BAFFLE ASSEMBLY FOR A HEAT EXCHANGER, HEAT EXCHANGER INCLUDING THE BAFFLE ASSEMBLY, FLUID HEATING SYSTEM INCLUDING THE SAME, AND METHODS OF MANUFACTURE THEREOF

BACKGROUND

(1) Field

This disclosure relates to fluid heating systems using shell and tube heat exchangers.

(2) Description of the Related Art

Fluid heating systems, including steam, hydronic (water), and thermal fluid boilers, constitute a broad class of devices for producing a heated fluid for use in domestic, industrial, and commercial applications. Because of the desire for improved energy efficiency, compactness, reliability, and cost reduction, there remains a need for improved fluid heating systems, as well as improved methods of manufacture thereof.

SUMMARY

A fluid heating system or heat exchanger baffle assembly comprising: a first tube sheet; a second tube sheet opposite the first sheet; one or more heat exchanger tubes, which connects the first tube sheet and the second tube sheet; and one or more plate baffles and/or one or more annular baffles disposed between the first tube sheet and the second tube sheet, wherein the heat exchanger tubes sealingly pass through the baffles.

Also disclosed is a fluid heating system including a heat exchanger comprising: a pressure vessel; a baffle assembly disposed in the pressure vessel, the baffle assembly comprising a first tube sheet, a second tube sheet opposite the first tube sheet, one or more heat exchanger tubes which connect the first tube sheet and the second tube sheet, an annular baffle and/or a plate baffle disposed between the first tube sheet and the second tube sheet.

Also disclosed is a fluid heating system including a heat exchanger comprising: a pressure vessel; a first tube sheet; a second tube sheet opposite the first sheet; one or more heat exchanger tubes, which connects the first tube sheet and the second tube sheet; one or more plate baffle assemblies disposed between the first tube sheet and the second tube sheet, wherein the heat exchanger tube sealingly passes through the plate baffles; and one or more annular baffle assemblies sealing disposed between the first tube sheet and the second tube sheet, wherein the heat exchanger tubes sealingly pass through the annular baffle.

Also disclosed is a method of producing radial flow in a fluid heating system or heat exchanger heat exchanger, the method comprising: providing a heat exchanger comprising a baffle assembly comprising a pressure vessel shell comprising an inlet and outlet; a baffle assembly entirely disposed in the pressure vessel shell; the baffle assembly comprising a first tube sheet, a second tube sheet opposite the first sheet, one or more heat exchanger tubes which connects the first tube sheet and the second tube sheet; at least one plate baffle disposed between the first tube sheet and the second tube sheet, wherein the heat exchanger tube sealingly passes through the baffle; at least one annular baffle and/or at least one plate baffle sealingly disposed between the first tube sheet and the second tube sheet, wherein the heat exchanger tube sealingly passes through the baffle; and directing a production fluid from the first inlet to the first outlet to provide a flow of the production fluid through the pressure vessel shell to produce the radial flow.

BRIEF DESCRIPTION OF THE DRAWINGS

The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.

The above and other advantages and features of this disclosure will become more apparent by describing in further detail exemplary embodiments thereof with reference to the accompanying drawings, in which:

FIG. 1A is a schematic diagram of an embodiment of a fluid heating system which includes an embodiment of a combustion gas supply system;

FIG. 1B is a color photograph of a region of a fluid heating system shell-and-tube heat exchanger damaged by water boiling near a production fluid baffle;

FIG. 1C is a perspective view of an embodiment of a shell-and-tube heat exchanger incorporating a plate baffle assembly that directs production fluid back-and-forth across the surfaces of adjacent baffle plates;

FIG. 1D is a view of a circular plate baffle where the production fluid is directed across the surface of the plate baffle along a chord;

FIG. 2 is a longitudinal cross-sectional view of an embodiment of a shell-and-tube heat exchanger incorporating a plate baffle assembly;

FIG. 3 is a perspective view of an embodiment of a plate baffle showing the heat exchanger tube holes and the mounting flanges;

FIG. 4 is a side view of an embodiment of a plate baffle assembly showing the plate baffle, the gasket and the retainer with fasteners;

FIG. 5 shows a cross-sectional schematic of an embodiment of a plate baffle assembly showing the gasket seal between the baffle and the outer wall of a heat exchanger tube;

FIG. 6 is a longitudinal cross-sectional view of a shell-and-tube heat exchanger incorporating an annular baffle assembly;

FIG. 7 is a perspective view of an embodiment of an annular baffle showing the heat exchanger tube holes and the mounting flanges;

FIG. 8 shows a cross-sectional schematic of an embodiment of an annular baffle assembly showing the gasket seal between the baffle and the outer wall of a heat exchanger tube, and the gasket seal between the baffle and the inner wall of the pressure vessel;

FIG. 9 is a longitudinal cross-sectional view of an embodiment of a shell-and-tube heat exchanger incorporating an alternating plate and annular baffle assembly;

FIG. 10 is a perspective view of the shell-and-tube heat exchanger of FIG. 9;

FIG. 11 is a perspective rendering of an embodiment of a shell-and-tube heat exchanger incorporating an alternating plate and annular baffle assembly and illustrating the radial flow created by the baffle assembly;

FIG. 12 shows a photograph of a full-scale prototype of a fluid heating system incorporating alternating sealed plate and annular baffles assemblies;

FIG. 13 shows a computational fluid dynamics (CFD) numerical simulation of the flow field through the pressure vessel of an embodiment of a shell-and-tube heat exchanger incorporating an alternating plate and annular baffle assembly and illustrating the radial flow created by the baffle assembly;

FIG. 14A shows a computational fluid dynamics (CFD) numerical simulation of the flow field across the baffle closest to the upper tube sheet with a baffle spacing of 0.75 inches between the baffle and the tube sheet.

FIG. 14B shows a computational fluid dynamics (CFD) numerical simulation of the flow field across the baffle closest to the upper tube sheet with a baffle spacing of 1.25 inches between the baffle and the tube sheet.

DETAILED DESCRIPTION

There remains a need for fluid heating systems which provide more thermally compact designs, e.g., configurations that provide an increased ratio between the power and volume or footprint of the fluid heating systems (FHS), and which can be manufactured at a reasonable cost, with satisfactory material requirements, and reduced complexity. Improvements in the state-of-the-art for fluid heating system design, methods, and manufacture that enable increases in the thermal power achievable for a prescribed size or, conversely, enable a reduction in size for a prescribed thermal power level, accomplished for the same or lower manufacturing cost and complexity, are desirable.

It has been unexpectedly discovered that methods for reducing the size of fluid heating systems incorporating shell-and-tube heat exchangers achieved by increasing the bulk heat flux can exacerbate issues created by the non-uniform temperatures. Areas within the heat exchanger where heat is concentrated can lead to material failures, corrosion, and fouling. Where the temperature exceeds the boiling point of the production fluid, adverse effects may accumulate, particularly near structural joints or cracks that precipitate a production fluid phase change. Not only is the magnitude of the temperature non-uniformity generally increased, but the number of locations or sites has also increased.

Methods for promoting a uniform velocity field within the flow of production fluid through the pressure vessel promote a uniform temperature distribution and efficient exchange of thermal energy across the walls of the heat exchanger tubes. This is achieved in classical heat exchanger design through some form of baffling to direct the production fluid flow, or some other means for controlling the fluid flow in a predictable manner. Baffling may be done in only a few discreet locations to address known issues, or they can be systemic, closely controlling the fluid flow throughout the entire heat exchanger.

Disclosed in FIG. 1A is a schematic of a fluid heating system 100. Ambient air is forced under pressure by a blower 102 through a conduit into a combustor 104, which comprises a furnace 106. In the furnace 106, a sustained combustion of a combination of fuel and air is maintained, releasing heat energy and combustion gases that travel through the upper tube sheet 105 and into a plurality of heat exchanger tubes 115. After traversing the heat exchanger tubes, the hot combustion gases pass through the lower tube sheet 110, into the exhaust plenum 112 bounded by the exhaust plenum shell 114, and through the exhaust port to be conveyed out of the fluid heating system by an exhaust flue (not shown).

The production fluid is forced under pressure into an inlet 116, through the space 155 bounded by the pressure vessel 150 surrounding the heat exchanger tubes and out through the outlet 118. A baffle 108 can be placed around the heat exchanger tubes to direct the flow of production fluid.

The capacity of the fluid heating system is total heat transferred from the thermal transfer fluid to the production fluid under standard conditions. By convention, when the production fluid consists of a liquid (e.g., water, thermal fluid, or thermal oil) the capacity is expressed in terms of British thermal units per hour (BTU/hr); and when the production fluid comprises a gas or vapor (e.g., steam) the standard unit of measurement is expressed in horsepower (HP). In an embodiment wherein the production fluid is a liquid (e.g., water, thermal fluid or thermal oil), the capacity of the fluid heating system may be between 100,000 BTU/hr, or 150,000 BTU/hr, or 200,000 BTU/hr, or 250,000 BTU/hr, or 300,000 BTU/hr, or 350,000 BTU/hr, or 400,000 BTU/hr, or 450,000 BTU/hr, or 500,000 BTU/hr, or 550,000 BTU/hr, or 600,000 BTU/hr, or 650,000 BTU/hr, or 700,000 BTU/hr, or 750,000 BTU/hr, or 800,000 BTU/hr, or 850,000 BTU/hr, or 900,000 BTU/hr to 50,000,000 BTU/hr, or 40,000,000 BTU/hr, or 30,000,000 BTU/hr, or 20,000,000 BTU/hr, or 15,000,000 BTU/hr, or 14,000,000 BTU/hr or 13,000,000 BTU/hr, or 12,000,000 BTU/hr, or 10,000,000 BTU/hr, or 8,000,000 BTU/hr, or 6,000,000 BTU/hr, or 5,000,000 BTU/hr, or 4,000,000 BTU/hr, or 3,000,000 BTU/hr, or 2,000,000 BTU/hr, or 1,000,000 BTU/hr, wherein the foregoing upper and lower bounds can be independently combined. Specifically mentioned is the range from 750,000 BTU/hr to 12,000,000 BTU/hr.

In the fluid heating system, where the production fluid temperature exceeds its heat of vaporization, the production fluid will boil and provide a vapor. This can occur where the flow velocity is low and the production fluid remains in extended contact with the hot surface; for example, near the heat exchanger tubes, or upper or lower tube sheets. While not wanting to be bound by theory, production fluid boiling is understood to cause a loss of thermal efficiency, and sites that regularly experience boiling are also regions where material failure, corrosion and fouling are likely. FIG. 1B shows a region near the upper tube sheet of a standard hydronic boiler where poor flow conditions and high temperatures have routinely resulted in boiling and material degradation of the heat exchanger tubes 115.

It has been unexpectedly discovered that the temperature and mass flow distribution from the furnace into the tubesheet are not homogenous. In all burner configurations, but particularly true for those utilizing premixed surface combustion, there exists temperature and flow gradients. The flow exiting the burner, and driven closest to the furnace will transfer more of its thermal energy into the furnace wall. The resulting temperature boundary layer will flow down the wall, and primarily enter the tubes closest to the perimeter. This results in a mass flow concentration near the perimeter. Contrarily, the rest of the combustion flow will be insulated from the furnace wall, and therefore will retain more of its heat, and generally this hot flow will prefer tubes closest to the center, the magnitude of which was extremely surprising when discovered during CFD modeling of the flow field. This result is so surprising since conventional design practice predicts the turbulence of combustion would promote more even mixing. Additionally, the pressure drop through the length of the tubes would be expected to be much larger in magnitude than the dynamic effects from confined flow, and the flow inside the tubes in highly turbulent. This would be expected to even out the effect on the flow field. Lastly, conventional practice would predict that radiant heat transfer from the hottest gasses in the center (and indeed from the flame itself) would also contribute to increasing the uniformity of the temperature field.

The magnitude of the deviation within gas side temperature field creates uneven heat transfer requirements on the water side of the boiler. Specifically, higher water side heat transfer coefficients (and thus velocity and turbulence) are required near these concentrations of high temperature gas containing tubes.

Most heat exchangers are designed with round cross sections, commonly cylinders. In an embodiment where the production fluid flows across the face of each baffle surface along a chord of the surface, alternating direction across the surface of adjacent baffles (a “back and forth” baffle pattern design), the cross section of flow is small at the entry of a given section (defined by a chord length which is less than the diameter), then increases as it reaches the center of the tube bundle (chord length equal to diameter) and is then reduced again as the fluid reaches the opposite side of the baffle section. FIG. 1C illustrates the production fluid flow corresponding to the configuration described. Production fluid moves through the pressure vessel back-and-forth across the heat exchanger tubes, alternating direction in regions between adjacent baffles by turning the flow 160 at the edges of the baffle plates. FIG. 1D illustrates how the production average fluid flow 165 is directed along chords across the baffles plate through the spaces between adjacent heat exchanger tubes. While such abrupt velocity changes at the edges of the baffles plates to turn the flow direction are not in and of themselves detrimental, the design results in two primary disadvantages.

Firstly, flow momentum dictates that the fluid will try to flow in a straight line. The result is that the tubes at the outside edges 170 tend to receive less flow than those at the center. Secondly, even when the outside tubes are included in the flow (through smart tube patterns, or additional baffling to force flow into these regions), the increase in cross sectional area means that flow velocity is reduced in the center of the bundle. Depending on the configuration of the furnace and heat exchanger tube top sheet, these center tubes are typically the hottest and already at the highest risk of failure.

While not wanting to be bound by theory, these effects are especially pronounced in single-pass, in-line heat exchangers incorporating conventional mesh burners for firetube boilers. Particularly in such design applications, the temperature of the thermal transfer fluid exiting the furnace is highest at the center as it impinges on the upper tube sheet and enters the heat exchanger tubes closest to the centerline, and coolest near the walls of the furnace as it impinges on the top tube sheet and enters the heat exchanger tubes along the circumference. In such applications, avoiding high temperatures near the centerline that can cause boiling of the production fluid and material failure is an important limiting design constraint.

It has also been unexpectedly discovered that radial flow of production fluid through the collection of heat exchanger tubes is effective at promoting a uniform, distribution of temperature and flow velocity within the heat exchanger. Radial flow of the production fluid can be arranged by design in a fluid heating system using arrangements of baffles that cause the flow to alternate between inward-directed radial flow towards the longitudinal axis and outward-directed radial flow towards the pressure vessel inner wall. Additionally, the geometry of alternating radial flows ensures that peak velocities occur at the center of the tube bundle, where they are most needed, as confirmed by computational fluid dynamic (CFD) modeling simulation.

Furthermore, it has been unexpectedly discovered that sealing the baffles to the heat exchanger tubes and the pressure vessel inner surface substantially contribute to the creation of a uniform temperature and velocity production fluid flow field. Sealing the heat exchanger tubes to the baffles eliminates gaps where production fluid can leak through a baffle, degrading the desired radial flow and creating regions where low flow velocities and high temperatures can concentrate. The disclosed configuration provides unexpectedly improved uniformity in the production fluid velocity and temperature field.

An embodiment of a baffle assembly promoting uniform production flow conditions is shown in FIG. 2, the assembly comprising an upper tube sheet 105A, a lower tube sheet 110A, and a heat exchanger tube 115B, which connects the upper tube sheet and the lower tube sheet. A baffle assembly 220 is disposed between the upper tube sheet and the lower tube sheet, wherein the heat exchanger tube sealingly passes through the baffle 250. The baffle assembly is secured to the pressure vessel using a mounting flange 245.

As used herein, “sealingly” means that a seal is provided between adjacent members (such as a heat exchanger tube and a baffle; or an annular baffle and the pressure vessel) to substantially or effectively preclude fluid flow between the adjacent members. Specifically, sealingly disposed means that the seal provided between two members allows for less than or equal to 10 volume percent (vol %), or 0 to 10 vol %, or 0 to 5 vol %, or 0 to 1 vol %, or 0 to 0.1 vol %, or 0 to 0.01 vol %, or 0 to 0.001 vol %, or 0 to 0.0001 vol % of the total fluid flow traversing the baffle, to flow between the two members. For example, the seal can be formed merely from the close proximity of the adjacent members or the seal can be formed, for example, using a gasket or a weld. In an embodiment, a region between the adjacent members is 80% to 100%, 90% to 99%, or 95% to 98% obscured, and preferably 95% to 100% obscured, wherein the foregoing percentage is determined as a percentage of the area between the adjacent members.

As shown in FIG. 3, the plate baffle 225A may be in the shape of a plate with a perimeter having any suitable geometry. The plate may be rectilinear or curvilinear, and may have a disk shape, an elliptical shape, a lobular shape, a square shape, a rectangular shape, or any combination thereof. Each heat exchanger tube passes through a hole 300 in the plate baffle. The baffle assembly may be secured to the pressure vessel using a fastener that passes through a hole 310 in a mounting flange 245A.

The components comprising the baffle assembly may each independently comprise any suitable material, and may comprise a metal such as iron, aluminum, magnesium, titanium, nickel, cobalt, zinc, silver, copper, an alloy comprising at least one of the foregoing, or a combination thereof. Representative metals include carbon steel, mild steel, cast iron, wrought iron, stainless steel (e.g., 304, 316, or 439 stainless steel), Monel, Inconel, bronze, and brass. Specifically mentioned is an embodiment in which the baffle assembly components are mild steel.

The plate baffle assembly is sealed to the heat exchanger tubes to prevent production fluid flow in the gap between the baffle and the tubes, thereby forcing the fluid across the perimeter of the baffle assembly. The baffle assembly may be sealed to the heat exchanger tubes using any suitable method, for example by welding the heat exchanger tubes to the plate baffle, or sealing the gap using an adhesive.

In another embodiment, the plate baffle may be sealed to the heat exchanger tubes using a gasket, as shown in FIG. 4. In this embodiment, the plate baffle assembly comprises a rigid plate baffle element 225B, and a gasket 230A is disposed on a surface of the plate baffle and between the rigid element and the heat exchanger tube, wherein the gasket seals the baffle to the heat exchanger tube where the heat exchanger tube passes through the baffle. The gasket may be secured to the plate baffle using an adhesive. A retainer 235A may also be used to secure the retainer to the plate baffle using adhesive or fasteners 240A. Any suitable adhesive may be used. Representative adhesives include a vinyl ester, an epoxy, a phenolic, a silicone, a polyurethane, and a fluorinated rubber.

The gasket used to seal the baffle to the heat exchanger tubes may comprise an elastomer. Specifically mentioned is an embodiment where the elastomer is an ethylene propylene diene terpolymer.

An embodiment of the plate baffle assembly incorporating a gasket and a retainer is shown in FIG. 5, where the gasket 230B is disposed between the plate baffle 225C and the retainer 235B. In the embodiment shown in FIG. 5, the retainer outer diameter is smaller than the plate baffle diameter so that the gasket protrudes 515 from the baffle assembly and contacts the outer wall of the heat exchanger tube 505, preferentially in the direction of the retainer. As a result, fluid pressure forces the gasket against the heat exchanger tube outer wall, promoting the seal. The shape of the plate baffle and the seal between the baffle and the heat exchanger tube forces the production fluid to flow across the perimeter of the baffle assembly, between the edge of the baffle assembly and the inner surface of the pressure vessel 150A.

As a result, the plate baffle assembly forces the production fluid to flow radially, outward from the longitudinal centerline of the heat exchanger and around the perimeter of the baffle.

Another embodiment of a baffle assembly promoting uniform production flow conditions is shown in FIG. 6, the baffle assembly comprising a pressure vessel 150B and an annular baffle assembly 630. The baffle assembly is sealingly disposed in the pressure vessel, the sealed baffle assembly comprising an upper tube sheet 105B; a lower tube sheet 110B opposite the upper tube sheet; a heat exchanger tube 115C which connects the upper tube sheet and the second tube sheet; an annular baffle 615 disposed between the first tube sheet and the second tube sheet, wherein the heat exchanger tube passes through the annular baffle, the annular baffle has a first side and an opposite second side, and the annular baffle has an annular shape, wherein the sealed baffle assembly is sealingly disposed in the pressure vessel such that least 51% of fluid communication between the first side and the second side of the baffle is through the center region bounded by the inner diameter of the baffle annulus.

As shown in FIG. 7, the annular baffle 610A may be in the shape of an annulus with an inner perimeter 700 and outer perimeter 701. The inner diameter 700 and outer perimeter 701 can each independently have any suitable geometry, can be a rectilinear or curvilinear, and can have a circular shape, an elliptical shape, a lobular shape, a square shape, a rectangular shape, or any combination thereof. The heat exchanger tube passes through a hole 710 in the annular baffle. The baffle assembly may be secured to the pressure vessel using a fastener that passes through the hole 715 and is secured to a mounting flange on the pressure vessel wall.

The circumference of the annular baffles is designed to be disposed on the inner surface of the pressure vessel and may be sealed by a weld or gasket or unsealed and mounted to the pressure vessel at attachment points. The annular opening is a major factor in specifying the fluid pressure drop in that heat exchanger section. It has been discovered that the size of the annulus can be chosen so that the first 1-3 inner rows of heat exchanger tubes pass through the annulus. Thus the dimensions of the annulus can be determined by the pressure drop characteristics of the flow through the annulus, and not a fixed fraction of the baffle surface. For plate baffles, the diameter is typically selected so that the outermost tube row sealingly passes through the plate baffle.

The components comprising the annular baffle assembly may each independently comprise any suitable material, and may comprise a metal such as iron, aluminum, magnesium, titanium, nickel, cobalt, zinc, silver, copper, and an alloy comprising at least one of the foregoing. Representative metals include carbon steel, mild steel, cast iron, wrought iron, stainless steel (e.g., 304, 316 or 439 stainless steel), Monel, Inconel, bronze, and brass. Specifically mentioned is an embodiment in which the baffle assembly components are mild steel.

The annular baffle assembly is sealed to the inner surface of the pressure vessel to prevent production fluid flow in the gap between the annular baffle and the pressure vessel, thereby forcing the fluid across the inner perimeter of the baffle assembly and through the center region bounded by the inner diameter of the baffle annulus. The baffle assembly may be sealed to the pressure vessel in any suitable way, including welding the annular baffle to the pressure vessel inner surface, or sealing the gap using an adhesive.

In another embodiment, the annular baffle may be sealed to the inner surface of the pressure vessel using a gasket, as shown in FIG. 8. In this embodiment, the annular baffle assembly comprises a rigid annular baffle element 610A, and a gasket 615A is disposed on a surface of the annular baffle and between the baffle and the pressure vessel 150B, wherein the gasket seals the baffle to the pressure vessel. The gasket may be secured to the annular baffle using an adhesive. A retainer 620A may also be used to secure the retainer to the annular baffle using adhesive or fasteners.

The gasket used to seal the baffle to the heat exchanger tubes may comprise an elastomer. Any suitable elastomer may be used. Specifically mentioned is an embodiment where the elastomer is an ethylene propylene diene terpolymer.

An embodiment of the annular baffle assembly incorporating a gasket and retainer is further shown in FIG. 8 where the gasket 615A is disposed between the annular baffle 610A and the retainer 620A. The retainer outer diameter is smaller than the plate baffle diameter so that the gasket protrudes 810 from the baffle assembly and contacts the inner wall of the pressure vessel 150B, preferentially in the direction of the retainer. As a result, fluid pressure forces the gasket against the pressure vessel inner wall, promoting the seal. The shape of the annular baffle and the seal between the baffle and the pressure vessel forces the production fluid to flow across the inner perimeter of the baffle assembly annulus through the center region bounded by the inner diameter of the baffle annulus.

The annular baffle assembly may further be sealed to the heat exchanger tubes to prevent production fluid flow in the gap between the baffle and the tubes, thereby forcing the fluid across the inner perimeter of the annular baffle assembly. The baffle assembly may be sealed to the heat exchanger tubes in a variety of ways including welding the heat exchanger tubes to the annular baffle, or sealing the gap using an adhesive.

An embodiment of the annular baffle assembly incorporating a gasket and a retainer to further seal the baffle to the heat exchanger tubes is also shown in FIG. 8, where the gasket 615A is disposed between the annular baffle 610A and the retainer 620A. The retainer outer diameter is smaller than the annular baffle diameter so that the gasket protrudes 800 from the baffle assembly and contacts the outer wall of the heat exchanger tube 505A, preferentially in the direction of the retainer. As a result, fluid pressure forces the gasket against the heat exchanger tube outer wall, promoting the seal. The shape of the annular baffle and the seal between the baffle and the heat exchanger tube further forces the production fluid to flow across the inner perimeter of the baffle assembly annulus through the center region bounded by the inner diameter of the baffle annulus.

As a result, the annular baffle assembly forces the production fluid to flow radially, inward towards the longitudinal centerline of the heat exchanger and through the center region bounded by the inner diameter of the baffle annulus.

An another embodiment, the plate and annular baffle assembly can be used in conjunction to maintain a predominately radial flow pattern in the production fluid along the length of the fluid heating system heat exchanger.

FIG. 9 shows an embodiment of a fluid heating system sealed baffle assembly comprising: an upper tube sheet 205B; a lower tube sheet 210B opposite the upper tube sheet; a heat exchanger tube 115D, which connects the upper tube sheet and the lower tube sheet; and a plate baffle assembly 220A disposed between the upper tube sheet and the lower tube sheet, wherein the heat exchanger tube sealingly passes through the plate baffle assembly; and an annular baffle assembly 630A disposed between the upper tube sheet and the lower tube sheet, wherein the heat exchanger tube sealingly passes through the annular baffle.

An embodiment where the plate and annular baffles alternate along the length of the heat exchanger is further shown in FIG. 10. In this embodiment three annular baffles 630B alternate with two plate baffles 220B. The heat exchanger tubes sealingly pass through both types of baffles, and the annular baffles are sealed to the pressure vessel inner surface (not shown).

The flow pattern induced by the alternating plate and annular baffles is illustrated in the rendering shown in FIG. 11, where production fluid entering the inlet 1100 flows through the center region of the first annular baffle assembly 1105, turns outward and flows radially 1110 to the outer perimeter of the first plate baffle assembly 1120 where it is turned inward to again flow radially to the center region of the second annular baffle assembly 1130. This alternating radial flow pattern continues until the production fluid passes through the outlet (not shown) and out of the pressure vessel.

The selection of the number of baffles, and the spacing between them is highly dependent on the performance and fluid desired for the product. The measure of optimality for this design process can be stated as: minimizing the fluid side pressure drop as the fluid moves from pressure vessel inlet to the outlet (subject to operational constraints, where larger pressure drops result in larger pumping requirements and overall reduction in system efficiencies once installed), while simultaneously minimizing the number and magnitude of local tube temperature outliers, subject to a given threshold temperature. Most often the temperature threshold selected is the vaporization temperature for the given fluid, at the given operating pressure, but can be selected based on any number of measures, durability or otherwise, including but not limited to material temperature limits, production fluid temperature limits, thermal stress limits, or any other suitable measure.

Variables important for the optimization of the baffle spacing, attachment and design geometry are many including, but not limited to: the production fluid viscosity, boiling point, density, specific heat, and thermal conductivity; the heat exchanger tube geometry, heat exchanger tube material; and the pressure drop constraints. Also important is the design flow rate of production fluid from the pressure vessel inlet to outlet which is often specified by a temperature change from the inlet to outlet, at a given heat input.

Standard heat exchanger design references recommend the minimum spacing between the baffles be 20% of the shell diameter. (Shah, Ramesh K., and Dusan P. Sekulic. “Fundamentals of heat exchanger design”, John Wiley & Sons, 2003.) In products with high heat flux, the flow velocity may be insufficient to keep the metals temperatures below the production fluid boiling temperature which creates an important constraint. Reducing the baffle separation distance does not solve the problem since the pressure gradient promotes the leakage flow rather than the main cross flow. Sealing the baffle provides an approach to exceed conventional design limits since it enables flow velocities and heat transfer coefficients required to avoid local boiling temperatures without the leakage side effects.

In an embodiment wherein the production fluid is a liquid (e.g., water, thermal fluid or thermal oil), the temperature difference between the pressure vessel inlet and outlet can be between 180 degrees centigrade (° C.), or 170° C., or 160° C., or 150° C., or 140° C., or 130° C., or 120° C., or 110° C., or 105° C., or 100° C., or 95° C., or 90° C., or 85° C., or 80° C., or 75° C., or 70° C., or 65° C., or 60° C., or 55° C., or 50° C., or 45° C., or 40° C., or 35° C., or 30° C., or 25° C., or 20° C., or 15° C., or 10° C. The temperature difference range 110° C. to 30° C. is specifically mentioned. Depending upon the geometric, thermal, fluid and material properties of the embodiment, the separation distance between baffle plates may be between 300 centimeters (cm), or 250 cm, or 200 cm, or 150 cm, or 100 cm, or 90 cm, or 80 cm, or 70 cm, or 60 cm, or 50 cm, or 40 cm, or 35 cm, or 30 cm, or 26 cm, or 24 cm, or 22 cm, or 20 cm, or 18 cm, or 16 cm, or 14 cm, or 12 cm, or 10 cm, or 8 cm to 6 cm, or 5 cm, or 4 cm, or 3 cm, or 2 cm, or 1.5 cm, or 1 cm, or 0.5 cm or 0.25 cm, wherein the foregoing upper and lower bounds can be independently combined. The gap distance range from 1.5 cm to 50 cm is specifically mentioned.

An optimum spacing can be determined for combinations of design variables and fluid properties. Computation Fluid Dynamic (CFD) numerical simulation can be used to design the baffle system and, in particular, the spacing between the baffle plates accounting for each of the design variables. For instance, a baffle set designed for a hydronic fluid heating systems with a 20 degrees Fahrenheit (° F.) temperature difference between the pressure vessel inlet and outlet, will have significantly different optimal spacing requirements than one designed for a 40° F. temperature difference, where the production fluid is glycol or a combined glycol and water mixture.

However, it has been unexpectedly discovered that the baffles can be arranged where the baffles are sealed to the tubes, or where the baffles are unsealed, with similar results at the beginning of life. Where the baffles are unsealed, the small amount of leakage flow where the heat exchanger tubes pass through the baffle holes acts to break up vortices and stagnant flow areas, whereas if the baffles are sealed, more baffles are required to ensure these areas of low, or cyclical flow are managed so as not to cause a durability issue.

Also surprising is the discovery that unsealed baffles have radically different performance characteristics over their life span. Specifically, the result can be a solution, which is indeterminate with respect to time. In other words, the system can be designed such that extreme changes in performance and symmetry can present themselves over time during the systems life in the field. Once a radial flow pattern has been selected, the system is inherently designed with a high degree of axial symmetry. During system operation, small amounts of debris tend to get caught in the gap between the baffle and the tube and corrosion material will build-up over time. A loss of leakage flow through a given baffle to tube space is irrelevant in a local sense; however, as the debris does not deposit symmetrically around the axis, the blocked local leakage flow can have a major impact on the flow symmetry which has a significant effect downstream in the heat exchanger.

While the effects of symmetry on the dynamics and stability of fluid flow systems has been considered in other engineering fields, the study of fluid flow in a heat exchanger is particularly complex. In the case of unsealed baffles, when the flow symmetry surrounding the tubes and around the circumference of the plate baffles is broken where debris or corrosion material clogs the gaps, the production fluid flow is disrupted causing a new flow field and resulting temperature distribution. The perturbations in the flow and temperature fields can be dramatic, even for small changes in the geometry caused by particulate clogging of the gaps. In fact, this sensitive dependence upon flow conditions were observed during instrumented prototype testing where a single test rig would exhibit significantly different temperature field behavior from test to test as debris accumulated and sifted in the unsealed gaps. This sensitive dependence on the precise geometry of the gaps was eliminated by sealing.

As is discussed above, an advantage of the disclosed system is that it can provide a more uniform production fluid flow field which is predominately radial, minimizing areas of high temperature that are understood to cause material failures, fluid boiling, and loss of thermal efficiency. The disclosed baffle assembly and heat exchanger provides for improvement in the management of production fluid flow of fluid heating systems and heat exchangers that enable greater compactness, reliability and performance in these systems.

Presented below are non-limiting examples of the present disclosure.

EXAMPLES
Example 1

Two fluid heating systems with alternating annular and plate baffles configurations were constructed and instrumented based on the embodiment illustrated in FIG. 9 for the purpose of comparing the advantages of sealing the baffles to the heat exchanger tubes and pressure vessel compared to leaving these areas unseal and allowing flow the gaps formed between these structures.

The first of the two fluid heating test systems comprises a heat exchanger with five baffle plates and 275 heat exchanger tubes in a boiler that is supplied with a heat input of 3 million BTU/hr. The production fluids tested were water and various mixtures of water and glycol. The gaps formed between the openings in the baffles where the heat exchanger tubes penetrate the baffles were between 0.0 cm (contact surfaces) and 0.5 cm and were unsealed, allowing a flow of production fluid through the gaps.

The first (unsealed) fluid heating test system was instrumented with thermocouples at various positions in each region, T₂through T₅shown in FIG. 9, between the set of five baffles to measure the evolution of production fluid temperatures over time as the test units were operated under installed conditions. The system was operated under normal installation conditions for 118 days and the temperatures at each of the measurement points was recorded at the beginning and end of the test period. The second and third columns of TABLE 1 show the results. For each fluid region, the average of the temperature difference range from the beginning to the end of the test period is shown, together with the standard deviation of the temperature ranges measured. These data provide a measurement of the average temperature deviation of the test period together with the variance of the temperature deviations. These data show large variations in the temperature measurements over the test period, due to the accumulation of debris and corrosion in the unsealed gaps between the baffles and heat exchanger tubes which changes the production fluid flow pattern over (relatively short) time periods away from the target design conditions.

The second of the two fluid heating test systems comprises a heat exchanger with seven baffle plates and 275 heat exchanger tubes in a system configuration that is supplied with a heat input of 3 million BTU/hr. A view of the heat exchanger is shown in FIG. 12 with the pressure vessel removed where a plate baffle assembly 1200 and an annular baffle assembly 1210 is visible. Heat exchanger tubes pass through the alternating sequence of plate and annular baffles assemblies, sealed by gaskets and held in place by retainers as shown in FIG. 8. The production fluids tested were water and various mixtures of water and glycol. The gaps formed between the openings in the baffles where the heat exchanger tubes penetrate the baffles were between 0 cm (contact surfaces) and 0.3 cm and were sealed, preventing the flow of production fluid through the baffle plates where the heat exchanger tubes sealingly pass through the baffles.

The second (sealed) fluid heating test system was instrumented with thermocouples at various positions in each region, T₂through T₅shown in FIG. 9, between the set of seven baffles to measure the evolution of production fluid temperatures over time as the test units were operated under installed conditions. The system was operated under normal installation conditions for 16 days and the temperatures at each of the measurement points was recorded at the beginning and end of the test period. The fourth and fifth columns of TABLE 1 show the results. For each fluid region, the average of the temperature difference range from the beginning to the end of the test period is shown, together with the standard deviation of the temperature ranges measured. These data provide a measurement of the average temperature deviation of the test period together with the variance of the temperature deviations. These data reduced variations in the temperature measurements over the test period, since debris and corrosion can no longer accumulate in the gaps between the baffles and heat exchanger tubes. As a result, the production fluid flow pattern over is stabilized at or near the target design conditions.

TABLE 1

Fluid Heating
Fluid Heating

Test System 1
Test System 2

(Unsealed Gaps)
(Sealed Gaps)

Average
Std. Dev. Of
Average
Std. Dev.

Test
Temp
Temp
Temp
Of Temp

Region
Range (° F.)
Range (° F.)
Range (° F.)
Range (° F.)

T₂
4.8
2.0
2.9
1.8

T₃
21.3
13.4
3.4
1.2

T₄
15.2
6.9
6.4
4.3

T₅
7.0
3.9
11.5
8.5

Example 2

A computational fluid dynamics (CFD) simulation of the fluid heating system prototype shown in FIG. 12 was performed.

Operating Conditions:

Input:
3,000,000 BTU/hr (878.4 kW)

Inlet Temperature:
80° F. (26.6° C.)

Outlet Temperature:
180° F. (82.2° C.)

Geometry:

Tube Length:
40
inches (1.016m)

Tube Outside Diameter:
0.5
inches (12.7e−3m)

Number of Tubes
275

Inlet Inside Diameter:
4
inches (1.016e−1m)

Pressure Vessel Inside Diameter:
23.5
inches (5.969e−1m)

Baffle Spacing:
2, 5, 8, 8, 8, 9
inches

Plate Baffle Diameter:
19 5/8
inches (4.985e−1m)

Annular Baffle Inside Diameter:
6 1/8
in (1.555e−1m)

(Annulus Outside Diameter Equals

Pressure Vessel Shell Inside

Diameter)

FIG. 13 shows the nearly uniform flow field generated by the alternating sequence of plate and annular baffles.

Example 3

A computational fluid dynamics (CFD) simulation of the fluid heating system prototype shown in FIG. 12 was performed.

Operating Conditions:

Input:
3,000,000 BTU/hr (878.4 kW)

Inlet Temperature:
80° F. (26.6° C.)

Outlet Temperature:
120° F. (48.9° C.)

In this simulation, the separation distance between the heat exchanger top sheet and the first baffle plate (forming the region T₁in FIG. 9) was varied to illustrate the changes in production flow field uniformity as a function of baffle separation distance.

In FIG. 14A the separation between the top sheet and the first baffle was 0.75 inches. At this separation distance and these simulated operating conditions, the flow field shows a pronounced region of reduced flow velocity near the centerline 1405. FIG. 14B shows a simulation with the same geometry and operating conditions, but the separation between the top sheet and the first baffle has been increased to 1.25 inches. At this increased separation distance, the flow field is more uniform including the flow velocity near the centerline 1415. A design objective is to minimize the separation distance while achieving a relatively uniform flow field across the face of the baffle. In many cases the uniformity of flow must be weighed against the specific temperature needs of the tubes in that flow region. As a result, either spacing could be considered “optimal” pending the specific case in question.

An embodiment is disclosed with a baffle assembly comprising: a first tube sheet; a second tube sheet opposite the first sheet; a heat exchanger tube, which connects the first tube sheet and the second tube sheet; and a baffle disposed between the first tube sheet and the second tube sheet, wherein the heat exchanger tube sealingly passes through the baffle; wherein the baffle is a plate baffle, and wherein the plate baffle has a disk shape, an elliptical shape, a lobular shape, a square shape, a rectangular shape, a rectilinear shape, or a curvilinear shape, or any combination thereof; wherein the baffle has a disk shape; wherein the baffle has a first side and an opposite second side, and wherein fluid communication between the first side and the second side is exclusively across a perimeter of the baffle; wherein a maximum distance between an outer surface of the heat exchanger tube and the baffle is between 0 centimeters and 3 centimeters; further comprising a continuous weld, which sealingly connects the baffle to the heat exchanger tube; wherein the continuous weld which sealingly connects the baffle to the heat exchanger tube is disposed on a circumference of the tube; further comprising an adhesive, which adhesively and sealingly connects the baffle to the heat exchanger tube, and wherein the adhesive is disposed between the heat exchanger tube passes and the baffle; wherein the baffle comprises a rigid element, and a gasket disposed on a surface of the rigid element and between the rigid element and the heat exchanger tube, wherein the gasket seals the baffle to the heat exchanger tube where the heat exchanger tube passes through the baffle; wherein the gasket is attached to the rigid element by an adhesive; further comprising a retainer, which is attached to the rigid element by a fastener, and wherein the gasket is disposed between the rigid element and the retainer; wherein the gasket comprises an elastomer; wherein the elastomer is ethylene propylene diene monomer; wherein the gasket comprises a metal plate with a maximum thickness between 0.002 millimeters to 6 millimeters; wherein the sealed baffle assembly comprises a plurality of heat exchanger tubes, and wherein each heat exchanger tube independently sealingly penetrates the baffle; wherein the plurality of heat exchanger tubes comprises 50 to 5000 heat exchanger tubes; wherein the sealed baffle assembly comprises a plurality of baffles, and wherein each heat exchanger tube sealingly penetrates each baffle; wherein the plurality of baffles comprises 3 to 100 baffles; wherein the baffle has an aspect ratio of 5 to 10,000, wherein the aspect ratio is a largest dimension of a major surface of the baffle divided by a thickness of the baffle.

Set forth below are non-limiting embodiments of the present disclosure.

Embodiment 1: A baffle assembly comprising: a first tube sheet; a second tube sheet opposite the first sheet; a heat exchanger tube, which connects the first tube sheet and the second tube sheet; and a baffle disposed between the first tube sheet and the second tube sheet, wherein the heat exchanger tube passes through the baffle, optionally, wherein the heat exchanger tube sealingly passes through the baffle.

Embodiment 2: The baffle assembly of embodiment 1, wherein the baffle has a disk shape, an elliptical shape, a lobular shape, a square shape, a rectangular shape, a rectilinear shape, or a curvilinear shape, or any combination thereof.

Embodiment 3: The baffle assembly of any of embodiments 1 or 2, wherein the baffle has a disk shape.

Embodiment 4: The baffle assembly of any of embodiments 1 to 3, wherein the baffle comprises a plate baffle that has a first side and an opposite second side, and wherein fluid communication between the first side and the second side is across a perimeter of the baffle. At least 51%, or at least 90%, or at least 99% by weight of fluid communication between the first side and the second side of the baffle can be through the perimeter of the baffle.

Embodiment 5: The baffle assembly of any of embodiments 1 to 4, wherein the baffle comprises an annular baffle that has a first side and an opposite second side, and wherein fluid communication between the first side and the second side is across an annulus of the baffle. At least 51%, or at least 90%, or at least 99% by weight of fluid communication between the first side and the second side of the baffle can be through the annulus of the annular baffle.

Embodiment 6: The baffle assembly of any of embodiments 1 to 5, wherein a maximum distance between an outer surface of the heat exchanger tube and the baffle is between 0 centimeters and 3 centimeters.

Embodiment 7: The baffle assembly of any of embodiments 1 to 6, further comprising a continuous weld, which sealingly connects the baffle to the heat exchanger tube; or wherein a seal is formed between the heat exchanger tubes and the baffle based on a close proximity of the heat exchanger tubes and the baffle.

Embodiment 8: The baffle assembly of embodiment 7, further comprising the weld; wherein the continuous weld which sealingly connects the baffle to the heat exchanger tube is disposed on a circumference of the tube.

Embodiment 9: The baffle assembly of any of embodiments 1 to 8, further comprising an adhesive, which adhesively and sealingly connects the baffle to the heat exchanger tube, and wherein the adhesive is disposed between the heat exchanger tube passes and the baffle.

Embodiment 10: The baffle assembly of any of embodiments 1 to 9, wherein the baffle comprises a rigid element, and a gasket disposed on a surface of the rigid element and between the rigid element and the heat exchanger tube, wherein the gasket seals the baffle to the heat exchanger tube where the heat exchanger tube passes through the baffle.

Embodiment 11: The baffle assembly of embodiment 10, wherein the gasket is attached to the rigid element by an adhesive.

Embodiment 12: The baffle assembly of any of embodiments 10 to 11, further comprising a retainer, which is attached to the rigid element by a fastener, and wherein the gasket is disposed between the rigid element and the retainer.

Embodiment 13: The baffle assembly of any of embodiments 10 to 12, wherein the gasket comprises an elastomer.

Embodiment 14: The baffle assembly of any of embodiments 10 to 13, wherein the elastomer is ethylene propylene diene monomer.

Embodiment 15: The baffle assembly of any of embodiments 10 to 14, wherein the gasket comprises a metal plate with a maximum thickness between 0.002 millimeters to 6 millimeters.

Embodiment 16: The baffle assembly of any of embodiments 1 to 15, wherein the baffle assembly comprises a plurality of heat exchanger tubes, and wherein each heat exchanger tube independently sealingly penetrates the baffle.

Embodiment 17: The baffle assembly of any of embodiments 1 to 16, wherein the plurality of heat exchanger tubes comprises 50 to 5000 heat exchanger tubes.

Embodiment 18: The baffle assembly of any of embodiments 1 to 17, wherein the baffle assembly comprises a plurality of baffles, and wherein each heat exchanger tube sealingly penetrates each baffle.

Embodiment 19: The baffle assembly of any of embodiments 1 to 18, wherein the plurality of baffles comprises 3 to 100 baffles.

Embodiment 20: The baffle assembly of any of embodiments 1 to 19, wherein the baffle has an aspect ratio of 5 to 10,000, wherein the aspect ratio is a largest dimension of a major surface of the baffle divided by a thickness of the baffle.

Embodiment 21: The baffle assembly of any one of embodiments 1-20, wherein the baffle assembly comprises a plurality of baffles comprising at least one plate baffle and at least one annular baffle.

Embodiment 22: The baffle assembly of any one of embodiments 1 to 21, wherein a fluid flow through the baffle assembly encounters an alternating route of plate baffles and annular baffles.

Embodiment 23: A heat exchanger comprising: a pressure vessel; and a baffle assembly disposed in the pressure vessel such as the one described in any one of embodiments 1 to 22, the baffle assembly comprising a first tube sheet, a second tube sheet opposite the first tube sheet, a heat exchanger tube, which connects the first tube sheet and the second tube sheet, a baffle disposed between the first tube sheet and the second tube sheet, wherein the heat exchanger tube passes through the baffle.

Embodiment 24: The heat exchanger of embodiment 23, wherein a maximum distance between an inner surface of the pressure vessel and an edge surface of the baffle is between 0 centimeters and 3 centimeters.

Embodiment 25: The heat exchanger of any of embodiments 23 to 24, further comprising a continuous weld, which sealingly connects the annular baffle to the pressure vessel.

Embodiment 26: The heat exchanger of any of embodiments 23 to 25, wherein the continuous weld which sealingly connects the annular baffle to the heat exchanger tube is disposed on a perimeter of the baffle.

Embodiment 27: The heat exchanger of any of embodiments 23 to 26, further comprising an adhesive, which adhesively and sealingly connects the baffle to the pressure vessel, and wherein the adhesive is disposed on the perimeter of the baffle.

Embodiment 28: The heat exchanger of any of embodiments 23 to 27, wherein the baffle comprises a rigid element, and a gasket disposed on the surface of the rigid element, wherein the gasket seals the annular baffle to the pressure vessel on the perimeter of the annular baffle.

Embodiment 29: The heat exchanger of embodiment 28, wherein the gasket is attached to the rigid element by an adhesive.

Embodiment 30: The heat exchanger of any of embodiments 28 to 29, further comprising a retainer, which is attached to the rigid element by a fastener, and wherein the gasket is disposed between the rigid element and the retainer.

Embodiment 31: The heat exchanger of any of embodiments 28 to 30, wherein the gasket comprises an elastomer.

Embodiment 32: The heat exchanger of embodiment 31, wherein the elastomer is ethylene propylene diene monomer.

Embodiment 33: The heat exchanger of any of embodiments 28 to 32, wherein the gasket comprises a metal plate having a maximum thickness between 0.002 millimeters to 6.35 millimeters.

Embodiment 34: The heat exchanger of any of embodiments 23 to 33, wherein the heat exchanger tube sealingly passes through the baffle, wherein the baffle comprises an annular baffle, and wherein fluid communication between the first side and the second side of the annular baffle is through the annulus of the baffle, for example, exclusively across.

Embodiment 35: The heat exchanger of any of embodiments 23 to 34, wherein the heat exchanger tube sealingly passes through the baffle, wherein the baffle comprises a plate baffle, and wherein fluid communication between the first side and the second side of the plate baffle is across the perimeter of the baffle, for example, exclusively across.

Embodiment 36: The heat exchanger of any of embodiments 23 to 35, wherein a maximum distance between an outer surface of the heat exchanger tube and the baffle is between 0 centimeters and 3 centimeters.

Embodiment 37: The heat exchanger of any of embodiments 23 to 36, further comprising a continuous weld, which sealingly connects the baffle to the heat exchanger tube.

Embodiment 38: The heat exchanger of any of embodiments 23 to 37, wherein the continuous weld which sealingly connects the baffle to the heat exchanger tube is disposed on a circumference of the tube.

Embodiment 39: The heat exchanger of any of embodiments 23 to 38, further comprising an adhesive, which adhesively and sealingly connects the baffle to the heat exchanger tube, wherein the adhesive is disposed between the heat exchanger tube and the baffle where the heat exchanger tube passes through the baffle.

Embodiment 40: The heat exchanger of any of embodiments 23 to 39, wherein the baffle comprises a rigid element, and a gasket disposed on the surface of the rigid element, wherein the gasket seals the baffle to the heat exchanger tube where the heat exchanger tube passes through the baffle, and wherein the gasket seals the baffle to the pressure vessel on the perimeter of the baffle.

Embodiment 41: The heat exchanger of embodiment 40, wherein the gasket is attached to the rigid element by the adhesive.

Embodiment 42: The heat exchanger of any of embodiments 40 to 41, further comprising a retainer, which is attached to the rigid element by a fastener, and wherein the gasket is disposed between the rigid element and the retainer.

Embodiment 43: The heat exchanger of any of embodiments 40 to 42, wherein the gasket comprises an elastomer.

Embodiment 44: The heat exchanger of any of embodiments 40 to 43, wherein the elastomer is ethylene propylene diene monomer.

Embodiment 45: The heat exchanger of any of embodiments 40 to 44, wherein the gasket comprises a metal plate having a maximum thickness between 0.002 millimeters to 6 millimeters.

Embodiment 46: The heat exchanger of any of embodiments 23 to 45, wherein the heat exchanger assembly comprises a plurality of heat exchanger tubes, and wherein each heat exchanger tube independently and penetrates the baffle.

Embodiment 47: The heat exchanger of embodiment 46, wherein the plurality of heat exchanger tubes comprises 50 to 5000 heat exchanger tubes.

Embodiment 48: The heat exchanger of embodiments 23 to 47, comprising a plurality of annular baffles and/or plate baffles, wherein each baffle is sealingly disposed between the first tube sheet and the second tube sheet.

Embodiment 49: The heat exchanger of any of embodiments 23 to 48, wherein the heat exchanger comprises a plurality of annular baffles and/or plate baffles, and wherein each heat exchanger tube penetrates each baffle.

Embodiment 50: The heat exchanger of any of embodiments 23 to 49, wherein the plurality of baffles comprises 3 to 100 baffles.

Embodiment 51: The baffle assembly or the heat exchanger of any of the preceding embodiments, wherein a seal is formed between the baffle and the heat exchanger tube based solely on a close proximity to each other.

Embodiment 52: The baffle assembly or the heat exchanger of any of the preceding embodiments, wherein a region between the baffle and the heat exchanger tube is 80% to 100% obscured, wherein the foregoing percentage is determined as a percentage of the area between the baffle and the heat exchanger tube.

Embodiment 53: The baffle assembly or the heat exchanger of any of the preceding embodiments, wherein a tube seal provided between the heat exchanger tube and the baffle allows for less than or equal to 10 vol % of a total fluid flow traversing the baffle, to flow between them and/or wherein a vessel seal provided between the pressure vessel and an annular baffle allows for less than or equal to 10 vol % of a total fluid flow traversing the baffle, to flow between them.

Embodiment 54: A baffle assembly, such as any one of the preceding embodiments, comprising: a first tube sheet; a second tube sheet opposite the first sheet; a heat exchanger tube, which connects the first tube sheet and the second tube sheet; and a plate baffle disposed between the first tube sheet and the second tube sheet, wherein the heat exchanger tube sealingly passes through the plate baffle, and an annular baffle sealingly disposed between the first tube sheet and the second tube sheet, wherein the heat exchanger tube sealingly passes through the annular baffle.

Embodiment 55: The baffle assembly of embodiment 54, wherein the plate baffles and the annular baffles alternate from the first tube sheet to the second tube sheet.

Embodiment 56: The baffle assembly of any of embodiments 1 to 55, wherein a separation distance between adjacent baffles is between 0.2 centimeters and 5,200 centimeters.

Embodiment 57: The baffle assembly of any of embodiments 1 to 56, wherein the heat exchanger tube has a first end and an opposite second end, wherein the first end of the heat exchanger tube is disposed on the first tube sheet, and wherein the second end of the heat exchanger tube is disposed on the second tube sheet, wherein a perimeter of the first end of the heat exchanger tube is sealingly connected to the first tube sheet, and wherein a perimeter of the second end of the heat exchanger tube is sealingly connected to the second tube sheet.

Embodiment 58: A method of producing radial flow in a heat exchanger, the method comprising: providing a heat exchanger comprising a baffle assembly, such as that of any one of embodiments 1-57, comprising a pressure vessel shell comprising an inlet and outlet, a baffle assembly entirely disposed in the pressure vessel shell, the baffle assembly comprising a first tube sheet, a second tube sheet opposite the first sheet, a heat exchanger tube, which connects the first tube sheet and the second tube sheet; and at least one plate baffle disposed between the first tube sheet and the second tube sheet, wherein the heat exchanger tube sealingly passes through the baffle; and at least one annular baffle sealingly and/or at least one plate baffle disposed between the first tube sheet and the second tube sheet, wherein the heat exchanger tube sealingly passes through the baffle; and directing a production fluid from the first inlet to the first outlet to provide a flow of the production fluid through the pressure vessel shell to produce the radial flow.

Embodiment 59: The method of embodiment 58, wherein the production fluid comprises water, a substituted or unsubstituted C1 to C30 hydrocarbon, a thermal fluid, a glycol, or a combination thereof.

The disclosure has been described with reference to the accompanying drawings, in which various embodiments are shown. This disclosure may, however, be embodied in many different forms, and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Like reference numerals refer to like elements throughout.

It will be understood that when an element is referred to as being “on” another element, it can be directly on the other element or intervening elements may be present there between. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present. Also, the element may be on an outer surface or on an inner surface of the other element, and thus “on” may be inclusive of “in” and “on.”

It will be understood that, although the terms “first,” “second,” “third,” etc. may be used herein to describe various elements, components, regions, layers, and/or sections, these elements, components, regions, layers, and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or section from another element, component, region, layer or section. Thus, “a first element,” “component,” “region,” “layer,” or “section” discussed below could be termed a second element, component, region, layer, or section without departing from the teachings herein.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms, including “at least one,” unless the content clearly indicates otherwise. “Or” means “and/or.” As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. It will be further understood that the terms “comprises” and/or “comprising,” or “includes,” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof.

Furthermore, relative terms, such as “lower” or “bottom” and “upper” or “top,” may be used herein to describe one element's relationship to another element as illustrated in the Figures. It will be understood that relative terms are intended to encompass different orientations of the device in addition to the orientation depicted in the Figures. For example, if the device in one of the figures is turned over, elements described as being on the “lower” side of other elements would then be oriented on “upper” sides of the other elements. The exemplary term “lower,” can therefore, encompasses both an orientation of “lower” and “upper,” depending on the particular orientation of the figure. Similarly, if the device in one of the figures is turned over, elements described as “below” or “beneath” other elements would then be oriented “above” the other elements. The exemplary terms “below” or “beneath” can, therefore, encompass both an orientation of above and below.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

Exemplary embodiments are described herein with reference to cross section illustrations that are schematic illustrations of idealized embodiments. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments described herein should not be construed as limited to the particular shapes of regions as illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, a region illustrated or described as flat may, typically, have rough and/or nonlinear features. Moreover, sharp angles that are illustrated may be rounded. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the precise shape of a region and are not intended to limit the scope of the present claims.

All cited patents, patent applications, and other references are incorporated herein by reference in their entirety. However, if a term in the present disclosure contradicts or conflicts with a term in the incorporated reference, the term from the present disclosure takes precedence over the conflicting term from the incorporated reference.

While particular embodiments have been described, alternatives, modifications, variations, improvements, and substantial equivalents that are or may be presently unforeseen may arise to applicants or others skilled in the art. Accordingly, the appended claims as filed and as they may be amended are intended to embrace all such alternatives, modifications variations, improvements, and substantial equivalents.

BAFFLE ASSEMBLY FOR A HEAT EXCHANGER, HEAT EXCHANGER INCLUDING THE BAFFLE ASSEMBLY, FLUID HEATING SYSTEM INCLUDING THE SAME, AND METHODS OF MANUFACTURE THEREOF

Information

Publication Number

Date Filed

Date Published

Inventors

Original Assignees

CPC

International Classifications

Abstract

Description

Claims

CROSS-REFERENCE TO RELATED APPLICATION

Provisional Applications (1)