Flue gas temperature measurement structure for fluidized bed boiler

Abstract

The utility model relates to a flue gas temperature measurement structure of a fluidized bed boiler, including a water-cooled air chamber, an ignition tube is installed at the rear side of the water-cooled air chamber, and a thermocouple is installed on the ignition tube through a sleeve assembly; the sleeve assembly includes an outer sleeve, a temperature measuring hole is radially opened in the main air duct, the outer sleeve is installed in the temperature measuring hole, an inner sleeve is installed on the inner circumference of the outer sleeve through a flange structure, a thermocouple is installed in the inner sleeve, and the thermocouple and the bottom of the inner sleeve extend into the ignition tube. The ignition tube is composed of a main air duct, a mixed air duct and a combustion chamber connected in sequence, the mixed air duct is an annular pipe structure, the inner circumference of the mixed air duct is connected with the main air duct and the combustion chamber, an air inlet is installed on the outer wall of the mixed air duct, and a plurality of air outlets are evenly distributed on the inner wall of the mixed air duct. After the cold air enters the mixed air duct from the air inlet, it is divided into several strands and then flows into the main air duct from the air outlet. The utility model is easy to install and maintain, safe and reliable, can effectively protect the temperature measuring element, reduce the number of damages of the temperature measuring element, and is conducive to reducing the operating cost of the boiler user unit.

Description

Technical Field

[0001] The utility model belongs to the technical field of boilers and relates to a flue gas temperature measuring structure of a fluidized bed boiler. Background Art

[0002] Temperature is an important parameter in the operation of fluidized bed boilers. Its measurement and control are important means to ensure the safe operation of fluidized bed boilers, especially the control of flue gas temperature in the ignition tube of fluidized bed boilers, which directly affects the safety of the ignition stage of fluidized bed boilers.

[0003] When the fluidized bed boiler uses an ignition oil gun under the bed to ignite the furnace, the temperature rise rate must be controlled within 30℃ / h. After the temperature rises to 150℃ and the temperature is kept constant for 20 hours, the flue gas temperature is increased at a rate of 30℃ / h. When the temperature rises to 300℃, the temperature is kept constant for 24 hours. If the flue gas temperature in the ignition barrel increases too quickly during the furnace drying stage, the moisture in the furnace wall will quickly evaporate due to the heat, causing the volume to expand and generate a certain pressure, causing the furnace wall to crack, deform, and be damaged. In severe cases, the furnace wall will fall off. During the ignition stage before the normal operation of the boiler, the temperature change in the ignition tube must be controlled within 100℃ / h. If the temperature rises and falls too quickly, the furnace wall in the ignition tube is also prone to deformation and damage. In summary, the measurement and control of the flue gas temperature in the fluidized bed ignition tube is particularly important. Summary of the invention

[0004] The utility model aims to provide a flue gas temperature measuring structure for a fluidized bed boiler, which can solve the above-mentioned problems and is beneficial to reducing the operating cost of the boiler user unit.

[0005] According to the technical solution provided by the utility model: a flue gas temperature measuring structure of a fluidized bed boiler includes a water-cooled air chamber, an ignition tube is installed on the rear side of the water-cooled air chamber, and a thermocouple is installed on the ignition tube through a sleeve assembly; the sleeve assembly includes an outer sleeve, a temperature measuring hole is radially opened in the main air duct, the outer sleeve is installed in the temperature measuring hole, an inner sleeve is installed on the inner circumference of the outer sleeve through a flange structure, a thermocouple is installed in the inner sleeve, and the thermocouple and the bottom of the inner sleeve extend into the ignition tube.

[0006] As a further improvement of the present utility model, the ignition tube is composed of a main air duct, a mixing air duct and a combustion chamber which are connected in sequence. The mixing air duct is an annular tube structure. The inner circumference of the mixing air duct is connected with the main air duct and the combustion chamber. An air inlet is installed on the outer wall of the mixing air duct, and several air outlets are evenly distributed on the inner wall of the mixing air duct. The cold air enters the mixing air duct from the air inlet and is divided into several streams and then flows into the main air duct from the air outlet.

[0007] As a further improvement of the utility model, the air outlet and the center of the air mixing duct are at an angle.

[0008] As a further improvement of the present invention, the angle between the air outlet and the center of the air mixing duct is 20°.

[0009] As a further improvement of the utility model, the outer sleeve is installed in the temperature measuring hole through a welding process.

[0010] As a further improvement of the utility model, an outer sleeve flange is installed on the upper part of the outer sleeve by welding technology, an inner sleeve lower flange is provided on the outer periphery of the middle part of the inner sleeve, and the inner sleeve lower flange is connected to the outer sleeve flange by bolts; the outer sleeve flange is located on the outer periphery of the main air duct.

[0011] As a further improvement of the utility model, the outer sleeve is in the form of an open lower end, and the inner sleeve is in the form of a blind tube.

[0012] As a further improvement of the utility model, a sealing gasket is installed between the lower flange of the inner sleeve and the flange of the outer sleeve.

[0013] As a further improvement of the utility model, the thermocouple is installed in the inner sleeve through a flange structure; the thermocouple is provided with a thermocouple flange, an inner sleeve upper flange is provided on the outer periphery of the upper part of the inner sleeve, and the inner sleeve upper flange is connected to the thermocouple flange through bolts.

[0014] As a further improvement of the utility model, the outer sleeve material is made of heat-resistant stainless steel 06Cr18Ni11Ti, and the inner sleeve material is made of high-temperature resistant alloy GH30.

[0015] The positive effects of this application are:

[0016] The utility model is convenient to install and maintain, safe and reliable, can effectively protect the temperature measuring element, reduces the damage times of the temperature measuring element, and is beneficial to reducing the operation cost of the boiler user unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the utility model.

[0018] Figure 2 The utility model is a schematic diagram of the structure of the thermocouple installed in the casing assembly.

[0019] Figure 3 It is a structural schematic diagram of the ignition tube of the utility model.

[0020] Figure 4 for Figure 3 Schematic diagram of direction A in .

[0021] Figure 1-Figure 4 The invention comprises an outer sleeve 1.1, an inner sleeve 1.2, an outer sleeve flange 1.3, an ignition tube 4, a main air duct 4.1, an air mixing duct 4.2, a combustion chamber 4.3, a thermocouple 5, and a water-cooled air chamber 6. DETAILED DESCRIPTION

[0022] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0023] In order to enable those skilled in the art to better understand the solution of the utility model, the following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0024] It should be noted that the terms "first", "second", etc. in the specification and claims of the utility model and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so as to describe the embodiments of the utility model described herein. In addition, similar terms such as "including" and "having" mean that in addition to those contents already listed in "including" and "having", other contents that have not been listed can also be "included" and "having"; for example, a process, method, system, product or device that can include a series of steps or units is not necessarily limited to those steps or units that have been clearly listed, but can include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0025] Due to the angle of the drawing, some components may not be drawn, but their positions and connection relationships can be partially understood based on the text expression.

[0026] like Figure 1 As shown, the utility model is a flue gas temperature measuring structure of a fluidized bed boiler, comprising a water-cooled air chamber 6, an ignition tube 4 is installed at the rear side of the water-cooled air chamber 6, and a thermocouple 5 is installed on the ignition tube 4 through a sleeve assembly.

[0027] like Figure 3 As shown, the ignition tube 4 is composed of a main air duct 4.1, a mixed air duct 4.2 and a combustion chamber 4.3 which are connected in sequence, and the smoke flows along the combustion chamber 4.3, the mixed air duct 4.2 and the main air duct 4.1 to the water-cooled air chamber 6. The mixed air duct 4.2 is an annular pipe structure, and the inner periphery of the mixed air duct 4.2 is connected with the main air duct 4.1 and the combustion chamber 4.3. An air inlet 4.21 is installed on the outer wall of the mixed air duct 4.2, and a plurality of air outlets 4.22 are evenly distributed on the inner wall of the mixed air duct 4.2. After the cold air enters the mixed air duct 4.2 from the air inlet 4.21, it is divided into several streams and then flows into the main air duct 4.1 from the air outlet 4.22, as shown in FIG. Figure 4 shown.

[0028] The air outlet 4.22 and the center of the air mixing channel 4.2 are angled so that the cold air blown into the ignition tube 4 has a swirl flow, which is better mixed with the smoke and increases the smoke temperature of the water-cooled air chamber during ignition. In this embodiment, the angle between the air outlet 4.22 and the center of the air mixing channel 4.2 is 20°.

[0029] The sleeve assembly includes an outer sleeve 1.1, a main air duct 4.1 radially has a temperature measuring hole, the outer sleeve 1.1 is installed in the temperature measuring hole by welding process, the inner sleeve 1.2 is installed on the inner periphery of the outer sleeve 1.1 through a flange structure, a thermocouple 5 is installed in the inner sleeve 1.2, and the thermocouple 5 and the bottom of the inner sleeve 1.2 extend into the ignition tube 4.

[0030] like Figure 2 As shown, specifically, an outer sleeve flange 1.3 is installed on the upper part of the outer sleeve 1.1 by welding, an inner sleeve lower flange 1.5 is provided on the outer periphery of the middle part of the inner sleeve 1.2, and the inner sleeve lower flange 1.5 is connected to the outer sleeve flange 1.3 by bolts. The outer sleeve flange 1.3 is located on the outer periphery of the main air duct 4.1.

[0031] The outer sleeve 1.1 is open at the lower end, and the inner sleeve 1.2 is a blind tube. The outer sleeve 1.1 separates the thermocouple 5 from the ignition barrel 4 to prevent the barrel wall of the ignition barrel 4 from overheating and deforming. The function of the inner sleeve 1.2 is to prevent the smoke in the ignition barrel 4 from overflowing.

[0032] In order to prevent smoke in the main air duct 4.1 from being discharged from between the inner sleeve lower flange 1.5 and the outer sleeve flange 1.3, a sealing gasket is installed between the inner sleeve lower flange 1.5 and the outer sleeve flange 1.3.

[0033] The thermocouple 5 is installed in the inner sleeve 1.2 through a flange structure. The thermocouple 5 is provided with a thermocouple flange 5.1. An inner sleeve upper flange 1.4 is provided on the outer periphery of the upper part of the inner sleeve 1.2. The inner sleeve upper flange 1.4 is connected to the thermocouple flange 5.1 through bolts.

[0034] The bolts, nuts, etc. used to connect the flanges are all high-strength connectors; the outer sleeve 1.1 is made of heat-resistant stainless steel 06Cr18Ni11Ti, and the inner sleeve 1.2 is made of high-temperature resistant alloy GH30.

[0035] The working process of the utility model is as follows:

[0036] The ignition tube 4 is installed on the water-cooled air chamber 6, and the thermocouple 5 measures the temperature of the gas about to enter the water-cooled air chamber 6. When the thermocouple 5 is damaged or repaired, it is not necessary to stop the furnace, and the thermocouple flange 5.1 can be directly removed for replacement, which saves time and labor and greatly reduces the operation and maintenance costs.

[0037] It is understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A flue gas temperature measurement structure for a fluidized bed boiler, comprising a water-cooled air chamber (6), an ignition tube (4) being installed at the rear side of the water-cooled air chamber (6), characterized in that: A thermocouple (5) is installed on the ignition tube (4) through a sleeve assembly; the sleeve assembly comprises an outer sleeve (1.1); a temperature measuring hole is radially opened in the main air duct (4.1); the outer sleeve (1.1) is installed in the temperature measuring hole; an inner sleeve (1.2) is installed on the inner circumference of the outer sleeve (1.1) through a flange structure; a thermocouple (5) is installed in the inner sleeve (1.2); and the thermocouple (5) and the bottom of the inner sleeve (1.2) extend into the ignition tube (4).

2. The flue gas temperature measurement structure of a fluidized bed boiler according to claim 1, characterized in that: The ignition tube (4) is composed of a main air duct (4.1), a mixed air duct (4.2) and a combustion chamber (4.3) which are connected in sequence. The mixed air duct (4.2) is an annular tube structure. The inner periphery of the mixed air duct (4.2) is connected to the main air duct (4.1) and the combustion chamber (4.3). An air inlet (4.21) is installed on the outer wall of the mixed air duct (4.2). A plurality of air outlets (4.22) are evenly distributed on the inner wall of the mixed air duct (4.2). Cold air enters the mixed air duct (4.2) from the air inlet (4.21) and is divided into several streams before flowing into the main air duct (4.1) from the air outlet (4.22).

3. The flue gas temperature measurement structure of a fluidized bed boiler according to claim 2, characterized in that: The air outlet (4.22) and the center of the air mixing duct (4.2) are at an angle.

4. The flue gas temperature measurement structure of a fluidized bed boiler according to claim 3, characterized in that: The included angle between the air outlet (4.22) and the center of the air mixing duct (4.2) is 20°.

5. The flue gas temperature measurement structure of a fluidized bed boiler according to claim 1, characterized in that: The outer sleeve (1.1) is installed in the temperature measuring hole by welding.

6. The flue gas temperature measurement structure of a fluidized bed boiler according to claim 1, characterized in that: An outer sleeve flange (1.3) is installed on the upper part of the outer sleeve (1.1) by welding, an inner sleeve lower flange (1.5) is provided on the outer periphery of the middle part of the inner sleeve (1.2), and the inner sleeve lower flange (1.5) is connected to the outer sleeve flange (1.3) by bolts; the outer sleeve flange (1.3) is located on the outer periphery of the main air duct (4.1).

7. The flue gas temperature measurement structure of a fluidized bed boiler according to claim 1, characterized in that: The outer sleeve (1.1) is open at the lower end, and the inner sleeve (1.2) is a blind tube.

8. The flue gas temperature measurement structure of a fluidized bed boiler according to claim 6, characterized in that: A sealing gasket is installed between the lower flange (1.5) of the inner sleeve and the flange (1.3) of the outer sleeve.

9. The flue gas temperature measurement structure of a fluidized bed boiler according to claim 1, characterized in that: The thermocouple (5) is installed in the inner sleeve (1.2) via a flange structure; the thermocouple (5) is provided with a thermocouple flange (5.1); an inner sleeve upper flange (1.4) is provided on the outer periphery of the upper portion of the inner sleeve (1.2); and the inner sleeve upper flange (1.4) is connected to the thermocouple flange (5.1) via bolts.

10. The flue gas temperature measurement structure of a fluidized bed boiler according to claim 1, characterized in that: The outer sleeve (1.1) is made of heat-resistant stainless steel 06Cr18Ni11Ti, and the inner sleeve 1.2 is made of high-temperature resistant alloy GH30.

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