Flue gas heat exchanger

Abstract

The present invention discloses a flue gas heat exchanger, comprising a heat exchange module, wherein the heat exchange module comprises a plurality of rows of heat exchange tube assemblies, wherein one row of the heat exchange tube assemblies comprises a plurality of heat exchange tube assemblies arranged in sequence along a first direction; one of the heat exchange tube assemblies comprises a heat pipe and an outer sleeve, wherein a portion of each heat pipe is inserted into the corresponding outer sleeve, and both ends of the outer sleeve are sealed and connected to the heat pipe, and cooling water can flow between the inner wall of the outer sleeve and the outer wall of the corresponding heat pipe; in each row of the heat exchange tube assemblies, a plurality of the outer sleeves are connected alternately up and down in sequence along the first direction. The heat exchange module in the flue gas heat exchanger of the present invention comprises a plurality of rows of heat exchange tube assemblies, wherein the outer sleeves of each row of the heat exchange tube assemblies are connected alternately up and down in sequence, so that each row of the heat exchange tube assemblies can form a serpentine labyrinth flow channel, and the cooling water flows in opposite directions in the outer sleeves of adjacent heat exchange tube assemblies, thereby effectively improving the heat exchange capacity.

Description

Technical Field

[0001] The invention relates to the technical field of heat exchange, and in particular to a flue gas heat collector. Background Art

[0002] Low-temperature electrostatic precipitator technology has been widely promoted and applied in the ultra-low emission transformation of coal-fired units and new units in my country in recent years. As a specific flue gas heat exchanger, the low-temperature economizer can not only realize the effective recovery and utilization of flue gas waste heat, but also effectively improve the dust removal efficiency and achieve the synergistic capture of sulfur trioxide in the flue gas when arranged in front of the electrostatic precipitator. It is a flue gas heating and energy-saving and environmental protection technology that is very consistent with national policies.

[0003] At present, there is a heat pipe flue gas cooler, which includes a shell, and a plurality of vacuum heat pipes with working fluids are arranged inside the shell. The upper part of each heat pipe is covered with a sleeve, and the upper ends of all the sleeves are connected to the upper header, and the lower ends are connected to the lower header. Cooling water flows into the upper header and flows to each sleeve, and then is between the inner wall of the sleeve and the outer wall of the corresponding heat pipe, absorbing the heat of the working fluid at the top of the heat pipe. After the working fluid releases heat, it condenses and flows to the evaporation section at the bottom of the heat pipe, continuing to absorb the heat of the flue gas. The cooling water after absorbing heat flows out from the lower header. However, the heat exchange efficiency of this solution is difficult to further improve. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a flue gas heat collector, including a heat exchange module, the heat exchange module including multiple rows of heat exchange tube assemblies, one row of the heat exchange tube assemblies including multiple heat exchange tube assemblies arranged in sequence along a first direction; one of the heat exchange tube assemblies includes a heat pipe and an outer sleeve, a portion of each of the heat pipes is inserted into the corresponding outer sleeve, both ends of the outer sleeve are sealed and connected to the heat pipe, and cooling water can flow between the inner wall of the outer sleeve and the corresponding outer wall of the heat pipe; in each row of the heat exchange tube assemblies, multiple outer sleeves are connected alternately up and down in sequence in the first direction.

[0005] Optionally, both ends of the heat pipe and the outer sleeve are airtightly welded.

[0006] Optionally, both ends of the outer sleeve are extruded conical closing structures, and the inner diameter of the conical closing structure is equal to or slightly larger than the outer diameter of the heat pipe.

[0007] Optionally, the heat exchange module also includes an inlet pipe and an outlet pipe, and each row of the heat exchange tube assemblies includes end heat exchange tube assemblies respectively located at both ends of the first direction, and the outer sleeves of all the end heat exchange tube assemblies located at one end of the multiple rows of heat exchange tube assemblies are connected to the inlet pipe, and the outer sleeves of all the end heat exchange tube assemblies located at the other end are connected to the outlet pipe.

[0008] Optionally, the flue gas heat collector includes a heat exchange part, which includes at least one row of the heat exchange modules, and each row of the heat exchange modules includes at least one heat exchange module; the heat exchange modules in each row of the heat exchange modules are arranged along a second direction perpendicular to the first direction, and multiple rows of heat exchange modules are arranged along the first direction.

[0009] Optionally, the flue gas flows along the first direction, and the flow direction is opposite to the overall flow direction of the cooling water in a row of the heat exchange tube assemblies.

[0010] Optionally, the flue gas heat exchanger also includes an inlet main pipe and an outlet main pipe; the heat exchange part includes multiple rows of heat exchange modules, the inlet pipes of all the heat exchange modules in the front row are connected to the inlet main pipe, the outlet pipes of all the heat exchange modules in the back row are connected to the outlet main pipe, and in adjacent rows of heat exchange modules, the inlet pipe of one and the outlet pipe of the other are connected one-to-one; or, the heat exchange part includes a row of heat exchange modules, the inlet pipes of all the heat exchange modules are connected to the inlet main pipe, and the outlet pipes of all the heat exchange modules are connected to the outlet main pipe.

[0011] Optionally, the heat pipe and the outer sleeve are arranged at an angle.

[0012] Optionally, the tilt angle is 0-15 degrees.

[0013] Optionally, the heat exchange module further includes a plurality of grooved partitions, each of which extends along a first direction; a plurality of heat pipes in a row of the heat exchange tube assemblies penetrate a corresponding grooved partition, and the portion of the heat pipe below the grooved partition is its evaporation section.

[0014] Optionally, the flue gas heat exchanger further comprises an intelligent control unit, which collects the operating data of the flue gas heat exchanger in real time and compares and analyzes the data with the set benchmark data. When it is determined through intelligent calculation that the current operating data deviates significantly from the preset benchmark data, an equipment failure warning is issued.

[0015] Optionally, the flue gas heat collector further comprises an online temperature measuring unit for detecting the temperature of the condensation section of the heat pipe.

[0016] The heat exchange module in the flue gas heat exchanger of the present invention includes multiple rows of heat exchange tube assemblies, and the outer sleeves of each row of heat exchange tube assemblies are alternately connected up and down in sequence, so that each row of heat exchange tube assemblies can form a serpentine maze flow channel, and the cooling water in the outer sleeves of adjacent heat exchange tube assemblies flows in opposite directions, thereby effectively improving the heat exchange capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1A schematic structural diagram of a specific embodiment of the flue gas heat exchanger provided by the present invention;

[0018] Figure 2 for Figure 1 A top view of

[0019] Figure 3 for Figure 1 Magnified view of area A.

[0020] Figure 4 for Figure 1 A schematic diagram of a heat exchange tube assembly;

[0021] Figure 5 for Figure 1 Schematic diagram of the heat exchange part in the upper part of the middle shell;

[0022] Figure 6 for Figure 5 A schematic diagram of the upper part of a heat exchange module;

[0023] Figure 7 for Figure 5 Magnified view of area B.

[0024] Figure 8 is a schematic diagram of the flow of working fluid in a vertically arranged heat pipe;

[0025] Fig. 9 Schematic diagram of the flow of working fluid in an inclined heat pipe.

[0026] Figure 1-9 The reference numerals in the figures are described as follows:

[0027] 101-inlet smoke box; 102-housing; 103-exit smoke box;

[0028] 20-cleaning unit;

[0029] 30-heat exchange module; 301-inlet pipe; 302-outlet pipe; 303-heat exchange tube assembly; 303a-outer casing; 303ba-liquid film; 303b-heat pipe; 303b1-condensation section; 303b2-evaporation section; 303b3-fin; 304-groove partition; 305-connecting pipe; 306-drain pipe; 307-drain pipe;

[0030] 40-online temperature measurement unit;

[0031] 50-Intelligent control unit;

[0032] 601-import main pipe; 602-export main pipe;

[0033] 70-connecting pipe;

[0034] 80-Dust flow distribution unit. DETAILED DESCRIPTION

[0035] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0036] Please refer to Figure 1-2 , Figure 1 A schematic structural diagram of a specific embodiment of the flue gas heat exchanger provided by the present invention; Figure 2 for Figure 1 A top view of Figure 3 for Figure 1 A magnified view of the middle A area; Figure 4 for Figure 1 Schematic diagram of a heat exchange tube assembly 303.

[0037] like Figure 1 The flue gas heat exchanger comprises a housing 102 and an inlet smoke box 101 and an outlet smoke box 103 located at both ends of the housing 102. The smoke enters the housing 102 through the inlet smoke box 101 and flows out from the outlet smoke box 103. At least one of the inlet smoke box 101, the housing 102, and the outlet smoke box 103 may be provided with a dust removal unit 20 to clean the deposition of particulate matter in the smoke.

[0038] The flue gas heat collector can be arranged on the flue gas channel of the flue gas waste heat to recover the flue gas waste heat. To this end, the flue gas heat collector includes a heat exchange part, and the heat exchange part includes at least one heat exchange module 30, such as Figure 2 The heat exchange unit shown includes ten heat exchange modules 30. The heat exchange modules 30 include multiple rows of heat exchange tube assemblies 303. A row of heat exchange tube assemblies 303 includes multiple heat exchange tube assemblies 303 arranged in sequence. The arrangement direction of a row of heat exchange tube assemblies 303 is defined as a first direction in this article. The direction can be as follows: Figure 2 The direction of the straight line shown in may not be a straight line. Figure 4 As shown, a heat exchange tube assembly 303 includes a heat pipe 303b and an outer sleeve 303a, a portion of each heat pipe 303b is inserted into the corresponding outer sleeve 303a, and both ends of the outer sleeve 303a are sealed and connected to the heat pipe 303b, as shown in FIG. Figure 3 As shown, a cooling cavity is formed between the inner wall of the outer sleeve 303a and the outer wall of the corresponding heat pipe 303b, and cooling water can flow through the cooling cavity. Figure 4 As shown, the length of the heat pipe 303b is greater than that of the outer sleeve 303a, the lower part of the heat pipe 303b is located in the shell 102 of the flue gas heat exchanger, and the upper part of the heat pipe 303b is located above the shell 102. When the dust cleaning unit 20 is arranged on the shell 102, not only the dust accumulated on the shell 20 can be cleaned, but also the dust accumulated on the heat pipe 303b can be cleaned.

[0039] Look again Figure 3The upper part of the heat pipe 303b is almost inserted into the outer sleeve 303a. The part of the heat pipe 303b inserted into the outer sleeve 303a can be defined as the condensation section 303b1, and the part located in the shell 102 for heat exchange with the high-temperature flue gas can be defined as the evaporation section 303b2. In order to improve the heat exchange efficiency of the evaporation section 303b2, a plurality of fins 303b3 are also arranged on the outer wall of the evaporation section 303b2.

[0040] For further reference Figure 5 , 6 understand, Figure 5 for Figure 1 A schematic diagram of the heat exchange portion at the upper portion of the middle shell 102; Figure 6 for Figure 5 Schematic diagram of the upper part of a heat exchange module 30.

[0041] Figure 6 From the perspective of the heat exchange module 30, only the upper part of a row of heat exchange tube assemblies 303 is shown, and the lower part of the heat pipe 303b is not shown. In this embodiment, in each row of heat exchange tube assemblies 303, multiple outer sleeves 303a are connected alternately up and down in sequence along the arrangement direction of the heat exchange tube assemblies 303. That is, in each row of heat exchange tube assemblies 303, the upper end of an outer sleeve 303a is connected to the upper end of an adjacent outer sleeve 303a, and the lower end is connected to the lower end of another adjacent outer sleeve 303a. For the outer sleeves 303a located at both ends, the upper and lower ends are connected in such a way that one end is connected to the corresponding end of the adjacent outer sleeve 303a, and the other end serves as the inlet or outlet of the cooling water. In this way, multiple outer sleeves 303a in a row of heat exchange tube assemblies 303 are arranged side by side, and at the same time, they are connected in series by alternating up and down. Figure 6 The figure shows a row of heat exchange components forming a serpentine flow channel, and the cooling water in adjacent outer sleeves 303a flows in opposite directions, and the arrows in the outer sleeves 303a indicate the flow direction of the cooling water. The upper ends or lower ends of adjacent outer sleeves 303a can be connected through a connecting pipe 305.

[0042] With such arrangement, the heat exchange module 30 includes multiple rows of heat exchange tube assemblies 303, each row of heat exchange tube assemblies 303 forms a serpentine labyrinth flow channel, and the cooling water flows in the outer sleeves 303a of adjacent heat exchange tube assemblies 303 in opposite directions, thereby increasing the relative temperature difference and effectively improving the heat exchange capacity.

[0043] In addition, if Figure 1 As shown, the flue gas enters and leaves the flue gas heat exchanger from left to right, and the cooling water can flow into and out of the heat exchange part from right to left, that is, the flow direction of the flue gas and the overall flow direction of the cooling water are completely opposite, and the cooling water is in a countercurrent state relative to the flue gas, thereby further improving the comprehensive heat exchange capacity.

[0044] like Figure 2As shown, the heat exchange module 30 also includes an inlet pipe 301 and an outlet pipe 302. Each row of heat exchange tube assemblies 303 includes end heat exchange tube assemblies 303 located at both ends respectively. The outer sleeves 303a of all the end heat exchange tube assemblies 303 located at one end of the multiple rows of heat exchange tube assemblies 303 are connected to the inlet pipe 301, and the outer sleeves 303a of all the end heat exchange tube assemblies 303 located at the other end are connected to the outlet pipe 302. In this way, one inlet pipe 301 can provide cooling water to all rows of heat exchange tube assemblies 303 of a heat exchange module 30, and the cooling water in the outer sleeves 303a of all rows of heat exchange tube assemblies 303 flows out through one outlet pipe 302. Such a heat exchange module 30 only needs to be provided with one inlet pipe 301 and one outlet pipe 302, which is convenient for controlling the inlet and outlet of cooling water, and can also greatly save materials. Of course, each row can also be controlled by a separate inlet and outlet pipe.

[0045] Please continue to refer to Figure 3 The heat pipe 303b and the outer sleeve 303a are preferably sealed and connected by airtight welding. This sealing connection method is reliable and easy to implement. Of course, other methods can also be used to achieve the sealing connection, such as setting a sealing member. Figure 3 As shown, specifically, both ends of the outer sleeve 303a can be extruded conical closing structures, and the inner diameter of the conical closing structure is equal to or slightly larger than the outer diameter of the heat pipe 303b, so that the outer sleeve 303a and the heat pipe 303b are easy to pre-position after initial sleeve connection, and because the conical closing structure fits tightly with the outer wall of the heat pipe 303b or there is a small gap after the sleeve connection, it is easy to perform welding operations on the connection position.

[0046] Also, please refer to Figure 7 , Figure 7 for Figure 5 Magnified view of area B.

[0047] like Figure 6 As shown, since a row of heat exchange tube assemblies 303 are alternately connected from top to bottom, the lower ends of a row of heat exchange tube assemblies 303 are disconnected at intervals. At this time, a thin tube can be set as a drain pipe 306 to connect the two adjacent outer tubes 303a that are disconnected at the lower ends. Since the drain pipe 306 is thinner and its diameter is much smaller than the connecting pipe 305 at the lower end, it does not affect the serpentine flow direction of the cooling water during operation. However, when the equipment stops working and the water inside the heat pipe 303a needs to be drained, the lower ends of all the outer tubes 303a in a row form a waterway at the lower end through the drain pipe 306 and the connecting pipe 305, which is conducive to completely draining the water inside the outer tube 303a. Figure 7 A drain pipe 307 and a drain valve for controlling the opening and closing of the drain outlet of the drain pipe 307 are shown.

[0048] Please continue to refer to Figure 2The heat exchange part includes at least one row of heat exchange modules 30 , each row of heat exchange modules 30 includes at least one heat exchange module 30 , and one row of heat exchange modules 30 is distributed along the arrangement direction of multiple rows of heat exchange tube assemblies 303 in the heat exchange modules 30 . Figure 2 In the embodiment, the heat exchange part includes two rows of heat exchange modules 30 distributed left and right, one row includes five heat exchange modules 30 distributed up and down, and the multiple rows of heat exchange tube assemblies 303 in each heat exchange module 30 are also distributed up and down, and there are sixteen rows of heat exchange tube assemblies 303 distributed. Figure 6 In the figure, each row of heat exchange tube assemblies 303 includes fourteen heat exchange tube assemblies 303. Of course, these quantity settings are only specific examples, and the specific heat exchange component specifications can be determined according to specific heat exchange requirements, setting space and other factors. Figure 2 In the figure, the arrangement direction of multiple rows of heat exchange modules 30 is consistent with the direction of flue gas flow, and the two rows of heat exchange modules 30 are distributed left and right, and the flue gas and cooling water enter and exit in the left and right directions; the arrangement direction of the heat exchange modules 30 in each row of heat exchange modules 30 is perpendicular to the direction of flue gas flow, and the above arrangement directions are all located in the horizontal plane, and it can be seen that distribution along the vertical plane is also possible.

[0049] like Figure 2 As shown, the flue gas heat exchanger in this embodiment may also include an inlet manifold 601 and an outlet manifold 602. The inlet pipes 301 of the front row of heat exchange modules 30 are all connected to the inlet manifold 601, and the outlet pipes 302 of the rear row of heat exchange modules 30 are all connected to the outlet manifold 602. Here, the front and rear refer to the heat exchange module rows at both ends of the heat exchange part. In addition, in adjacent rows of heat exchange modules 30, the inlet pipe 301 of one and the outlet pipe 302 of the other are connected one by one, which can be specifically achieved by Figure 2 Of course, when there is only one row of heat exchange modules 30, all the inlet pipes 301 and outlet pipes 302 at both ends of the row of heat exchange modules 30 are connected to the inlet main pipe 601 and the outlet main pipe 602 respectively.

[0050] With such a configuration, the entire heat exchange unit can realize the inflow and outflow of cooling water through one inlet manifold 601 and one outlet manifold 602. Although the multiple outer casings 303a at the ends of a row of heat exchange modules 30 can be connected to the inlet manifold 601 and the outlet manifold 602 at the same time, the configuration of this embodiment is conducive to the increase and decrease, maintenance, and inflow and outflow control of cooling water of each heat exchange module 30. For example, when Figure 2 When any of the two series-connected heat exchange modules 30 in the middle and lower parts fails, the inlet main pipe 601, the outlet main pipe 602 and the passages of the two heat exchange modules 30 can be shut down, and the remaining heat exchange modules 30 can still work normally.

[0051] Please continue to refer to Figure 6 , and combined with Figure 8 , 9 , Figure 8 is a schematic diagram of the flow of working fluid in the vertically arranged heat pipe 303b; Fig. 9 It is a schematic diagram of the flow of working medium in the inclined heat pipe 303b.

[0052] The heat exchange tube assembly 303 is tilted, that is, the heat pipe 303b and the outer sleeve 303a are both tilted. As mentioned above, the heat pipe 303b of the heat exchange tube assembly 303 in this embodiment includes a condensation section 303b1 and an evaporation section 303b2. The condensation section 303b1 is located in the outer sleeve 303a, and the flue gas contacts the evaporation section 303b2 below. There is a working medium in the heat pipe 303b and the heat pipe 303b is kept in a vacuum. After the evaporation section 303b2 contacts the high-temperature flue gas, it transfers heat to the working medium, and the working medium absorbs heat and quickly evaporates and changes into steam in the vacuum atmosphere. Under the action of the upper and lower pressure differences, it automatically rises to the upper condensation section 303b1. After flowing to the upper condensation section 303b1, it continuously transfers heat to the cooling water through the tube wall to release heat. The working medium condenses into a liquid and then flows down to the evaporation section 303b2. Each heat pipe 303b is independently arranged, and its evaporation section 303b2 is in the flue gas, and there is a possibility of being worn by particles in the flue gas. When a certain evaporation section 303b2 is worn by flue gas particles, the working fluid inside the heat pipe 303b will leak into the flue gas, but because the cooling water is isolated on the outside of the pipe by the condensation section 303b1 above the flue gas, it will not cause the cooling water to leak into the flue gas continuously, which can reduce or even avoid the leakage of cooling water, and is conducive to achieving zero leakage. In addition, the above-mentioned cooling water after absorbing heat can be transported to the occasion where it is needed, so as to achieve the purpose of reducing the flue gas temperature and recovering the waste heat of the flue gas. The cooled flue gas will eventually flow out of the outlet smoke box 103 and flow to the downstream equipment.

[0053] like Figure 8 As shown, when the heat pipe 303b and the outer sleeve 303a are arranged vertically, when the working fluid in the heat pipe 303b flows back from the condensation section 303b1, the liquid film 303ba formed in the heat pipe 303b is relatively evenly distributed on the circumferential inner wall of the heat pipe 303b, which will cause a large thermal resistance. Fig. 9 As shown, in this embodiment, when the heat pipe 303b and the outer sleeve 303a are both inclined, the liquid film 303ba will be more concentrated on the inclined side due to gravity when the working fluid flows downward after condensation, that is, it will flow along the inner wall of the lower inclined side, such as Fig. 9 As shown, the liquid film 303ba will flow more concentratedly on the inner wall of the condensation section 303b1 close to the right side, occupying a smaller inner wall area, thereby reducing thermal resistance and achieving a better heat exchange effect.

[0054] Of course, the tilt angle does not have to be too large. As a preferred solution, the tilt angle can be 0-15 degrees, that is, greater than 0 degrees and less than or equal to 15 degrees. The tilt angle is the angle with the plumb plane. This can not only achieve the purpose of reducing thermal resistance, but also take into account the rising capacity of the steam formed after the working fluid evaporates. Of course, the tilt angle is not specifically limited here and can be flexibly adjusted according to the site conditions of the actual project. In addition, Figure 6 The heat exchange tube assembly 303 shown in the figure is tilted to the right. It can be seen that the heat exchange tube assembly 303 can be tilted in any direction, such as to the left, or tilted inward or outward perpendicular to the paper plane.

[0055] Please combine Figure 1 and Figure 3 It is understood that the heat exchange module 30 further includes a plurality of grooved baffles 304, the grooved baffles 304 extending along the first direction, the openings of the grooved baffles 304 facing upward, and the heat pipes 303b of the plurality of heat exchange tube assemblies 303 in each row of heat exchange tube assemblies 303 all pass through a grooved baffle 304, so as to Figure 2 As a viewing angle, the arrangement direction of the plurality of heat exchange tube assemblies 303 in a row of heat exchange tube assemblies 303 is defined as a first direction, that is, Figure 2 The arrangement direction of the multiple rows of heat exchange tube assemblies 303 is the second direction, that is, Figure 2 In the vertical direction, the extending direction of the grooved partition 304 is the same as the arrangement direction of a row of heat exchange tube assemblies 303, and the plurality of grooved partitions 304 are distributed along the second direction. It can be seen that a grooved partition 304 assembles a row of heat exchange tube assemblies 303 together, making the row of heat exchange tube assemblies 303 a whole. At the same time, adjacent grooved partitions 304 can be sealed and connected, such as being fixed by airtight welding, such as Figure 3 As shown, the side walls of adjacent grooved partitions 304 are welded and fixed together, so that all the grooved partitions 304 are connected as a whole, and the entire heat exchange module 30 can be divided into upper and lower parts, and the flue gas can flow under the grooved partitions 304, and all the outer sleeves 303a of the heat exchange module 30 are located above the grooved partitions 304, as shown in FIG. Figure 3 As shown, the portion of the heat pipe 303b located above the grooved partition 304 is basically the condensation section 303b1.

[0056] At this time, the flue gas can only pass under the grooved baffle 304, and cannot pass through the grooved baffle 304, and the cooling water located above it cannot pass through the grooved baffle 304, which is the flue gas side; in addition, the cooling water is sealed inside the outer sleeve 303a of the heat pipe 303b. In actual operation, the cooling water cannot pass through the outer sleeve 303a to reach the grooved baffle 304, nor can it enter the flue gas. Therefore, the gas-water separation of the heat exchange part of the flue gas heat exchanger in this embodiment is safer and has a double isolation function, which makes it easier to ensure that the cooling water will not leak into the flue gas during normal operation.

[0057] The above grooved partition 304 is a specific example. It can be understood that a layer of integral partition can be directly provided, or multiple heat pipes 303b can pass through the partition and be sealed and connected. However, it is obvious that the provision of multiple grooved partitions 304 can improve its structural strength on the one hand, and it is also easier to connect with the heat exchange tube assembly 303. First, a row of integral heat exchange tube assemblies 303 is formed, and then multiple rows of heat exchange tube assemblies 303 are fixed into a module, namely, the heat exchange module 30, by welding the grooved partitions 304.

[0058] like Figure 1 As shown, in this embodiment, the flue gas heat exchanger is also provided with an intelligent control unit 50, which can collect the operation data of the flue gas heat exchanger in real time, and compare and analyze it with the set benchmark data. When it is determined after intelligent calculation that the current operation data has a large deviation from the preset benchmark data, an equipment failure warning is issued, and the warning information can be pushed to the operation and maintenance personnel in a mobile way such as SMS or WeChat for timely processing. The above-mentioned operation data can specifically include boiler load, flue gas volume, soot blowing frequency of SCR / air preheater / flue gas heat exchanger, inlet and outlet flue gas temperature of flue gas heat exchanger, inlet and outlet water temperature of cooling water, inlet and outlet pressure difference and wall temperature of the end of condensing section 303b1 of heat pipe 303b. The intelligent control unit 50 can be connected with the whole plant monitoring and management system to realize the control of the whole life cycle management of the flue gas heat exchanger. It can be seen that the intelligent control unit 50 and the corresponding data monitoring unit realize the combination of big data, Internet+, Internet of Things and online monitoring and fault diagnosis technology to realize deep energy-saving operation and health management of equipment.

[0059] Please continue to refer to Figure 1 The flue gas heat collector is also provided with an online temperature measurement unit 40, which can perform online detection and data analysis on the operating temperature of the heat pipe 303b. Specifically, the temperature at the end of the condensing section 303b1 of the heat pipe 303b can be detected. Under a certain vacuum degree, the temperature change at the end of the heat pipe 303b is certain. When the temperature has a large change deviation, it indicates that the vacuum degree has changed, so that it can be monitored whether the heat pipe 303b has a fault. It can be seen that the online temperature measurement unit 40 can be set to grasp the working status of the heat pipe 303b at any time, timely guide the operation management and maintenance of the equipment, and ensure the normal use effect of the equipment.

[0060] like Figure 1 As shown, the flue gas heat collector in this embodiment can also be provided with a dust flow distribution unit 80, which is arranged in the inlet smoke box 101, which is conducive to achieving uniform flow of flue gas, so that it flows evenly to the lower part of the heat pipe 303b of the heat exchange part, thereby improving the heat exchange efficiency.

[0061] The dust flow distribution unit 90 can be composed of a multi-directional folding plate assembly and a composite design with a number of delta wings. Among them, the multi-directional folding plates are mainly welded into one body according to certain spacing and angles based on the results of computer numerical simulation, and the delta wings are welded obliquely on the folding plates near the flue gas outlet end. After the flue gas passes through the dust flow distribution unit 80, the multi-directional folding plates can realize the uniform distribution of the flue gas flow field in the entire flue cross section, which is beneficial to improve the heat exchange effect, and the delta wings can realize the uniform distribution of dust particle concentration in the inlet space of the flue gas heat exchanger, preventing the local excessive dust concentration from causing erosion and wear of the flue gas heat exchanger. The multi-directional folding plate assembly and the delta wings of the dust flow distribution unit 80 can be made of wear-resistant alloy materials. In addition, in special and narrow applications, the dust flow distribution unit 80 can also adopt a porous plate or a structure combining a porous plate and a guide plate, which can also achieve airflow uniformity.

[0062] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. Flue gas heat exchanger, characterized in that: The heat exchange module (30) comprises a plurality of rows of heat exchange tube assemblies (303), wherein one row of the heat exchange tube assemblies (303) comprises a plurality of heat exchange tube assemblies (303) arranged in sequence along a first direction; one heat exchange tube assembly (303) comprises a heat pipe (303b) and an outer sleeve (303a), a portion of each heat pipe (303b) is inserted into the corresponding outer sleeve (303a), both ends of the outer sleeve (303a) are sealed and connected to the heat pipe (303b), and cooling water can flow between the inner wall of the outer sleeve (303a) and the outer wall of the corresponding heat pipe (303b); in each row of the heat exchange tube assemblies (303), the plurality of outer sleeves (303a) are connected alternately up and down in sequence along the first direction; The flue gas heat collector comprises a shell (102), the shell (102) having an inlet smoke box (101) and an outlet smoke box (103), the upper part of the heat pipe (303b) is located above the shell (102), and the lower part of the heat pipe (303b) is located inside the shell (102); The heat exchange module (30) further comprises an inlet pipe (301) and an outlet pipe (302); each row of the heat exchange tube assemblies (303) comprises end heat exchange tube assemblies respectively located at two ends of the first direction; the outer sleeves (303a) of all the end heat exchange tube assemblies located at one end of the multiple rows of heat exchange tube assemblies (303) are connected to the inlet pipe (301), and the outer sleeves (303a) of all the end heat exchange tube assemblies (303) located at the other end are connected to the outlet pipe (302).

2. The flue gas heat exchanger according to claim 1, characterized in that: Both ends of the heat pipe (303b) and the outer sleeve (303a) are airtightly welded.

3. The flue gas heat exchanger according to claim 2, characterized in that: Both ends of the outer sleeve (303a) are extruded conical closing structures, and the inner diameter of the conical closing structure is equal to or slightly larger than the outer diameter of the heat pipe (303b).

4. The flue gas heat exchanger according to any one of claims 1 to 3, characterized in that: The flue gas heat exchanger comprises a heat exchange portion, the heat exchange portion comprises at least one row of the heat exchange modules (30), each row of the heat exchange modules (30) comprises at least one heat exchange module (30); the heat exchange modules (30) in each row of the heat exchange modules (30) are arranged along a second direction perpendicular to the first direction, and multiple rows of heat exchange modules (30) are arranged along the first direction.

5. The flue gas heat exchanger according to claim 4, characterized in that: The flue gas flows along the first direction, and the flow direction is opposite to the overall flow direction of the cooling water in a row of the heat exchange tube assemblies (303).

6. The flue gas heat exchanger according to claim 4, characterized in that: The flue gas heat exchanger further comprises an inlet main pipe (601) and an outlet main pipe (602); the heat exchange section comprises a plurality of rows of heat exchange modules (30), the inlet pipes (301) of all the heat exchange modules (30) in the front row are connected to the inlet main pipe (601), the outlet pipes (302) of all the heat exchange modules (30) in the back row are connected to the outlet main pipe (602), and in adjacent rows of heat exchange modules (30), the inlet pipe (301) of one and the outlet pipe (302) of the other are connected in a one-to-one correspondence; or, the heat exchange section comprises a row of heat exchange modules (30), the inlet pipes (301) of all the heat exchange modules (30) are connected to the inlet main pipe (601), and the outlet pipes (302) of all the heat exchange modules (30) are connected to the outlet main pipe (602).

7. The flue gas heat exchanger according to any one of claims 1 to 3, characterized in that: The heat pipe (303b) and the outer sleeve (303a) are arranged at an angle.

8. The flue gas heat exchanger according to claim 7, characterized in that: The tilt angle is 0-15 degrees.

9. The flue gas heat exchanger according to any one of claims 1 to 3, characterized in that: The heat exchange module (30) further comprises a plurality of grooved partitions (304), each of the grooved partitions (304) extending along the first direction; a plurality of heat pipes (303b) of a row of the heat exchange tube assemblies (303) penetrate a corresponding grooved partition (304), and a portion of the heat pipe (303b) located below the grooved partition (304) is its evaporation section (303b2).

10. The flue gas heat exchanger according to any one of claims 1 to 3, characterized in that: The flue gas heat exchanger further comprises an intelligent control unit (50), wherein the intelligent control unit (50) collects operating data of the flue gas heat exchanger in real time and compares and analyzes the data with the set benchmark data. When it is determined through intelligent calculation that the current operating data deviates significantly from the preset benchmark data, an equipment failure warning is issued.

11. The flue gas heat exchanger according to any one of claims 1 to 3, characterized in that: The flue gas heat extractor further comprises an online temperature measuring unit (40) for detecting the temperature of the condensation section (303b1) of the heat pipe (303b).

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