Flue gas desulfurization device based on calcium-based absorbent

Abstract

The flue gas desulfurization device based on the calcium-based absorbent, provided by the utility model, is high in desulfurization efficiency, simple in structure, simple to operate and maintain, and capable of efficiently absorbing sulfur oxides in flue gas so as to realize flue gas treatment. The bottom end of the desulfurizing tower shell is communicated with an inlet smoke box, the end part of the inlet smoke box is communicated with a smoke inlet, and an inlet smoke guide plate is arranged in the inlet smoke box close to the smoke inlet; the top end of the desulfurizing tower shell is communicated with an outlet smoke box, the end part of the outlet smoke box is communicated with a smoke outlet, and an outlet smoke guide plate is arranged in the outlet smoke box close to the smoke outlet; a rectifying grid is arranged in the desulfurizing tower shell close to the inlet smoke box; the first desulfurization module layer, the second desulfurization module layer,..., the nth desulfurization module layer are sequentially arranged in the desulfurization tower shell from bottom to top from the upper part of the rectification grid; each desulfurization module layer is provided with a plurality of calcium-based absorbent boxes; a plurality of loading and unloading doors in one-to-one correspondence with the desulfurization module layers are formed in the wall plate of the desulfurization tower shell.

Description

Technical Field

[0001] The utility model belongs to the technical field of flue gas treatment, in particular to the treatment of sulfur-containing flue gas, and specifically is a flue gas desulfurization device based on a calcium-based absorbent. Background Art

[0002] my country is a large coal producer and consumer. The main pollutants formed by coal combustion are dust, sulfur oxides, and nitrogen oxides. The environmental pollution problems caused by this are becoming increasingly serious and have attracted widespread attention from all walks of life. At present, relatively mature flue gas desulfurization technologies mainly include wet, dry and semi-dry methods. Wet technologies mainly include ammonia method, limestone-gypsum method, double alkali method, etc. The desulfurization efficiency of wet technology is generally high, which can reach about 95%, but there are problems such as serious equipment corrosion, high operation and maintenance costs, and easy secondary pollution. The sulfur removal efficiency of the semi-dry method can reach about 90%, but there are problems such as high operation and maintenance costs and easy secondary pollution. Dry technologies mainly include activated carbon method, calcium-based desulfurization method, and sodium-based desulfurization method. Among them, the flue gas desulfurization technology based on calcium-based absorbent has an efficiency of more than 95%. At the same time, the process flow is short, and water should not be used in the production process, so no wastewater and equipment corrosion problems are generated. It is one of the preferred technologies suitable for sulfur-containing flue gas treatment. Therefore, the research work on flue gas desulfurization technology based on calcium-based absorbent has important application value.

[0003] The desulfurization tower is the core equipment of the flue gas desulfurization system based on calcium-based absorbents. However, the existing desulfurization towers have many problems such as complex equipment structure, low utilization rate of calcium-based absorbents, and uneven airflow distribution in the desulfurization tower, which leads to unstable desulfurization efficiency and high equipment operation and maintenance costs. Therefore, the structure of the desulfurization tower needs to be further improved. For example:

[0004] Chinese patent CN211800016U discloses a moving bed dry desulfurization device using a calcium-based absorbent, which includes a raw flue gas inlet door, a waste discharge mechanism, and a clean flue gas outlet door. It is characterized in that the ash discharge valve can continuously discharge the calcium-based absorbent at the bottom, but there are problems such as low utilization of the calcium-based absorbent, no flue gas distribution device, and difficulty in operating and maintaining the moving equipment.

[0005] Chinese patent CN215693055U discloses a calcium-based moving bed fully dry desulfurization and dust removal system, which includes multiple dry towers and bypass flues. It is characterized in that the dry towers are arranged side by side, and the gate valve and the discharge valve under the tower can control the discharge amount. However, the construction cost of the device is high and the operation and maintenance are difficult. Utility Model Content

[0006] The utility model provides a flue gas desulfurization device based on a calcium-based absorbent, and aims to provide a flue gas desulfurization treatment device with high desulfurization efficiency, simple structure, uniform flue gas distribution, simple operation and maintenance, and suitable for the advantages of the calcium-based absorbent process in view of the above-mentioned deficiencies in the prior art.

[0007] The technical solution adopted by the utility model to solve its technical problems is:

[0008] A flue gas desulfurization device based on calcium-based absorbent comprises a desulfurization tower shell, wherein the bottom end of the desulfurization tower shell is connected to an inlet smoke box, the end of the inlet smoke box is connected to a smoke inlet, and an inlet smoke guide plate is arranged near the smoke inlet in the inlet smoke box; the top end of the desulfurization tower shell is connected to an outlet smoke box, the end of the outlet smoke box is connected to a smoke outlet, and an outlet smoke guide plate is arranged near the smoke outlet in the outlet smoke box; a rectifying grid is arranged near the inlet smoke box in the desulfurization tower shell; starting from above the rectifying grid, the first desulfurization module layer, the second desulfurization module layer ... the nth desulfurization module layer are arranged in sequence from bottom to top in the desulfurization tower shell; each desulfurization module layer is provided with a plurality of calcium-based absorbent boxes; a plurality of loading and unloading doors corresponding to each desulfurization module layer are provided on the wall panel of the desulfurization tower shell.

[0009] Furthermore, the calcium-based absorbent box is supported by a supporting structure and fixed in the desulfurization tower shell.

[0010] Furthermore, the inlet smoke guide plate and the outlet smoke guide plate are both composed of a plurality of steel plates arranged at a specific angle, where the angle refers to the angle between the smoke guide plate and the horizontal plane, and the angle ranges from 20° to 70°.

[0011] Furthermore, the bottom of the inlet cigarette box has an inclined surface inclined upward at a specific inclination angle, and the top of the outlet cigarette box has an inclined surface inclined downward at a specific inclination angle; the above-mentioned inclination angle refers to the angle between the inclined surface at the bottom of the inlet cigarette box or the inclined surface at the top of the outlet cigarette box and the horizontal plane, and the inclination angle range is 20° to 70°.

[0012] Furthermore, the rectifying grid is one of a louver plate, a microporous plate, and a Johnson mesh.

[0013] Furthermore, the calcium-based absorbent box and the supporting structure are detachably mounted.

[0014] Furthermore, the main components of the calcium-based absorbent are slaked lime and a binder.

[0015] The beneficial effects of the utility model include:

[0016] 1) The utility model provides an inlet smoke guide plate in the inlet smoke box and an outlet smoke guide plate in the outlet smoke box, which is beneficial to improving the flow uniformity of the smoke, ensuring uniform distribution of the smoke, and solving the problem of reduced desulfurization efficiency due to uneven distribution of the smoke;

[0017] 2) The bottom of the inlet smoke box of the utility model has an inclined surface inclined upward at a specific angle, and the top of the outlet smoke box has an inclined surface inclined downward at a specific angle, which can realize the diversion of inlet and outlet smoke and reduce the pressure loss of smoke;

[0018] 3) The number of desulfurization module layers of the utility model can be adjusted and optimized according to the parameters such as the amount of flue gas to be treated, the content of flue gas pollutants, and the process characteristics of the calcium-based absorbent, so as to ensure the desulfurization efficiency while reducing the construction cost;

[0019] 4) The number of calcium-based absorbent boxes on each layer of the utility model can be optimized according to the parameters such as the amount of flue gas to be treated, the content of flue gas pollutants, and the process characteristics of the calcium-based absorbent. At the same time, the arrangement can be adjusted according to the size of the space where the device is arranged to improve the adaptability of the device;

[0020] 5) The calcium-based absorbent box and the supporting structure of the utility model can be detachably installed, so that the calcium-based absorbent can be replaced, that is, the inactivated calcium-based absorbent box is transported out through the loading and unloading door, and the inactivated calcium-based desulfurizer is discharged and then filled with fresh calcium-based desulfurizer, and then transported into the desulfurization tower through the loading and unloading door, thereby reducing the operating cost;

[0021] 6) The utility model has no power equipment, no equipment and parts that need regular maintenance, no equipment wear problem, has high reliability, and can meet the requirements of long-term operation;

[0022] 7) The calcium-based absorbent of the utility model is filled in the calcium-based absorbent box, and the flue gas contacts the calcium-based absorbent in countercurrent, which does not cause wear and damage to the calcium-based absorbent, and is conducive to improving the absorption efficiency and service life of the calcium-based absorbent;

[0023] 8) The utility model has good adaptability to smoke load, and changes in smoke volume will not affect the operation of the device, and it can work normally within the load range of 0-100%;

[0024] In summary, the utility model provides a flue gas desulfurization device based on a calcium-based absorbent, which has the characteristics of high desulfurization efficiency, simple structure, and simple operation and maintenance. It can efficiently absorb sulfur oxides in the flue gas, thereby achieving the purpose of flue gas treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the overall structure of a flue gas desulfurization device based on a calcium-based absorbent of the utility model.

[0026] In the figure: 1- flue gas inlet, 2- inlet flue gas guide plate, 3- inlet smoke box, 4- rectifier grid, 5- desulfurization tower shell, 6- first desulfurization module layer, 61- support structure, 62- calcium-based absorbent box, 7- second desulfurization module layer, 8- nth desulfurization module layer, 9- loading and unloading door, 10- outlet smoke box, 11- outlet flue gas guide plate, 12- flue gas outlet. DETAILED DESCRIPTION

[0027] The technical solution of the utility model will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are 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 are within the scope of protection of the utility model.

[0028] In the description of the present invention, it should be noted that the terms "first", "second" and "nth" are only used to distinguish components and cannot be understood as indicating or implying relative importance. In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0029] Example 1

[0030] A flue gas desulfurization device based on a calcium-based absorbent, such as Figure 1 As shown: it includes a desulfurization tower shell 5, the lower port and the upper port of the desulfurization tower shell 5 are respectively connected to the inlet smoke box 3 and the outlet smoke box 10, the inlet smoke box 3 is connected to the flue gas inlet 1, the outlet smoke box 10 is connected to the flue gas outlet 12, the inlet flue gas guide plate 2 is arranged in the inlet smoke box 3 and close to the flue gas inlet 1, the outlet flue gas guide plate 11 is arranged in the outlet smoke box 10 and close to the flue gas outlet 12, the rectifier grid 4 is arranged in the desulfurization tower shell 5 and close to the inlet smoke box 3, the first desulfurization module layer 6, the second desulfurization module layer 7...the nth desulfurization module layer 8 are arranged in the desulfurization tower shell 5 from bottom to top, and the number of desulfurization module layers n is optimized according to parameters such as the amount of flue gas treated, the content of flue gas pollutants, and the process characteristics of the calcium-based absorbent. Each desulfurization module layer is composed of a support structure 61 and a plurality of calcium-based absorbent boxes 62. The calcium-based absorbent boxes 62 are supported and fixed by the support structure 61. The loading and unloading doors 9 are opened on the wall panels of the desulfurization tower shell 5. The number of loading and unloading doors 9 corresponds to the number of desulfurization module layers.

[0031] The inlet and outlet flue gas guide plates are composed of a series of steel plates arranged at a specific angle, and the angle (the angle between the flue gas guide plate and the horizontal plane) ranges from 20 to 70 degrees. The steel plates are fixed on the connecting rods to achieve uniform flow of flue gas, and the number, arrangement angle, and width of the inlet and outlet flue gas guide plates are optimized according to the parameters such as the amount of flue gas to be treated, the content of flue gas pollutants, and the flow field distribution in the desulfurization tower.

[0032] The lower (upper) plate of the inlet (outlet) smoke box has a specific inclination angle to achieve uniform distribution of inlet (outlet) flue gas and reduce flue gas pressure loss. The angle (the angle between the lower (upper) plate of the inlet (outlet) smoke box and the horizontal plane) ranges from 20 to 70° and is optimized based on parameters such as the amount of flue gas processed, the content of flue gas pollutants, and the flow field distribution in the desulfurization tower.

[0033] The rectifier grid can be a louver plate, a microporous plate or a Johnson mesh. Its function is to adjust the horizontal flow of the flue gas before entering the rectifier grid to a vertical flow through the collision and integration of the flue gas in the rectifier grid, and secondly, to integrate the flue gas velocity distribution to be relatively uniform.

[0034] The calcium-based absorbent box is a detachable structure, and is filled with calcium-based absorbent. After disassembly, the calcium-based absorbent can be replaced and used, and can be transported in and out of the desulfurization tower through the loading and unloading door. The main components of the calcium-based absorbent are slaked lime and adhesive.

[0035] When the device is in operation, the original flue gas enters the inlet smoke box 3 from the flue gas inlet 1, and enters the desulfurization tower evenly under the guidance of the inlet flue gas guide plate 2, and passes through the first desulfurization module layer 6, the second desulfurization module layer 7...the nth desulfurization module layer 8 in turn, and contacts with the calcium-based desulfurizer arranged in each layer, and SO in the original flue gas is desulfurized. 2 The pollutants react with the calcium-based absorbent and are absorbed, and the purified clean flue gas is discharged from the flue gas outlet 12 under the guidance of the outlet flue gas guide plate 11 arranged in the outlet smoke box 10.

[0036] There are certain differences in the deactivation speed of calcium-based absorbents in different desulfurization module layers. The calcium-based absorbent in the first desulfurization module layer first contacts the original flue gas, and its deactivation speed is the fastest; the nth desulfurization module layer contacts the flue gas after the n-1th layer of purification, and its deactivation speed is the slowest. According to the deactivation speed characteristics of different desulfurization modules, replacing the calcium-based absorbent in this layer can better improve the desulfurization efficiency and increase the comprehensive utilization rate of the calcium-based absorbent.

[0037] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A flue gas desulfurization device based on a calcium-based absorbent, characterized in that: The desulfurization tower shell (5) comprises a desulfurization tower shell (5), wherein the bottom end of the desulfurization tower shell (5) is connected to an inlet smoke box (3), the end of the inlet smoke box (3) is connected to a smoke inlet (1), and an inlet smoke guide plate (2) is arranged in the inlet smoke box (3) near the smoke inlet (1); the top end of the desulfurization tower shell (5) is connected to an outlet smoke box (10), the end of the outlet smoke box (10) is connected to a smoke outlet (12), and an outlet smoke guide plate (2) is arranged in the outlet smoke box (10) near the smoke outlet (12). 11); a rectifier grid (4) is arranged in a position near the inlet smoke box (3) in the desulfurization tower shell (5); starting from the top of the rectifier grid (4), the first desulfurization module layer (6), the second desulfurization module layer (7) ... the nth desulfurization module layer (8) are arranged in sequence from bottom to top in the desulfurization tower shell (5); each desulfurization module layer is provided with a plurality of calcium-based absorbent boxes (62); and a plurality of loading and unloading doors (9) corresponding to each desulfurization module layer are opened on the wall panel of the desulfurization tower shell (5).

2. A flue gas desulfurization device based on a calcium-based absorbent according to claim 1, characterized in that: The calcium-based absorbent box (62) is supported by a supporting structure (61) and fixed inside the desulfurization tower shell (5).

3. A flue gas desulfurization device based on a calcium-based absorbent according to claim 1, characterized in that: The inlet smoke guide plate (2) and the outlet smoke guide plate (11) are both composed of a plurality of steel plates arranged at a specific angle, where the angle refers to the angle between the smoke guide plate and the horizontal plane, and the angle range is 20° to 70°.

4. A flue gas desulfurization device based on a calcium-based absorbent according to claim 1 or 3, characterized in that: The bottom of the inlet smoke box (3) has an inclined surface inclined upward at a specific inclination angle, and the top of the outlet smoke box (10) has an inclined surface inclined downward at a specific inclination angle; the above-mentioned inclination angle refers to the angle between the bottom inclined surface of the inlet smoke box (3) or the top inclined surface of the outlet smoke box (10) and the horizontal plane, and the inclination angle ranges from 20° to 70°.

5. A flue gas desulfurization device based on a calcium-based absorbent according to claim 1, characterized in that: The rectifying grid (4) is one of a louver plate, a microporous plate, and a Johnson mesh.

6. A flue gas desulfurization device based on a calcium-based absorbent according to claim 2, characterized in that: The calcium-based absorbent box (62) and the supporting structure (61) are detachably mounted.

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