Heat exchanger for low-low-temperature coal economizer

Abstract

The heat exchanger comprises a mounting shell, a plurality of heat exchange mechanisms are distributed and mounted on the inner side of the mounting shell at equal intervals, and a linkage ash removal mechanism is mounted on the outer side of each heat exchange mechanism; a cleaning mechanism is mounted on the outer side of the linkage dust removal mechanism, the cleaning mechanism comprises a mounting plate, and a mounting ring is rotationally mounted on the inner side of the mounting plate; a protruding plate is fixed to the lower side of the mounting plate, the inner side of the protruding plate is in threaded connection with a driving rod, and one end of the driving rod is connected with the output end of the second motor. Thick dust adhering to the outer side of the heat exchange mechanism is cleaned through the cleaning strips, thin dust, not cleaned by the cleaning strips, on the outer surface of the heat exchange mechanism is cleaned through the cleaning blocks, the outer surface of the heat exchange mechanism is always in a smooth and clean state, and it is avoided that smoke and dust affect the heat exchange efficiency; and meanwhile, the outer side of the heat exchange mechanism can be prevented from being abraded due to direct scraping of the adhesion block.

Description

Technical Field

[0001] The present application relates to the technical field of low-temperature economizers, and in particular to a heat exchanger for low-temperature economizers. Background Art

[0002] As a standard configuration of coal-fired boilers in recent years, low-temperature economizers are one of the most common flue gas heat exchangers in coal-fired boilers. In common low-temperature economizer flue gas heat exchangers, the flue gas heat exchanger is composed of heat exchange modules with similar array structures. After the flue gas flows into the flue gas heat exchanger, the dust particles carried in the flue gas change from the molten state in the furnace to the solid state due to the drop in flue gas temperature, which causes the dust particles to adhere to the outside of the heat exchange pipe, thereby affecting the heat exchange efficiency.

[0003] The prior art discloses a low-temperature economizer system and a working method thereof that can prevent ash blockage. By regularly changing the position of the arc-shaped baffle group at the upper and lower parts of the Y-shaped flue, the flue gas inlet direction of the heat exchanger is changed, and the leeward side of the heat exchanger exhaust pipe, which is prone to ash accumulation, is converted into the windward side. This can not only effectively prevent ash accumulation on the heat exchanger exhaust pipe, but also play a role in guiding the flue gas, thereby preventing local wear of the heat exchanger.

[0004] The outer side of the heat exchanger pipe used in the prior art is in direct contact with the flue gas, which inevitably causes dust particles in the flue gas to adhere to the outer side of the heat exchange pipe, thereby increasing the thickness of the heat exchanger pipe and further affecting the heat exchange efficiency. Some prior arts propose a technology for cleaning the outer side of the heat exchange pipe, but the cleaning effect achieved is a hard cleaning of the heat exchanger surface, which can easily cause greater wear on the heat exchanger surface. Summary of the invention

[0005] To this end, the present application provides a heat exchanger for a low-temperature economizer to solve the problem of hard cleaning of the heat exchanger surface in the prior art, which easily leads to significant wear on the heat exchanger surface.

[0006] In order to achieve the above objectives, this application provides the following technical solutions:

[0007] A heat exchanger for a low-temperature economizer, comprising:

[0008] A mounting shell is provided, wherein a plurality of heat exchange mechanisms are evenly spacedly mounted on the inner side of the mounting shell, and a connecting and cleaning mechanism is installed on the outer side of the heat exchange mechanism, wherein the connecting and cleaning mechanism comprises a connecting wheel and a cleaning strip, wherein the connecting wheel monomers are rotatably mounted on the two ends of the heat exchange mechanism, and a plurality of cleaning strips are evenly spacedly fixed on the inner side of the connecting wheel, wherein the connecting wheel monomers are meshedly connected, wherein any of the connecting wheels is meshedly connected with a stepped wheel mounted on the upper side of the mounting shell, wherein one side of the stepped wheel is meshedly connected with a driving wheel, and the driving wheel is connected with the output end of the first motor;

[0009] A cleaning mechanism is installed on the outer side of the connecting cleaning mechanism, and the cleaning mechanism includes a mounting plate, a mounting ring is rotatably mounted on the inner side of the mounting plate, and a cleaning block is installed on the inner side of the mounting ring, the inner side of the cleaning block is fitted with the outer surface of the heat exchange mechanism, and the cleaning block and the cleaning strips are staggered at equal angles;

[0010] A protruding plate is fixed on the lower side of the mounting plate, an active rod is threadedly connected to the inner side of the protruding plate, and one end of the active rod is connected to the output end of the second motor.

[0011] Optionally, the inner side of the mounting plate is further provided with exhaust holes which are staggered with the mounting ring.

[0012] Optionally, the arc angle of the mounting ring is greater than the arc angle of the cleaning strip.

[0013] Optionally, a lower protruding shell corresponding to the protruding plate is installed on the lower side of the mounting shell, a positioning rod is fixedly installed on the inner side of the lower protruding shell, a smoke circulation outlet pipe is installed at one end of the lower side of the active rod, and a smoke circulation inlet pipe is installed at the other end of the lower side of the active rod, an upper protruding shell is installed on the upper side of the mounting shell, a smoke inlet pipe is installed at one end of the upper side of the upper protruding shell, and a smoke outlet pipe is installed at the other end of the upper side of the upper protruding shell.

[0014] Optionally, the smoke outlet pipe and the smoke circulation inlet pipe are centrally symmetrically arranged with respect to the center of the mounting shell, and the smoke inlet pipe and the smoke circulation outlet pipe are centrally symmetrically arranged with respect to the center of the mounting shell.

[0015] Optionally, grooves are provided at equal angles on the inner side of the cleaning strips, and the grooves provided in adjacent cleaning strips are staggered.

[0016] Optionally, the heat exchange mechanism comprises a heat exchange tube, and a guide bar is installed on the inner side of the heat exchange tube, and the guide bar is arranged in a spiral shape.

[0017] Optionally, the longitudinal section of the guide strip is triangular, and an arc-shaped groove structure is provided on the inner side of the guide strip.

[0018] Compared with the prior art, this application has at least the following beneficial effects:

[0019] 1. Use the cleaning strip to clean the thick dust adhering to the outside of the heat exchange mechanism, and then use the cleaning block to clean the thin dust on the outer surface of the heat exchange mechanism that has not been cleaned by the cleaning strip, so that the outer surface of the heat exchange mechanism is always smooth and clean, avoiding the flue gas dust from affecting the heat exchange efficiency, and avoiding the wear on the outer side of the heat exchange mechanism caused by directly scraping off the adhesion block.

[0020] 2. Through the meshing connection between the connecting wheel monomers, any of the connecting wheels is meshed with the stepped wheel installed on the upper side of the installation shell, so that the outer surfaces of all heat exchange mechanisms are installed with corresponding connecting cleaning mechanisms and cleaning blocks for cleaning.

[0021] 3. The smoke inlet pipe, smoke outlet pipe, smoke circulation outlet pipe and smoke circulation outlet pipe are used to make the smoke after heat exchange circulate twice in the installation shell. While reusing the heat contained in the smoke, the smoke on the left side of the installation shell can be pressurized to increase the flow rate of the smoke in the installation shell. Finally, the smoke is discharged from the smoke outlet pipe to make the smoke secondary. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more intuitively illustrate the prior art and the present application, exemplary drawings are given below. It should be understood that the specific shapes and structures shown in the drawings should not generally be regarded as limiting conditions for implementing the present application; for example, those skilled in the art are capable of easily making conventional adjustments or further optimizations to the addition / reduction / attribution division, specific shapes, positional relationships, connection methods, dimensional ratios, etc. of certain units (components) based on the technical concepts and exemplary drawings disclosed in the present application.

[0023] Figure 1 A schematic diagram of a front cross-sectional structure of a heat exchanger for a low-temperature economizer provided in one embodiment of the present application;

[0024] Figure 2 For this application Figure 1 The enlarged structural diagram at A in the middle;

[0025] Figure 3 For this application Figure 1 The enlarged structural diagram at B in the middle;

[0026] Figure 4 A schematic diagram of a side cross-sectional structure of a heat exchanger for a low-temperature economizer provided in one embodiment of the present application;

[0027] Figure 5 A schematic diagram of a side cross-sectional structure of a cleaning block and a cleaning strip connected to a heat exchanger for a low-temperature economizer provided in one embodiment of the present application;

[0028] Figure 6 An overall schematic diagram of a connection and cleaning mechanism for a heat exchanger for a low-temperature economizer provided in one embodiment of the present application;

[0029] Figure 7 An overall cross-sectional schematic diagram of a heat exchange mechanism of a heat exchanger for a low-temperature economizer provided in one embodiment of the present application;

[0030] Figure 8A schematic diagram of flue gas flow in a heat exchanger for a low-temperature economizer is provided as an embodiment of the present application.

[0031] Description of reference numerals:

[0032] 1. Install the shell; 2. Heat exchange mechanism; 201. Heat exchange tube; 202. Guide strip; 3. Cleaning mechanism; 301. Mounting plate; 302. Mounting ring; 303. Cleaning block; 304. Exhaust hole; 4. Connecting cleaning mechanism; 401. Connecting wheel; 402. Cleaning strip; 403. Groove; 5. First motor; 6. Driving wheel; 7. Step wheel; 8. Upper protruding shell; 9. Smoke inlet pipe; 10. Smoke outlet pipe; 11. Lower protruding shell; 12. Smoke circulation outlet pipe; 13. Smoke circulation inlet pipe; 14. Driving rod; 15. Positioning rod; 16. Protruding plate. DETAILED DESCRIPTION

[0033] The present application is further described below in detail through specific embodiments in conjunction with the accompanying drawings.

[0034] A heat exchanger for a low-temperature economizer provided by the present invention comprises a mounting shell 1, a plurality of heat exchange mechanisms 2 are evenly spacedly mounted on the inner side of the mounting shell 1, a connecting and cleaning mechanism 4 is mounted on the outer side of the heat exchange mechanism 2, wherein the connecting and cleaning mechanism 4 comprises a connecting wheel 401 and a cleaning strip 402, the connecting wheel 401 monomers are rotatably mounted on the two ends of the heat exchange mechanism 2, and a plurality of cleaning strips 402 are evenly spacedly fixed on the inner side of the connecting wheel 401, the connecting wheel 401 monomers are meshedly connected, any connecting wheel 401 is meshedly connected with a stepped wheel 7 mounted on the upper side of the mounting shell 1, one side of the stepped wheel 7 is meshedly connected with a driving wheel 6, and the driving wheel 6 is connected with the output end of the first motor 5;

[0035] Specifically, when smoke dust adheres to the outer surface of the heat exchange mechanism 2, the first motor 5 is started to drive the driving wheel 6 to rotate, so that the driving wheel 6 drives the stepped wheel 7 to rotate, thereby rotating any connecting wheel 401 meshed with the stepped wheel 7, and then driving all the connecting wheels 401 to rotate, so that the cleaning strip 402 scrapes off the dust adhered to the outer side of the heat exchange mechanism 2;

[0036] However, in order to increase the heat exchange efficiency, the heat exchange mechanism 2 is usually longer, and the middle part of a single cleaning strip 402 will be deformed, thereby affecting the cleaning effect of the cleaning strip 402 in the middle part of the heat exchange mechanism 2, making it very easy for a thin layer of dust to adhere to the surface of the cleaning strip 402. Therefore, a cleaning mechanism 3 is installed on the outer side of the connecting cleaning mechanism 4, and the cleaning mechanism 3 includes a mounting plate 301, a mounting ring 302 is rotatably mounted on the inner side of the mounting plate 301, and a cleaning block 303 is installed on the inner side of the mounting ring 302, the inner side of the cleaning block 303 is arranged in contact with the outer surface of the heat exchange mechanism 2, and the cleaning block 303 and the cleaning strip 402 are staggered at equal angles;

[0037] The inner side of the mounting plate 301 is also provided with exhaust holes 304 arranged alternately with the mounting ring 302, so as to facilitate the conduction of smoke and avoid the mounting plate 301 from hindering the flow of smoke;

[0038] The arc angle of the mounting ring 302 is greater than the arc angle of the cleaning strip 402, so that the coverage area of ​​the cleaning strip 402 on the outside of the heat exchange mechanism 2 is reduced, so that when the smoke enters, the smoke can contact the outer surface of the heat exchange mechanism 2 as much as possible;

[0039] A protruding plate 16 is fixed to the lower side of the mounting plate 301, and an active rod 14 is threadedly connected to the inner side of the protruding plate 16, and one end of the active rod 14 is connected to the output end of the second motor, so that when the second motor is started, the protruding plate 16 can drive the mounting plate 301 to move. In order to prevent the protruding plate 16 from tilting when moving, a positioning rod 15 arranged on one side of the active rod 14 is also slidably connected to the inner side of the protruding plate 16;

[0040] Specifically, when the cleaning bar 402 starts to rotate, it drives the cleaning block 303 to rotate, and the second motor is started to rotate the active rod 14, so that the protruding plate 16 drives the mounting plate 301 to slide on the outer surface of the heat exchange mechanism 2. At this time, the cleaning bar 402 rotates to drive the cleaning block 303 to rotate, and the mounting plate 301 drives the cleaning block 303 to slide on the outer side of the heat exchange mechanism 2, so that the cleaning block 303 can move in a spiral shape on the outer side of the heat exchange mechanism 2;

[0041] Furthermore, during the rotation of the cleaning strip 402, the thicker dust on the outer surface of the heat exchange mechanism 2 is cleaned. Then, during the spiral movement of the mounting plate 301, the thinner dust on the outer surface of the heat exchange mechanism 2 that has not been cleaned by the cleaning strip 402 is cleaned, so that the outer surface of the heat exchange mechanism 2 is always smooth and clean, thereby preventing the flue gas dust from affecting the heat exchange efficiency.

[0042] A lower protruding shell 11 corresponding to the protruding plate 16 is installed on the lower side of the installation shell 1, wherein the positioning rod 15 is fixedly installed on the inner side of the lower protruding shell 11, a smoke circulation outlet pipe 12 is installed on one end of the lower side of the active rod 14, and a smoke circulation inlet pipe 13 is installed on the other end of the lower side of the active rod 14, an upper protruding shell 8 is installed on the upper side of the installation shell 1, and a smoke inlet pipe 9 is installed on one end of the upper side of the upper protruding shell 8, and a smoke outlet pipe 10 is installed on the other end of the upper side of the upper protruding shell 8, wherein the smoke outlet pipe 10 and the smoke circulation inlet pipe 13 are centrally symmetrically arranged about the center of the installation shell 1, and the smoke inlet pipe 9 and the smoke circulation outlet pipe 12 are centrally symmetrically arranged about the center of the installation shell 1;

[0043] In a specific embodiment, Figure 8As shown in the figure, after the water is introduced into the heat exchange mechanism 2, the hot flue gas is introduced into the installation shell 1 from the flue gas inlet pipe 9 in the upper left corner, wherein the diameter of the flue gas inlet pipe 9 is relatively large, which is convenient for the introduction of a large amount of flue gas. After the flue gas contacts the outer surface of the heat exchange mechanism 2, heat exchange is realized, and then the flue gas after the heat exchange is discharged from the flue gas circulation outlet pipe 12 installed on the lower side of the lower protruding shell 11, and then the flue gas after the heat exchange is continued to be introduced into the installation shell 1 from the flue gas circulation inlet pipe 13. While reusing the heat contained in the flue gas, the flue gas on the left side of the installation shell 1 can also be pressurized, so that the flow speed of the flue gas in the installation shell 1 is increased, and finally the smoke is discharged outward from the smoke outlet pipe 10, so that the smoke can be reused for a second time.

[0044] The inner side of the cleaning strip 402 is provided with grooves 403 at equal angles, and the grooves 403 provided in adjacent cleaning strips 402 are arranged in a staggered manner, so that the cleaning strips 402 can gradually clean the dust adhering to the outer surface of the heat exchange mechanism 2 during the rotation process, thereby avoiding the cleaning strips 402 from having too heavy a single cleaning load;

[0045] The heat exchange mechanism 2 includes a heat exchange tube 201, and a guide strip 202 is installed on the inner side of the heat exchange tube 201. The guide strip 202 is spirally arranged, and the longitudinal section of the guide strip 202 is triangularly arranged. An arc-shaped groove structure is provided on the inner side of the guide strip 202. When flue gas is conducted in the heat exchange tube 201, the flue gas moves along the outer surface of the guide strip 202, and part of the flue gas is guided by the arc-shaped groove structure provided in the guide strip 202, thereby generating a movement in the opposite direction of the flue gas flow, thereby reducing the flow velocity of the water in the heat exchange mechanism 2, thereby increasing the heat exchange effect.

[0046] The technical features of the above embodiments may be arbitrarily combined (as long as there is no contradiction in the combination of these technical features). To make the description concise, not all possible combinations of the technical features in the above embodiments are described; these embodiments that are not explicitly written should also be considered to be within the scope of this specification.

Claims

1. A heat exchanger for a low temperature economizer, characterized in that: include: A mounting shell (1), wherein a plurality of heat exchange mechanisms (2) are evenly spacedly mounted on the inner side of the mounting shell (1), and a connecting and cleaning mechanism (4) is mounted on the outer side of the heat exchange mechanism (2), wherein the connecting and cleaning mechanism (4) comprises a connecting wheel (401) and a cleaning strip (402), wherein the connecting wheel (401) is rotatably mounted on the two ends of the heat exchange mechanism (2), and a plurality of cleaning strips (402) are evenly spacedly fixed on the inner side of the connecting wheel (401), wherein the connecting wheel (401) is meshingly connected to each other, and any of the connecting wheels (401) is meshingly connected to a stepped wheel (7) mounted on the upper side of the mounting shell (1), and one side of the stepped wheel (7) is meshingly connected to a driving wheel (6), and the driving wheel (6) is connected to the output end of the first motor (5); A cleaning mechanism (3) is installed on the outer side of the connecting cleaning mechanism (4), and the cleaning mechanism (3) comprises a mounting plate (301), a mounting ring (302) is rotatably mounted on the inner side of the mounting plate (301), and a cleaning block (303) is installed on the inner side of the mounting ring (302), the inner side of the cleaning block (303) is arranged in close contact with the outer surface of the heat exchange mechanism (2), and the cleaning block (303) and the cleaning strips (402) are arranged in an equiangular and staggered manner; A protruding plate (16) is fixed to the lower side of the mounting plate (301), an active rod (14) is threadedly connected to the inner side of the protruding plate (16), and one end of the active rod (14) is connected to the output end of the second motor.

2. A heat exchanger for a low-temperature economizer according to claim 1, characterized in that: The inner side of the mounting plate (301) is also provided with exhaust holes (304) arranged alternately with the mounting ring (302).

3. The heat exchanger for a low-temperature economizer according to claim 1, characterized in that: The arc angle of the mounting ring (302) is greater than the arc angle of the cleaning strip (402).

4. The heat exchanger for a low-temperature economizer according to claim 1, characterized in that: A lower protruding shell (11) corresponding to the protruding plate (16) is installed on the lower side of the installation shell (1), a positioning rod (15) is fixedly installed on the inner side of the lower protruding shell (11), a smoke circulation outlet pipe (12) is installed on one end of the lower side of the active rod (14), and a smoke circulation inlet pipe (13) is installed on the other end of the lower side of the active rod (14), an upper protruding shell (8) is installed on the upper side of the installation shell (1), a smoke inlet pipe (9) is installed on one end of the upper side of the upper protruding shell (8), and a smoke outlet pipe (10) is installed on the other end of the upper side of the upper protruding shell (8).

5. A heat exchanger for a low-temperature economizer according to claim 4, characterized in that: The smoke outlet pipe (10) and the smoke circulation inlet pipe (13) are centrally symmetrically arranged with respect to the center of the mounting shell (1), and the smoke inlet pipe (9) and the smoke circulation outlet pipe (12) are centrally symmetrically arranged with respect to the center of the mounting shell (1).

6. The heat exchanger for a low-temperature economizer according to claim 1, characterized in that: Grooves (403) are also provided at equal angles on the inner side of the cleaning strips (402), and the grooves (403) provided in adjacent cleaning strips (402) are arranged in a staggered manner.

7. The heat exchanger for a low-temperature economizer according to claim 1, characterized in that: The heat exchange mechanism (2) comprises a heat exchange tube (201), and a guide bar (202) is also installed on the inner side of the heat exchange tube (201), and the guide bar (202) is arranged in a spiral shape.

8. A heat exchanger for a low-temperature economizer according to claim 7, characterized in that: The longitudinal section of the guide bar (202) is triangular in shape, and an arc-shaped groove structure is provided on the inner side of the guide bar (202).

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