Boss structure and air distribution plate

Abstract

The utility model relates to the technical field of circulating fluidized beds, and discloses a boss structure and an air distribution plate, the boss structure comprises a lower boss and an upper boss arranged at the top of the lower boss, one end of the bottom of the upper boss in the width direction and one end of the top of the lower boss in the width direction are on the same vertical line, and the other end of the upper boss in the width direction and the other end of the top of the lower boss in the width direction are on the same vertical line. The width of the bottom of the upper boss is smaller than that of the top of the lower boss. According to the utility model, the problems of low-temperature coking and the like caused by the formation of a fluidization dead zone due to poor fluidization quality at the periphery of the air distribution plate when the boiler is in medium and low load in the prior art are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of circulating fluidized beds, in particular to a boss structure and an air distribution plate. Background Art

[0002] Thermal power generating units need to have excellent deep peak-shaving capabilities to absorb new energy indicators and help build a new power system with new energy as the main body.

[0003] Based on this, thermal power units will transform from power supply of electric quantity to power supply of regulation. This requires coal-fired units to adapt to the new situation - to absorb new energy and ensure the stability and security of power grid supply through deep peak regulation and flexible operation. In areas where new energy development is prominent, the demand for deep peak regulation of thermal power units is more urgent, requiring existing units to be able to operate with deep peak regulation through transformation. This requires boilers to take corresponding measures to ensure the safety and reliability of deep peak regulation operation of units.

[0004] As an advanced coal-fired technology, circulating fluidized bed combustion technology has the advantages of good fuel adaptability, high efficiency and low pollution emissions. It is widely used in power station boilers and industrial boilers. The air distribution plate is one of the key components in the circulating fluidized bed boiler combustion equipment. Its performance directly affects the fluidization condition of the fluidized bed boiler and the flow, combustion and heat transfer process in the combustion chamber, thereby affecting the performance of the fluidized bed boiler.

[0005] When the circulating fluidized bed boiler is running, solid particles will flow back down along the water-cooled wall. The direct impact of solid particles will easily cause the wind caps installed around the air distribution plate to wear. Therefore, when designing the circulating fluidized bed boiler, in order to prevent the wind caps installed around the air distribution plate from wearing, a boss made of refractory and wear-resistant materials is built around the air distribution plate. The boss is generally 200-600mm high and 400-600mm wide.

[0006] This kind of boss design can play a good role in protecting the wind cap when the circulating fluidized bed boiler is running at high load, due to the large circulating material and fluidizing air volume. However, when the unit needs to deeply adjust the peak load to medium and low load or even below 30% load, this kind of air distribution plate boss design will easily cause the following problems:

[0007] 1) When the load is low, the overall fluidization air volume of the air distribution plate is small. Due to the wide boss, the fluidization quality of the boss area will be poor or even non-fluidized, which will lead to a very high risk of low-temperature coking;

[0008] 2) Due to the wide boss and poor fluidization, the circulating material will accumulate on the boss, resulting in poor representativeness of the bed temperature measurement and failure to truly reflect the furnace temperature. When the boiler is adjusted to a low load, the boiler itself faces the problem of stable combustion, which will bring great difficulties to the operator in controlling the bed temperature and easily cause the boiler to flame out. Utility Model Content

[0009] In order to overcome the deficiencies of the prior art, the utility model provides a boss structure and an air distribution plate to solve the problems existing in the prior art such as poor fluidization quality around the air distribution plate of the boiler at medium and low loads, thereby forming a fluidization dead zone and causing low-temperature coking.

[0010] The technical solution adopted by the utility model to solve the above problems is:

[0011] A boss structure comprises a lower boss and an upper boss arranged on the top of the lower boss, wherein one end of the bottom of the upper boss in the width direction and one end of the top of the lower boss in the width direction are on the same vertical line, and the width of the bottom of the upper boss is smaller than the width of the top of the lower boss.

[0012] As a preferred technical solution, the width of the bottom of the upper boss is greater than half the width of the top of the lower boss.

[0013] As a preferred technical solution, the cross-sectional shape of the upper boss in the height direction is one of the following: a triangle, a trapezoid, a parallelogram, or a parallelogram with a notch at the top.

[0014] As a preferred technical solution, the angle between the plane where the top of the lower boss is located in the width direction and the side surface where the other end of the bottom of the upper boss is located in the width direction is ≥50°.

[0015] As a preferred technical solution, it also includes a lower bed temperature measuring point, which is located between the bottom and the top of the upper boss in the height direction.

[0016] As a preferred technical solution, it also includes an upper bed temperature measuring point arranged above the lower bed temperature measuring point, and the upper bed temperature measuring point is located between the bottom and the top of the upper boss in the height direction.

[0017] As a preferred technical solution, the lower boss is a castable structure.

[0018] As a preferred technical solution, the upper boss is a castable structure.

[0019] An air distribution plate comprises the above-mentioned boss structure and also comprises an air distribution plate water-cooling wall connected to the lower boss.

[0020] As a preferred technical solution, it also includes a wind hood connected to the air distribution plate water-cooled wall.

[0021] Compared with the prior art, the utility model has the following beneficial effects:

[0022] (1) The utility model solves the problem of poor fluidization quality around the air distribution plate at low and medium loads of the boiler, thereby forming a fluidization dead zone and causing low-temperature coking by changing the type of the air distribution plate boss. The fluidization quality around the air distribution plate at low and medium loads of the unit is improved. The upper surface of the lower boss still retains a certain width to offset the impact force of the wall-attached downflow, thereby protecting the wind cap installed around the air distribution plate and avoiding the formation of a fluidization dead zone and causing low-temperature coking.

[0023] (2) The utility model improves the representativeness of the bed temperature measurement points, avoiding the accident of the boiler shutting down during the deep peak regulation stage due to the poor representativeness of the bed temperature measurement and the failure to truly reflect the furnace temperature. It helps the operating personnel to adjust the bed temperature and realize safer, more stable and more reliable unit peak regulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of an air distribution plate in the prior art;

[0025] Figure 2 This is one of the structural schematic diagrams of the air distribution plate described in the utility model;

[0026] Figure 3 This is the second structural schematic diagram of the air distribution plate described in the utility model;

[0027] Figure 4 This is the third structural schematic diagram of the air distribution plate described in the utility model;

[0028] Figure 5 This is the fourth structural schematic diagram of the air distribution plate described in the utility model.

[0029] Marks and their corresponding names in the attached drawings: 1. lower boss, 2. wind cap, 3. castable in the air distribution plate area, 4. water-cooled wall of the air distribution plate, 5. lower bed temperature measuring point, 6. upper bed temperature measuring point, 7. upper boss, 8. water-cooled wall of the wind chamber. DETAILED DESCRIPTION

[0030] The present invention will be further described in detail below in conjunction with the embodiments and drawings, but the implementation manner of the present invention is not limited thereto.

[0031] Example 1

[0032] A boss structure includes a lower boss 1 and an upper boss 7 arranged on the top of the lower boss 1, one end of the bottom of the upper boss 7 in the width direction and one end of the top of the lower boss 1 in the width direction are on the same vertical line, and the width of the bottom of the upper boss 7 is smaller than the width of the top of the lower boss 1.

[0033] As a preferred technical solution, the width of the bottom of the upper boss 7 is greater than half the width of the top of the lower boss 1 .

[0034] As a preferred technical solution, the cross-sectional shape of the upper boss 7 in the height direction is one of the following: a triangle, a trapezoid, a parallelogram, or a parallelogram with a notch at the top.

[0035] As a preferred technical solution, the angle between the plane where the top of the lower boss 1 is located in the width direction and the side surface where the other end of the bottom of the upper boss 7 is located in the width direction is ≥50°.

[0036] As a preferred technical solution, it also includes a lower bed temperature measuring point 5, which is located between the bottom and the top of the upper boss 7 in the height direction.

[0037] As a preferred technical solution, it also includes an upper bed temperature measuring point 6 arranged above the lower bed temperature measuring point 5, and the upper bed temperature measuring point 6 is located between the bottom and the top of the upper boss 7 in the height direction.

[0038] As a preferred technical solution, the lower boss 1 is a castable structure.

[0039] As a preferred technical solution, the upper boss 7 is a castable structure.

[0040] An air distribution plate comprises the above-mentioned boss structure and also comprises an air distribution plate water-cooling wall 4 connected to the lower boss 1.

[0041] As a preferred technical solution, it also includes a hood 2 connected to the air distribution plate water-cooled wall 4.

[0042] Example 2

[0043] like Figures 1 to 5 As shown, as a further optimization of Example 1, based on Example 1, this embodiment also includes the following technical features:

[0044] The utility model solves the problem of poor fluidization quality around the air distribution plate of the boiler at medium and low loads, thereby forming a fluidization dead zone and causing low-temperature coking, by changing the type of the air distribution plate boss. The fluidization quality around the air distribution plate of the unit at medium and low loads is improved. The upper surface of the lower boss 1 still retains a certain width to offset the impact force of the downward flow against the wall, thereby protecting the wind hoods installed around the air distribution plate and avoiding the formation of a fluidization dead zone to cause low-temperature coking.

[0045] The utility model improves the representativeness of bed temperature measuring points, avoids the accident of boiler flameout in the deep peak regulation stage due to poor representativeness of bed temperature measurement and failure to truly reflect the furnace temperature, and helps operating personnel to adjust the bed temperature and realize safer, more stable and more reliable unit peak regulation.

[0046] The structure of a conventional circulating fluidized bed boiler air distribution plate includes a lower boss 1, an air cap 2, a casting material in the air distribution plate area 3, an air distribution plate water-cooled wall 4, a lower bed temperature measuring point 5, an upper bed temperature measuring point 6 and other components.

[0047] A wind distribution plate suitable for deep peak regulation of a circulating fluidized bed boiler comprises a lower boss 1 (preferably a castable type boss), a hood 2, a castable 3 in the wind distribution plate area, a water-cooled wall 4 of the wind distribution plate, a lower bed temperature measuring point 5 (preferably a probe structure), an upper bed temperature measuring point 6 (preferably a probe structure), and a newly added boss structure is an upper boss 7.

[0048] Figures 2 to 5 In the wind chamber, the water-cooled wall 8 is used for air intake.

[0049] The upper surface of the lower boss 1 still retains a certain width to offset the impact force of the downflow against the wall, thereby playing a role in protecting the hood close to the furnace wall.

[0050] like Figures 2 to 5 As shown, the newly added four upper bosses 7 can reduce the dead zone of fluidization at low loads in the boiler, prevent low-temperature coking, improve the representativeness of the bed temperature measurement points, and help the operating personnel to adjust the bed temperature.

[0051] Preferably, the upper bosses 7 are all castable structures.

[0052] Preferably, the bottom width of the upper boss 7 should be greater than half of the top width of the lower boss 1 .

[0053] The inclination angle a of the upper boss 7 should be ≥50°.

[0054] Compared with the prior art, the utility model has the following beneficial effects:

[0055] (2) The utility model solves the problem of poor fluidization quality around the air distribution plate at low and medium loads of the boiler, thereby forming a fluidization dead zone and causing low-temperature coking by changing the type of the air distribution plate boss. The fluidization quality around the air distribution plate at low and medium loads of the unit is improved. The upper surface of the lower boss still retains a certain width to offset the impact force of the wall-attached downflow, thereby protecting the wind cap installed around the air distribution plate and avoiding the formation of a fluidization dead zone and causing low-temperature coking.

[0056] (2) The utility model improves the representativeness of the bed temperature measurement points, avoiding the accident of the boiler shutting down during the deep peak regulation stage due to the poor representativeness of the bed temperature measurement and the failure to truly reflect the furnace temperature. It helps the operating personnel to adjust the bed temperature and realize safer, more stable and more reliable unit peak regulation.

[0057] As described above, the utility model can be implemented well.

[0058] The above is only a preferred embodiment of the utility model and does not limit the utility model in any form. According to the technical essence of the utility model, within the spirit and principles of the utility model, any simple modification, equivalent replacement and improvement made to the above embodiment still falls within the protection scope of the technical solution of the utility model.

Claims

1. A boss structure, It is characterized in that The invention comprises a lower boss (1) and an upper boss (7) arranged on the top of the lower boss (1), wherein one end of the bottom of the upper boss (7) in the width direction and one end of the top of the lower boss (1) in the width direction are on the same vertical line, and the width of the bottom of the upper boss (7) is smaller than the width of the top of the lower boss (1).

2. A boss structure according to claim 1, It is characterized in that The width of the bottom of the upper boss (7) is greater than half the width of the top of the lower boss (1).

3. A boss structure according to claim 1, It is characterized in that The cross-sectional shape of the upper boss (7) in the height direction is one of the following: a triangle, a trapezoid, a parallelogram, or a parallelogram with a notch at the top.

4. A boss structure according to claim 1, It is characterized in that The included angle between the plane on the width direction where the top of the lower boss (1) is located and the side surface on the width direction where the other end of the bottom of the upper boss (7) is located is ≥50°.

5. The boss structure according to claim 1, It is characterized in that It also includes a lower bed temperature measuring point (5), which is located between the bottom and the top of the upper boss (7) in the height direction.

6. A boss structure according to claim 5, It is characterized in that It also includes an upper bed temperature measuring point (6) arranged above the lower bed temperature measuring point (5), and the upper bed temperature measuring point (6) is located between the bottom and the top of the upper boss (7) in the height direction.

7. The boss structure according to claim 1, It is characterized in that The lower boss (1) is a castable structure.

8. A boss structure according to any one of claims 1 to 7, It is characterized in that The upper boss (7) is a castable structure.

9. A wind distribution plate, It is characterized in that It comprises a boss structure as claimed in any one of claims 1 to 8, and also comprises an air distribution plate water-cooled wall (4) connected to the lower boss (1).

10. The air distribution plate according to claim 9, It is characterized in that It also includes a wind cap (2) connected to the wind distribution plate water-cooled wall (4).

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