Electric heater for flue gas denitration

Abstract

The utility model discloses a flue gas denitration electric heater, including hollow casing and a plurality of electric heating components, the bottom of one end of hollow casing is provided with the air inlet, and the air inlet is connected with the air inlet pipe, and the end away from the air inlet pipe of hollow casing is provided with the air outlet, and the electric heating component is set up in U shape, and the heating section of electric heating component is inserted into the inside of hollow casing and extends to the air outlet of hollow casing, and a plurality of electric heating components are circular equidistance array distribution in the inside of hollow casing, and the inside of hollow casing is fixedly connected with a plurality of guide plates, and the air flowing in the inside of hollow casing is serpentine flow through the guide plate, the electric heating component of the utility model is in U shape and extends to the air outlet, and is designed in cooperation with the circular array distribution and the guide plate, and makes the air in the hollow casing serpentine flow, prolongs the heating residence time, ensures that the export temperature is uniform and stable, avoids the denitration efficiency drop caused by the local heating deficiency.

Description

Technical Field

[0001] This utility model relates to the field of flue gas denitrification technology, and in particular to an electric heater for flue gas denitrification. Background Technology

[0002] In the selective catalytic reduction (SCR) denitrification process, ammonia reacts with nitrogen oxides under the action of a catalyst to achieve denitrification. To ensure the safety and uniformity of the reaction, ammonia is usually diluted with air in a specific ratio before being injected into the reaction system. The diluted ammonia-air mixture needs to be heated to a suitable temperature (generally 180-250℃) to ensure that the ammonia and flue gas are fully mixed and react rapidly. Otherwise, it will lead to problems such as reduced denitrification efficiency and increased ammonia slip. Therefore, it is necessary to heat the air used for dilution.

[0003] Therefore, an electric heater for flue gas denitrification is proposed. Utility Model Content

[0004] The purpose of this invention is to provide an electric heater for flue gas denitrification to solve the temperature requirement for ammonia and flue gas to be fully mixed and react rapidly.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: An electric heater for flue gas denitrification includes a hollow shell and several electric heating components. An air inlet is provided at the bottom of one end of the hollow shell, and the air inlet is connected to an air inlet pipe. An air outlet is provided at the end of the hollow shell away from the air inlet pipe, and the air outlet is connected to an air outlet pipe. The electric heating components are arranged in a U-shape. The heating section of the electric heating components extends into the interior of the hollow shell and extends to the air outlet of the hollow shell. Several electric heating components are distributed in a circular equidistant array inside the hollow shell. Several baffles are fixedly connected inside the hollow shell, and the electric heating component passes through the baffles, causing the air flowing inside the hollow shell to flow in a serpentine pattern.

[0006] As a preferred embodiment of this utility model, the electric heating assembly includes a heating tube, the interior of which is U-shaped, and an electric heating wire is threaded through the interior of the heating tube.

[0007] As a preferred embodiment of this utility model, a junction box is installed at one end of the hollow shell near the air inlet pipe, and the wiring terminal of the electric heating wire is located inside the junction box.

[0008] As a preferred embodiment of this utility model, a first temperature sensor is fixedly installed inside the hollow shell.

[0009] As a preferred embodiment of this utility model, a second temperature sensor is installed on the air outlet duct.

[0010] As a preferred embodiment of this utility model, a temperature indicator is installed on the air outlet duct.

[0011] As a preferred embodiment of this utility model, the outer wall of the hollow shell is wrapped with a heat insulation layer.

[0012] As a further embodiment of this invention, the insulation layer is configured as an aluminum silicate cotton layer.

[0013] As a further embodiment of this utility model, the thickness of the insulation layer is 130mm to 150mm.

[0014] As a preferred embodiment of this utility model, support seats are fixedly installed at the bottom of both ends of the hollow shell.

[0015] Compared with existing technologies, the electric heater for flue gas denitrification provided by this utility model has the following advantages: The electric heating element is U-shaped and extends to the air outlet. Combined with the circular array distribution and the baffle design, the air flows in a serpentine pattern within the hollow shell, extending the heating residence time and ensuring that the outlet temperature is uniformly and stably maintained at 180-250℃, thus avoiding a decrease in denitrification efficiency due to insufficient local heating. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only examples of embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a cross-sectional structural diagram of an embodiment of the present utility model; Figure 2 This is a schematic diagram of the right-side structure of an embodiment of the present utility model.

[0018] Figure label: 1. Hollow shell; 101. Air inlet duct; 102. Air outlet duct; 103. Support base; 2. Heating tube; 3. Guide plate; 4. Insulation layer; 5. Junction box; 6. First temperature sensor; 7. Second temperature sensor; 8. Temperature indicator. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only for explaining the present invention and are not intended to limit the present invention.

[0020] In the description of the embodiments of the present invention, it should be understood that the terms "upper", "lower", "front", "rear", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the embodiments of the present invention 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 the embodiments of the present invention.

[0021] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation", "connection" and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an integral connection, or a detachable connection; they can refer to the internal connection of two components; they can refer to a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present invention should be understood according to the specific circumstances.

[0022] See Figures 1 to 2 As shown, the electric heater for flue gas denitrification in this embodiment of the utility model includes a hollow shell 1 and several electric heating components. An air inlet is provided at the bottom of one end of the hollow shell 1, and the air inlet is connected to an air inlet pipe 101. An air outlet is provided at the end of the hollow shell 1 away from the air inlet pipe 101, and the air outlet is connected to an air outlet pipe 102. The electric heating components are arranged in a U-shape, and the heating section of the electric heating components extends into the interior of the hollow shell 1 and extends to the air outlet of the hollow shell 1. Several electric heating components are distributed in a circular equidistant array inside the hollow shell 1. Several guide plates 3 are fixedly connected inside the hollow shell 1, and the electric heating components pass through the guide plates 3, so that the air flowing inside the hollow shell 1 flows in a serpentine manner through the guide plates 3.

[0023] During operation, the air to be heated enters the hollow housing 1 through the air inlet duct 101. The U-shaped, circularly evenly distributed electric heating elements generate heat when energized, uniformly heating the surrounding air. The guide vane 3 causes the air to flow in a serpentine pattern within the hollow housing 1, extending the air's residence time in the heating zone. This allows the air to fully absorb the heat emitted by the electric heating elements, achieving efficient heating. The heated air then flows out through the air outlet duct 102 and enters the subsequent denitrification reaction system.

[0024] The electric heating element extends to the air outlet, ensuring that the air is continuously heated throughout the entire flow path until it flows out of the hollow shell 1. This prevents the air temperature from dropping due to insufficient heating in the area near the air outlet, making the air temperature at the outlet more uniform and stable to reach the set value. This effectively improves heating efficiency and temperature control accuracy, thereby optimizing the denitrification reaction.

[0025] The electric heating assembly includes a heating tube 2, which has a U-shaped internal structure and an electric heating wire inserted inside. When current passes through the electric heating wire inside the heating tube 2, electrical energy is converted into heat energy according to the thermal effect of the current, causing the electric heating wire to heat up. Because the heating tube 2 is U-shaped, the contact area between the electric heating wire and the air is increased, and the heating path is improved, allowing heat to be transferred to the surrounding air more effectively and improving heating efficiency.

[0026] The heating wire is made of nickel-chromium alloy, and the heating tube 2 is made of carbon steel.

[0027] A junction box 5 is installed at one end of the hollow housing 1 near the air inlet duct 101, and the wiring terminals of the electric heating wire are located inside the junction box 5. The junction box 5 provides a safe and centralized connection space for the wiring terminals of the electric heating wire. The external power supply is connected to the wiring terminals of the electric heating wire through the junction box 5, introducing electrical energy into the electric heating assembly and ensuring that the current can pass smoothly through the electric heating wire to generate heat and operate. At the same time, the junction box 5 also serves a protective function, preventing the wiring terminals from being exposed and causing safety problems.

[0028] A first temperature sensor 6 is fixedly installed inside the hollow shell 1. The first temperature sensor 6 monitors the temperature of the air inside the hollow shell 1 in real time and converts the temperature signal into an electrical signal, which is then transmitted to the control system. Based on this temperature signal, the control system can determine the changes in air temperature during the heating process and then adjust the heating power of the electric heating components to ensure that the internal air temperature remains stable within a suitable range, meeting the requirements of the denitrification process for air heating temperature.

[0029] A second temperature sensor 7 is installed on the air outlet duct 102. The second temperature sensor 7 is used to measure the final temperature of the air flowing out of the air outlet duct 102 after being heated by the electric heater. This temperature data is also fed back to the control system. By comparing it with the set target temperature, the control system can further adjust the working state of the electric heating component to ensure that the output heated air temperature accurately meets the requirements of the denitrification process and ensures the stable progress of the denitrification reaction.

[0030] A temperature indicator 8 is installed on the air outlet duct 102. The temperature indicator 8 directly displays the temperature value of the air in the air outlet duct 102. Operators can intuitively read the current temperature of the heated air from the temperature indicator 8 without the need for additional detection equipment or control system interface, which makes it convenient for operators to monitor the temperature of the heated air in real time and to promptly detect problems such as temperature abnormalities.

[0031] The outer wall of the hollow shell 1 is covered with an insulation layer 4. The insulation layer 4 can effectively reduce the loss of heat from the inside of the hollow shell 1 to the external environment. On the one hand, it improves energy utilization efficiency and reduces the additional energy consumption of the electric heating components due to heat loss; on the other hand, it helps to maintain the stability of the internal temperature of the hollow shell 1, avoids fluctuations in the internal air temperature caused by external environmental factors, ensures the stability and efficiency of the heating process, and keeps the air temperature entering the ammonia evaporator stable.

[0032] In this embodiment, the insulation layer 4 is set as an aluminum silicate cotton layer. Aluminum silicate cotton has good thermal insulation performance, and its fiber structure can effectively prevent heat conduction. Using it as the material of the insulation layer 4 can ensure a certain insulation effect while having good high temperature resistance, and can adapt to the high temperature environment of the outer wall of the hollow shell 1 when the electric heater is working, so as to play a stable insulation role for a long time and reduce heat loss.

[0033] The thickness of the insulation layer 4 is 130mm to 150mm. This thickness of the aluminum silicate cotton insulation layer 4 provides sufficient insulation for the hollow shell 1 while meeting installation space and other requirements. This thickness range effectively controls the rate of heat loss through the insulation layer 4, ensuring that as much internal heat as possible is used to heat the air, improving heating efficiency, and maintaining a stable internal temperature to meet the performance requirements of the electric heater for flue gas denitrification.

[0034] Support bases 103 are fixedly installed at both ends of the hollow shell 1. The support bases 103 provide stable support for the hollow shell 1. Installing them at both ends of the hollow shell 1 allows the electric heater to be placed stably in the installation position, preventing the electric heater from shifting or tipping over due to vibration, external impact, or other factors, thus ensuring the stability and safety of the equipment during operation.

[0035] The foregoing has shown and described the basic principles of the present invention. The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. The above embodiments and descriptions in the specification are only illustrative of the principles of the present invention. Any modifications, equivalent substitutions, and improvements made within the scope of the present invention without departing from the scope of the present invention should be included within the protection scope of the present invention.

Claims

1. An electric heater for flue gas denitrification, characterized in that: The device includes a hollow shell (1) and several electric heating components. One end of the hollow shell (1) has an air inlet at the bottom, which is connected to an air inlet pipe (101). The end of the hollow shell (1) away from the air inlet pipe (101) has an air outlet, which is connected to an air outlet pipe (102). The electric heating components are arranged in a U-shape. The heating section of the electric heating components extends into the interior of the hollow shell (1) and extends to the air outlet of the hollow shell (1). Several electric heating components are arranged in a circular equidistant array inside the hollow shell (1). The hollow shell (1) has several guide plates (3) fixedly connected inside. The electric heating component passes through the guide plates (3), and the air flowing inside the hollow shell (1) flows in a serpentine manner through the guide plates (3).

2. The electric heater for flue gas denitrification according to claim 1, characterized in that: The electric heating assembly includes a heating tube (2), the interior of which is U-shaped, and an electric heating wire is inserted inside the heating tube (2).

3. The electric heater for flue gas denitrification according to claim 2, characterized in that: A junction box (5) is installed at one end of the hollow shell (1) near the air inlet pipe (101), and the wiring terminal of the electric heating wire is located inside the junction box (5).

4. The electric heater for flue gas denitrification according to claim 1, characterized in that: The first temperature sensor (6) is fixedly installed inside the hollow shell (1).

5. The electric heater for flue gas denitrification according to claim 1, characterized in that: A second temperature sensor (7) is installed on the air outlet pipe (102).

6. The electric heater for flue gas denitrification according to claim 1, characterized in that: A temperature indicator (8) is installed on the air outlet duct (102).

7. The electric heater for flue gas denitrification according to claim 1, characterized in that: The outer wall of the hollow shell (1) is covered with a thermal insulation layer (4).

8. The electric heater for flue gas denitrification according to claim 7, characterized in that: The insulation layer (4) is set as an aluminum silicate cotton layer.

9. The electric heater for flue gas denitrification according to claim 8, characterized in that: The thickness of the insulation layer (4) is 130mm to 150mm.

10. The electric heater for flue gas denitrification according to claim 7, characterized in that: The hollow shell (1) has support bases (103) fixedly installed at both ends of the bottom.

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