Nozzle and wet desulphurization process absorption tower system

Abstract

The invention discloses a nozzle and a wet desulphurization process absorption tower system, and belongs to the technical field of electrolytic aluminum equipment.The nozzle comprises a main body part and a liquid inlet part, two liquid inlets are formed in the main body part, and the nozzle with the double liquid inlets is specifically designed based on the desulphurization process of the electrolytic aluminum industry. Through the central symmetry design of the double liquid inlets and the cooperation of the channel structure on the nozzle, the flowing directions of slurry at the positions of the two liquid inlets can be opposite, so that the slurry collides after entering the cavity in the nozzle, the size and particle size of the slurry are reduced, and the desulfurization effect can be ensured under the condition of small circulating pump flow; therefore, the overall energy consumption of the wet desulphurization process is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of electrolytic aluminum equipment, and in particular relates to a nozzle and a wet desulfurization process absorption tower system. Background Art

[0002] The existing electrolytic aluminum industry is equipped with purification equipment. Most of the purification process projects adopt limestone-gypsum wet desulfurization process, that is, wet desulfurization process. The wet desulfurization process is mainly composed of flue gas system, slurry circulation system, gypsum discharge and dehydration system, limestone slurry preparation system, process water system, compressed air system and corresponding electronic control system. The system with the largest energy consumption is the slurry circulation system, which is also the most important system. It is mainly composed of absorption tower, slurry circulation pump, spray layer, nozzle, demister and absorption tower agitator. The standard of slurry circulation system refers to the design standard of ultra-low emission projects in thermal power industry, and eccentric hollow nozzle is selected. The surface area average particle size of slurry particles after nozzle atomization (that is, the ratio of the average surface area of ​​particles to the volume of particles is less than or equal to 1900um. Under the condition of magnetic particle size, the slurry circulation pump, an important equipment in the wet desulfurization process, is generally selected with a large flow rate. Therefore, the overall power consumption of wet desulfurization process is relatively high. Summary of the invention

[0003] The object of the present invention is to provide a nozzle to solve the problem of high energy consumption of the existing wet desulfurization process mentioned in the above background technology.

[0004] To achieve the above object, the present invention provides the following technical solution: a nozzle, comprising:

[0005] A main body portion, wherein a cylindrical cavity is defined in the main body portion and includes a top wall and a bottom wall spaced apart in the axial direction;

[0006] The liquid inlet portion is formed as a cylindrical body extending from the center of the top wall of the main body along the axial direction;

[0007] Two liquid inlets are formed on the top wall of the main body, the two liquid inlets are centrally symmetrically arranged about the center point of the top wall of the main body, and each of the liquid inlets has an outer edge extending along the lower edge of the liquid inlet portion and an inner edge spaced from the outer edge;

[0008] A liquid outlet is formed at the center of the bottom wall of the main body;

[0009] The channel structure comprises a side channel portion formed by vertically extending the inner edge and a top channel portion horizontally extending from the upper edge of the side channel portion and contacting the liquid inlet portion.

[0010] Preferably, the angle between the top channel portion and the horizontal plane is 8-10°.

[0011] Preferably, the liquid inlet has a first end and a second end, and the distance between the outer edge and the inner edge of the liquid inlet gradually decreases from the first end to the second end.

[0012] Preferably, at the first end position of the liquid inlet, the ratio between the distance between the outer edge and the inner edge of the liquid inlet and the diameter of the top wall of the main body is 1:25-1:30.

[0013] Preferably, the nozzle further comprises a liquid outlet portion, and the liquid outlet portion is formed by the edge of the liquid outlet extending in the axial direction away from the main body portion.

[0014] Preferably, the liquid outlet is a circular notch formed at the center of the main body.

[0015] Preferably, the liquid outlet portion includes a first section that contracts inwardly in the radial direction while extending away from the main body portion in the axial direction, and a second section that expands outwardly in the radial direction while extending away from the main body portion in the axial direction.

[0016] Preferably, the generatrix of the first section is an arc line.

[0017] On the other hand, the present application discloses a wet desulfurization process absorption tower system, comprising:

[0018] A tower body, in which a purification zone and a liquid storage zone are defined and arranged vertically, and the tower body is provided with an air inlet and an air outlet which are arranged vertically;

[0019] At least one cycle unit, a single cycle unit comprises:

[0020] A spray pipeline is arranged in the purification zone, and the spray pipeline is provided with a plurality of the above-mentioned nozzles arranged along the cross section of the purification zone;

[0021] A supply pipeline is provided with a pump, one end of the supply pipeline is connected to the spray pipeline, and the other end is communicated with the liquid storage area.

[0022] Preferably, a plurality of the circulation units are provided, and the spray pipelines in the plurality of the circulation units are arranged at intervals in the height direction of the tower body.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The present application specifically designs a nozzle with a double liquid inlet arrangement based on the desulfurization process of the electrolytic aluminum industry. Through the central symmetrical design of the double liquid inlets and the channel structure on the nozzle, the slurry flow directions at the two liquid inlets can be made opposite, so that the slurry collides after entering the cavity in the nozzle to achieve a reduction in the slurry particle size, and the desulfurization effect can be guaranteed at a small circulation pump flow rate, thereby reducing the overall energy consumption of the wet desulfurization process. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the absorption tower system structure;

[0026] Figure 2 This is the relationship between particle size and circulation pump flow rate;

[0027] Figure 3 This is the relationship between particle size and absorption tower resistance;

[0028] Figure 4 This is the relationship between particle size and comprehensive energy consumption;

[0029] Figure 5 It is a schematic diagram of the front cross section of the nozzle;

[0030] Figure 6 A schematic diagram of the nozzle cross section from top view.

[0031] In the figure:

[0032] 10. Nozzle;

[0033] 100, main body; 101, top wall; 102, bottom wall; 103, liquid inlet; 103a, outer edge; 103b, inner edge; 103c, first end; 103d, second end; 104, liquid outlet;

[0034] 200, channel structure; 201, side channel portion; 202, top channel portion;

[0035] 300, liquid inlet;

[0036] 400, liquid outlet; 400a, first section; 400b, second section;

[0037] 500, tower body; 501, purification section; 502, liquid storage section; 503, supply pipeline; 504, pump; 505, spray pipeline; 506, air inlet; 507, air outlet. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Reference Figure 1, is a schematic diagram of the structure of a wet flue gas desulfurization process absorption tower system (hereinafter referred to as the absorption tower system), the absorption tower system includes a tower body 500, the tower body 500 defines a purification zone 501 and a liquid storage zone 502, wherein the purification zone 501 is located above the liquid storage zone 502, and the tower body 500 is provided with an air outlet 507 and an air inlet 506 distributed up and down at the purification zone 501, and the flue gas flows into the purification zone 501 from the air inlet 506, and during the rising process, it contacts with the subsequent slurry and reacts with the slurry. The sulfur in the flue gas should be removed, and after purification, it will flow out from the top outlet 507. Further, the absorption tower system also includes at least one circulation unit, and a single circulation unit includes a supply pipeline 503 and a spray pipeline 505, wherein one end of the supply pipeline 503 is connected to the liquid storage interval 502, and the other end is connected to the inlet end of the spray pipeline 505, and a pump 504 (i.e., a circulation pump 504) is arranged on the supply pipeline 503. Under the action of the pump 504, the slurry stored in the liquid storage interval 502 is After flowing through the supply pipeline 503, it enters the spray pipeline 505. Correspondingly, the above-mentioned spray pipeline 505 is arranged along the cross-section of the purification interval 501, and a plurality of nozzles 10 are configured on the spray pipeline 505. The spray range of the plurality of nozzles 10 is based on covering the cross-section of the purification interval 501, that is, the plurality of nozzles 10 are configured along the cross-section of the purification interval 501. The nozzle 10 is configured to atomize the slurry so that the slurry is sprayed with a specific particle size (the ratio of the average surface area of ​​the particles to the volume of the particles, that is, the aforementioned atomization particle size) to increase the contact area between the slurry and the flue gas, thereby improving the removal effect of pollutants such as SO2. In some embodiments, when there are multiple circulation units, the spray pipelines 505 of the multiple circulation units are arranged at intervals in the vertical direction. At this time, the rising flue gas sequentially contacts the slurry (such as gypsum slurry) sprayed from nozzles at different position heights to improve the removal effect of pollutants such as SO2. By way of example, the above-mentioned circulation units are configured with three, at this time two of which are common circulation units and the other is a spare circulation unit.

[0040] Based on the above absorption tower system, a power consumption test was conducted. Under similar flue gas conditions (the flue gas supply flow rate, temperature, and SO2 concentration deviation at the air inlet 506 were all less than 0.1%), two tower bodies 500 of the same diameter were built (the height of the tower bodies 500 was consistent), the same slurry was selected, that is, the slurry with the same slurry concentration and slurry chloride ion concentration was selected, the same oxidation fan was configured (to ensure the oxidation fan flow rate), different slurry circulation pumps 504 (based on the calculation and selection of different atomized particle sizes) and different spray pipelines 505 (based on the calculation and selection of different atomized particle sizes) were used, and the SO2 concentration at the same air outlet 507 was ensured to be consistent for the test, and the circulation pump 504 flow rate, absorption tower operation resistance and comprehensive energy consumption data were obtained, and the particle size-circulation pump 504 flow rate curve ( Figure 2 ), particle size-absorption tower operation resistance curve ( Figure 3 ) and particle size-comprehensive energy consumption (the sum of the power consumption of the circulation pump 504 and the power consumption converted from resistance) curve ( Figure 4 ), it can be seen from the curve that when the particle size reaches 1300μm, the power consumption of the absorption tower system reaches the minimum value, but the existing absorption tower system generally uses a large-flow, low-atomization-effect nozzle, and its atomized particle size is generally less than or equal to 1900μm. Based on this nozzle, the nozzle atomization effect can be improved by increasing the nozzle back pressure (i.e., reducing the atomized particle size), but it will also increase the power consumption of the slurry circulation pump 504, and at the same time increase the resistance of the single-layer spray layer, thereby increasing the energy consumption of the exhaust fan of the electrolytic aluminum plant.

[0041] Based on this, the present application discloses a nozzle 10, which is used in the absorption system constructed as above and is configured to reduce the particle size to 1300 μm while maintaining the existing nozzle back pressure, thereby reducing the overall energy consumption of the absorption tower system without increasing the flow rate of the circulation pump 504 and ensuring the overall desulfurization effect of the absorption tower system.

[0042] In some embodiments, reference Figure 5 and 6The nozzle comprises a main body 100, a liquid inlet 300 and a liquid outlet 400, wherein the liquid inlet 300 is configured to be docked with a spray pipeline 505 in the absorption tower system to realize the installation of the nozzle 10 as a whole, and at the same time, the main body 100 is provided with two liquid inlets 103 cooperating with the liquid inlet 300 and a liquid outlet 104 cooperating with the liquid outlet 400. When the absorption system is running, the external slurry flows into the liquid inlet 300 through the spray pipeline 505, and enters the main body 100 from the two liquid inlets 103 on the main body 100 and collides therewith. After the collision, the slurry flows into the liquid outlet 400 through the liquid outlet 104 on the main body 100 and is output to realize the atomization of the slurry. Specifically, a cylindrical cavity is defined in the main body 100, and comprises a top wall 101 and a bottom wall 102 arranged at intervals in the axial direction. At this time, the liquid inlet 300 is constituted by the top of the main body 100. The center position of the wall 101 extends in the axial direction to form a cylindrical sleeve. Correspondingly, the two liquid inlets 103 are formed on the top wall 101 of the main body 100, and the two liquid inlets 103 are centrally symmetrically arranged about the center point of the top wall 101, and a single liquid inlet 103 is extended along the edge line of the liquid inlet portion 300, and includes a first end 103c and a second end 103d. In some embodiments, while the liquid inlet 103 extends from the first end 103c to the second end 103d, the width of the liquid inlet 103 gradually decreases (that is, the distance between the outer edge 103a and the inner edge 103b of the liquid inlet 103 gradually decreases from the first end 103c to the second end 103d in the subsequent process). In some embodiments, the ratio of the width of the first end 103c of the liquid inlet 103 to the diameter of the top wall 101 of the main body 100 is between 1:25 and 1:30, so as to improve the wall adhesion effect of the slurry. Figure 5 and Figure 6The liquid inlet 103 also has an inner edge 103b and an outer edge 103a arranged at a distance. Exemplarily, the outer edge 103a of the liquid inlet 103 coincides with the lower edge line of the liquid inlet portion 300, and the inner edge 103b of the liquid inlet 103 is an arc line. Correspondingly, the nozzle 10 also includes a channel structure 200, which includes a side channel portion 201 formed by vertically extending from the inner edge 103b of the liquid inlet 103 and a top channel portion 202 horizontally extending from the upper edge of the side channel portion 201 and contacting the liquid inlet portion 300. At this time, the wall of the liquid inlet portion 300 is in contact with the side channel portion 201 and the top channel portion 202. The two top channel portions 202 together form a channel structure 200. Under the restriction of the channel structure 200, when the slurry flows in through the liquid inlet 103, it can only flow along the extension direction of the liquid inlet 103. At the same time, since the two liquid inlets 103 are centrally symmetrically arranged, the flow directions of the slurry flowing into the inner cavity of the main body 100 through the two liquid inlets 103 are opposite. The two streams of slurry collide in the inner cavity of the main body 100 to reduce the slurry particle size, that is, the purpose of reducing the atomized particle size is achieved. In some embodiments, the angle between the top channel portion 202 and the horizontal plane is 8 to 10°, thereby increasing the centrifugal force of the slurry vortex and further improving the atomization effect of the slurry.

[0043] Reference Figure 5 The liquid outlet 104 is configured as a circular notch formed at the center of the bottom wall 102 of the main body 100. Correspondingly, the liquid outlet 400 is formed by the edge of the liquid outlet 104 extending in the axial direction away from the main body 100. In some embodiments, the liquid outlet 400 includes a first section 400a which extends inwardly in the radial direction while extending away from the main body 100 in the axial direction, and a second section 400b which expands outwardly in the radial direction while extending away from the main body 100 in the axial direction. In some embodiments, the generatrix of the first section 400a is an arc line, and the generatrix of the second section 400b is a straight line segment. By designing the arc-shaped first section 400a, the outflow of the slurry can be made more uniform, and the atomized particle size output through the nozzle 10 can be ensured to be ≤1300μm, thereby reducing the power consumption by about 1kwh / (ht aluminum) compared with the existing electrolytic aluminum wet desulfurization process.

[0044] In the description of the present invention, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In the present invention, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine different embodiments or examples described in the present invention and features of different embodiments or examples without contradiction.

[0045] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A nozzle, characterized in that: include: A main body (100), wherein a cylindrical cavity is defined in the main body (100) and comprises a top wall (101) and a bottom wall (102) arranged at intervals in the axial direction; The liquid inlet portion (300) is formed as a cylindrical body extending from the center of the top wall (101) of the main body (100) in the axial direction; Two liquid inlets (103) are formed on the top wall (101) of the main body (100), the two liquid inlets (103) are centrally symmetrically arranged about the center point of the top wall (101) of the main body (100), and each of the liquid inlets (103) has an outer edge (103a) extending along the lower edge of the liquid inlet (300) and an inner edge (103b) spaced apart from the outer edge (103a); A liquid outlet (104) is formed at the center of the bottom wall (102) of the main body (100); The channel structure (200) comprises a side channel portion (201) formed by vertically extending from the inner edge (103b) and a top channel portion (202) horizontally extending from the upper edge of the side channel portion (201) and contacting the liquid inlet portion (300).

2. A nozzle according to claim 1, characterized in that: The included angle between the top channel portion (202) and the horizontal plane is 8-10°.

3. A nozzle according to claim 1 or 2, characterized in that: The liquid inlet (103) has a first end (103c) and a second end (103d), and the distance between the outer edge (103a) and the inner edge (103b) of the liquid inlet (103) gradually decreases from the first end (103c) to the second end (103d).

4. A nozzle according to claim 3, characterized in that: At the first end (103c) of the liquid inlet (103), the ratio between the distance between the outer edge (103a) and the inner edge (103b) of the liquid inlet (103) and the diameter of the top wall (101) of the main body (100) is 1:25 to 1:

30.

5. A nozzle according to claim 1, characterized in that: The nozzle further comprises a liquid outlet portion (400), wherein the liquid outlet portion (400) is formed by extending the edge of the liquid outlet (104) in the axial direction away from the main body portion (100).

6. A nozzle according to claim 5, characterized in that: The liquid outlet (104) is a circular notch formed at the center of the main body (100).

7. A nozzle according to claim 6, characterized in that: The liquid outlet portion (400) includes a first section (400a) that contracts inwardly in a radial direction while extending away from the main body portion (100) in an axial direction, and a second section (400b) that expands outwardly in a radial direction while extending away from the main body portion (100) in an axial direction.

8. A nozzle according to claim 7, characterized in that: The generatrix of the first section (400a) is an arc line.

9. A wet desulfurization process absorption tower system, characterized in that: include: A tower body (500) is defined therein with a purification zone (501) and a liquid storage zone (502) distributed vertically, and the tower body (500) is provided with an air inlet (506) and an air outlet (507) distributed vertically; At least one cycle unit, a single cycle unit comprises: A spray pipeline (505) is arranged in the purification zone (501), and the spray pipeline (505) is provided with a plurality of nozzles as described in claims 1 to 8 arranged along the cross section of the purification zone (501); A supply pipeline (503) is provided with a pump (504), and one end of the supply pipeline (503) is connected to the spray pipeline (505), and the other end is communicated with the liquid storage area (502).

10. A wet desulfurization process absorption tower system according to claim 9, characterized in that: The circulation units are arranged in plurality, and the spray pipelines (505) in the plurality of circulation units are arranged at intervals in the height direction of the tower body (500).

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