Waste incinerator in-furnace desulfurization system

Abstract

This utility model relates to the field of waste incineration power generation and discloses an in-furnace desulfurization system for a waste incinerator. It includes an injector installed inside the furnace, a conveying pipe connected to the injector and a Roots blower, and a desulfurizing agent tank connected to the conveying pipe. A blower outlet valve and a pressure gauge are sequentially installed on the conveying pipe. The system also includes an air compressor, a compressed air storage tank, a main air pipe, several purge pipes, and purge valves. The air compressor, compressed air storage tank, and main air pipe are connected sequentially. Several purge pipes are connected to the main air pipe via branch pipes, and each purge pipe is equipped with a purge valve. The purge pipes are located on the horizontal section and bends of the conveying pipe between the blower outlet valve and the injector. This utility model utilizes high-pressure air to purge and clean the conveying pipe, solving the problem of increased pipe resistance due to small particles adhering to the pipe, thereby effectively reducing the likelihood of injector blockage and eliminating the need for frequent disassembly and cleaning of the injector.

Description

Technical Field

[0001] This utility model relates to the field of waste incineration power generation, and in particular to an in-furnace desulfurization system for waste incinerators. Background Technology

[0002] The in-furnace desulfurization system of a waste incinerator is one of the important pieces of equipment in the flue gas purification system of a waste-to-energy plant. Its structure is shown in the attached figure. Figure 3 As shown, it mainly uses a pneumatic conveying device to spray limestone powder of about 200 mesh into the optimal temperature zone inside the furnace using high-pressure fluidized air, so that the limestone has good contact and reaction time with the flue gas. The limestone decomposes into calcium oxide and carbon dioxide when heated, and then reacts with sulfur dioxide in the flue gas to produce calcium sulfite and calcium sulfate, which are eventually oxidized into calcium sulfate.

[0003] As the operating cycle of the ejector increases, many small particles accumulate on the conveying pipeline (especially horizontal pipelines and bends), leading to increased pipeline resistance. When the pipeline resistance reaches a certain level and triggers an alarm, backflow will occur at the pipeline inlet, resulting in exceeding environmental standards, increased lime slurry usage, and increased fly ash production. High pipeline resistance also easily causes ejector blockage, requiring switching to a backup ejector. The blocked ejector then needs to be removed and soaked in citric acid for a period until it is clean. However, the furnace temperature is high at the ejector's installation location, increasing the risk of burns from high-temperature flue gas during disassembly and reassembly.

[0004] Based on this, this application provides an in-furnace desulfurization system for a waste incinerator to solve the above problems. Summary of the Invention

[0005] This invention aims to solve the technical problems existing in the prior art. To this end, this invention provides an in-furnace desulfurization system for waste incinerators, which utilizes high-pressure air to purge and clean the conveying pipeline, thereby solving the problem that the pipeline resistance increases due to the adhesion of many small particles, making the injectors prone to clogging.

[0006] The technical solution adopted by this utility model to solve its technical problem is: A waste incinerator desulfurization system is provided, comprising an injector installed in the furnace of the waste incinerator, a conveying pipeline connected to the injector and a Roots blower, and a desulfurizing agent tank connected to the conveying pipeline. A blower outlet valve and a pressure gauge are sequentially installed on the conveying pipeline. The system also includes an air compressor, a compressed air storage tank, a main air pipe, several purge pipes, and purge valves. The air compressor, compressed air storage tank, and main air pipe are sequentially connected. Several purge pipes are connected to the main air pipe through branch pipes. Each purge pipe is equipped with a purge valve. Several purge pipes are located on the horizontal section and bends of the conveying pipeline between the blower outlet valve and the injector.

[0007] In some alternative embodiments, the purge pipes are inclined and evenly spaced on the horizontal section of the conveying pipe, with the inclination direction facing the conveying direction and the inclination angle not exceeding 45°; the purge pipes are located on the arc-shaped part outside the bend.

[0008] In some alternative embodiments, the purge pipe is also provided on a vertical section of the conveying pipe located at the outlet valve of the blower and the ejector, inclined in the direction of conveying, with an inclination angle not greater than 45°.

[0009] In some alternative embodiments, the spacing between purge pipes on the vertical section of the delivery pipeline is greater than the spacing between purge pipes on the horizontal section.

[0010] In some alternative embodiments, the main air pipe is provided with a purge master valve.

[0011] In some alternative embodiments, the conveying pipe is located at the front end of the injector and is also connected to an air jet mill via a bypass pipe. The outlet of the air jet mill is connected to the conveying pipe, and its inlet is connected to the main air pipe. An air inlet valve is provided on the air inlet. A first switching valve is provided on the conveying pipe behind the bypass pipe, and a second switching valve is provided on the bypass pipe.

[0012] In some alternative embodiments, the air jet mill is a flat air jet mill.

[0013] Compared with the prior art, the beneficial effects of this utility model are: 1. This utility model can use high-pressure air to purge and clean the conveying pipeline, which can solve the problem of increased pipeline resistance caused by small particles adhering to the pipeline, thereby effectively reducing the probability of blockage of the ejector and eliminating the need for frequent disassembly of the ejector for cleaning. 2. The bypass pipe and air jet pulverizer installed on the conveying pipeline can pulverize the particles cleaned from the conveying pipeline, preventing the ejector from being blocked by potentially large particles. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in 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, wherein: Figure 1 This is a schematic diagram of the in-furnace desulfurization system of the waste incinerator provided in Example 1; Figure 2 This is a schematic diagram of the in-furnace desulfurization system of the waste incinerator provided in Example 2; Figure 3 This is a schematic diagram of the existing in-furnace desulfurization system for waste incinerators.

[0015] The attached diagram lists the components represented by each number as follows: 1—Roots blower, 2—Transportation pipeline, 3—Desulfurizing agent silo, 4—Ejector, 5—Air compressor, 6—Compressed air storage tank, 7—Main air pipe, 8—Several purge pipes, 9—Purge valve, 10—Waste incinerator, 11—Blower outlet valve, 12—Pressure gauge, 13—Main purge valve, 14—Bypass pipe, 15—Air jet pulverizer, 16—Ventilation valve, 17—First switching valve, 18—Second switching valve. Detailed Implementation

[0016] It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0018] In the description of this utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," etc., used in this utility model are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. The terms "installed," "connected," and "joined" should be interpreted broadly; for example, they may refer to a fixed connection, a detachable connection, or an integral connection; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; and they may refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0019] Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model. Example

[0020] As attached Figure 1 As shown, this embodiment provides an in-furnace desulfurization system for a waste incinerator, including a Roots blower 1, a conveying pipeline 2, a desulfurizing agent storage tank 3, an injector 4, an air compressor 5, a compressed air storage tank 6, a main air pipe 7, several purge pipes 8, and purge valves 9, wherein: The Roots blower 1 is connected to the injector 4 located in the furnace of the waste incinerator 10 via the conveying pipe 2. Both the Roots blower and the injector are designed with one in reserve and one in use. The desulfurizing agent silo 3 is filled with limestone powder, and its bottom outlet is connected to the conveying pipe 2. The conveying pipe 2 is equipped with a blower outlet valve 11 and a pressure gauge 12. The blower outlet valve serves as the pneumatic conveying switch of the system, and the pressure gauge is used to detect the pipe pressure in the conveying pipe.

[0021] The air compressor 5, compressed air tank 6, and main air pipe 7 are connected in sequence. Several purge pipes 8 are connected to the main air pipe 7 via branch pipes, and each purge pipe 8 is equipped with a purge valve 9. Since blockages easily form in the horizontal sections and bends of the conveying pipeline, in this embodiment, several purge pipes 8 are installed on the horizontal section and bends of the conveying pipeline 2 between the blower outlet valve 11 and the ejector 4. Specifically, the purge pipes 8 are installed at equal intervals and at an angle on the horizontal section of the conveying pipeline 2, with the angle of inclination facing the conveying direction and not exceeding 45°. The distance between two adjacent purge pipes 8 can be 1-2 meters, depending on the actual situation. The purge pipes 8 are located on the arc-shaped portion outside the bend.

[0022] In one embodiment, a purge pipe 8 can also be installed in the vertical section of the conveying pipe 2. Specifically, the purge pipe 8 is installed obliquely on the vertical section of the conveying pipe 2 located between the blower outlet valve 11 and the ejector 4, with the oblique direction facing the conveying direction and the oblique angle not exceeding 45°. Since the vertical section is less prone to blockage, the spacing between the purge pipes 8 on the vertical section of the conveying pipe 2 is greater than the spacing between the purge pipes 8 on the horizontal section.

[0023] Preferably, the main air pipe 7 in this embodiment is provided with a purge valve 13, which serves as the main control valve for compressed air.

[0024] In practice, the delivery pipeline can be purged and cleaned periodically (e.g., every 4 hours) to prevent large particles from clogging the injector. However, when the pressure gauge reading rises to the set value, the following operation must be performed: Close the discharge valve of the desulfurizing agent silo, keep the Roots blower running, start the air compressor, and open the main purge valve. Starting from the blower outlet valve, open the purge valves sequentially to perform high-pressure cleaning of the conveying pipeline until the pressure gauge reading drops to the set value. Then, close the purge valves and the main purge valve sequentially, while slowly opening the discharge valve of the desulfurizing agent silo. During this period, the amount of semi-dry lime slurry in the deacidification reaction tower can be appropriately increased to control the emission of acidic gases in the flue gas and maintain it at a stable emission concentration. After the conveying pipeline is purged, reduce the amount of semi-dry lime slurry. Example

[0025] Based on Example 1, as shown in the appendix Figure 2 As shown, in this embodiment, an air jet mill 15 is further connected to the front end of the conveying pipe 2 at the injector 4 via a bypass pipe 14. In this embodiment, the air jet mill 15 is preferably a flat air jet mill. The feed port of the air jet mill 15 is connected to the bypass pipe 14, the discharge port is connected to the conveying pipe 2, the air inlet is connected to the main air pipe 7, and an air inlet is provided with an air vent valve 16. A first switching valve 17 is provided on the conveying pipe 2 behind the bypass pipe 14, and a second switching valve 18 is provided on the bypass pipe 14.

[0026] This embodiment can crush the particulate matter cleaned from the delivery pipeline, preventing the ejector from being blocked by potentially large particles.

[0027] In practice, when the pressure gauge reading rises to the set value, the discharge valve of the desulfurizing agent silo is closed, the Roots blower is kept running, the air compressor is turned on, the main purge valve is opened, the first switching valve is closed, the second switching valve is opened, and the vent valve is opened. Starting from the blower outlet valve, the purge valves are opened sequentially to perform high-pressure cleaning of the conveying pipeline until the pressure gauge reading drops to the set value. The cleaned powder enters the airflow pulverizer for crushing to prevent large particles from clogging the injectors. Then, the purge valves are closed one by one, the main purge valve is closed, the second switching valve is closed, the first switching valve is opened, the vent valve is closed, and the discharge valve of the desulfurizing agent silo is slowly opened.

[0028] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the content of this utility model specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A waste incinerator in-furnace desulfurization system, comprising a sprayer arranged in the hearth of a waste incinerator, a conveying pipeline connected with the sprayer and a Roots blower, and a desulfurizer bin connected with the conveying pipeline, wherein a blower outlet valve and a pressure gauge are arranged in sequence on the conveying pipeline; characterized in that: It also includes an air compressor, a compressed air tank, a main air pipe, several purge pipes and a purge valve. The air compressor, compressed air tank and main air pipe are connected in sequence. Several purge pipes are connected to the main air pipe through branch pipes. Each purge pipe is equipped with a purge valve. Several of the purge pipes are located on the horizontal section and bends of the conveying pipeline between the blower outlet valve and the ejector.

2. The in-furnace desulfurization system for a waste incinerator according to claim 1, characterized in that: The purge pipes are inclined and evenly spaced on the horizontal section of the conveying pipeline, with the inclination direction facing the conveying direction and the inclination angle not exceeding 45°. The purge pipe is located on the arc-shaped part outside the bend.

3. The in-furnace desulfurization system for a waste incinerator according to claim 1, characterized in that: The purge pipe is also installed on the vertical section of the conveying pipeline located at an inclination between the blower outlet valve and the ejector, with the inclination direction facing the conveying direction and the inclination angle not exceeding 45°.

4. The in-furnace desulfurization system for a waste incinerator according to claim 3, characterized in that: The spacing between the purge pipes on the vertical section of the conveying pipeline is greater than the spacing between the purge pipes on the horizontal section.

5. The in-furnace desulfurization system for a waste incinerator according to claim 1, characterized in that: The main air pipe is equipped with a purge valve.

6. The in-furnace desulfurization system for a waste incinerator according to any one of claims 1 to 4, characterized in that: The conveying pipe is located at the front end of the injector and is also connected to an airflow pulverizer via a bypass pipe. The outlet of the airflow pulverizer is connected to the conveying pipe, and its inlet is connected to the main air pipe. An air inlet valve is provided on the air inlet. A first switching valve is provided on the conveying pipe behind the bypass pipe, and a second switching valve is provided on the bypass pipe.

7. The in-furnace desulfurization system for a waste incinerator according to claim 6, characterized in that: The air jet mill is a flat air jet mill.

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