Heating surface anti-abrasion device based on air film wind dust removal
By installing a dust-expelling pipe at the inlet of the boiler's heating surface and using compressed air to form a film airflow, the problem of dust wear during boiler combustion is solved, achieving a low-cost and efficient anti-wear effect without affecting heat exchange performance.
Patent Information
- Application Number
- CN202423054270.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-11
- Publication Date
- 2025-12-30
- Estimated Expiration
- 2034-12-11
AI Technical Summary
In the boiler combustion process, coal ash causes severe wear on the heating surface. Existing methods are costly or affect heat exchange efficiency, and anti-wear measures pose a risk of wear.
Dust removal pipes are arranged at the inlet of the heated surface. Compressed air forms a film airflow, which creates a countercurrent jet to prevent dust from directly impacting the heated surface pipes. A combination structure of film airflow orifices and dust removal pipes is adopted.
It effectively reduces wear on the heating surface, maintains heat exchange efficiency, is suitable for retrofitting existing boilers, has low cost, and provides significant anti-wear effect.
Smart Images
Figure CN223740822U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to a boiler technical field, concretely relates to a device of heating surface anti-abrasion based on gas film wind dust removal. BACKGROUND
[0002] Coal is an important primary energy in our country, and most of the coal is used for boiler combustion power generation. Coal contains a certain amount of ash, so a large amount of dust is generated during combustion, and these dusts flow with flue gas, which causes erosion to the boiler heating surface, resulting in abrasion.
[0003] Because the coal resources in our country are very rich, but the coal quality is generally poor, the proportion of high water and high ash inferior coal is very high, and the abrasion effect on the boiler heating surface is more obvious. Researchers have proposed some methods to reduce the abrasion of the heating surface, for example, by adjusting the combustion mode, such as concentrated combustion and improving the configuration of primary, secondary and tertiary air, the furnace temperature can be improved, which is beneficial to the stable ignition and combustion of coal powder and reduces the dust content, but the effect is usually effective. Through material selection, surface treatment and other methods, the abrasion resistance of the heating surface can be improved, but the cost is relatively high, and the economy is poor. In addition, the anti-abrasion tile can be arranged at the inlet of the heating surface to reduce the abrasion of the heating surface, but the anti-abrasion tile will reduce the heat exchange coefficient of the heating surface, and can protect the first row of tube bundles. For the boiler with particularly serious abrasion, 1-3 rows of false pipes are arranged at the inlet of the heating surface, however, these false pipes also have the risk of abrasion. CONTENT
[0004] In order to make up for the shortcomings of the prior art, the utility model provides a device of heating surface anti-abrasion based on gas film wind dust removal.
[0005] The technical scheme of the utility model is as follows:
[0006] A device of heating surface anti-abrasion based on gas film wind dust removal, including flue, heating surface and heating surface pipe, a row of dust removal pipes is arranged at the inlet of the heating surface, and the dust removal pipe is located in front of the heating surface pipe along the flue gas flow direction, a row of gas film wind small holes is arranged on the dust removal pipe; compressed air is introduced into the dust removal pipe, and a jet flow is generated at the gas film wind small hole, the jet flow is turned back under the action of flue gas, and a gas film wind is formed on both sides of the dust removal pipe.
[0007] Further, the gas film wind small holes are arranged on the windward surface of the dust removal pipe.
[0008] Further, the inner diameter of the gas film wind small hole is 2-4mm, and the spacing between adjacent gas film wind small holes is 20-40mm.
[0009] Further, the pressure of the compressed air introduced into the dust removal pipe is 0.4-0.8MPa.
[0010] Further, the heated surface tube is arranged in a row.
[0011] Further, the diameter, number and arrangement of the dust removal tube are consistent with the single-row heated surface tube, that is, the dust removal tube is arranged in front of the heated surface tube.
[0012] The utility model has the advantages that:
[0013] 1) The device sets a row of dust removal tubes at the inlet of the heated surface, uses compressed air to form a small jet flow in the countercurrent direction, forms an air film on both sides of the dust removal tube, makes the dust bypass the heated surface, avoids the direct impact of the dust on the tube, and the method is unique and the effect is remarkable.
[0014] 2) The device does not increase the system resistance, and the amount of compressed air used is very small, which does not affect the heat exchange of the heated surface.
[0015] 3) The device is convenient to implement, and is particularly suitable for the transformation of existing boilers. BRIEF DESCRIPTION OF DRAWINGS
[0016] Figure 1 It is the dust removal tube arrangement drawing of the utility model; Figure 1 In the figure, 1 is a dust removal tube; and 2 is a heated surface.
[0017] Figure 2 It is a structural schematic view of the dust removal tube; Figure 2 In the figure, 1-1 is an air film wind small hole; and 1-2 is a compressed air inlet.
[0018] Figure 3 It is a flow velocity distribution diagram around the dust removal tube; Figure 3 In the figure, (a) is that there is no air flow in the small hole, which is equivalent to an ordinary dummy tube; and (b) is that there is air flow in the small hole, which is equivalent to the state when the utility model works.
[0019] Figure 4 It is a flow line distribution diagram around the dust removal tube; Figure 4 In the figure, (a) is that there is no air flow in the small hole, which is equivalent to an ordinary dummy tube; and (b) is that there is air flow in the small hole, which is equivalent to the state when the utility model works.
[0020] Figure 5 It is a dust particle trajectory distribution around the dust removal tube; Figure 5 In the figure, (a) is that there is no air flow in the small hole, which is equivalent to an ordinary dummy tube; and (b) is that there is air flow in the small hole, which is equivalent to the state when the utility model works. DETAILED DESCRIPTION
[0021] The utility model will be further described in detail in combination with the drawings and examples, and it should be pointed out that the following examples are intended to facilitate the understanding of the utility model and do not have any limiting effect on the utility model.
[0022] As Figure 1 shown, a device for preventing abrasion of a heated surface based on air film wind dust driving is arranged with a row of dust driving pipes 1 at the inlet of the heated surface 2, a row of dense air film wind small holes 1-1 are arranged on the dust driving pipe 1, and the pipes of the heated surface 2 are arranged in a row.
[0023] As Figure 2 shown, the air film wind small holes 1-1 are arranged on the windward surface of the dust driving pipe 1, the inner diameter is 2-4mm, and the spacing between adjacent holes is 20-40mm. One end of the dust driving pipe 1 is provided with a compressed air inlet 1-2, and compressed air is passed through the dust driving pipe, and the compressed air pressure is 0.4-0.8MPa.
[0024] The diameter, number and arrangement mode of the dust driving pipe are consistent with the subsequent heated surface pipes.
[0025] The principle and working method of the utility model are as follows:
[0026] The compressed air is passed into the dust driving pipe 1 from the compressed air inlet 1-2, high-speed small jets are generated at the air film wind small holes 1-1, and are turned back under the action of flue gas, so that the air film wind is formed on both sides of the dust driving pipe. The air film wind can drive the dust particles away from the pipe, so that the dust particles pass through the gap between the pipes, and the pipe cannot be washed, thereby protecting the dust driving pipe at the inlet and the downstream heated surface pipe.
[0027] During operation, the dust driving effect can be adjusted according to the actual coal quality, when low-ash coal is used, the abrasion is not serious, the compressed air can be adjusted to be low or closed, at this time the dust driving pipe is equivalent to a common false pipe. When high-ash coal is used, it has strong abrasion, at this time the compressed air pressure can be increased to form a strong air film wind, and a significant dust driving effect is generated to reduce the abrasion of the heated surface.
[0028] Figures 3-5 It is a numerical simulation result, and the simulation conditions are that the flue gas temperature is 600 degrees, the flue gas flow rate is 5.5m / s, the dust driving pipe diameter is 40mm, and the small hole diameter is 2.5mm.
[0029] Figure 3 And Figure 4 are the flow rate and streamline distribution around the dust driving pipe. In the figure, (a) - no air flow in the small hole, equivalent to a common false pipe; (b) - air flow in the small hole, equivalent to the state when the utility model works. It can be seen that when there is air flow in the small hole, the air film wind can be formed on both sides of the dust driving pipe, and the air film wind can drive the dust away from the pipe to avoid direct washing of the pipe.
[0030] Figure 5Is the trajectory distribution of dust particles around the dust removal pipe. In the figure, (a) - no air flow in the small hole, equivalent to the ordinary false pipe; (b) - there is air flow in the small hole, equivalent to the working state of the utility model. It can be seen that when there is air flow in the small hole, the dust particles cannot directly hit the surface of the pipe, but go around, thereby greatly reducing the wear.
Claims
1. A device for preventing wear on a heated surface based on film dust removal, comprising a flue, a heated surface, and heated surface tubes, characterized in that: A row of dust removal pipes is arranged at the inlet of the heating surface, and the dust removal pipes are located in front of the heating surface pipes along the flow direction of the flue gas, and a row of air film wind small holes are arranged on the dust removal pipes; compressed air is introduced into the dust removal pipes to generate a jet at the air film wind small holes, the jet is turned back under the action of the flue gas, and an air film wind is formed on both sides of the dust removal pipe.
2. The device for preventing abrasion of the heated surface based on air film wind-driven dust removal according to claim 1, characterized in that: The air film wind small holes are arranged on the windward surface of the dust removal pipe.
3. The device for preventing abrasion of the heated surface based on air film wind-driven dust removal according to claim 1, characterized in that: The inner diameter of the air film wind small holes is 2-4 mm, and the spacing between adjacent air film wind small holes is 20-40 mm.
4. The device for preventing abrasion of the heated surface based on air film wind-driven dust removal according to claim 1, characterized in that: The pressure of the compressed air introduced into the dust removal pipe is 0.4-0.8 MPa.
5. The device for preventing abrasion of the heated surface based on air film wind-driven dust removal according to claim 1, characterized in that: The heating surface pipes are arranged in a row.
6. The device for preventing abrasion of the heated surface based on air film wind-driven dust removal according to claim 1, characterized in that: The diameter, number and arrangement mode of the dust removal pipes are consistent with the single-row heating surface pipes.