Efficient flue gas and air circulation bypass system for starting waste heat boiler

Abstract

The utility model relates to the technical field of waste heat boilers, and provides an efficient flue gas and air circulation bypass system for starting of a waste heat boiler, which is matched with the waste heat boiler and an ash bucket for use, the waste heat boiler is provided with a first radiation channel, a second radiation channel and a third radiation channel, and comprises a cyclone separator arranged on the outer side of the waste heat boiler, an inlet of the cyclone separator is communicated with a flue gas inlet of the second radiation channel, a flue gas outlet of the cyclone separator is communicated with a flue gas inlet of the third radiation channel through a first pipeline, a first flue gas baffle is installed on the first pipeline, and the flue gas outlet of the cyclone separator is further communicated with a flue gas outlet of the third radiation channel through a second pipeline. A second flue gas baffle plate is mounted on the second pipeline; and a slag discharge port of the cyclone separator is communicated with the ash bucket. According to the efficient flue gas and air circulation bypass system for starting the waste heat boiler, the temperature of main steam output by a superheater can rapidly reach a rated parameter when the boiler is just started.

Description

Technical Field

[0001] This utility model relates to the field of waste heat boiler technology, specifically to a high-efficiency flue gas circulation bypass system for starting up a waste heat boiler. Background Technology

[0002] For conventional waste heat boilers, such as Figure 1 As shown, the high-temperature flue gas generated by the incinerator sequentially enters the first radiant channel, second radiant channel, third radiant channel, and convective heating surface channel of the waste heat boiler. After exchanging heat with the superheater in the convective heating surface channel, it is discharged from the boiler. Simultaneously, ash hoppers are typically installed under the first, second, third radiant channels, and convective heating surface channels to collect ash. A fly ash treatment device is installed at the boiler's flue gas outlet to collect and treat the fly ash generated by the boiler.

[0003] However, current waste heat boilers have the following drawbacks: 1. Due to the characteristics of waste heat boilers, after new construction or renovation, the main steam temperature output from the superheater is generally low at the beginning of boiler startup, requiring the boiler to operate for a period of time before reaching rated parameters, thus reducing working efficiency. 2. Currently, for horizontally arranged waste heat boilers, fly ash is mainly discharged through ash hoppers to ash conveying equipment and then transported to a slag remover for solid waste treatment. The fly ash at the tail end of the waste heat boiler is solidified as hazardous waste after passing through flue gas purification equipment. Utility Model Content

[0004] In view of the deficiencies in the existing technology, the purpose of this utility model is to provide a high-efficiency flue gas circulation bypass system for starting up a waste heat boiler, so that the main steam temperature output by the superheater can quickly reach the rated parameters when the boiler is first started up, and the amount of fly ash at the tail of the boiler can be reduced.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a high-efficiency waste heat boiler start-up flue gas circulation bypass system, used in conjunction with a waste heat boiler and an ash hopper, wherein the waste heat boiler has a first radiation channel, a second radiation channel, and a third radiation channel, comprising:

[0006] A cyclone separator is installed outside the waste heat boiler. The inlet of the cyclone separator is connected to the flue gas inlet of the second radiant channel, and the flue gas outlet of the cyclone separator is connected to the flue gas inlet of the third radiant channel through a first pipe. A first flue gas baffle is installed on the first pipe. The flue gas outlet of the cyclone separator is also connected to the flue gas outlet of the third radiant channel through a second pipe. A second flue gas baffle is installed on the second pipe. The ash discharge port of the cyclone separator is connected to the ash hopper.

[0007] Furthermore, the flue gas outlet of the cyclone separator is also connected to the flue gas outlet of the second radiation channel through a third pipe, and a third flue gas baffle is installed on the third pipe.

[0008] Furthermore, it also includes a shock wave cleaning assembly, which comprises four shock wave cleaners arranged at equal intervals along the circumference of the cyclone separator.

[0009] Furthermore, the number of shock wave cleaning components is 2-3, and the 2-3 shock wave cleaning components are arranged at equal intervals along the height direction of the cyclone separator.

[0010] Furthermore, it also includes an expansion joint, the inlet of which is connected to the flue gas inlet of the second radiation channel, and the outlet of which is connected to the inlet of the cyclone separator.

[0011] Furthermore, a butterfly valve is installed at the inlet of the cyclone separator.

[0012] The beneficial effects of this utility model are as follows: This utility model provides a high-efficiency waste heat boiler start-up flue gas circulation bypass system. By controlling the amount of flue gas entering the third radiation channel to participate in boiler heat exchange, the temperature of the flue gas entering the convection heating surface channel is increased. In this way, the temperature of the main steam in the superheater after heat exchange will increase rapidly and reach the rated parameters. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of an existing waste heat boiler;

[0014] Figure 2 It is a structural diagram of the utility model;

[0015] Figure 3 This is a schematic diagram of a cyclone separator.

[0016] Reference numerals: 10-Waste heat boiler, 11-First radiant channel, 12-Second radiant channel, 13-Third radiant channel, 14-Convection heating surface channel, 15-Superheater, 16-Ash hopper, 20-Cyclone separator, 21-First pipe, 22-First flue gas damper, 23-Second pipe, 24-Second flue gas damper, 25-Third pipe, 26-Third flue gas damper, 30-Ash cleaning assembly, 31-Ash cleaner, 40-Expansion joint, 50-Incinerator. Detailed Implementation

[0017] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.

[0018] In this application, unless otherwise expressly specified and limited, the terms "connection" and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0019] In the description of this application, it should be understood that the terms "longitudinal", "horizontal", "level", "top", "bottom", "upper", "lower", "inner" and "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0020] In addition, the terms "first," "second," etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. In the description of this utility model, "plurality" means more than two, unless otherwise specifically defined.

[0021] like Figure 2-Figure 3 As shown, this utility model provides a high-efficiency flue gas circulation bypass system for starting up a waste heat boiler, which is used in conjunction with the waste heat boiler 10 and the ash hopper 16. The waste heat boiler 10 has a first radiation channel 11, a second radiation channel 12, a third radiation channel 13 and a convection heating surface channel 14. A superheater 15 is installed in the convection heating surface channel 14. After heat exchange, the superheater 15 generates main steam. The above contents are all prior art, and the specific structure will not be described in detail here.

[0022] This system includes a cyclone separator 20, which is located outside the waste heat boiler 10. The inlet of the cyclone separator 20 is connected to the flue gas inlet of the second radiant channel 12. The flue gas outlet of the cyclone separator 20 is connected to the flue gas inlet of the third radiant channel 13 via a first pipe 21. A first flue gas baffle 22 is installed on the first pipe 21 to regulate the amount of flue gas entering the flue gas inlet of the third radiant channel 13. The flue gas outlet of the cyclone separator 20 is also connected to the flue gas outlet of the third radiant channel 13 via a second pipe 23. A second flue gas baffle 24 is installed on the second pipe 23 to regulate the amount of flue gas entering the flue gas outlet of the third radiant channel 13. The ash discharge port of the cyclone separator 20 is connected to the ash hopper 16.

[0023] The first flue gas damper 22 and the second flue gas damper 24 can be pneumatically or electrically controlled.

[0024] During operation, the high-temperature flue gas generated by the incinerator 50 sequentially enters the first radiant channel 11, the second radiant channel 12, the third radiant channel 13, and the convection heating surface channel 14. It exchanges heat with the superheater 15 in the convection heating surface channel 14 before being discharged from the boiler. A portion of the flue gas from the inlet of the second radiant channel 12 enters the cyclone separator 20 for separation. The separated high-temperature flue gas is discharged through the flue gas outlet, and the separated ash is discharged from the ash discharge port into the ash hopper 16.

[0025] This system has three working states:

[0026] In the first operating state, the first flue gas damper 22 is closed, the second flue gas damper 24 is closed, and the entire system is not operating.

[0027] In the second operating state, the first flue gas damper 22 is closed and the second flue gas damper 24 is open. The high-temperature flue gas discharged from the flue gas outlet of the cyclone separator 20 directly enters the flue gas outlet of the third radiant channel 13 through the second pipe 23. The flue gas does not flow through the second radiant channel 12 and the third radiant channel 13, which reduces the heat loss of this part of the flue gas in the second radiant channel 12 and the third radiant channel 13. This can increase the flue gas temperature entering the convective heating surface channel 14, and maximize the main steam temperature of the superheater 15 when the boiler is first started.

[0028] In the third working state, the first flue gas baffle 22 is open and the second flue gas baffle 24 is closed. The high-temperature flue gas discharged from the flue gas outlet of the cyclone separator 20 directly enters the flue gas inlet of the third radiation channel 13 through the first pipe 21. The flue gas does not flow through the second radiation channel 12 but still flows through the third radiation channel 13, which reduces the heat loss of this part of the flue gas in the second radiation channel 12. The reduced heat absorption is less than that in the first working state.

[0029] This system, on the one hand, increases the flue gas temperature entering the convective heating surface channel 14 by controlling the amount of flue gas entering the third radiant channel 13 to participate in boiler heat exchange. This causes the main steam temperature in the superheater 15 to rise rapidly and reach its rated parameters, thus improving operating efficiency. On the other hand, while increasing the amount of ash discharged from the boiler front end, it reduces the overall amount of fly ash in the boiler, thereby reducing investment in flue gas purification equipment at the boiler tail end and the amount of hazardous waste requiring treatment.

[0030] This embodiment is a horizontally arranged waste heat boiler 10, and the principle is the same for a vertically arranged waste heat boiler 10.

[0031] In one embodiment, the flue gas outlet of the cyclone separator 20 is also connected to the flue gas outlet of the second radiation channel 12 via a third pipe 25, on which a third flue gas baffle 26 is installed.

[0032] In one embodiment, the system further includes a shock wave cleaning assembly 30, which includes four shock wave cleaners 31 arranged at equal intervals along the circumference of the cyclone separator 20.

[0033] The main purpose is to prevent ash and slag inside the cyclone separator 20 from sticking to the inner wall and failing to fall off on their own in time. The shock wave cleaning component 30 can blow the inner wall of the cyclone separator 20 to facilitate the falling off of the attached ash and slag.

[0034] In one embodiment, the number of shock wave cleaning components 30 is 2-3, and the 2-3 shock wave cleaning components 30 are arranged at equal intervals along the height direction of the cyclone separator 20 to improve the cleaning effect.

[0035] In one embodiment, an expansion joint 40 is further included. The inlet of the expansion joint 40 is connected to the flue gas inlet of the second radiation channel 12, and the outlet of the expansion joint 40 is connected to the inlet of the cyclone separator 20. The expansion joint 40 is used to compensate for expansion and contraction caused by temperature changes.

[0036] In one embodiment, a butterfly valve is installed at the inlet of the cyclone separator 20, which can close or open the flow of high-temperature flue gas to the cyclone separator 20, thereby controlling the operation or shutdown of the entire system.

[0037] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. It will be apparent to those skilled in the art that this utility model is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or basic characteristics of this utility model. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of this utility model is defined by the appended claims rather than the foregoing description, and thus all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this utility model.

[0038] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A high-efficiency flue gas circulation bypass system for starting up a waste heat boiler, used in conjunction with a waste heat boiler and an ash hopper, wherein the waste heat boiler has a first radiant channel, a second radiant channel, and a third radiant channel, characterized in that: include: A cyclone separator is installed outside the waste heat boiler. The inlet of the cyclone separator is connected to the flue gas inlet of the second radiant channel, and the flue gas outlet of the cyclone separator is connected to the flue gas inlet of the third radiant channel through a first pipe. A first flue gas baffle is installed on the first pipe. The flue gas outlet of the cyclone separator is also connected to the flue gas outlet of the third radiant channel through a second pipe. A second flue gas baffle is installed on the second pipe. The ash discharge port of the cyclone separator is connected to the ash hopper.

2. The efficient waste heat boiler start-up flue gas circulation bypass system according to claim 1, characterized in that: The flue gas outlet of the cyclone separator is also connected to the flue gas outlet of the second radiation channel through a third pipe, and a third flue gas baffle is installed on the third pipe.

3. The efficient waste heat boiler start-up flue gas circulation bypass system according to claim 1, characterized in that: It also includes a shock wave cleaning assembly, which includes four shock wave cleaners, which are arranged at equal intervals along the circumference of the cyclone separator.

4. The efficient waste heat boiler start-up flue gas circulation bypass system according to claim 3, characterized in that: The number of shock wave cleaning components is 2-3, and the 2-3 shock wave cleaning components are arranged at equal intervals along the height direction of the cyclone separator.

5. A high-efficiency waste heat boiler start-up flue gas circulation bypass system according to claim 4, characterized in that: It also includes an expansion joint, the inlet of which is connected to the flue gas inlet of the second radiation channel, and the outlet of which is connected to the inlet of the cyclone separator.

6. The efficient waste heat boiler start-up flue gas circulation bypass system according to claim 1, characterized in that: A butterfly valve is installed at the inlet of the cyclone separator.

Images