An ejection heater for a heat recovery system in a power plant

Abstract

The present invention discloses an ejection heater for a heat recovery system of a power plant, comprising a circular shell, a converging structure, a diverging structure, an outer spiral baffle, an inner spiral baffle and an ejection hole. The outer spiral baffle is placed between the circular shell and the converging structure and the diverging structure, and the inner spiral baffle is placed inside the diverging structure. The outer spiral baffle guides steam and condensate to perform inter-wall heat exchange, and the steam after heat exchange is ejected by condensate through the ejection hole into the diverging structure for mixing, and the inner spiral baffle arranged in the diffusion structure guides condensate and steam to perform sufficient mixing and heat exchange. The present invention utilizes the outer spiral baffle to perform inter-wall heat exchange between steam and condensate, thereby reducing the irreversible loss of mixed heat exchange; the inner spiral baffle increases the turbulence of the fluid, prolongs the mixed heat exchange process of steam and condensate, strengthens the mixed heat exchange effect, shortens the equipment length, saves space, and reduces equipment consumables.

Description

Technical Field

[0001] The present invention relates to the field of power plants, in particular to an ejection heater for a heat recovery system in a power plant. Background Art

[0002] The power industry is a foundational sector of my country's national economy and holds the lifeblood of the national economy. Thermal power generation accounts for approximately 70% of my country's total power generation. Improving the efficiency of thermal power generation systems and reducing coal consumption are key energy conservation indicators for thermal power plants. The heat recovery system heats feedwater by extracting steam from the steam turbine, effectively improving the overall efficiency of a thermal power plant. The heat transfer efficiency of the heat exchanger in the heat recovery system is key to the performance of the entire system and directly affects the coal consumption of the power plant.

[0003] In the heat recovery system, an ejector heater is installed as a converging heater as needed. This heater raises the feedwater pressure, injects high-temperature steam through an ejector, and mixes the high-temperature steam with the feedwater within the ejector to achieve the desired temperature increase. Ejector heaters offer a simple structure, stable operation, low cost, and easy maintenance, making them highly efficient steam recovery devices. However, traditional ejector heaters are large, and the direct mixing of high-pressure, high-temperature steam with the feedwater results in significant energy losses and poor thermal performance. Therefore, an ejector heater for power plant heat recovery systems has become a pressing need in the field. Summary of the Invention

[0004] The main technical problem solved by the present invention is to provide an ejection heater for a power plant heat recovery system, which can enhance the heat exchange effect of a traditional ejection heater and increase the efficiency of the power plant heat recovery system.

[0005] In order to solve the above technical problems, a technical solution adopted by the present invention is:

[0006] A power plant heat recovery system ejection heater comprises a circular shell 1, a tapered structure 2, a gradually expanding structure 3, an outer spiral baffle 4, an inner spiral baffle 5 and an ejection hole 6; the circular shell 1 is provided with a circular interface a11; the tapered structure 2 is provided with a circular interface b21, an annular boss 22 and a tapered section 23; the gradually expanding structure 3 is provided with an expanding section 31 and a circular interface c32; the outer spiral baffle 4 is provided with a long spiral baffle 41, a short spiral baffle 42 and a baffle 43; the ejection hole 6 is provided at the connection between the tapered structure 2 and the gradually expanding structure 3.

[0007] The circular shell 1 is a cylindrical hollow shell with an inner diameter of 400 mm, a thickness of 10 mm and a length of 2000 mm; the circular interface a11 on the circular shell 1 has an inner diameter of 160 mm and an outer diameter of 180 mm. The central axis of the circular interface a11 is 150 mm away from the right end plane of the circular shell 1, and the upper port plane of the circular interface a11 is 300 mm away from the central axis of the circular shell 1.

[0008] The circular interface b21 on the tapered structure 2 is a hollow cylindrical shell with an inner diameter of 240 mm, a thickness of 10 mm, and a length of 150 mm; the tapered section 23 is a conical shell with a shell thickness of 10 mm, an inner diameter tapering from 240 mm to 80 mm, and a length of 980 mm; the annular boss 22 is a hollow cylinder with an outer diameter of 400 mm, an inner diameter of 240 mm, and a length of 20 mm, and is arranged between the circular interface b21 and the tapered section 23; the axes of the circular interface b21, the annular boss 22, and the tapered section 23 are in the same straight line.

[0009] The gradually expanding section 31 on the gradually expanding structure 3 is a conical shell with a thickness of 10 mm, an inner diameter gradually expanding from 80 mm to 380 mm, and a length of 1000 mm; the circular interface c32 on the gradually expanding structure 3 is a cylindrical shell with a thickness of 10 mm, an inner diameter of 380 mm, and a length of 150 mm.

[0010] The outer spiral baffle 4 is composed of three parts: a long spiral baffle 41, a short spiral baffle 42 and a baffle 43; the long spiral baffle 41 is a hollow spiral baffle, the cross-section of the baffle perpendicular to the spiral direction is rectangular, the thickness is 15mm, the pitch is 360mm, the spiral is clockwise, the outer diameter of the long spiral baffle 41 is 400mm, and the interior is a hollow structure composed of two cones: gradually shrinking from 234.3mm to 100mm, the length is 820mm, and then gradually expanding from 100mm to 400mm, the length is 1000mm, and the overall length of the long spiral baffle 41 is 1820mm; the short spiral baffle 42 is a hollow spiral baffle, the cross-section perpendicular to the spiral direction is rectangular, the thickness is 15mm, the pitch is 360mm, the spiral is In the clockwise direction, the outer diameter of the short spiral baffle 42 is 400mm, and the interior is a hollow structure composed of two cones: it gradually shrinks from 260mm to 100mm, with a length of 980mm, and then gradually expands from 100mm to 154mm, with a length of 180mm, and the overall length is 1160mm; the baffle 43 is a trapezoidal plate with a thickness of 20mm, a trapezoidal height of 160mm, an upper bottom length of 144mm, and a lower bottom length of 112mm; the long spiral baffle 41 and the short spiral baffle 42 are coaxial, and the left end of the short spiral baffle 42 is 160mm away from the left end of the long spiral baffle 41. The baffle 43 is fixed by welding with the long spiral baffle 41 and the short spiral baffle 42 to the relative position between the short spiral baffle 42 and the long spiral baffle 41.

[0011] The inner spiral baffle 5 is a conical spiral structure, the cross section of the baffle perpendicular to the spiral direction is rectangular, the thickness is 15mm, the pitch is 280mm, the spiral is clockwise, the outer diameter of the inner spiral baffle 5 gradually expands from 134mm to 380mm, and the length is 820mm.

[0012] The left end of the inner spiral baffle 5 is inserted from the right side of the gradually expanding structure 3 until the outer wall of the inner spiral baffle 5 fits with the inner wall of the gradually expanding structure 3; the right end of the gradually contracting structure 2 is inserted from the left end of the long spiral baffle 41 until the left end of the short spiral baffle 42 on the outer spiral baffle 4 contacts the annular boss 22 on the gradually contracting structure 2; the left end of the gradually expanding structure 3 with the inner spiral baffle 5 is inserted from the right end of the long spiral baffle 41 until the left end of the gradually expanding structure 3 contacts the right end of the gradually contracting structure 2. The converging structure 2 is coaxial with the gradually expanding structure 3, that is, the hollow structure of the long spiral baffle 41 fits with the outer walls of the converging structure 2 and the gradually expanding structure 3, and the hollow structure of the short spiral baffle 42 fits with the outer walls of the converging structure 2 and the gradually expanding structure 3; the ejection hole 6 is a circular hole with a diameter of 40 mm, and the center of the ejection hole 6 is located at the connection between the converging structure 2 and the gradually expanding structure 3; the inner wall of the circular shell 1 fits with the outside of the outer spiral baffle 4, and the left end of the circular shell 1 is aligned with the left end of the annular boss 22.

[0013] The circular shell 1 is connected to the external steam side through the circular interface a11, so that the steam enters the enclosed space formed between the circular shell 1 and the tapered structure 2 and the gradually expanding structure 3. After entering the enclosed space, the steam will flow to the left end of the circular shell 1 under the guidance of the outer spiral baffle 4. When the steam flows to the baffle 43, the flow cross-section becomes smaller due to the obstruction of the short spiral baffle 42 and the baffle 43. After bypassing the baffle 43, the steam continues to flow to the left end of the circular shell 1 in the space on one side formed by the long spiral baffle 41 and the short spiral baffle 42. After reaching the left end of the circular shell 1, the steam will flow to the right end of the circular shell 1 in the space on the other side formed by the long spiral baffle 41 and the short spiral baffle 42 until the steam flows into the ejection hole 6; the condensate passes The condensate enters the heater through the circular interface b21 on the tapered structure 2. When the condensate flows through the tapered section 23 of the tapered structure 2, the condensate flow rate increases and the pressure decreases due to the reduction in the flow cross-section. When the condensate flows to the ejection hole 6, the condensate pressure drops to the lowest. At this time, the ejected steam enters the interior of the heater through the ejection hole 6. The steam and condensate are mixed in the gradually expanding section 31, and the mixed fluid flows in a spiral manner under the guidance of the inner spiral deflector 5 set in the gradually expanding section 31. Finally, the mixed and heat-exchanged fluid flows out of the equipment from the circular interface c32. During the entire heat exchange process, the steam and condensate are subjected to inter-wall heat exchange through the shells of the tapered section 23 and the gradually expanding section 31, and the steam enters the gradually expanding section 31 through the ejection hole 6 to perform mixed heat exchange with the condensate.

[0014] The beneficial effects of the present invention are:

[0015] The present invention provides an ejector heater for a power plant heat recovery system. Compared with a conventional mixed heater for a heat recovery system, a spiral baffle is added to the outside of the ejector heater, so that the steam and condensate entering the ejector undergo a wall-to-wall heat exchange, thereby increasing the condensate temperature before the steam and condensate are mixed, and reducing the irreversible loss of the mixed heat exchange; at the same time, by arranging a spiral baffle in the gradually expanding section of the ejector heater, the mixing process of the steam and condensate can be effectively prolonged, the mixed heat exchange effect can be improved, the equipment length can be shortened, space can be saved, and equipment consumables can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a three-dimensional view of the appearance of an ejector heater for a power plant regenerative system according to the present invention;

[0017] Figure 2 This is a three-dimensional view of the circular shell of an ejector heater of a power plant regenerative system according to the present invention;

[0018] Figure 3 A three-dimensional view of the tapered structure of an ejector heater for a power plant heat recovery system according to the present invention;

[0019] Figure 4 This is a three-dimensional view of the gradually expanding structure of an ejector heater of a power plant heat recovery system according to the present invention;

[0020] Figure 5 A three-dimensional view of the coordination of the tapered structure and the gradually diverging structure of an ejector heater of a power plant regenerative system according to the present invention;

[0021] Figure 6 This is a three-dimensional view of the outer spiral baffle of an ejector heater of a power plant regenerative system according to the present invention;

[0022] Figure 7 This is a three-dimensional view of the inner spiral baffle of an ejector heater of a power plant regenerative system according to the present invention;

[0023] Figure 8 A three-dimensional view of the assembly of the gradually expanding structure and the inner spiral baffle of an ejector heater of a power plant regenerative system according to the present invention;

[0024] Figure 9 A three-dimensional view of the tapered structure and outer spiral baffle assembly of an ejector heater of a power plant regenerative system according to the present invention;

[0025] Figure 10 This is a three-dimensional view of the assembly of the tapered structure, the gradually diverging structure and the outer spiral baffle of an ejector heater of a power plant regenerative system according to the present invention;

[0026] Figure 11 This is a top view of the assembly of the tapered structure, the gradually diverging structure and the outer spiral baffle of an ejector heater of a power plant regenerative system according to the present invention;

[0027] Figure 12 This is a perspective three-dimensional view of an ejector heater for a power plant heat recovery system according to the present invention. DETAILED DESCRIPTION

[0028] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more precise definition of the protection scope of the present invention.

[0029] A power plant heat recovery system ejection heater comprises a circular shell 1, a tapered structure 2, a gradually expanding structure 3, an outer spiral baffle 4, an inner spiral baffle 5 and an ejection hole 6; the circular shell 1 is provided with a circular interface a11; the tapered structure 2 is provided with a circular interface b21, an annular boss 22 and a tapered section 23; the gradually expanding structure 3 is provided with a gradually expanding section 31 and a circular interface c32; the outer spiral baffle 4 is provided with a long spiral baffle 41, a short spiral baffle 42 and a baffle 43; the ejection hole 6 is provided at the connection between the tapered structure 2 and the gradually expanding structure 3; the overall appearance structure is as follows Figure 1 shown.

[0030] As a preferred embodiment of the present invention, Figure 2 As shown, the circular shell 1 is a cylindrical hollow shell with an inner diameter of 400 mm, a thickness of 10 mm and a length of 2000 mm; the circular interface a11 on the circular shell 1 has an inner diameter of 160 mm and an outer diameter of 180 mm, the central axis of the circular interface a11 is 150 mm away from the right end plane of the circular shell 1, and the upper port plane of the circular interface a11 is 300 mm away from the central axis of the circular shell 1.

[0031] like Figure 3 As shown, the circular interface b21 on the tapered structure 2 is a hollow cylindrical shell with an inner diameter of 240 mm, a thickness of 10 mm, and a length of 150 mm; the tapered section 23 is a conical shell with a shell thickness of 10 mm, an inner diameter tapering from 240 mm to 80 mm, and a length of 980 mm; the annular boss 22 is a hollow cylinder with an outer diameter of 400 mm, an inner diameter of 240 mm, and a length of 20 mm, and is arranged between the circular interface b21 and the tapered section 23; the axes of the circular interface b21, the annular boss 22, and the tapered section 23 are in the same straight line.

[0032] like Figure 4 As shown, the gradually expanding section 31 on the gradually expanding structure 3 is a conical shell with a thickness of 10mm, an inner diameter gradually expanding from 80mm to 380mm, and a length of 1000mm; the circular interface c32 on the gradually expanding structure 3 is a cylindrical shell with a thickness of 10mm, an inner diameter of 380mm, and a length of 150mm; the connection form of the gradually contracting structure 2 and the gradually expanding structure 3 is as shown Figure 5shown.

[0033] like Figure 6 As shown, the outer spiral baffle 4 is composed of three parts: a long spiral baffle 41, a short spiral baffle 42 and a baffle 43; the long spiral baffle 41 is a hollow spiral baffle, the cross-section of the baffle perpendicular to the spiral direction is rectangular, the thickness is 15mm, the pitch is 360mm, the spiral is clockwise, the outer diameter of the long spiral baffle 41 is 400mm, and the interior is a hollow structure composed of two cones: gradually shrinking from 234.3mm to 100mm, the length is 820mm, and then gradually expanding from 100mm to 400mm, the length is 1000mm, and the overall length of the long spiral baffle 41 is 1820mm; the short spiral baffle 42 is a hollow spiral baffle, the cross-section perpendicular to the spiral direction is rectangular, the thickness is 15mm, the pitch is 360mm, the spiral is In the clockwise direction, the outer diameter of the short spiral baffle 42 is 400mm, and the interior is a hollow structure composed of two cones: it gradually shrinks from 260mm to 100mm, with a length of 980mm, and then gradually expands from 100mm to 154mm, with a length of 180mm, and the overall length is 1160mm; the baffle 43 is a trapezoidal plate with a thickness of 20mm, a trapezoidal height of 160mm, an upper bottom length of 144mm, and a lower bottom length of 112mm; the long spiral baffle 41 and the short spiral baffle 42 are coaxial, and the left end of the short spiral baffle 42 is 160mm away from the left end of the long spiral baffle 41. The baffle 43 is fixed by welding with the long spiral baffle 41 and the short spiral baffle 42 to the relative position between the short spiral baffle 42 and the long spiral baffle 41.

[0034] like Figure 7 As shown, the inner spiral baffle 5 is a conical spiral structure, the cross-section of the baffle perpendicular to the spiral direction is rectangular, the thickness is 15mm, the pitch is 280mm, the spiral is clockwise, the outer diameter of the inner spiral baffle 5 gradually expands from 134mm to 380mm, and the length is 820mm.

[0035] like Figure 8 As shown, the left end of the inner spiral baffle 5 is inserted from the right side of the gradually expanding structure 3 until the outer wall of the inner spiral baffle 5 fits with the inner wall of the gradually expanding structure 3; Figure 9 As shown, the right end of the tapered structure 2 penetrates from the left end of the long spiral baffle 41 until the left end of the short spiral baffle 42 on the outer spiral baffle 4 contacts the annular boss 22 on the tapered structure 2; Figure 10As shown, the left end of the gradually expanding structure 3 with the inner spiral baffle 5 is passed through the right end of the long spiral baffle 41 until the left end of the gradually expanding structure 3 contacts the right end of the gradually contracting structure 2, and the gradually contracting structure 2 and the gradually expanding structure 3 are coaxial, that is, the hollow structure of the long spiral baffle 41 fits with the outer walls of the gradually contracting structure 2 and the gradually expanding structure 3, and the hollow structure of the short spiral baffle 42 fits with the outer walls of the gradually contracting structure 2 and the gradually expanding structure 3; Figure 11 As shown, the ejection hole 6 is a circular hole with a diameter of 40 mm. The center of the ejection hole 6 is located at the connection between the gradually converging structure 2 and the gradually expanding structure 3. The inner wall of the circular shell 1 is fitted with the outer side of the outer spiral baffle 4. The left end of the circular shell 1 is aligned with the left end of the annular boss 22. After completing all the above assemblies, the heater is as shown in FIG. Figure 12 shown.

[0036] The circular shell 1 is connected to the external steam side through the circular interface a11, so that the steam enters the enclosed space formed between the circular shell 1 and the tapered structure 2 and the gradually expanding structure 3. After entering the enclosed space, the steam will flow to the left end of the circular shell 1 under the guidance of the outer spiral baffle 4. When the steam flows to the baffle 43, the flow cross-section becomes smaller due to the obstruction of the short spiral baffle 42 and the baffle 43. After bypassing the baffle 43, the steam continues to flow to the left end of the circular shell 1 in the space on one side formed by the long spiral baffle 41 and the short spiral baffle 42. After reaching the left end of the circular shell 1, the steam will flow to the right end of the circular shell 1 in the space on the other side formed by the long spiral baffle 41 and the short spiral baffle 42 until the steam flows into the ejection hole 6; the condensed water passes through The circular interface b21 on the tapered structure 2 enters the heater. When the condensate flows through the tapered section 23 of the tapered structure 2, the condensate flow rate increases and the pressure decreases due to the reduction in the flow cross-section. When the condensate flows to the ejection hole 6, the condensate pressure drops to the lowest. At this time, the ejected steam enters the interior of the heater through the ejection hole 6. The steam and condensate are mixed in the expanding section 31, and the mixed fluid flows in a spiral manner under the guidance of the inner spiral deflector 5 set in the expanding section 31. Finally, the mixed and heat-exchanged fluid flows out of the equipment from the circular interface c32. During the entire heat exchange process, the steam and condensate are subjected to inter-wall heat exchange through the shells of the tapered section 23 and the expanding section 31, and the steam enters the expanding section 31 through the ejection hole 6 to perform mixed heat exchange with the condensate.

[0037] In summary, the present invention provides an ejector heater for a heat recovery system of a power plant. By adding a spiral baffle on the outside of the ejector heater, the steam entering the ejector and the condensate are subjected to a wall-to-wall heat exchange, thereby increasing the temperature of the condensate before the steam and condensate are mixed, and reducing the irreversible loss of the mixed heat exchange. At the same time, by arranging a spiral baffle in the gradually expanding section of the ejector heater, the mixing process of the steam and condensate can be effectively prolonged, the mixed heat exchange effect can be improved, the length of the equipment can be shortened, space can be saved, and equipment consumables can be reduced.

Claims

1. An ejector heater for a heat recovery system in a power plant, characterized by: The invention comprises a circular shell (1), a gradually contracting structure (2), a gradually expanding structure (3), an outer spiral baffle (4), an inner spiral baffle (5) and an ejection hole (6); the circular shell (1) is provided with a circular interface a (11); the gradually contracting structure (2) is provided with a circular interface b (21), an annular boss (22) and a gradually contracting section (23); the gradually expanding structure (3) is provided with a gradually expanding section (31) and a circular interface c (32); the outer spiral baffle (4) is provided with a long spiral baffle (41), a short spiral baffle (42) and a baffle ( 43); the ejection hole (6) is provided at the connection between the gradually contracting structure (2) and the gradually expanding structure (3); the outer spiral baffle (4) is composed of three parts: a long spiral baffle (41), a short spiral baffle (42) and a baffle (43); the long spiral baffle (41) is a hollow spiral baffle, the cross section of the baffle perpendicular to the spiral direction is rectangular, the thickness is 15mm, the pitch is 360mm, the spiral is in a clockwise direction, the outer diameter of the long spiral baffle (41) is 400mm, and the interior is a hollow structure composed of two cones: 234.The short spiral baffle (42) is a hollow spiral baffle with a rectangular cross section perpendicular to the spiral direction, a thickness of 15 mm, a pitch of 360 mm, and a spiral in a clockwise direction. The outer diameter of the short spiral baffle (42) is 400 mm, and the interior is a hollow structure composed of two cones: the short spiral baffle (42) is gradually narrowed from 260 mm to 100 mm, and the length is 1000 mm. The baffle (43) is a trapezoidal plate with a thickness of 20 mm, a trapezoidal height of 160 mm, an upper bottom length of 144 mm, and a lower bottom length of 112 mm. The long spiral baffle (41) and the short spiral baffle (42) are coaxial, and the left end of the short spiral baffle (42) is 160 mm away from the left end of the long spiral baffle (41). The baffle (43) is connected to the long spiral baffle (41) and the short spiral baffle (42) by connecting the baffle (43) with the long spiral baffle (41) and the short spiral baffle (42). 42) are welded to fix the relative position between the short spiral baffle (42) and the long spiral baffle (41); the converging structure (2) and the expanding structure (3) are coaxial, and the right end of the converging structure (2) is matched with the left end of the expanding structure (3); the ejection hole (6) is a circular hole with a diameter of 40 mm, and the center of the ejection hole (6) is located at the connection between the converging structure (2) and the expanding structure (3); the left end of the short spiral baffle (42) on the outer spiral baffle (4) contacts the annular boss (22) on the converging structure (2), that is, the long spiral baffle The hollow structure of (41) fits with the outer walls of the gradually converging structure (2) and the gradually expanding structure (3), and the hollow structure of the short spiral baffle (42) fits with the outer walls of the gradually converging structure (2) and the gradually expanding structure (3); the inner wall of the circular shell (1) fits with the outer sides of the inner spiral baffle (5) and the outer sides of the outer spiral baffle (4), and the left end of the circular shell (1) is aligned with the left end of the annular boss (22); the inner spiral baffle (5) is arranged inside the gradually expanding structure (3), and the outer wall of the inner spiral baffle (5) fits with the inner wall of the gradually expanding structure (3).

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