immersed in the heat transfer fluid.
16. The heat exchanger of claim 15 wherein the heat transfer fluid is glycol.
17. The heat exchanger of claim 13 wherein
the firetube is obround in cross-section and is installed through an obround manway formed in the vessel.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/324,938 US20120145373A1 (en) | 2010-12-14 | 2011-12-13 | Firetube having thermal conducting passageways |
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
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US42281010P | 2010-12-14 | 2010-12-14 | |
US201161434258P | 2011-01-19 | 2011-01-19 | |
US13/324,938 US20120145373A1 (en) | 2010-12-14 | 2011-12-13 | Firetube having thermal conducting passageways |
Publications (1)
Publication Number | Publication Date |
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US20120145373A1 true US20120145373A1 (en) | 2012-06-14 |
Family
ID=46198136
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US13/324,938 Abandoned US20120145373A1 (en) | 2010-12-14 | 2011-12-13 | Firetube having thermal conducting passageways |
Country Status (2)
Country | Link |
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US (1) | US20120145373A1 (en) |
CA (1) | CA2761537A1 (en) |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2016024005A1 (en) * | 2014-08-14 | 2016-02-18 | Munster Simms Engineering Limited | Heating apparatus |
US20170355006A1 (en) * | 2016-06-14 | 2017-12-14 | Global Vessel & Tank, LLC | Flange Assembly for Heater Treaters and Other Vessels |
WO2018118452A1 (en) * | 2016-12-22 | 2018-06-28 | Trinity Endeavors, Llc | Fire tube |
US20180352818A1 (en) * | 2015-02-03 | 2018-12-13 | Lbc Bakery Equipment, Inc. | Convection oven with linear counter-flow heat exchanger |
GB2529232B (en) * | 2014-08-14 | 2019-03-20 | Munster Simms Eng Ltd | Heat exchanger for heating apparatus |
GB2529231B (en) * | 2014-08-14 | 2019-03-20 | Munster Simms Eng Ltd | Heating apparatus |
US11623164B2 (en) | 2017-10-30 | 2023-04-11 | Red Deer Iron Works Inc. | Horizontal production separator with helical emulsion circulation coils |
US11703282B2 (en) | 2016-12-22 | 2023-07-18 | Trinity Endeavors, Llc | Fire tube |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US729402A (en) * | 1903-01-02 | 1903-05-26 | Jan Hendrik Peelen | Steam-generator. |
US1486888A (en) * | 1923-06-06 | 1924-03-18 | Hawley Charles Gilbert | Steam boiler |
US4197869A (en) * | 1975-04-23 | 1980-04-15 | Moncrieff Yeates Alexander J | Method and apparatus for generating a stable vortex fluid flow pattern |
US4771762A (en) * | 1987-06-08 | 1988-09-20 | Bridegum James E | Water heater for recreational vehicle |
US5921206A (en) * | 1998-08-04 | 1999-07-13 | National Bank Company | Heater for process fluids |
US20080223563A1 (en) * | 2007-03-17 | 2008-09-18 | Charles Penny | U Shaped Cooler |
-
2011
- 2011-12-13 CA CA2761537A patent/CA2761537A1/en not_active Abandoned
- 2011-12-13 US US13/324,938 patent/US20120145373A1/en not_active Abandoned
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US729402A (en) * | 1903-01-02 | 1903-05-26 | Jan Hendrik Peelen | Steam-generator. |
US1486888A (en) * | 1923-06-06 | 1924-03-18 | Hawley Charles Gilbert | Steam boiler |
US4197869A (en) * | 1975-04-23 | 1980-04-15 | Moncrieff Yeates Alexander J | Method and apparatus for generating a stable vortex fluid flow pattern |
US4771762A (en) * | 1987-06-08 | 1988-09-20 | Bridegum James E | Water heater for recreational vehicle |
US5921206A (en) * | 1998-08-04 | 1999-07-13 | National Bank Company | Heater for process fluids |
US20080223563A1 (en) * | 2007-03-17 | 2008-09-18 | Charles Penny | U Shaped Cooler |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2016024005A1 (en) * | 2014-08-14 | 2016-02-18 | Munster Simms Engineering Limited | Heating apparatus |
GB2529232B (en) * | 2014-08-14 | 2019-03-20 | Munster Simms Eng Ltd | Heat exchanger for heating apparatus |
GB2529231B (en) * | 2014-08-14 | 2019-03-20 | Munster Simms Eng Ltd | Heating apparatus |
US10480819B2 (en) | 2014-08-14 | 2019-11-19 | Munster Simms Engineering Limited | Heating apparatus |
US20180352818A1 (en) * | 2015-02-03 | 2018-12-13 | Lbc Bakery Equipment, Inc. | Convection oven with linear counter-flow heat exchanger |
US20170355006A1 (en) * | 2016-06-14 | 2017-12-14 | Global Vessel & Tank, LLC | Flange Assembly for Heater Treaters and Other Vessels |
WO2018118452A1 (en) * | 2016-12-22 | 2018-06-28 | Trinity Endeavors, Llc | Fire tube |
US11371694B2 (en) | 2016-12-22 | 2022-06-28 | Trinity Endeavors, Llc | Fire tube |
US11703282B2 (en) | 2016-12-22 | 2023-07-18 | Trinity Endeavors, Llc | Fire tube |
US11623164B2 (en) | 2017-10-30 | 2023-04-11 | Red Deer Iron Works Inc. | Horizontal production separator with helical emulsion circulation coils |
Also Published As
Publication number | Publication date |
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CA2761537A1 (en) | 2012-06-14 |
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Owner name: CHADWICK ENERGY SOLUTIONS LTD., CANADA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:CHADWICK, THOMAS;REEL/FRAME:027716/0080 Effective date: 20111207 |
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STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |