Washing nozzle for washing ammonium phosphate tail gas

Abstract

The utility model discloses a washing nozzle for washing ammonium phosphate tail gas, which comprises a flange, a nozzle cylinder connected on the flange and a flow guide disc fixed at the movable end of the nozzle cylinder, the flow guide disc comprises two guide sheets which are symmetrically arranged along the axis center of the nozzle cylinder, the two guide sheets cover the port of the nozzle cylinder, and the whole guide sheets are S-shaped. The top end of the guide piece is bent upwards. The effects of relieving the speed of washing the nozzle structure and improving the spraying quality are achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of washing nozzles, in particular to a washing nozzle used for washing phosphate ammonium tail gas. Background Art

[0002] In the production of phosphate fertilizers using phosphoric acid, ammonia, sulfuric acid, etc. as raw materials, the exhaust gas contains a large amount of dust, fluorine, sulfur dioxide, ammonia and nitrogen oxides, among which: fluorine is brought in as raw material, sulfur dioxide is brought in as dry gas, ammonia is brought in as raw material, and nitrogen oxides are brought in as raw material. These emissions in the exhaust gas not only pollute the environment but also cause production cost losses. All production enterprises use washing methods (acid washing, water washing process, and acid + water washing process) to purify the exhaust gas, and the purification process and equipment are constantly updated. Among them, the washing nozzle is the main equipment, which is needed no matter which method is used. Selecting a suitable washing nozzle can fully cover and wash the exhaust gas to achieve purification and recovery requirements.

[0003] The nozzles currently used include spiral nozzles, vortex nozzles and MP large channel solid cone nozzles, but they have the following defects:

[0004] 1. The principle of the spiral structure nozzle is that the high-speed rotating liquid (or slurry) is transformed into tiny liquid droplets and sprayed out to form a mist after being tangent to and colliding with the continuously decreasing spiral surface under the action of centrifugal force; however, its atomization surface is relatively scattered, and the direction of the droplet flow is irregular after being tangent to and colliding with the spiral surface. The direction of the droplet, that is, the concentration of the spray surface, is uncontrollable, which will cause the droplet to fail to fully wrap the medium gas, and there will be blank areas in the stroke during the washing process, and the washing effect and efficiency will not reach the target value.

[0005] 2. The principle of the vortex nozzle is to accelerate and spray the liquid by using the vortex. The vortex is a rotating flow state, which can accelerate the fluid rotation. The structure of the vortex nozzle usually includes a conical nozzle opening and a central cylinder. When the fluid passes through the nozzle opening, a rotating vortex will be formed, thereby accelerating the fluid to achieve the purpose of gas washing. However, its defect is that the atomization range is relatively limited, mainly spraying toward the front of the nozzle, suitable for spraying in a specific area, so this type of nozzle is a blind area outside the spray area or the intersection area when washing the gas in the pipeline.

[0006] 3. The MP large-channel solid cone nozzle spray has a uniform droplet distribution on a regular circular spray surface. The centrifugal motion of the liquid is achieved through the vortex guide disk inside the nozzle. The nozzle caliber and the interaction between the liquid that produces the rotating motion and the vortex guide disk make the atomized droplets of this type of nozzle large. The axial flow solid cone nozzle has a very wide flow range and a variety of spray angles are available. However, in the phosphate fertilizer industry, the tail gas often contains fertilizer dust, ammonia, etc. The production raw material is phosphoric acid, which will bring in a large amount of impurities. The impurities in phosphoric acid, washing liquid slurry, etc. will form a liquid phase static zone at the angle between the nozzle guide disk and the inner wall of the cylindrical nozzle body (the guide disk is an arc-shaped structure welded downward to the inner wall of the nozzle body). At this time, the metal impurities in the acid, the metal impurities in the slurry, and the slurry crystals will gradually precipitate and scale in this static zone until the nozzle is blocked. After scaling, the nozzle atomization spray surface forms a partition area, which makes the atomization surface disconnected or divided, so that there is a blank area for tail gas washing, which affects the washing effect, causes environmental protection to exceed the standard, and the raw material yield is low. Generally, the scaling rate is determined by the selection of impurity content in the phosphoric acid raw material for phosphate fertilizer production. The worse the quality of phosphoric acid, the shorter the nozzle cleaning cycle. Summary of the invention

[0007] The technical problem to be solved by the utility model is that there is a liquid phase static area at the end of a large-channel solid cone nozzle, which is prone to scaling in the liquid phase static area during long-term operation and needs to be cleaned or replaced regularly.

[0008] In order to solve the above technical problems, the technical solution adopted by the utility model is: a washing nozzle for washing phosphate ammonium tail gas, including a flange, a nozzle barrel connected to the flange and a guide plate fixed to the movable end of the nozzle barrel, the guide plate includes two guide plates arranged symmetrically along the axis of the nozzle barrel, the two guide plates cover the ports of the nozzle barrel, and the guide plates are S-shaped as a whole, and the top of the guide plates are bent upward.

[0009] Preferably, a gap is provided between the movable end of the nozzle barrel and the top end of the guide plate, and a transition section is provided inside the movable end of the nozzle barrel.

[0010] Preferably, a side of the guide plate close to the axis of the nozzle barrel is higher than a side close to the inner wall of the nozzle barrel.

[0011] Preferably, an arc-shaped extension section is provided between the top end of the guide piece and the inner side wall of the nozzle tube.

[0012] 1. The utility model provides a washing nozzle for washing phosphate ammonium tail gas. The guide piece in the nozzle barrel is set to an S-shaped structure. The guide piece is fixed to one side of the inner wall of the nozzle barrel, and a two-way curved surface is formed at the top and the bottom. Compared with the original one-way curved surface, the top part of the guide piece can be flushed, and the static area between the guide plate and the nozzle barrel is changed into a flow area, which effectively alleviates the scaling condition at the nozzle position, achieves the purpose of extending the maintenance period, reduces the labor intensity of the staff, avoids the problem of incomplete washing due to nozzle scaling, and extends the original warranty period of 20-30 days to 8-10 months.

[0013] 2. By changing the static area at the nozzle barrel into a flow area, the atomization spray area is increased, the efficiency of tail gas washing is improved, and the yield of effective substances in the tail gas is increased by 4.5% on the original basis, and the yield reaches more than 99.5%. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The utility model is further described below in conjunction with the accompanying drawings and embodiments:

[0015] Figure 1 It is a structural schematic diagram of an embodiment of the utility model.

[0016] Figure 2 It is a top view of an embodiment of the utility model.

[0017] Figure 3 for Figure 2 Section view of the AA plane.

[0018] Figure 4 It is a structural schematic diagram of the spiral nozzle of prior art 1.

[0019] Figure 5 It is a structural schematic diagram of the vortex nozzle of prior art 2.

[0020] Figure 6 It is a structural schematic diagram of the prior art 3MP large channel solid cone nozzle.

[0021] In the figure: 1. flange; 2. nozzle barrel; 3. guide plate. DETAILED DESCRIPTION

[0022] like Figure 1-3 The utility model provides a washing nozzle for washing phosphate ammonium tail gas, comprising a flange 1, a nozzle barrel 2 connected to the flange 1 and a guide plate 3 fixed to the movable end of the nozzle barrel 2, the guide plate 3 comprising two guide plates symmetrically arranged along the axis of the nozzle barrel 2, the two guide plates covering the ports of the nozzle barrel 2, and the guide plates are S-shaped as a whole, and the top of the guide plates are bent upward.

[0023] The washing nozzle is specially used for tail gas washing in the production of phosphate compound fertilizer. It is suitable for fertilizer slurry, high temperature phosphoric acid (80-100℃), acid corrosion (ph2-5), and crystal corrosion. The nozzle tube 2 and flange 1 are made of 316L material, and the guide plate 3 is made of 2205 material.

[0024] The guide plate 3 at the movable port of the nozzle tube 2 is adjusted from an arc-shaped structure to an S-shaped structure, so that the top and bottom of the guide plate 3 form a bidirectional curved surface. In addition, the top of the guide plate 3 is adjusted to an upwardly inclined arc to eliminate the blank area between the top of the original arc-shaped structure and the inner wall of the nozzle tube 2.

[0025] The two guide plates in the guide plate 3 are arranged symmetrically with respect to the center, and the guide direction formed by them is also spiral. There is no relative conflicting part in the guide process, thereby eliminating the static zone caused by the impact and avoiding the formation of structures in the static zone.

[0026] like Figure 3 As shown, the spraying area of ​​the nozzle is increased. A gap is provided between the movable end of the nozzle barrel 2 and the top end of the guide plate 3, and a transition section is provided inside the movable end of the nozzle barrel 2.

[0027] By further extending the top of the guide plate 3 upward and providing a transition section on the inner side of the top of the nozzle tube 2, the distance between the top of the guide plate 3 and the movable end of the nozzle tube 2 is shortened, thereby reducing the obstruction of the nozzle tube 2 to the droplets guided through the guide plate 3, thereby expanding the spraying area of ​​the nozzle.

[0028] like Figure 3 The side of the guide plate close to the axis of the nozzle barrel 2 is higher than the side close to the inner wall of the nozzle barrel 2.

[0029] By adjusting the structure of the guide blade, the edge height of the guide blade is made smaller than the middle height, so that the liquid guided by the two guide blades will not collide in the area between the two guide blades, thereby eliminating the static area and effectively alleviating the structural rate.

[0030] As a preferred embodiment of the utility model, an arc-shaped extension section is provided between the top of the guide piece and the inner wall of the nozzle barrel 2. The extension section adopts the rotation direction along the end of the guide piece, and changes the original straight end wall of the top of the guide piece into an arc-shaped end wall, extending the length of the top of the guide piece, so that the droplets close to the edge of the nozzle barrel 2 can be separated from the guide piece from the movable end of the nozzle barrel 2.

Claims

1. A washing nozzle for washing phosphate ammonium tail gas, comprising a flange (1), a nozzle barrel (2) connected to the flange (1), and a guide plate (3) fixed to the movable end of the nozzle barrel (2), characterized in that: The guide plate (3) comprises two guide plates which are arranged symmetrically along the axis of the nozzle barrel (2), the two guide plates cover the ports of the nozzle barrel (2), and the guide plates are generally S-shaped, with the top ends of the guide plates bending upward.

2. A washing nozzle for washing phosphate ammonium tail gas as claimed in claim 1, characterized in that: A gap is provided between the movable end of the nozzle barrel (2) and the top end of the guide plate (3), and a transition section is provided inside the movable end of the nozzle barrel (2).

3. A washing nozzle for washing phosphate ammonium tail gas as claimed in claim 1, characterized in that: The side of the guide plate close to the axis of the nozzle barrel (2) is higher than the side close to the inner wall of the nozzle barrel (2).

4. A washing nozzle for washing phosphate ammonium tail gas as claimed in claim 1, characterized in that: An arc-shaped extension section is provided between the top end of the guide piece and the inner wall of the nozzle barrel (2).

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