A spray device for dry desulfurization

Abstract

The application relates to the technical field of dry desulfurization, and particularly provides a spraying device for dry desulfurization, which comprises the following parts: a nozzle inlet end connected with a high specific surface calcium hydroxide conveying pipeline, wherein the flow passage cross-sectional area of the nozzle is smaller than that of the conveying pipeline; a mixing chamber inlet end is arranged at intervals from the nozzle outlet end, wherein the flow passage cross-sectional area of the mixing chamber inlet end is larger than that of the nozzle outlet end; a throat inlet end is connected with the mixing chamber outlet end, wherein the flow passage cross-sectional area of the throat inlet end is smaller than that of the mixing chamber inlet end; a diffusion pipe inlet end is connected with the throat outlet end, wherein the flow passage cross-sectional area of the diffusion pipe outlet end is larger than that of the diffusion pipe inlet end; a leading-out section inlet end is connected with the diffusion pipe outlet end; an air distribution cone is arranged at the leading-out section outlet end, and an annular outlet is formed between the air distribution cone and the inner wall of the leading-out section outlet end. The application improves the uniformity of the mixing of the high specific surface calcium hydroxide and flue gas through the continuous change of the flow passage cross-sectional areas of multiple stages, so as to improve the utilization rate of the high specific surface calcium hydroxide.

Description

Technical Field

[0001] This application relates to the field of dry flue gas desulfurization technology, and in particular to an injection device for dry desulfurization. Background Technology

[0002] Dry desulfurization is a key technology for achieving efficient purification of sulfur dioxide in the field of flue gas treatment. Its core process involves fully mixing and reacting the desulfurizing agent with the flue gas in a gas-solid two-phase reaction. Among them, high specific surface area calcium hydroxide is a key material for improving desulfurization efficiency due to its extremely high specific surface area and adsorption activity. The degree of uniformity of mixing high specific surface area calcium hydroxide with flue gas directly determines the calcium-sulfur ratio, solid waste emissions and overall operating cost of the desulfurization system.

[0003] Currently, most dry desulfurization processes use pneumatic conveying combined with injection devices to inject and mix high specific surface area calcium hydroxide. These devices typically include conveying pipes, nozzles, and a simple mixing zone. The working principle is to accelerate the high specific surface area calcium hydroxide through the nozzle and inject it into the flue. The airflow ejection effect promotes the desulfurizer to contact the flue gas and undergo a preliminary reaction, thereby completing the sulfur dioxide adsorption process.

[0004] However, during operation, existing injection devices suffer from insufficient mixing paths between the nozzle jet and flue gas, and imperfect flow field organization. This results in uneven distribution of high specific surface area calcium hydroxide in the flue gas, forming areas with excessively high or low concentrations. Consequently, the effective reaction area is reduced, and some high specific surface area calcium hydroxide is discharged without participating in the reaction. Ultimately, this leads to a persistently high calcium-to-sulfur ratio, increased solid waste generation, and difficulty in effectively controlling operating energy consumption and material costs. As a result, these devices fail to meet the stringent requirements for uniform mixing under high-standard desulfurization efficiency. Utility Model Content

[0005] This application provides an injection device for dry desulfurization to solve the technical problems of high calcium-sulfur ratio, large amount of desulfurization solid waste and high operating cost caused by uneven mixing of high specific surface area calcium hydroxide with flue gas in existing injection devices.

[0006] To achieve the above objectives, this application provides an injection device for dry desulfurization, comprising:

[0007] The nozzle has its inlet end connected to a high specific surface area calcium hydroxide conveying pipeline, and the flow cross-sectional area of ​​the nozzle is smaller than that of the conveying pipeline.

[0008] A mixing chamber is provided with its inlet end and the nozzle outlet end spaced apart, and the flow cross-sectional area of ​​the mixing chamber inlet end is larger than the flow cross-sectional area of ​​the nozzle outlet end.

[0009] The throat tube has its inlet end connected to the outlet end of the mixing chamber, and the flow cross-sectional area of ​​the throat tube inlet end is smaller than the flow cross-sectional area of ​​the mixing chamber inlet end.

[0010] A diffuser tube is connected at its inlet end to the outlet end of the throat tube, and the flow cross-sectional area at the outlet end of the diffuser tube is larger than the flow cross-sectional area at the inlet end of the diffuser tube.

[0011] The inlet end of the lead-out section is connected to the outlet end of the diffuser tube;

[0012] The air distribution cone is set at the outlet end of the lead-out section, and an annular outlet is formed between the air distribution cone and the inner wall of the outlet end of the lead-out section.

[0013] Preferably, the ratio of the axial distance between the outlet end of the nozzle and the inlet end of the throat to the diameter of the throat is 2-6:1.

[0014] Preferably, the flow cross-sectional area at the inlet end of the throat tube and the flow cross-sectional area at the outlet end of the throat tube are equal, and the ratio of the length of the throat tube to the diameter of the throat tube is 1-6:1.

[0015] Preferably, the expansion angle of the diffuser tube is 2°-4°.

[0016] Preferably, it further includes: an air intake chamber, which is connected to the inlet end of the mixing chamber, and air vents are evenly spaced on the circumferential sidewall of the air intake chamber.

[0017] Preferably, the outlet end of the nozzle is located inside the suction chamber.

[0018] Preferably, the ratio of the inlet diameter of the suction chamber to the outlet diameter of the nozzle is 3-9:1.

[0019] Preferably, the lead-out section is a straight pipe section with a uniform cross-section.

[0020] Preferably, the axes of the nozzle, mixing chamber, throat, diffuser, and air distribution cone all coincide.

[0021] Preferably, the wind-distributing cone is fixed to the outlet end of the lead-out section by at least three support rods.

[0022] As can be seen from the above technical solution, this application provides an injection device for dry desulfurization, the device comprising: a nozzle, the inlet end of which is connected to a high specific surface area calcium hydroxide conveying pipeline, and the flow cross-sectional area of ​​the nozzle is smaller than that of the conveying pipeline; a mixing chamber, the inlet end of which is spaced apart from the outlet end of the nozzle, and the flow cross-sectional area of ​​the inlet end of the mixing chamber is larger than that of the outlet end of the nozzle; a throat, the inlet end of which is connected to the outlet end of the mixing chamber, and the flow cross-sectional area of ​​the inlet end of the throat is smaller than that of the inlet end of the mixing chamber; a diffuser, the inlet end of which is connected to the outlet end of the throat, and the flow cross-sectional area of ​​the outlet end of the diffuser is larger than that of the inlet end of the diffuser; an outlet section, the inlet end of which is connected to the outlet end of the diffuser; and a distribution cone, which is disposed at the outlet end of the outlet section, forming an annular outlet between the distribution cone and the inner wall of the outlet end of the outlet section. This application achieves continuous variation of the flow cross-sectional area through the series connection of the nozzle, mixing chamber, throat, diffuser, outlet section, and distribution cone. The nozzle's flow cross-sectional area is smaller than that of the conveying pipeline; the flow cross-sectional area at the mixing chamber inlet is larger than that at the nozzle outlet; the flow cross-sectional area at the throat inlet is smaller than that at the mixing chamber inlet; and the flow cross-sectional area at the diffuser outlet is larger than that at the diffuser inlet. An annular outlet is formed between the air distribution cone and the inner wall of the outlet section. This multi-stage structure improves the mixing uniformity of high-surface-area calcium hydroxide with flue gas and increases the utilization rate of high-surface-area calcium hydroxide. Attached Figure Description

[0023] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 A three-dimensional structural schematic diagram of the injection device for dry desulfurization provided in the embodiments of this application;

[0025] Figure 2 This is a cross-sectional schematic diagram of an injection device for dry desulfurization provided in an embodiment of this application.

[0026] Illustration:

[0027] The components are: 1. Nozzle; 2. Mixing chamber; 3. Throat; 4. Diffuser; 5. Outlet section; 6. Air distribution cone; 7. Intake chamber. Detailed Implementation

[0028] The embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described below do not represent all embodiments consistent with this application. They are merely examples of systems and methods consistent with some aspects of this application.

[0029] It should be noted that the brief descriptions of terms in this application are only for the convenience of understanding the embodiments described below, and are not intended to limit the embodiments of this application. Unless otherwise stated, these terms should be understood in their ordinary and common meaning.

[0030] The terms “comprising” and “having”, and any variations thereof, are intended to cover but not exclude inclusion, for example, a product or device that includes a range of components is not necessarily limited to all of the components that are clearly listed, but may include other components that are not clearly listed or that are inherent to such product or device.

[0031] In the field of dry desulfurization technology, existing injection devices used to mix high-surface-weight calcium hydroxide with flue gas often suffer from uneven mixing and low desulfurizer utilization. These devices typically use a delivery pipe and nozzles to inject high-surface-weight calcium hydroxide into the flue gas duct, achieving gas-solid mixing through jet entrainment. However, due to a lack of effective flow field organization and mixing path planning, the high-surface-weight calcium hydroxide is unevenly distributed in the flue gas, creating areas of excessively high or low concentrations. This results in some high-surface-weight calcium hydroxide failing to fully participate in the reaction and being discharged from the system, leading not only to a persistently high calcium-to-sulfur ratio but also increasing the amount of solid waste generated, thus affecting the economic operation of the desulfurization system.

[0032] To address the aforementioned problems, this application provides an injection device for dry desulfurization, see [link to relevant documentation]. Figure 1 and Figure 2 It includes: nozzle 1, mixing chamber 2, throat 3, diffuser 4, outlet section 5, and air distribution cone 6.

[0033] The inlet end of nozzle 1 is connected to a high specific surface area calcium hydroxide delivery pipeline. The flow cross-sectional area of ​​nozzle 1 is smaller than that of the high specific surface area calcium hydroxide delivery pipeline. The reduction in flow cross-sectional area increases the velocity of the high specific surface area calcium hydroxide flowing through nozzle 1, forming a high-speed, high specific surface area calcium hydroxide jet.

[0034] Before connecting the inlet end of nozzle 1 to the high specific surface area calcium hydroxide delivery pipeline, the axial distance between the outlet end of nozzle 1 and the inlet end of throat 3 can be determined according to the flue gas volume. Since the outlet end of mixing chamber 2 is fixedly connected to the inlet end of throat 3, the distance between the outlet end of nozzle 1 and the inlet end of mixing chamber 2 is determined synchronously with the axial distance between the outlet end of nozzle 1 and the inlet end of throat 3: when the flue gas volume to be treated is large, the axial distance between the outlet end of nozzle 1 and the inlet end of throat 3 is set to be small, the high-speed high specific surface area calcium hydroxide jet is closer to the inlet of mixing chamber 2, the negative pressure intensity in the inlet area of ​​mixing chamber 2 increases, the induced flue gas volume increases, and sufficient mixing is ensured under large flue gas volume; when the flue gas volume to be treated is small, the axial distance between the outlet end of nozzle 1 and the inlet end of throat 3 is set to be large, the distance between the high-speed high specific surface area calcium hydroxide jet and the inlet of mixing chamber 2 increases, the negative pressure intensity in the inlet area of ​​mixing chamber 2 decreases, the induced flue gas volume decreases accordingly, and excessive flue gas leads to an imbalance in mixing concentration.

[0035] Mixing chamber 2 is located downstream of nozzle 1. The inlet end of mixing chamber 2 is spaced apart from the outlet end of nozzle 1. The flow cross-sectional area at the inlet end of mixing chamber 2 is larger than that at the outlet end of nozzle 1. When the high-speed, high-surface-weight calcium hydroxide jet ejected from the outlet of nozzle 1 enters mixing chamber 2, due to fluid viscosity, the high-speed, high-surface-weight calcium hydroxide jet violently entrains the surrounding flue gas. This entrainment effect carries away a large amount of flue gas from the inlet area of ​​mixing chamber 2, creating a local negative pressure. Under this negative pressure, the surrounding flue gas is continuously drawn into the interior of mixing chamber 2.

[0036] The structure of the mixing chamber 2, with a flow cross-sectional area at the inlet greater than that at the outlet of nozzle 1, provides the necessary space for the full diffusion of the high-speed, high-surface-weight calcium hydroxide jet. When the high-speed, high-surface-weight calcium hydroxide jet enters the mixing chamber 2 from nozzle 1, the increased flow cross-sectional area allows the jet to expand sufficiently, increasing the contact area between the high-surface-weight calcium hydroxide and the flue gas, and promoting the mixing process. The mixing chamber 2 also stabilizes the flow field, ensuring that the gas-solid two-phase flow formed by the initially mixed high-surface-weight calcium hydroxide and flue gas can smoothly enter the downstream throat 3.

[0037] The throat 3 is connected to the outlet end of the mixing chamber 2. The flow cross-sectional area at the inlet end of the throat 3 is smaller than that at the inlet end of the mixing chamber 2. When the gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas enters the throat 3 from the mixing chamber 2, the flow velocity of the gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas is further increased due to the reduced flow cross-sectional area. The high-speed flow state in the throat 3 enhances the turbulence intensity, expands the reaction contact area, and prolongs the reaction contact time, making the contact between high specific surface area calcium hydroxide and flue gas more sufficient. After enhanced mixing, the gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas flows smoothly out from the outlet end of the throat 3 and enters the downstream diffuser 4.

[0038] The inlet end of diffuser 4 connects to the outlet end of throat 3. The flow cross-sectional area at the outlet end of diffuser 4 is larger than that at the inlet end. The gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas enters the inlet end of diffuser 4 from the outlet end of throat 3. The larger flow cross-sectional area at the outlet end of diffuser 4 causes the flow velocity of the gas-solid two-phase flow to gradually decrease as it flows inside diffuser 4. The reduced flow velocity prolongs the residence time of the gas-solid two-phase flow within diffuser 4, allowing for more thorough contact and mixing between the high specific surface area calcium hydroxide and flue gas.

[0039] The inlet end of the outlet section 5 connects to the outlet end of the diffuser pipe 4. A wind-distributing cone 6 is positioned at the outlet end of the outlet section 5. An annular outlet is formed between the wind-distributing cone 6 and the inner wall of the outlet end of the outlet section 5. The conical structure of the wind-distributing cone 6 is located at the center of the flow channel. The gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas is shaped into a hollow conical gas curtain as it passes through the annular outlet. This hollow conical gas curtain expands the mixing interface, allowing it to fully contact the untreated flue gas in the flue where the device is located, promoting the mixing of unreacted high specific surface area calcium hydroxide with the untreated flue gas, and improving the utilization rate of the unreacted high specific surface area calcium hydroxide.

[0040] The mixing chamber 2 is fixed to the inner wall of the flue by at least two symmetrically arranged supports. One end of the support is welded to the outer wall of the mixing chamber 2, and the other end is fixed to the inner wall of the flue by bolts, ensuring that the mixing chamber 2 is stable in position within the flue and does not shift due to airflow impact. The inlet end of the nozzle 1 is connected to a high specific surface area calcium hydroxide conveying pipe. The high specific surface area calcium hydroxide conveying pipe itself has a fixed installation structure, which can ensure the stability of the nozzle 1's installation position within the flue. Combined with the support fixing of the mixing chamber 2, it maintains a stable distance between the outlet end of the nozzle 1 and the inlet end of the mixing chamber 2, avoiding changes in the distance due to displacement of a single component. The outlet section 5 is fixed to the inner wall of the flue by at least two symmetrically arranged supports. One end of the support is welded to the outer wall of the outlet section 5, and the other end is fixed to the inner wall of the flue by bolts, ensuring the stability of the outlet section 5 in position within the flue. By fixing the mixing chamber 2 and the outlet section 5 with the bracket, the installation positions of the mixing chamber 2 and the throat pipe 3, as well as the installation positions of the outlet section 5, the diffuser pipe 4, and the air distribution cone 6, can be maintained simultaneously, avoiding the disruption of the gas-solid two-phase flow path due to component displacement, which would affect the mixing effect of high specific surface area calcium hydroxide and flue gas.

[0041] It should be noted that during actual operation, high specific surface area calcium hydroxide enters nozzle 1 through the delivery pipe. As the high specific surface area calcium hydroxide flows through nozzle 1, its velocity increases, forming a high-speed high specific surface area calcium hydroxide jet. This high-speed high specific surface area calcium hydroxide jet exits nozzle 1 and enters mixing chamber 2. The high-speed high specific surface area calcium hydroxide jet entrains the surrounding flue gas, which is then drawn into the interior of mixing chamber 2. The high-speed high specific surface area calcium hydroxide jet and the flue gas come into contact within the space of mixing chamber 2, completing the initial mixing process. The gas-solid two-phase flow formed by the initially mixed high specific surface area calcium hydroxide and flue gas enters throat 3 from the outlet end of mixing chamber 2. The velocity of this gas-solid two-phase flow increases. The high-speed flow within throat 3 enhances the turbulence intensity, resulting in more thorough contact between the high specific surface area calcium hydroxide and the flue gas. The gas-solid two-phase flow formed by the high specific surface area calcium hydroxide and flue gas enters diffuser 4 from the outlet end of throat 3. The expansion structure of diffuser 4 reduces the velocity of the gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas, and the flow field tends to stabilize. The gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas enters the outlet section 5 from the outlet end of diffuser 4, and is smoothly transported to the area of ​​the air distribution cone 6 at the outlet end through the outlet section 5. A hollow conical air curtain is formed through the annular outlet between the air distribution cone 6 and the inner wall of the outlet end of the outlet section 5. This hollow conical air curtain can fully contact the untreated flue gas in the flue where the device is located. The hollow conical air curtain promotes the mixing of unreacted high specific surface area calcium hydroxide and untreated flue gas.

[0042] As can be seen from the above technical solution, the injection device for dry desulfurization provided in this application achieves efficient mixing of high specific surface area calcium hydroxide and flue gas through a multi-stage structural design. Nozzle 1 accelerates the high specific surface area calcium hydroxide into a high-speed, high specific surface area calcium hydroxide jet through changes in its flow cross-sectional area. Mixing chamber 2 automatically draws in surrounding flue gas using the entrainment effect of the high specific surface area calcium hydroxide jet, allowing the high specific surface area calcium hydroxide jet and flue gas to complete preliminary mixing within the mixing chamber 2. Throat 3 enhances the turbulence intensity of the gas-solid two-phase flow formed by the high specific surface area calcium hydroxide and flue gas through changes in its flow cross-sectional area, making the mixing of high specific surface area calcium hydroxide and flue gas more thorough. Diffuser 4 stabilizes the flow field of the gas-solid two-phase flow formed by the high specific surface area calcium hydroxide and flue gas through its expansion structure, improving the uniformity of the distribution of high specific surface area calcium hydroxide in the flue gas. The outlet end of diffuser 4 is connected to the inlet end of lead-out section 5, and the air distribution cone 6 is located at the outlet end of lead-out section 5. The hollow conical air curtain formed by the high specific surface area calcium hydroxide and flue gas in the air distribution cone 6 promotes the mixing of unreacted high specific surface area calcium hydroxide with untreated flue gas. This multi-stage sequentially connected structure ensures stable flow and thorough mixing of the gas-solid two-phase flow formed by the high specific surface area calcium hydroxide and flue gas, significantly improving the utilization rate of high specific surface area calcium hydroxide, effectively reducing the calcium-sulfur ratio of the desulfurization system, and reducing the amount of solid waste generated.

[0043] In some embodiments, see Figure 1 and Figure 2The ratio of the axial distance between the outlet end of nozzle 1 and the inlet end of throat 3 to the diameter of throat 3 is 2-6:1.

[0044] When the ratio of the axial distance between the outlet end of nozzle 1 and the inlet end of throat 3 to the diameter of throat 3 is less than 2, the high-speed, high-specific-surface-weight calcium hydroxide jet quickly enters the inlet of throat 3 after exiting nozzle 1, resulting in insufficient mixing time between the high-speed, high-specific-surface-weight calcium hydroxide jet and the flue gas. When the ratio of the axial distance between the outlet end of nozzle 1 and the inlet end of throat 3 to the diameter of throat 3 is greater than 6, the high-speed, high-specific-surface-weight calcium hydroxide jet travels a longer distance before entering the inlet of throat 3 after exiting nozzle 1, resulting in greater kinetic energy loss.

[0045] This embodiment optimizes the mixing process of high specific surface area calcium hydroxide with flue gas by setting the ratio of the axial distance between the outlet end of nozzle 1 and the inlet end of throat 3 to the diameter of throat 3 to 2-6:1, thereby improving the utilization efficiency of high specific surface area calcium hydroxide. This ratio range avoids insufficient mixing due to insufficient mixing distance, while also avoiding kinetic energy loss due to excessive mixing distance. It ensures that after the high-speed, high specific surface area calcium hydroxide jet fully entrains the flue gas in the area near the inlet end of mixing chamber 2, it can carry the flue gas into mixing chamber 2 with appropriate kinetic energy to complete the initial mixing. When the gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas enters throat 3 from mixing chamber 2, the turbulence intensity of the gas-solid two-phase flow is enhanced because the flow cross-sectional area at the inlet end of throat 3 is smaller than that at the inlet end of mixing chamber 2. This allows for efficient mixing of the gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas within throat 3, ultimately ensuring that the gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas maintains good mixing uniformity after entering diffuser 4.

[0046] In some embodiments, see Figure 1 and Figure 2 The flow cross-sectional area at the inlet end of the throat tube 3 is equal to the flow cross-sectional area at the outlet end of the throat tube 3, and the ratio of the length of the throat tube 3 to the diameter of the throat tube 3 is 1-6:1.

[0047] The gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas enters the inlet of throat 3 from the outlet of mixing chamber 2. The design that the flow cross-sectional area at the inlet of throat 3 is equal to that at the outlet maintains this flow stability. The ratio of the length to the diameter of throat 3 is 1-6:1, which ensures that the gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas obtains sufficient mixing time inside throat 3, while avoiding pressure loss caused by excessive flow channel length. This allows the gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas to achieve effective mixing in throat 3, and finally flows smoothly out from the outlet of throat 3 into the downstream diffuser 4.

[0048] In some embodiments, see Figure 1 and Figure 2 The expansion angle of diffuser 4 is 2°-4°. The design of the expansion angle of diffuser 4 as 2°-4° makes diffuser 4 form a gradually expanding flow channel.

[0049] In actual operation, the gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas enters the inlet of diffuser 4 at a relatively high velocity from the outlet of throat 3. This flow continues forward within the gradually expanding channel of diffuser 4. The expansion angle of diffuser 4 is 2°-4°, allowing the high-velocity gas-solid two-phase flow to smoothly decelerate. This velocity reduction process converts the kinetic energy of the gas-solid two-phase flow into pressure energy. The reduced-velocity flow then smoothly exits from the outlet of diffuser 4 and enters the distribution cone 6 region.

[0050] This embodiment employs a diffuser 4 with an expansion angle of 2°-4° to achieve a smooth deceleration of the gas-solid two-phase flow formed by the high-velocity, high-surface-area calcium hydroxide flowing out of the throat 3 and the flue gas. The 2°-4° expansion angle of the diffuser 4 ensures a smooth velocity reduction process, improves energy conversion efficiency, enhances flow field stability, and improves the mixing effect between the high-surface-area calcium hydroxide and the flue gas.

[0051] In some embodiments, see Figure 1 and Figure 2 The injection device also includes an intake chamber 7 connected to the inlet end of the mixing chamber 2. The intake chamber 7 is an annular cavity structure surrounding the inlet end of the mixing chamber 2. Ventilation holes are evenly spaced along the circumferential direction on the circumferential sidewall of the intake chamber 7, forming multiple flue gas inlets, allowing flue gas to enter the injection device evenly from all directions. The outlet end of the nozzle 1 is spaced apart from the inlet end of the mixing chamber 2, and the outlet end of the nozzle 1 is located inside the intake chamber 7.

[0052] Understandably, during actual operation, high-surface-weight calcium hydroxide enters nozzle 1 through a delivery pipe, where it is accelerated to form a high-speed, high-surface-weight calcium hydroxide jet. After exiting nozzle 1, the high-speed, high-surface-weight calcium hydroxide jet enters the area near the inlet of mixing chamber 2. Due to fluid viscosity, an entrainment effect occurs, creating a local negative pressure. This negative pressure draws in flue gas evenly through the vents on the circumferential sidewall of suction chamber 7, allowing the flue gas to flow smoothly into mixing chamber 2 from all directions. The flue gas entering mixing chamber 2 comes into contact with the high-speed, high-surface-weight calcium hydroxide jet within the mixing chamber 2, initiating a preliminary mixing process and forming a gas-solid two-phase flow.

[0053] In this embodiment, an intake chamber 7 with uniformly spaced vents is provided to assist the mixing chamber 2 in achieving uniform smoke intake. The annular cavity structure and uniformly distributed vents of the intake chamber 7 improve the uniformity of smoke entry, avoid local smoke concentration deviations caused by single air intake, create favorable conditions for the full mixing of high specific surface area calcium hydroxide and smoke in the mixing chamber 2, and improve the mixing effect of high specific surface area calcium hydroxide and smoke.

[0054] In some embodiments, see Figure 1 and Figure 2 The ratio of the inlet diameter of the suction chamber 7 to the outlet diameter of the nozzle 1 is 3-9:1.

[0055] As can be seen from the above technical solutions, the injection device for dry desulfurization provided in this application optimizes the flue gas intake effect by limiting the ratio of the inlet diameter of the intake chamber 7 to the outlet diameter of the nozzle 1 to 3-9:1. This ratio range ensures that a stable negative pressure zone can be formed in the inlet area of ​​the mixing chamber 2, allowing for the intake of sufficient flue gas with a matching flow rate, and avoiding uneven mixing caused by insufficient or excessive flue gas volume. The ratio of the inlet diameter of the intake chamber 7 to the outlet diameter of the nozzle 1 to 3-9:1 allows high specific surface area calcium hydroxide to fully contact with the flue gas in the initial mixing stage, reducing the phenomenon of excessively high or low local concentrations, providing a good foundation for the subsequent mixing process in the throat 3, and thus improving the utilization rate of high specific surface area calcium hydroxide.

[0056] In some embodiments, see Figure 1 and Figure 2 The lead-out section 5 is a straight pipe section with a constant cross-section. The constant cross-section straight pipe section structure of the lead-out section 5 can provide a stable flow field transition zone for the gas-solid two-phase flow formed by the high specific surface area calcium hydroxide flowing out from the diffuser 4 and the flue gas.

[0057] This embodiment utilizes a straight pipe section with a uniform cross-section in the outlet section 5 to ensure a uniform annular outlet is formed between the air distribution cone 6 and the inner wall of the outlet end of the outlet section 5. The straight pipe section with a uniform cross-section in the outlet section 5 optimizes the flow state of the gas-solid two-phase flow formed by high-surface-weight calcium hydroxide and flue gas before final diffusion, ensuring a uniform and stable flow field. This, in turn, guarantees the symmetry and stability of the hollow conical air curtain formed by the air distribution cone 6, improving the secondary mixing effect between the gas-solid two-phase flow formed by high-surface-weight calcium hydroxide and flue gas and the untreated flue gas.

[0058] In some embodiments, see Figure 1 and Figure 2The axes of nozzle 1, mixing chamber 2, throat 3, diffuser 4, and air distribution cone 6 are kept coaxial. The coincidence of the axes of nozzle 1, mixing chamber 2, throat 3, diffuser 4, and air distribution cone 6 ensures that the gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas maintains a stable flow trajectory throughout the device, avoiding uneven flow and energy loss caused by misalignment.

[0059] This embodiment establishes a continuous axisymmetric flow channel by maintaining the coincidence of the axes of nozzle 1, mixing chamber 2, throat 3, diffuser 4, and air distribution cone 6. The coincidence of the axes of nozzle 1, mixing chamber 2, throat 3, diffuser 4, and air distribution cone 6 ensures a smooth transition of the gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas among the various components of nozzle 1, mixing chamber 2, throat 3, diffuser 4, and air distribution cone 6, improving the mixing uniformity of high specific surface area calcium hydroxide and flue gas, and ensuring the symmetrical distribution of the hollow conical air curtain.

[0060] In some embodiments, see Figure 1 The air distribution cone 6 is located at the outlet end of the lead-out section 5 and is fixed to the outlet end of the lead-out section 5 by at least three support rods. In this embodiment, three support rods are used, but four or more support rods can also be set according to actual working conditions. All support rods are evenly distributed along the circumference of the air distribution cone 6. One end of each support rod is welded to the outer wall of the air distribution cone 6, and the other end of each support rod is welded to the inner wall of the outlet end of the lead-out section 5.

[0061] In this embodiment, after the air distribution cone 6 is fixed to the outlet end of the lead-out section 5 by three support rods, the air distribution cone 6 remains stable at the center position of the outlet end of the lead-out section 5 and will not shift due to the impact of the gas-solid two-phase flow. If four or more support rods are used, the four or more support rods are also evenly distributed along the circumference of the air distribution cone 6. One end of each support rod is welded to the outer wall of the air distribution cone 6, and the other end of each support rod is welded to the inner wall of the outlet end of the lead-out section 5. This also ensures that the air distribution cone 6 remains stable at the center position of the outlet end of the lead-out section 5. The structure of the air distribution cone 6 being fixed to the outlet end of the lead-out section 5 by support rods can ensure that the gas-solid two-phase flow formed by high specific surface area calcium hydroxide and flue gas flows out evenly from the annular outlet between the air distribution cone 6 and the inner wall of the outlet end of the lead-out section 5. This allows the hollow cone-shaped air curtain formed by the gas-solid two-phase flow of high specific surface area calcium hydroxide and flue gas to fully contact the untreated flue gas in the flue where the injection device is located, thereby maintaining a stable mixing effect between high specific surface area calcium hydroxide and flue gas.

[0062] Similar parts between the embodiments provided in this application can be referred to mutually. The specific implementation methods provided above are only a few examples under the overall concept of this application and do not constitute a limitation on the scope of protection of this application. For those skilled in the art, any other implementation methods extended from the solution of this application without creative effort shall fall within the scope of protection of this application.

Claims

1. A spraying device for dry desulfurization, characterized in that, include: Nozzle (1), the inlet end of the nozzle (1) is connected to the high specific surface area calcium hydroxide conveying pipeline, and the flow cross-sectional area of ​​the nozzle (1) is smaller than the flow cross-sectional area of ​​the conveying pipeline; A mixing chamber (2) is provided with its inlet end spaced apart from the outlet end of the nozzle (1), and the flow cross-sectional area of ​​the inlet end of the mixing chamber (2) is greater than the flow cross-sectional area of ​​the outlet end of the nozzle (1). The throat (3) has its inlet end connected to the outlet end of the mixing chamber (2), and the flow cross-sectional area of ​​the inlet end of the throat (3) is smaller than the flow cross-sectional area of ​​the inlet end of the mixing chamber (2). A diffuser tube (4) is provided, the inlet end of which is connected to the outlet end of the throat tube (3), and the flow cross-sectional area of ​​the outlet end of the diffuser tube (4) is greater than the flow cross-sectional area of ​​the inlet end of the diffuser tube (4). The lead-out section (5) is connected to the outlet end of the diffuser tube (4); The air distribution cone (6) is located at the outlet end of the lead-out section (5), and an annular outlet is formed between the air distribution cone (6) and the inner wall of the outlet end of the lead-out section (5).

2. The injection device for dry desulfurization according to claim 1, characterized in that, The ratio of the axial distance between the outlet end of the nozzle (1) and the inlet end of the throat (3) to the diameter of the throat (3) is 2-6:

1.

3. The injection device for dry desulfurization according to claim 1, characterized in that, The flow cross-sectional area at the inlet end of the throat (3) is equal to the flow cross-sectional area at the outlet end of the throat (3), and the ratio of the length of the throat (3) to the diameter of the throat (3) is 1-6:

1.

4. The injection device for dry desulfurization according to claim 1, characterized in that, The expansion angle of the diffuser tube (4) is 2°-4°.

5. The injection device for dry desulfurization according to claim 1, characterized in that, Also includes: The air intake chamber (7) is connected to the inlet end of the mixing chamber (2), and the circumferential sidewall of the air intake chamber (7) is provided with air vents at even intervals.

6. The injection device for dry desulfurization according to claim 5, characterized in that, The outlet end of the nozzle (1) is located inside the suction chamber (7).

7. The injection device for dry desulfurization according to claim 5, characterized in that, The ratio of the inlet diameter of the air intake chamber (7) to the outlet diameter of the nozzle (1) is 3-9:

1.

8. The injection device for dry desulfurization according to claim 1, characterized in that, The lead-out section (5) is a straight pipe section with a uniform cross-section.

9. The injection device for dry desulfurization according to claim 1, characterized in that, The axes of the nozzle (1), mixing chamber (2), throat (3), diffuser (4) and air distribution cone (6) are all coincident.

10. The injection device for dry desulfurization according to claim 1, characterized in that, The wind-distributing cone (6) is fixed to the outlet end of the lead-out section (5) by at least three support rods.

Images