Soot blowing system for boiler heat exchanger of coal-fired unit

Abstract

The utility model discloses a coal-fired unit boiler heat exchanger soot blowing system which comprises a heat exchange shell, a first baffle is fixedly arranged in the heat exchange shell and divides the heat exchange shell into a first chamber body and a second chamber body, an air inlet pipeline is arranged at the upper end of the second chamber body, and an air outlet pipeline is arranged at the lower end of the second chamber body. The lower end of the second chamber body is provided with a gas inlet pipeline, the lower end of the second chamber body is provided with a gas outlet pipeline, a heat exchange pipe is fixed in the second chamber body, the gas inlet pipeline is connected with the first end of a first three-way valve, the second end and the third end of the first three-way valve are connected with a tail gas inlet pipeline and a soot blowing pipeline respectively, and the soot blowing pipeline is provided with a pump machine. The soot blowing pipeline is additionally arranged, the first three-way valve is regularly adjusted according to the actual use condition of the coal-fired unit, so that the soot blowing pipeline is communicated with the air inlet pipeline, the pump is used for providing air inlet power, blowing gas with low dust content is introduced into the heat exchange shell, the outer side of the heat exchange pipe is regularly blown, soot accumulation is avoided, and the heat exchange efficiency of the heat exchange pipe is guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of coal-fired equipment, in particular to a soot blowing system for a heat exchanger of a boiler of a coal-fired unit. Background Art

[0002] Coal-fired units refer to coal-fired power generation units, whose working principle is to convert the heat energy generated by coal combustion into electrical energy through power generation power devices (power plant boilers, steam turbines and generators and their auxiliary devices, etc.). During the use of coal-fired units, the heat generated by the boiler is not only used for power generation, but also part of the heat is released with the exhaust gas, which causes a certain amount of energy waste.

[0003] At present, in order to solve the energy waste problem caused by the energy carried by boiler exhaust gas, a heat exchanger is usually used to recover the heat of the exhaust gas. The heat exchanger commonly uses a heat exchange tube, and water and other media are passed through the heat exchange tube. The boiler exhaust gas passes through the outside of the heat exchange tube to exchange heat with the medium in the heat exchange tube, thereby recovering the energy carried by the boiler exhaust gas. However, the boiler uses coal as fuel, and there is a large amount of soot in its exhaust gas. During the heat exchange process, some soot will inevitably accumulate on the side wall of the heat exchange tube. As the use time increases, a certain thickness of ash layer will be formed on the outside of the heat exchange tube. This ash layer will greatly reduce the heat exchange efficiency of the heat exchange tube and affect the energy recovery of the boiler exhaust gas. Utility Model Content

[0004] The utility model aims to provide a soot blowing system for a coal-fired unit boiler heat exchanger, which adds a soot blowing pipeline and can regularly introduce high-pressure airflow into a heat exchange shell through the soot blowing pipeline to achieve timely removal of dust accumulation on the outside of the heat exchange tube, avoid the formation of a dust accumulation layer, and ensure the heat exchange efficiency of the heat exchange tube.

[0005] In order to achieve the above-mentioned purpose, the utility model provides a soot blowing system for a coal-fired unit boiler heat exchanger, and the technical scheme adopted is as follows:

[0006] A sootblowing system for a heat exchanger of a coal-fired unit boiler comprises a heat exchange shell, wherein a first baffle is fixedly arranged in the heat exchange shell, the first baffle divides the heat exchange shell into a first chamber body and a second chamber body, a second baffle is arranged in the first chamber body, one end of the second baffle is connected to the inner side wall of the heat exchange shell, and the other end thereof is connected to the second baffle, the second baffle divides the first chamber body into a first upper chamber body and a first lower chamber body, the first upper chamber body is connected to a water inlet pipe, the first lower chamber body is connected to a water outlet pipe, an air inlet pipe is arranged at the upper end of the second chamber body, and an air outlet pipe is arranged at the lower end of the second chamber body, a heat exchange pipe is fixed in the second chamber body, one end of the heat exchange pipe is communicated with the first upper chamber body, and the other end thereof is communicated with the first lower chamber body, the air inlet pipe is connected to a first end portion of a first three-way valve, the second end portion and the third end portion of the first three-way valve are respectively connected to an exhaust gas inlet pipe and a sootblowing pipe, and a pump is arranged on the sootblowing pipe.

[0007] Furthermore, a plurality of air flow baffles are staggeredly arranged in the second chamber.

[0008] Furthermore, a lifting lug is fixed to the upper end of the outer side of the heat exchange shell.

[0009] Furthermore, the lifting lug is provided in plurality.

[0010] Furthermore, a support assembly is provided at the lower end of the outer side of the heat exchange shell.

[0011] Furthermore, the support assembly includes two L-shaped support bases.

[0012] Furthermore, the air outlet duct is connected to the air inlet end of the dust collector.

[0013] Furthermore, a second three-way valve is provided at the air outlet end of the dust collector, and the second three-way valve is respectively connected to the flue gas duct and the purge air duct, and the purge air duct is connected to the soot blowing duct.

[0014] The beneficial effect of the utility model is as follows: according to the soot blowing system of the boiler heat exchanger of the coal-fired unit of the utility model, by adding a soot blowing pipe, according to the actual use of the coal-fired unit, the first three-way valve is regularly adjusted so that the soot blowing pipe is connected with the air intake pipe, and the pump is used to provide air intake power, and low-dust purge gas is introduced into the heat exchange shell, and the outside of the heat exchange tube is regularly purged to avoid dust accumulation and ensure the heat exchange efficiency of the heat exchange tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the specific implementation of the utility model or the technical solution in the prior art, the following is a brief introduction to the drawings required for the specific implementation or the prior art description. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, each element or part is not necessarily drawn according to the actual scale.

[0016] Figure 1 A partial cross-sectional structural diagram of a soot blowing system for a boiler heat exchanger of a coal-fired unit according to an embodiment of the utility model is shown.

[0017] Figure 2 A partial cross-sectional structural diagram of a soot blowing system of a boiler heat exchanger of a coal-fired unit according to an embodiment of the utility model is shown when a dust collector is provided.

[0018] In the figure, 1 is a heat exchange shell, 101 is a first chamber body, 1011 is a first upper chamber body, 1012 is a first lower chamber body, 102 is a second chamber body, 2 is a first baffle, 3 is a second baffle, 4 is a water inlet pipe, 5 is a water outlet pipe, 6 is an air inlet pipe, 7 is an air outlet pipe, 8 is a heat exchange pipe, 9 is a first three-way valve, 10 is an exhaust gas inlet pipe, 11 is a soot blowing pipe, 12 is a pump, 13 is an air flow baffle, 14 is a lifting ear, 15 is a support assembly, 1501 is an L-shaped support base, 16 is a dust collector, 17 is a second three-way valve, 18 is a flue gas pipe, and 19 is a purge pipe. DETAILED DESCRIPTION

[0019] The following describes the implementation of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0020] In the description of the present invention, unless otherwise specified, "multiple" means two or more; the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third" and the like are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0021] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] The specific implementation of the utility model is further described in detail below in conjunction with the drawings and embodiments.

[0023] The utility model provides a soot blowing system for a coal-fired unit boiler heat exchanger, such as Figure 1 As shown, the soot blowing system of the heat exchanger of the coal-fired unit boiler includes a heat exchange shell 1, a first baffle 2 is fixedly arranged in the heat exchange shell 1, the first baffle 2 divides the heat exchange shell 1 into a first chamber 101 and a second chamber 102, a second baffle 3 is arranged in the first chamber 101, one end of the second baffle 3 is connected to the inner side wall of the heat exchange shell 1, and the other end is connected to the second baffle 3, the second baffle 3 divides the first chamber 101 into a first upper chamber 1011 and a first lower chamber 1012, the first upper chamber 1011 is connected to a water inlet pipe 4, the first lower chamber body 1012 is connected to the water outlet pipe 5, the upper end of the second chamber body 102 is provided with an air inlet pipe 6, the lower end of the second chamber body 102 is provided with an air outlet pipe 7, a heat exchange tube 8 is fixed in the second chamber body 102, one end of the heat exchange tube 8 is connected to the first upper chamber body 1011, and the other end thereof is connected to the first lower chamber body 1012, the air inlet pipe 6 is connected to the first end of the first three-way valve 9, the second end and the third end of the first three-way valve 9 are respectively connected to the exhaust gas inlet pipe 10 and the soot blowing pipe 11, and the soot blowing pipe 11 is provided with a pump 12.

[0024] During specific implementation, cold water is delivered through the water inlet pipe 4, the cold water first enters the first upper chamber body 1011, and then enters the heat exchange tube 8. When the heat exchange process is carried out, the first three-way valve 9 is adjusted to connect the exhaust gas inlet pipe 10 with the air inlet pipe 6. The exhaust gas inlet pipe 10 is used to deliver the exhaust gas (flue gas) generated by the boiler to the second chamber body 102 through the air inlet pipe 6. The exhaust gas and the heat exchange tube 8 in the second chamber body 102 are heat-exchanged, and the residual heat is used to heat the cold water in the heat exchange tube 8 to form water vapor. The water vapor is discharged through the water outlet pipe 5 set in the first lower chamber body 1012, and the exhaust gas after the heat exchange is completed is discharged through the air outlet pipe 7, thereby realizing the heat exchange process.

[0025] When the soot blowing process is being carried out, the first three-way valve 9 is adjusted so that the soot blowing pipe 11 is connected to the air inlet pipe 6, and the pump 12 is turned on to pump the purge gas through the soot blowing pipe 11. The purge gas includes but is not limited to air with a PM of 2.5. The purge gas forms a high-pressure purge gas under the action of the pump 12 and is pumped into the second chamber 102. The high-pressure purge gas with low dust content is used to purge the outer wall of the heat exchange tube 8 to remove the dust that may remain on the outer wall of the heat exchange tube 8, avoid the formation of a dust layer, and ensure the heat exchange efficiency of the heat exchange tube. When the soot blowing process is being carried out, the water inlet pipe 4 can suspend the supply of cold water.

[0026] It should be noted that when one heat exchange shell 1 is connected to one boiler, the boiler connected to it should be shut down during the soot blowing process. When the boiler is connected to multiple heat exchange shells 1, at least one heat exchange shell 1 should be ensured to be in the heat exchange process.

[0027] It should be noted that the heat exchange medium in the above example is water, which can come from tap water in a municipal pipeline, and the heated water can be used as domestic water or industrial water in the factory. It can be understood that the heat exchange medium can also be other fluid media that need to be heated. This embodiment is only an example here, and is not a limitation of the present invention.

[0028] In some embodiments, Figure 1 As shown, a plurality of air flow baffles 13 are staggeredly arranged in the second chamber body 102, and the contact area between the exhaust gas and the heat exchange pipe 8 is increased by the plurality of staggered air flow baffles 13, thereby ensuring the heat exchange efficiency. The air flow baffles 13 can be fixedly installed on the inner wall of the second chamber body 102.

[0029] In some embodiments, Figure 1 As shown, a lifting lug 14 is fixed to the upper end of the outer side of the heat exchange shell 1. The provision of the lifting lug 14 is optional, and its purpose is to cooperate with the corresponding lifting equipment to facilitate the position adjustment of the heat exchange shell 1. The lifting lug 14 can be set to multiple as needed, such as two, three, etc., and is determined according to the specific length size of the heat exchange shell 1, and this embodiment is not specifically limited here.

[0030] In some embodiments, Figure 1 As shown, a support assembly 15 is provided at the lower end of the outer side of the heat exchange shell 1, and the support assembly 15 plays a role in supporting the heat exchange shell 1 as a whole. As an example only, the support assembly 15 includes two L-shaped support bases 1501.

[0031] In some embodiments, Figure 2As shown, the outlet pipe 7 is connected to the air inlet end of the dust collector 16. The dust collector 16 can be a bag dust collector or a cyclone dust collector. The exhaust gas after heat exchange can be greatly reduced in smoke content after being processed by the dust collector.

[0032] In a specific embodiment, if Figure 2 As shown, a second three-way valve 17 is provided at the air outlet of the dust collector 16 , and the second three-way valve 17 is respectively connected to a flue gas duct 18 and a purge duct 19 , and the purge duct 19 is connected to the soot blowing duct 11 .

[0033] When the heat exchange process is performed, the second three-way valve 17 should be adjusted to connect the flue gas duct 18 to the gas outlet end of the dust collector 16, and the flue gas treated by the dust collector enters the exhaust gas treatment process through the flue gas duct 18.

[0034] When the soot blowing process is being carried out, the second three-way valve 17 should be adjusted to connect the purge duct 19 to the air outlet of the dust collector 16, that is, the flue gas treated by the dust collector passes through the purge duct 19 and then passes through the soot blowing duct 11, and after being pressurized by the pump 12, the tail gas after dust removal is used as the purge gas for purge. The advantage of using the tail gas after dust removal as the purge gas is that although the purge gas has undergone heat exchange, it still has a higher temperature than air, so that during the purge process, although the temperature in the second chamber 102 will drop, the drop is much lower than the drop when air is used as the purge gas for purge. This method can reduce part of the heat loss caused by the soot blowing process while ensuring the purge effect, and ensure the heat exchange efficiency of the overall purge system.

[0035] The above implementation modes are only used to illustrate the present invention, but not to limit the present invention. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions also belong to the scope of the present invention. The scope of patent protection of the present invention should be limited by the claims.

Claims

1. A soot blowing system for a coal-fired unit boiler heat exchanger, characterized in that: It includes a heat exchange shell, a first baffle is fixedly arranged in the heat exchange shell, the first baffle divides the heat exchange shell into a first chamber body and a second chamber body, a second baffle is arranged in the first chamber body, one end of the second baffle is connected to the inner side wall of the heat exchange shell, and the other end thereof is connected to the second baffle, the second baffle divides the first chamber body into a first upper chamber body and a first lower chamber body, the first upper chamber body is connected to a water inlet pipe, the first lower chamber body is connected to a water outlet pipe, an air inlet pipe is arranged at the upper end of the second chamber body, and an air outlet pipe is arranged at the lower end of the second chamber body, a heat exchange pipe is fixed in the second chamber body, one end of the heat exchange pipe is communicated with the first upper chamber body, and the other end thereof is communicated with the first lower chamber body, the air inlet pipe is connected to a first end of a first three-way valve, the second end and the third end of the first three-way valve are respectively connected to an exhaust gas inlet pipe and a soot blowing pipe, and a pump is arranged on the soot blowing pipe.

2. The soot blowing system for a coal-fired unit boiler heat exchanger according to claim 1, characterized in that: A plurality of air flow baffles are staggeredly arranged in the second chamber.

3. The soot blowing system for a coal-fired unit boiler heat exchanger according to claim 1, characterized in that: A lifting lug is fixed to the upper end of the outer side of the heat exchange shell.

4. The soot blowing system for a coal-fired unit boiler heat exchanger according to claim 3, characterized in that: The lifting lugs are provided in plurality.

5. The soot blowing system for a coal-fired unit boiler heat exchanger according to claim 1, characterized in that: A support assembly is arranged at the lower end of the outer side of the heat exchange shell.

6. The soot blowing system for a coal-fired unit boiler heat exchanger according to claim 5, characterized in that: The support assembly includes two L-shaped support bases.

7. The soot blowing system for a coal-fired unit boiler heat exchanger according to claim 1, characterized in that: The air outlet duct is connected to the air inlet end of the dust collector.

8. The soot blowing system for a coal-fired unit boiler heat exchanger according to claim 7, characterized in that: A second three-way valve is provided at the air outlet end of the dust collector, and the second three-way valve is respectively connected to the flue gas duct and the purge air duct, and the purge air duct is connected to the soot blowing duct.

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