Detachable wave-shaped throat pipe of jet washer and optimization design method

Abstract

The invention discloses a detachable wave-shaped throat pipe of a jet scrubber and an optimization method of the detachable wave-shaped throat pipe, the detachable wave-shaped throat pipe is used for being installed in a throat pipe of the jet scrubber, and the jet scrubber comprises a flue gas pipeline, a spray head assembly, an ammonia water inlet, a diffusion pipe, a throat pipe, a contraction pipe, angle steel and an ammonia water pipeline. The throat pipe is formed by connecting an upper-section straight pipe of the diffusion pipe and a lower-section straight pipe of the contraction pipe through a flange, a wave-shaped throat pipe is detachably and fixedly installed in the throat pipe, a periodic wave-shaped structure is arranged on the inner wall of the wave-shaped throat pipe in the axial direction, and the wave-shaped structure comprises arc-shaped protrusions with the wave height being 5 mm and the wave pitch being 20 mm and grooves which are alternately distributed. The corrugated throat pipe structure with the arc-shaped protrusions and the grooves alternately distributed on the inner wall is adopted, the structure can effectively disperse the concentrated scouring effect of gas-solid-liquid three-phase flow on the inner wall of the throat pipe, the local abrasion risk is remarkably reduced, and therefore the operation stability and reliability of the Venturi pipe under the complex flowing condition are improved.

Description

Technical Field

[0001] The present invention relates to a jet scrubber, and particularly to a detachable corrugated throat pipe of a jet scrubber and an optimized design method therefor. Background Art

[0002] A jet scrubber is a core device in the wet ammonia flue gas desulfurization process. Its separation efficiency, corrosion resistance and stability have an important impact on the overall desulfurization effect of the system. As a key component of the jet scrubber, the venturi tube has the problem of severe wear in the throat area due to the mixing and scouring of flue gas. In the conventional venturi tube structure, the inner wall of the throat is smooth, and the violent mixing of gas-solid two-phase causes local high-speed scouring. Moreover, it works in an acid-base environment for a long time, which aggravates the corrosion and loss of the equipment, shortens the service life, and restricts the operation efficiency and stability of the desulfurization system.

[0003] Existing solutions include adjusting the gas velocity in the throat to slow down the wear, but this will affect the gas-liquid mixing effect and reduce the separation efficiency. In addition, there is a method of using new wear-resistant materials, but its manufacturing cost is relatively high and it is difficult to promote on a large scale. At the same time, China's sulfuric acid manufacturing industry still faces a large number of flue gas treatment problems. Therefore, improving the wear resistance and separation efficiency of the throat of the venturi tube and reducing its energy consumption have become the key technical directions that need to be broken through urgently. Summary of the Invention

[0004] A detachable corrugated throat pipe of a jet scrubber proposed by the present invention adopts a corrugated throat pipe structure with alternately distributed arc-shaped protrusions and grooves on the inner wall. This structure can effectively disperse the concentrated scouring action of the gas-solid-liquid three-phase flow on the inner wall of the throat pipe, significantly reduce the risk of local wear, and thus improve the operation stability and reliability of the venturi tube under complex flow conditions.

[0005] The technical solution disclosed by the present invention is as follows: A detachable corrugated throat pipe of a jet scrubber is used to be installed in the throat pipe of the jet scrubber. The jet scrubber includes a flue gas pipeline, a spray head assembly, an ammonia water inlet, a diffuser pipe, a throat pipe, a contraction pipe, an angle steel, and an ammonia water pipeline. The throat pipe is formed by connecting the upper straight pipe of the diffuser pipe and the lower straight pipe of the contraction pipe through a flange. A corrugated throat pipe is detachably and fixedly installed in the throat pipe. The inner wall of the corrugated throat pipe is provided with a periodic corrugated structure along the axial direction. The corrugated structure includes alternately distributed arc-shaped protrusions and grooves with a wave height of 5 mm and a wave pitch of 20 mm.

[0006] On the basis of the above solution, preferably, the outer diameter of the corrugated throat pipe is smaller than the inner diameter of the throat pipe, and a trapezoidal rubber ring is arranged between the two, and it is installed and fixed by an interference fit and a friction self-locking method.

[0007] On the basis of the above solution, preferably, the lower section of the outer wall of the corrugated throat pipe has a T-shaped groove, and the lower end of the inner wall of the trapezoidal rubber ring has a T-shaped mounting ring, which is installed in the T-shaped groove. The upper end diameter of the trapezoidal rubber ring is larger than the lower end diameter, which is used to achieve limit and stable positioning and prevent axial dislocation of the rubber ring during installation.

[0008] On the basis of the above solution, preferably, the trapezoidal rubber ring has a structure that is thicker at the top and thinner at the bottom. The thickness of the upper end is 13.8 - 14.3 mm, and the thickness of the bottom end is about 8 - 9 mm. After axial compression, the upper end deforms to generate radial pressure, realizing the self-locking function; the thickness of the bottom end is less than the gap between the corrugated throat pipe and the throat pipe, which is convenient for installation.

[0009] On the basis of the above solution, preferably, the compression ratio of the trapezoidal rubber ring is controlled to not exceed 10%, and the total friction force is adjustable between 0.6 - 1.8 tons; by adjusting the thickness of the top end of the rubber ring, different interference fits can be achieved to meet the fixing requirements under different flow conditions.

[0010] On the basis of the above solution, preferably, the installation method of the corrugated throat pipe is as follows:

[0011] (1) Place the deformable trapezoidal rubber ring from the bottom of the contraction pipe, with the end having the T-shaped mounting ring facing downwards, and the T-shaped mounting ring part extending into the lower straight pipe.

[0012] (2) Place the corrugated throat pipe from the bottom of the contraction pipe into the trapezoidal rubber ring, with the end having the T-shaped groove 10 facing downwards, and make the T-shaped mounting ring cooperate with the trapezoidal rubber ring to form a corrugated throat pipe assembly through manual alignment.

[0013] (3) Apply an axial downward pulling force to the corrugated throat pipe assembly through a puller tool, so that it slides along the lower straight pipe of the contraction pipe. When the outer diameter of the bottom end of the corrugated throat pipe assembly is close to the inner diameter of the lower straight pipe, stop pulling to complete the preliminary fastening, and leave a gap space of 1 - 2 mm to avoid deformation of the bottom end of the corrugated throat pipe assembly and the generation of reverse friction force when the trapezoidal rubber ring enters the diffuser pipe, which will push the corrugated throat pipe assembly back.

[0014] (4) Then insert the lower end of the corrugated throat pipe assembly into the upper straight pipe of the diffuser pipe, and use the lifting mechanism to jack up the diffuser pipe so that the flange of the upper straight pipe contacts the flange of the lower straight pipe to complete the assembly of the diffuser pipe and the contraction pipe.

[0015] (5) Insert a large-sized puller from the bottom of the diffuser pipe and pull down the corrugated throat pipe assembly to complete the assembly of the corrugated throat pipe.

[0016] An optimization method for the detachable corrugated throat pipe of a jet scrubber, including:

[0017] (1) Determination of structural parameters: Based on the overall structural dimensions of the Venturi tube, determine the throat length and the allowable maximum wall thickness, and set the basic parameters of the corrugated structure, including a wave height of 5 mm, and the waveform distribution is uniformly distributed along the axial direction. Select different wave pitches of 20 mm, 40 mm, and 100 mm as optimization variables;

[0018] (2) Flow field simulation modeling: Under simplified working conditions, use single-phase cold air as the working medium to construct a three-dimensional fluid model of the Venturi tube, and complete the mesh division through the MESH module to ensure that the average mesh quality is not less than 0.9;

[0019] (3) Setting of boundary conditions: Set the velocity inlet boundary condition, with an inlet velocity of about 10 m / s; the outlet is a pressure outlet, and the outlet static pressure is the atmospheric pressure; assume that the wall is a rigid no-slip boundary and ignore the influence of wall roughness;

[0020] (4) Simulation analysis: Conduct flow field simulations on the corrugated throats with different wave pitches respectively to obtain gas velocity distribution, pressure distribution, and pressure drop data;

[0021] (5) Performance comparison and judgment: By comparing the average gas velocity and pressure changes at key cross-sections such as the throat, diffuser section, and outlet, analyze the influence of different wave pitch structures on the gas-solid separation efficiency and energy consumption;

[0022] (6) Determination of optimal parameters: According to the simulation results, when the wave pitch is 20 mm, the gas velocity in the throat is the highest, the negative pressure effect is the best, the pressure recovery effect is the most significant, and the pressure drop is the smallest, and the comprehensive performance is the best. Determine it as the optimal structural parameter configuration of the corrugated throat.

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

[0024] 1. Compared with the throat structure with a smooth cylindrical inner wall used in the traditional way, the present invention adopts a corrugated throat structure with alternately distributed arc-shaped protrusions and grooves on the inner wall. This structure can effectively disperse the concentrated scouring effect of the gas-solid-liquid three-phase flow on the inner wall of the throat, significantly reducing the risk of local wear, thereby improving the operation stability and reliability of the Venturi tube under complex flow conditions.

[0025] 2. Compared with the throat structure formed by splicing a contraction tube and a diffuser tube in the prior art, if a complex corrugated convex-concave structure is directly machined on the overall Venturi tube, the processing process is complicated and the manufacturing cost is high; while the corrugated throat in the present invention is designed as an independent modular component, which can be directly assembled to the throat position after high-precision manufacturing outside, avoiding traditional welding or complex assembly processes, and significantly reducing the manufacturing cost and assembly difficulty.

[0026] 3. The present invention is equipped with a trapezoidal rubber ring that is thicker at the top and thinner at the bottom. Under the intake condition, it cooperates with the axial force generated by the fluid pressure to automatically lock the corrugated throat pipe downward to a specified position, forming a self-locking structure, which ensures that the corrugated throat pipe is fixed within the working range of the throat pipe. When disassembly is required, simply push from the bottom upwards to easily release the self-locking and achieve rapid replacement of the corrugated throat pipe.

[0027] 4. By calculating and simulating the structural parameters of the corrugated throat pipe, the present invention optimizes the key geometric parameter - the wave pitch, and determines the optimal combination of operating parameters, providing a solid theoretical basis for the further optimized design of the Venturi tube structure.

[0028] 5. By calculating and analyzing, the effective design range of the side lengths at both ends of the trapezoidal rubber ring is determined, enhancing the adaptability and stability of the corrugated throat pipe under various working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the overall structure of the Venturi tube;

[0030] Figure 2 It is a schematic diagram of the structure of the corrugated throat pipe;

[0031] Figure 3 It is a schematic diagram of the structure of the trapezoidal rubber ring;

[0032] Figure 4 It is a schematic diagram of the working principle of the corrugated throat pipe;

[0033] Figure 5 It is a schematic diagram of the mesh division of the corrugated throat pipe;

[0034] Figure 6 It is a cloud map of different cross-sections of the flow field of the corrugated throat pipe;

[0035] Figure 7 It is a cloud map of the velocity comparison of the corrugated throat pipe;

[0036] Figure 8 It is a cloud map of the pressure comparison of the corrugated throat pipe;

[0037] Figure 9 It is a cloud map of the velocity comparison of the corrugated throat pipes with different wave pitches;

[0038] Figure 10 It is a cloud map of the pressure comparison of the corrugated throat pipes with different wave pitches;

[0039] Figure 11 It is a cloud map of the velocity curve of the corrugated throat pipes with different wave pitches;

[0040] Figure 12 It is a cloud map of the pressure curve of the corrugated throat pipes with different wave pitches. DETAILED DESCRIPTION OF THE INVENTION

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the specific embodiments of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings, and other embodiments can also be obtained.

[0042] As Figures 1-12 shown, a spray scrubber mainly includes a flue gas duct 1, a spray head assembly 2, an ammonia inlet 3, a diffuser tube 4, a throat tube 5, a contraction tube 6, an angle steel 7, an ammonia pipeline 8, a corrugated throat tube 9, a T-shaped groove 10, a trapezoidal rubber ring 11, and a T-shaped mounting ring 12.

[0043] Among them, the throat tube is formed by connecting the upper straight tube of the diffuser tube and the lower straight tube of the contraction tube through a flange.

[0044] During operation, the flue gas will enter from the flue gas duct 1. At the same time, ammonia water will be distributed from the ammonia inlet 3 to the three ammonia pipelines 8, and then enter the spray head assembly 2 and be sprayed out. The installation position of the spray head assembly 2 is higher than that of the ammonia pipeline 8 to control the same water pressure and ensure the ammonia spraying effect of the three spray heads. The ammonia pipeline 8 and the spray head assembly 2 are supported by the angle steel 7 fixed on the contraction tube 6.

[0045] The sprayed ammonia water turns into a water mist and undergoes an acid-base neutralization reaction with the sulfur-containing flue gas. The reaction formula is as follows.

[0046] SO2 + 2NH3 + H2O → (NH4)2SO3

[0047] 2(NH4)2SO3 + O2 + 2H2O → 2(NH4)2SO4

[0048] The flue gas enters the throat tube 5 from the contraction tube 6. Under the Bernoulli effect, the sulfur-containing flue gas and ammonia water are fully accelerated and mixed. Through the alternating arc protrusions on the wall surface of the corrugated throat tube 9, the concentrated erosion of stress is avoided. Then the mixed flue gas leaves from the diffuser tube 4 and enters the next separation process.

[0049] Among them, a corrugated throat tube 9 is installed at the position of the throat tube 5. The outer diameter of the corrugated throat tube 9 is slightly smaller than the inner diameter of the throat tube. A trapezoidal rubber ring 11 is installed in the gap between them. Through the cooperation of the T-shaped mounting ring 12 at the bottom of the trapezoidal rubber ring 11 and the T-shaped groove 10 at the bottom of the corrugated throat tube 9, and the self-locking effect brought by the trapezoidal structure of the trapezoidal rubber ring 11 itself, the installation of the corrugated throat tube 9 at the position of the throat tube 5 is realized.

[0050] The jet scrubber is a gas-liquid separation device. Three spray head assemblies 2, three ammonia pipelines 8, and a fixed structure angle steel 7 are installed on the contraction pipe 6. The contraction pipe 6 is connected to the throat pipe 5 and cannot be disassembled or assembled. The diffuser pipe 4 is connected to the throat pipe at the bottom of the contraction pipe 6 through a flange, thus forming a Venturi tube.

[0051] Since many pipeline structures are installed on the inner and outer walls of the contraction pipe 6, and in addition, a flue gas pipeline 1 is connected. If installed from above the contraction pipe 6, it is extremely inconvenient and may even bump into important structures. However, no structures are installed on the diffuser pipe, so an installation method for a corrugated throat pipe 9 is designed.

[0052] The outer diameter of the corrugated throat pipe 9 is 720 mm, the inner diameter is 700 mm, the wave height is 5 mm, the wave pitch is 20 mm. The inner diameter of the throat pipe 5 of the contraction pipe is 740 mm, and the height of both is 500 mm. The outer diameter of the corrugated throat pipe 9 is slightly smaller than the inner diameter of the throat pipe 5. (The outer diameter here refers to the diameter.)

[0053] Installation steps of the corrugated throat pipe:

[0054] 1. Disassemble the Venturi tube into the contraction pipe 6 and the diffuser pipe 4. First, place the trapezoidal rubber ring 11 into the lower straight pipe of the contraction pipe 6, and the T-shaped installation ring of the trapezoidal rubber ring 11 is located below the lower straight pipe.

[0055] 2. Then place the corrugated throat pipe 9 into the lower straight pipe of the contraction pipe 6. By means of manual alignment, make the T-shaped installation ring 10 cooperate with the trapezoidal rubber ring 11 to form a corrugated throat pipe assembly.

[0056] 3. Apply an axial downward pulling force to the corrugated throat pipe assembly through a puller tool, so that it slides along the lower straight pipe of the contraction pipe. When the maximum outer diameter of the corrugated throat pipe assembly exposed from the lower straight pipe is close to the inner diameter of the lower straight pipe, stop pulling to complete the preliminary tightening fixation, and leave a gap of 1 - 2 mm. This is to avoid deformation of the bottom end of the corrugated throat pipe assembly and the generation of reverse frictional force when the trapezoidal rubber ring enters the diffuser pipe 4, which will push the corrugated throat pipe assembly back.

[0057] 4. Insert the lower end of the corrugated throat pipe assembly into the upper straight pipe of the diffuser pipe 4, and use the lifting mechanism to jack up the diffuser pipe 4 so that the flange of the upper straight pipe contacts the flange of the lower straight pipe to complete the assembly of the diffuser pipe and the contraction pipe.

[0058] 5. Insert a large puller from the bottom of the diffuser pipe 4 and pull down the corrugated throat pipe assembly to complete the assembly of the corrugated throat pipe.

[0059] Among them, the top thickness of the trapezoidal rubber ring 11 can be set to 13.8 - 14.3 mm. By undergoing appropriate deformation under the action of axial load, sufficient contact pressure is generated, thereby forming a stable friction self-locking ability to effectively prevent the axial displacement of the corrugated throat pipe during the working state.

[0060] The bottom thickness is about 8 - 9 mm, slightly less than the fitting clearance (10 mm) between the corrugated throat 9 and the throat body 5, achieving clearance fit. This design takes into account both the installation convenience and disassembly feasibility of the corrugated throat assembly. At the same time, it ensures that after assembly, there is still sufficient contact area between the bottom of the trapezoidal rubber ring and the inner wall of the throat, providing the necessary friction and support force to maintain the positioning stability and sealing effect of the corrugated throat.

[0061] The corrugated throat forms a concave-convex periodic change through the geometric deformation of the inner wall structure (wave height 5 mm, wave pitch 20 mm), disturbing the high-speed air flow path. When the high-speed flue gas flows through the corrugated structure, the direction of the velocity vector changes frequently, thus effectively improving the gas-solid mixing efficiency and alleviating the problem of concentrated wall erosion. Its Venturi effect is still maintained, forming a high flow rate and negative pressure area at the throat, and effectively recovering the pressure in the diffuser section to achieve efficient separation and energy recovery.

[0062] Through multi-group data calculation and safety criterion checking, with the core limit of thickness compression rate ≤ 30%, the value range of the upper side thickness of the trapezoidal rubber ring is determined to be 12 mm to 14.3 mm, and the corresponding total friction force controllable range is 0.6 tons to 1.8 tons.

[0063] The safety factor SF usually needs to be ≥ 2 in a dynamic erosion environment. In the design manual of the jet scrubber throat, the erosion force is estimated to be 0.5 - 1.0 tons, taking 0.8 tons as the intermediate value. The total friction force needs to be at least more than 1.6 tons. Therefore, the reasonable value range of the upper side thickness of the trapezoidal rubber ring in the present invention is 13.8 - 14.3 mm.

[0064]

[0065] Calculation process:

[0066] 1. Initial outer diameter:

[0067] D 初始 =D 波形喉管 +2×t 上 =720 + 2t 上

[0068] 2. Interference:

[0069] δ=D 初始 -D 文丘里内径 =D 初始 -740

[0070] 3. Thickness compression rate:

[0071] t is the upper side thickness

[0072] 4. Upper side pressure:

[0073] E = 5 MPa (rubber elastic modulus), ν = 0.5 (Poisson's ratio of rubber)

[0074] 5. Total frictional force:

[0075] F = μ·p·A 接触 ≈0.3·p·π·D 中 ·H

[0076] μ = 0.3, H = 500 mm

[0077]

[0078]

[0079] Optimization design method and verification:

[0080] 1. Simplify the working conditions

[0081] Only consider the single-phase cold air flow field, without involving energy transfer and chemical reactions. Assume that the wall surface is rigid and has no-slip boundaries.

[0082] 2. Simplify the Venturi tube model

[0083] The Venturi tube is mainly composed of a converging tube 6, a throat tube 5, and a diverging tube 4. Usually, the inlet pipe diameter D1 is the same as the outlet diameter D3. The diameter ratio (i.e., the ratio of the throat diameter D2 to the inlet pipe diameter D1) is between 0.25 - 0.5. The cone angle θ1 of the converging section is usually between 10° - 30°, and the cone angle θ2 of the diverging section is usually controlled within 7° - 10°. The structural parameters of the Venturi tube are shown in the following table. The corrugated throat tube is restricted by the height and thickness of the throat tube of the conventional Venturi tube. Therefore, the designed wave height is 5 mm and the wave pitch is 20 mm.

[0084] Table of Venturi tube structural parameters

[0085]

[0086] 3. Mesh generation

[0087] The model is meshed through the MESH module. After mesh generation, the average orthogonal quality of the mesh of the Venturi tube is 0.92, the number of mesh nodes is 6572, and the minimum mesh has no negative value. The mesh generation meets the analysis requirements.

[0088] 4. Boundary conditions

[0089] In this study, cold air was used as the single-phase medium. During the calculation process, the energy transfer between the system and the outside world was not considered. It was assumed to be a rigid wall, and the no-slip boundary condition was adopted, ignoring the influence of wall roughness on the flow field. According to the exhaust gas flow rate in the work and the intake pipe area of the Venturi tube, the intake velocity was approximately 10 m / s. The velocity inlet was used to set a uniform velocity distribution to ensure the stability of the inlet flow field. The pressure outlet was used to set the outlet static pressure to the atmospheric pressure to simulate the open environment under actual working conditions.

[0090] Table of structural parameters of the Venturi tube

[0091]

[0092] 5. Calculation model

[0093] Turbulent flow follows the three basic laws of mass conservation, momentum conservation, and energy conservation. Therefore, the basic equations of turbulence include the mass conservation equation, the momentum conservation equation, and the energy conservation equation. This study focuses on the flow field in the single-phase gas state, using cold air as the single-phase medium. During the calculation process, the energy transfer between the system and the outside world is not considered. Therefore, the basic equations in the Cartesian coordinate system are as follows:

[0094] (1) Mass conservation equation:

[0095]

[0096] (2) Momentum conservation equation:

[0097]

[0098] (3) Energy conservation equation:

[0099]

[0100] In the formula, u, ρ, T, p, μ, Pr, and Prt represent the velocity, density, temperature, pressure, dynamic viscosity, turbulent viscosity of the fluid air, respectively.

[0101] 6. Comparison of technical indicators (as Figure 6 shown)

[0102] To verify the separation performance of the two Venturi tubes, six different height sections at X = 0 m, 2.1 m, 2.7 m, 4 m, 5.2 m, and 7.3 m were taken, corresponding to the intake port, intake pipe, contraction pipe, throat pipe, diffuser pipe, and outlet, respectively. The differences in the separation performance between the Venturi tube with a corrugated throat and the Venturi tube were compared and analyzed, focusing on discussing the throat gas velocity, pressure, and pressure drop. The results are as Figure 7 shown.

[0103] Table of average gas velocity data for each plane of the Venturi tube with a corrugated throat and the conventional Venturi tube

[0104]

[0105] (1) When the speed range is 0 - 80 m / s, the high-speed area of the venturi tube of the corrugated throat tube is red, showing a regular pentagon distribution with a large area and a more uniform flow field distribution. While the high-speed area of the [comparison object] is orange, showing a triangular distribution with a small area. In addition, the velocity values at the throat cross-section of the venturi tube of the corrugated throat tube are generally higher, and the velocity values at the throat cross-section of the [comparison object] are relatively lower, indicating that the design of the corrugated throat tube can effectively maintain high-speed flow, which is beneficial to the mixing and separation of gas-solid two phases.

[0106] (2) The venturi tube of the corrugated throat tube performs better in terms of throat gas velocity, which is 66.137347 m / s, and can maintain a higher throat flow velocity, which is beneficial to improving the separation efficiency.

[0107] The average pressure data of each cross-section of the venturi tube of the corrugated throat tube and the conventional venturi tube are shown in the following table, and the pressure comparison nephogram of the throat cross-section is as Figure 8 shown, and the conclusions are as follows:

[0108] (1) When the pressure range is -3000 Pa to 1000 Pa, the overall area color of the pressure area of the venturi tube of the corrugated throat tube is blue, while the overall pressure area of the conventional venturi tube gradually changes from light blue at the center. Therefore, the pressure distribution of the venturi tube of the corrugated throat tube is more uniform.

[0109] (2) At the intake port and the intake pipe cross-section, the pressure of the venturi tube of the corrugated throat tube is significantly lower than that of the conventional venturi tube, which is 226.96137 Pa. At the throat cross-section, the throat negative pressure of the venturi tube of the corrugated throat tube is greater, which is -2419.6315 Pa, fully playing the Venturi effect. At the diffuser port and the outlet cross-section, the pressure recovery effect of the diffuser tube of the venturi tube of the corrugated throat tube is better, which is -614.22921 Pa, and is closest to the atmospheric pressure.

[0110] (3) The pressure drop of the venturi tube of the corrugated throat tube is 2644.06684 Pa, while the pressure drop of the conventional venturi tube is 2642.83155 Pa, with a difference of less than 2 Pa. However, the venturi tube of the corrugated throat tube has better performance.

[0111] The average pressure data table of each plane of the venturi tube of the corrugated throat tube and the conventional venturi tube

[0112]

[0113] It should be noted that the text in brackets in item (1) of and item (1) of needs to be filled with the specific content of the "comparison object" according to the actual situation in the original text. Since it is not clearly given in the current text, it is temporarily replaced with "[comparison object]".Through the comparative analysis of key parameters such as the gas velocity in the throat, pressure distribution, and pressure drop, it is found that the gas velocity in the throat of the venturi tube with a corrugated throat is higher, which can effectively enhance the mixing of gas-solid two phases and improve the separation efficiency. In addition, the pressure distribution of the venturi tube with a corrugated throat is more uniform, which can reduce local stress concentration and extend the service life of the equipment. The pressure drop of the venturi tube with a corrugated throat is slightly lower than that of the conventional venturi tube, which is almost negligible, and the negative pressure effect is more obvious, and the pressure recovery effect in the diffuser section is better.

[0114] Therefore, on the premise of meeting the requirements such as separation efficiency and pressure loss, the venturi tube with a corrugated throat has more advantages than the conventional venturi tube and can be used as an optimal solution.

[0115] 7. Optimization of Key Structural Parameters

[0116] The main design parameters of the corrugated throat include wave height, wave pitch, and wave number. Due to the limitation of the throat wall thickness, it is impossible to study the parameters of multiple wave heights. Moreover, the wave number is more suitable for studying a single waveform. In addition, if the wave number does not exactly cover the throat, it does not meet the research purpose. Therefore, this paper selects the wave pitch as the main structural parameter to be optimized.

[0117] Based on the length of the throat being 500 mm, in order to facilitate research and modeling, the factors of 500 are selected as the design principle, and too small or too large wave pitches are removed, thus designing three suitable wave pitches of 20 mm, 40 mm, and 100 mm.

[0118] The optimization design of the corrugated throat is discussed and analyzed from three aspects: the gas velocity in the throat, pressure, and pressure drop, as Figure 9 、 10 shown. The conclusions are as follows:

[0119] (1) The colors and distribution states of the velocities and pressures of the three wave pitches are extremely similar and cannot be easily distinguished.

[0120] (2) The gas velocities in the throats of the three wave pitches are very close, all around 66.13 m / s, and the wave pitch has little effect on the gas velocity in the throat. However, in the diffuser and the outlet, the designs of different wave pitches have a more obvious effect on the flow velocity. The gas velocity in the diffuser with a 20-mm wave pitch is 36.787849 m / s, which is significantly higher than those with 40-mm and 100-mm wave pitches. Therefore, the 20-mm wave pitch performs better in terms of the gas velocity in the throat and the gas velocity in the diffuser.

[0121] (3) Different wave pitches have a great influence on the pressure distribution inside the throat tube. At the air inlet and the intake pipe, as the wave pitch increases, the pressure value gradually rises. While at the throat tube cross-section, the negative pressure value gradually decreases with the increase of the wave pitch. The structure with a smaller wave pitch can more effectively generate the Venturi effect and enhance the suction effect on the gas-solid two-phase flow. At the diffuser tube and the air outlet, the pressure recovery effect with a wave pitch of 20 mm is better than that of 40 mm and 100 mm.

[0122] (4) By calculating the pressure drop, it is found that the pressure drop with a wave pitch of 20 mm is the smallest, which is 2644.06684 Pa, while the pressure drop with a wave pitch of 100 mm is the largest. The smaller the wave pitch, the lower the pressure drop.

[0123] Based on the conclusions of the above analysis, and Figure 11 、 12 , the air velocity of the throat tube with a wave pitch of 40 mm is the highest, but the difference is small and almost negligible. The throat tube with a wave pitch of 20 mm has the largest negative pressure and a better pressure recovery effect in the diffuser tube. In addition, the pressure drop with a wave pitch of 20 mm is the smallest. Therefore, a wave pitch of 20 mm is the best parameter choice for the corrugated throat tube Venturi tube.

[0124] Average velocity data table of each plane of the corrugated throat tube Venturi tube with different wave pitches

[0125]

[0126] Average pressure data table of each plane of the corrugated throat tube Venturi tube with different wave pitches

[0127]

[0128] It should be noted that the above embodiments can be freely combined according to needs. The above is only the preferred embodiment of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A detachable corrugated throat of a jet scrubber, characterized in that: It is used to be installed in the throat of the jet scrubber. The jet scrubber includes a flue gas duct, a nozzle assembly, an ammonia water inlet, a diffuser, a throat, a contraction tube, an angle steel, and an ammonia water pipeline. The throat is formed by connecting the upper straight pipe of the diffuser and the lower straight pipe of the contraction tube through a flange. A corrugated throat is detachably fixedly installed in the throat. The inner wall of the corrugated throat is provided with a periodic corrugated structure along the axial direction. The corrugated structure includes arc-shaped protrusions and grooves with a wave height of 5 mm and a wave distance of 20 mm alternately distributed.

2. A detachable corrugated throat of a jet scrubber according to claim 1, characterized in that: The outer diameter of the corrugated throat is smaller than the inner diameter of the throat, and a trapezoidal rubber ring is arranged between the two, which are installed and fixed by interference fit and friction self-locking.

3. The detachable corrugated throat of a jet scrubber according to claim 1, characterized in that: The lower section of the outer wall of the corrugated throat has a T-slot, and the lower end of the inner wall of the trapezoidal rubber ring has a T-shaped mounting ring. The T-shaped mounting ring is installed in the T-slot. The upper end diameter of the trapezoidal rubber ring is larger than the lower end diameter, which is used to achieve limiting and stable positioning to prevent axial dislocation of the rubber ring during installation.

4. A detachable corrugated throat of a jet scrubber as claimed in claim 1, characterized in that: The trapezoidal rubber ring has a thick upper part and a thin lower part structure, with a thickness of 13.8-14.3 mm at the upper end and a thickness of 8-9 mm at the bottom end. After axial compression, the upper end deforms to generate radial pressure to achieve a self-locking function; the thickness of the bottom end is smaller than the gap between the corrugated throat and the throat pipe, which is convenient for installation.

5. The detachable corrugated throat of a jet scrubber according to claim 1, characterized in that: The compression rate of the trapezoidal rubber ring is controlled to be no more than 10%, and the total friction force is adjustable between 0.6 and 1.8 tons; by adjusting the thickness of the top of the rubber ring, different interference fits can be achieved to meet the fixing requirements under different flow conditions.

6. A detachable corrugated throat of a jet scrubber as claimed in claim 1, characterized in that: Installation method of corrugated pipe: (1) Insert the deformable trapezoidal rubber ring from the bottom of the shrink tube, with the end with the T-shaped mounting ring facing downward and the T-shaped mounting ring extending into the lower straight tube; (2) Place the corrugated throat from the bottom of the shrink tube into the trapezoidal rubber ring, with the end with the T-slot 10 facing downward, and manually align the T-shaped mounting ring and the trapezoidal rubber ring to form a corrugated throat assembly; (3) Use the puller to pull the corrugated throat assembly downward so that the corrugated throat assembly and the lower straight tube of the shrink tube are initially tightly fixed; (4) Insert the lower end of the corrugated throat assembly into the upper straight pipe of the diffuser, and use the lifting mechanism to push up the diffuser so that the flange of the upper straight pipe contacts the flange of the lower straight pipe, thus completing the assembly of the diffuser and the contraction pipe; (5) Insert a large puller from the bottom of the diffuser and pull down the corrugated throat assembly to complete the assembly of the corrugated throat.

7. A method for optimizing a detachable corrugated throat of a jet scrubber, characterized in that: include: (1) Determination of structural parameters: Based on the overall structural dimensions of the Venturi tube, the throat length and the maximum allowable wall thickness are determined, and the basic parameters of the waveform structure are set, including a wave height of 5 mm, uniform waveform distribution along the axial direction, and different wave distances of 20 mm, 40 mm, and 100 mm are selected as optimization variables; (2) Flow field simulation modeling: Under simplified working conditions, single-phase cold air is used as the working medium to construct a three-dimensional fluid model of the Venturi tube, and the mesh is divided through the MESH module to ensure that the average mesh quality is not less than 0.9; (3) Boundary condition setting: Set the velocity inlet boundary condition, the air inlet velocity is about 10 m / s; the outlet is a pressure outlet, and the outlet static pressure is atmospheric pressure; assume that the wall is a rigid no-slip boundary, and ignore the influence of wall roughness; (4) Simulation analysis: Flow field simulation is performed on corrugated throats with different wave pitches to obtain gas velocity distribution, pressure distribution, and pressure drop data; (5) Performance comparison and judgment: By comparing the average gas velocity and pressure changes in key sections such as the throat, diffuser and outlet, the effects of different wave length structures on gas-solid separation efficiency and energy consumption are analyzed; (6) Determination of optimal parameters: According to the simulation results, when the wave pitch is 20 mm, the throat gas velocity is the highest, the negative pressure effect is the best, the pressure recovery effect is the most significant, and the pressure drop is the smallest. The overall performance is the best, which is determined to be the optimal structural parameter configuration of the corrugated throat.

Images