Anti-blocking and anti-corrosion air preheater device

Abstract

The utility model discloses an air preheater equipment of anticlogging anticorrosion relates to air preheater technical field, including sodium carbonate storage jar, metering pump, multi -jet -lance and compressed air machine, the outlet of sodium carbonate storage jar is connected with the inlet of metering pump through the pipeline, and the one end export of metering pump is connected with multi -jet -lance through the pipeline, and sodium carbonate solution is atomized after being sprayed into flue gas through double -fluid atomizing nozzle, can be fast with SO3 reaction and generate stable sodium sulfate and so on material, avoid SO3 and ammonia escape and generate the ammonium bisulfate with strong viscosity. Meanwhile, the reaction product has no viscosity and will not adsorb fly ash, reduces the ash deposition of air preheater heat exchange element surface from the source, thoroughly solves the problem that traditional steam blowing and water washing can not clean in time, causes the problem of ash plugging shutdown, in addition, sodium carbonate solution and SO3 in flue gas high -efficient reaction, reduce SO3 concentration in flue gas greatly, thereby reduce the acid dew point temperature.

Description

Technical Field

[0001] This utility model relates to the field of air preheater technology, and in particular to air preheater equipment that is anti-clogging and anti-corrosion. Background Technology

[0002] In the field of coal-fired power generation, air preheaters are key equipment for improving boiler thermal efficiency and optimizing the combustion process. Their main function is to utilize the waste heat from the flue gas at the boiler's tail end to preheat the air entering the boiler, thereby reducing exhaust gas temperature, minimizing heat loss, and enhancing the combustion process. Based on the heat transfer method, air preheaters are mainly divided into indirect heat transfer type (such as tubular type) and regenerative type (such as rotary type), and are widely used in power plant boilers.

[0003] However, with increasingly stringent environmental regulations, coal-fired power plants have widely adopted SCR (Selective Catalytic Reduction) denitrification technology. While this has effectively reduced nitrogen oxide emissions, it has also triggered a series of thorny problems. On the one hand, during the denitrification process, some SO2 is oxidized to SO3, and coupled with ammonia escape, this generates highly viscous ammonium bisulfate. This molten state at 146-207℃ makes it extremely easy to adhere to the surface of the heat exchange elements in the air preheater, causing corrosion and attracting large amounts of fly ash, ultimately leading to ash blockage and severely impacting the safe operation of the equipment. Some power plants have even had to limit load or shut down as a result. On the other hand, the increased SO3 concentration in the flue gas raises the acid dew point temperature. When the exhaust gas temperature is below the acid dew point, the sulfuric acid droplets generated by the condensation of sulfuric acid vapor corrode the cold-end heat exchange elements, especially in the low-temperature region where corrosion is more severe.

[0004] Therefore, this utility model proposes an air preheater device that is anti-clogging and anti-corrosion to solve the above problems. Utility Model Content

[0005] In view of the problems existing in the prior art, this utility model is proposed.

[0006] To solve the above-mentioned technical problems, this utility model provides the following technical solution: an air preheater device with anti-clogging and anti-corrosion properties, which includes a sodium carbonate storage tank, a metering pump, a multi-nozzle spray gun and a compressed air compressor; the outlet of the sodium carbonate storage tank is connected to the inlet of the metering pump through a pipe, and the outlet of the metering pump away from the sodium carbonate storage tank is connected to the multi-nozzle spray gun through a pipe.

[0007] In a preferred embodiment of the anti-clogging and anti-corrosion air preheater equipment of the present invention, a dual filter is connected in series on the pipeline between the metering pump and the multi-nozzle spray gun, the inlet of the dual filter is connected to the outlet of the metering pump, and the outlet of the dual filter is connected to the inlet of the multi-nozzle spray gun.

[0008] As a preferred embodiment of the anti-clogging and anti-corrosion air preheater equipment of the present invention, a softened water supply device for diluting sodium carbonate solution is connected in series on the pipeline between the dual filter and the metering pump.

[0009] As a preferred embodiment of the anti-clogging and anti-corrosion air preheater equipment of the present invention, wherein: a density meter for real-time monitoring of the density of sodium carbonate solution diluted with softened water, a flow meter for measuring the flow rate of the solution flowing through the pipeline, and a flow control valve are sequentially installed on the pipeline located between the metering pump and the multi-nozzle spray gun, and between the softened water supply device and the multi-nozzle spray gun.

[0010] As a preferred embodiment of the anti-clogging and anti-corrosion air preheater equipment of the present invention, the number of dual-fluid atomizing nozzles on the multi-nozzle spray gun is at least two, and each dual-fluid atomizing nozzle is connected to a compressed air machine through an independent pipe.

[0011] In a preferred embodiment of the anti-clogging and anti-corrosion air preheater equipment of the present invention, the bottom end of the sodium carbonate storage tank is provided with a support frame for support, and the sodium carbonate storage tank stores sodium carbonate solution.

[0012] As a preferred embodiment of the anti-clogging and anti-corrosion air preheater equipment of the present invention, the softened water supply device includes a softened water storage tank, an outlet hose and a suction pump. The suction pump is mounted on the softened water storage tank, and the softened water storage tank is connected to the pipeline between the metering pump and the dual filter through the outlet hose.

[0013] As a preferred embodiment of the anti-clogging and anti-corrosion air preheater equipment of the present invention, the multi-nozzle spray gun includes a mounting box and at least two connecting bases configured outside the mounting box. The dual-fluid atomizing nozzle is assembled with the mounting box through the connecting bases, and the end of the dual-fluid atomizing nozzle away from the nozzle is connected to the inner cavity of the mounting box.

[0014] As a preferred embodiment of the anti-clogging and anti-corrosion air preheater equipment of the present invention, the metering pump is configured with an adjustable flow rate structure.

[0015] In a preferred embodiment of the anti-clogging and anti-corrosion air preheater equipment of the present invention, the flow control valve is configured as an electrically adjustable ball valve.

[0016] The beneficial effects of this invention are as follows: This invention uses a dual-fluid atomizing nozzle 152 to atomize sodium carbonate solution and spray it into the flue gas. This allows for rapid reaction with SO3 to generate stable substances such as sodium sulfate, preventing SO3 from escaping with ammonia to form highly viscous ammonium bisulfate. Simultaneously, the reaction products are non-sticky and do not adsorb fly ash, reducing ash accumulation and agglomeration on the surface of the air preheater's heat exchange elements from the source. This completely solves the problem of traditional steam blowing and water washing failing to clean in time, leading to ash blockage and shutdown. Furthermore, the efficient reaction of sodium carbonate solution with SO3 in the flue gas significantly reduces the SO3 concentration, thereby lowering the acid dew point temperature. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the overall structure of the air preheater device in this utility model;

[0019] Figure 2 This utility model Figure 1 Enlarged view of the A-section structure;

[0020] Figure 3 This is a schematic diagram of the overall structure of the multi-nozzle spray gun in this utility model.

[0021] Explanation of reference numerals in the attached drawings: 11. Support frame; 12. Sodium carbonate storage tank; 13. Metering pump; 14. Dual filter; 15. Multi-nozzle spray gun; 151. Mounting carrier; 152. Atomizing dual-fluid atomizing nozzle; 153. Connecting base; 16. Compressed air compressor; 171. Softened water storage tank; 172. Suction pump; 18. Densitometer; 19. Flow meter; 20. Flow control valve. Detailed Implementation

[0022] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0023] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0024] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single embodiment or an embodiment selectively excluded from other embodiments.

[0025] Reference Figures 1-3 As shown, an air preheater device with anti-clogging and anti-corrosion features includes a sodium carbonate storage tank 12, a metering pump 13, a multi-nozzle spray gun 15, and a compressed air compressor 16. The outlet of the sodium carbonate storage tank 12 is connected to the inlet of the metering pump 13 via a pipe, and the outlet of the metering pump 13 away from the sodium carbonate storage tank 12 is connected to the multi-nozzle spray gun 15 via a pipe.

[0026] Furthermore, the bottom of the sodium carbonate storage tank 12 is provided with a support frame 11 for support.

[0027] Furthermore, the sodium carbonate storage tank 12 is used to store a sodium carbonate solution with a concentration of 20% to 25%, providing raw materials for the removal of SO3 and other acidic gases; the metering pump 13 is configured with an adjustable flow rate structure, and the metering pump 13 delivers the sodium carbonate concentrate from the sodium carbonate storage tank 12 to the pipeline between the metering pump 13 and the dual filter 14. The operator can set the flow rate of the metering pump 13 according to the process requirements to achieve a precise supply of sodium carbonate solution.

[0028] In one embodiment, a softened water supply device is connected in series on the pipeline between the dual filter 14 and the metering pump 13. The softened water supply device injects softened water into the pipeline between the dual filter 14 and the multi-nozzle spray gun 15 to dilute the sodium carbonate solution online to the required spray concentration and prevent calcium carbonate scale from forming in the pipeline and nozzle.

[0029] Furthermore, the softened water supply device includes a softened water storage tank 171, an outlet hose, and a suction pump 172. The suction pump 172 is mounted on the softened water storage tank 171, which is connected to the pipeline between the metering pump 13 and the dual filter 14 via the outlet hose.

[0030] In one embodiment, a dual filter 14 is connected in series on the pipeline between the metering pump 13 and the multi-nozzle spray gun 15 and the spray gun. The inlet of the dual filter 14 is connected to the outlet of the metering pump 13, and the outlet of the dual filter 14 is connected to the inlet of the multi-nozzle spray gun 15.

[0031] Furthermore, the dual filter 14 is used to filter the sodium carbonate solution diluted to the required spray concentration in the pipeline, remove impurities, and prevent clogging of the multi-nozzle spray gun 15 and the dual-fluid atomizer.

[0032] In one embodiment, a densitometer 18, a flow meter 19, and a flow control valve 20 are sequentially installed on the pipeline between the metering pump 13 and the multi-nozzle spray gun 15, and between the softened water supply device and the multi-nozzle spray gun 15.

[0033] Furthermore, the anti-clogging and anti-corrosion air preheater is also equipped with a control system electrically connected to the densitometer 18, flow meter 19, and flow control valve 20. The flow control valve 20 is configured as an electrically adjustable ball valve, and the control system has a pre-stored model of the correspondence between solution concentration and density based on experimental data calibration. This model is established by measuring the density values ​​of sodium carbonate solutions of different concentrations at the operating temperature and covers the density parameters within the commonly used injection concentration range.

[0034] Densitometer 18 monitors the density of the sodium carbonate solution diluted with softened water in real time and transmits the monitored density signal to the control system in real time. The control system determines whether the solution concentration meets the injection requirements based on the preset correspondence between solution concentration and density. Flow meter 19 measures the flow rate of the solution flowing through the pipeline and feeds back the flow data to the control system in real time, providing accurate data for flow regulation. Flow control valve 20 receives the regulation command issued by the control system. This command is generated based on the concentration data monitored by densitometer 18, the flow information fed back by flow meter 19, and the injection parameters preset by the process.

[0035] The injection parameters preset in the process need to be pre-set in the control system based on the concentration of SO3 and other acidic gases in the flue gas, the flue gas flow rate, temperature, and other operating conditions. When the solution concentration detected by the densitometer 18 deviates from the preset range, the control system will calculate the required amount of softened water replenishment or sodium carbonate solution adjustment, and adjust the flow control valve 20 and the suction pump 172 to bring the solution concentration back to the preset range, so as to ensure the atomization injection effect and the stability of the reaction with the flue gas.

[0036] Furthermore, the densitometer 18 is used to monitor the density of the sodium carbonate solution diluted with softened water in real time to reflect whether the solution concentration meets the spraying requirements; the flow meter 19 is used to measure the flow rate of the solution flowing through the pipeline, providing data for flow control; the flow control valve 20 is adjusted in real time according to the concentration data monitored by the densitometer 18 and the flow information fed back by the flow meter 19, combined with the spraying parameters set by the process, to ensure that the concentration and flow rate of the sodium carbonate solution entering the multi-nozzle spray gun 15 are stable within the preset range, so as to ensure the stability of atomization spraying and reaction with flue gas.

[0037] In one embodiment, the multi-nozzle spray gun 15 has at least two dual-fluid atomizing nozzles 152, and each dual-fluid atomizing nozzle 152 is connected to a compressed air compressor 16 through an independent pipe. The compressed air compressor 16 provides compressed air to the dual-fluid atomizing nozzles 152 on the multi-nozzle spray gun 15, so that the agent in the multi-nozzle spray gun 15 is atomized, ensuring that the agent and flue gas are fully mixed, improving the reaction efficiency, and effectively removing SO3 and other acidic gases.

[0038] Furthermore, the multi-nozzle spray gun 15 includes a mounting box 151 and at least two connecting bases 153 disposed outside the mounting box 151. The mounting box 151 is assembled with a dual-fluid atomizing nozzle 152 through the connecting bases 153. The end of the dual-fluid atomizing nozzle 152 away from the nozzle opening is connected to the inner cavity of the mounting box 151. The mounting box 151 is assembled at the end of the pipeline away from the dual filter 14.

[0039] During operation, the operator presets injection parameters in the control system based on actual operating conditions such as SO3 concentration in the flue gas, flue gas flow rate, and temperature. These parameters include the target concentration range of sodium carbonate solution, flow rate range, and concentration-density correspondence model, providing a benchmark for subsequent automatic control.

[0040] Subsequently, a sodium carbonate solution with a concentration of 20% to 25% is filled into the sodium carbonate storage tank 12, and the support frame 11 at the bottom provides stable support for the sodium carbonate storage tank 12.

[0041] The air preheater is started, and the metering pump 13 draws sodium carbonate concentrate from the storage tank 12 and delivers it through the pipeline to the pipeline between the metering pump 13 and the dual filter 14. The operator presets the initial flow rate of the metering pump 13 according to the process requirements.

[0042] During the solution transportation process, the softened water supply device is started simultaneously: the softened water in the softened water storage tank 171 is injected into the pipeline between the metering pump 13 and the dual filter 14 through the outlet hose of the suction pump 172 under the action of the suction pump 172, so as to dilute the sodium carbonate concentrate online and preliminarily adjust the solution concentration.

[0043] The diluted sodium carbonate solution enters a dual filter 14, which removes impurities before flowing through a pipeline to a multi-nozzle spray gun 15. Before reaching the multi-nozzle spray gun 15, the solution passes sequentially through a densitometer 18, a flow meter 19, and a flow control valve 20. The densitometer 18 monitors the solution density in real time and transmits the signal to the control system. The control system then uses a pre-stored concentration-density correlation model to determine whether the solution concentration meets the preset requirements. The flow meter 19 measures the flow rate and feeds back the data to the control system, providing real-time data for adjustment.

[0044] The control system combines preset parameters with real-time monitoring data to send regulation commands to the flow control valve 20. At the same time, it adjusts the operating frequency of the suction pump 172 to precisely control the amount of softened water injected, ensuring that the solution concentration and flow rate remain stable within the preset range.

[0045] Finally, the qualified sodium carbonate solution enters the mounting box 151 of the multi-nozzle spray gun 15 and is distributed to each atomizing dual-fluid atomizing nozzle 152. At this time, the compressed air compressor 16 supplies compressed air to each atomizing dual-fluid atomizing nozzle 152 through independent pipelines, so that the sodium carbonate solution is atomized and sprayed into the flue gas. The atomized sodium carbonate solution reacts fully with SO3 and other acidic gases in the flue gas, completing the removal process.

[0046] This air preheater equipment atomizes sodium carbonate solution and injects it into the flue gas through atomizing dual-fluid atomizing nozzle 152. This solution reacts rapidly with SO3 to generate stable sodium sulfate and other substances, preventing SO3 from escaping with ammonia to form highly viscous ammonium bisulfate. Simultaneously, the reaction products are non-sticky and do not adsorb fly ash, reducing ash accumulation and agglomeration on the surface of the air preheater's heat exchange elements from the source. This completely solves the problem of ash blockage and shutdown caused by the inability of traditional steam blowing and water flushing to clean in a timely manner. Furthermore, the efficient reaction of sodium carbonate solution with SO3 in the flue gas significantly reduces the SO3 concentration, thereby lowering the acid dew point temperature. Even at low exhaust temperatures, it reduces sulfuric acid vapor condensation, effectively mitigating corrosion of the cold-end heat exchange elements of the air preheater, especially improving corrosion in the low-temperature region.

[0047] This air preheater equipment, through the coordinated action of the control system, densitometer 18, flow meter 19, and flow control valve 20, achieves precise control of solution concentration and flow rate, ensuring a stable reaction rate and achieving an ideal SO3 removal rate. Compared to traditional steam soot blowing, it eliminates the need for large amounts of steam, reducing energy consumption and avoiding adverse effects on downstream equipment, thus minimizing equipment maintenance costs and downtime losses.

[0048] The dual filter 14 in this air preheater removes impurities from the solution and prevents clogging of the multi-nozzle spray gun 15 and the atomizing dual-fluid atomizing nozzle 152; the softened water supply device avoids calcium carbonate scaling in the pipelines and nozzles, extends the service life of the equipment, and reduces downtime caused by clogging and scaling.

[0049] Finally, the following points should be noted: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection", and "linkage" should be interpreted broadly, and can be mechanical or electrical connections, or internal connections between two components, or direct connections. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may change.

[0050] Secondly: The accompanying drawings of the embodiments disclosed in this utility model only involve the structures involved in the embodiments disclosed in this utility model. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this utility model can be combined with each other.

[0051] Finally: The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An air preheater device that is resistant to clogging and corrosion, characterized in that: It includes a sodium carbonate storage tank (12), a metering pump (13), a multi-nozzle spray gun (15), and a compressed air machine (16); the outlet of the sodium carbonate storage tank (12) is connected to the inlet of the metering pump (13) through a pipe, and the outlet of the metering pump (13) away from the sodium carbonate storage tank (12) is connected to the multi-nozzle spray gun (15) through a pipe.

2. The anti-clogging and anti-corrosion air preheater equipment as described in claim 1, characterized in that: A dual filter (14) is connected in series on the pipeline between the metering pump (13) and the multi-nozzle spray gun (15). The inlet of the dual filter (14) is connected to the outlet of the metering pump (13), and the outlet of the dual filter (14) is connected to the inlet of the multi-nozzle spray gun (15).

3. The anti-clogging and anti-corrosion air preheater equipment according to claim 2, characterized in that: A softened water supply device for diluting the sodium carbonate solution is connected in series on the pipeline between the dual filter (14) and the metering pump (13).

4. The anti-clogging and anti-corrosion air preheater equipment as described in claim 3, characterized in that: A density meter (18) for real-time monitoring of the density of sodium carbonate solution diluted with softened water, a flow meter (19) for measuring the flow rate of the solution flowing through the pipeline, and a flow control valve (20) are installed sequentially on the pipeline between the metering pump (13) and the multi-nozzle spray gun (15), the softened water supply device and the multi-nozzle spray gun (15).

5. The anti-clogging and anti-corrosion air preheater equipment as described in claim 1, characterized in that: The multi-nozzle spray gun (15) has at least two dual-fluid atomizing nozzles (152), and each dual-fluid atomizing nozzle (152) is connected to a compressed air machine (16) through an independent pipe.

6. The anti-clogging and anti-corrosion air preheater equipment as described in claim 1, characterized in that: The sodium carbonate storage tank (12) is provided with a support frame (11) at the bottom for support, and the sodium carbonate storage tank (12) stores sodium carbonate solution.

7. The anti-clogging and anti-corrosion air preheater equipment as described in claim 3, characterized in that: The softened water supply device includes a softened water storage tank (171), an outlet hose and a suction pump (172). The suction pump (172) is mounted on the softened water storage tank (171). The softened water storage tank (171) is connected to the pipeline between the metering pump (13) and the dual filter (14) through the outlet hose.

8. The anti-clogging and anti-corrosion air preheater equipment as described in claim 5, characterized in that: The multi-nozzle spray gun (15) includes a mounting box (151) and at least two connecting bases (153) disposed outside the mounting box (151). The dual-fluid atomizing nozzle (152) is assembled with the mounting box (151) through the connecting bases (153), and the end of the dual-fluid atomizing nozzle (152) away from the nozzle is connected to the inner cavity of the mounting box (151).

9. The anti-clogging and anti-corrosion air preheater equipment as described in claim 1, characterized in that: The metering pump (13) is configured with an adjustable flow rate.

10. The anti-clogging and anti-corrosion air preheater equipment as described in claim 4, characterized in that: The flow control valve (20) is configured as an electrically adjustable ball valve.

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