Dry powder adding system suitable for waste incineration power plant
By adopting the lower conical cylindrical structure and heating assembly of the weighing bucket in the dry powder dosing system, combining the cylindrical cylindrical structure and the inert gas access port, the problem of inaccurate dry powder weight control is solved, and accurate dry powder dosing is achieved, reducing waste and operating costs.
Patent Information
- Application Number
- CN202422291629.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-19
- Publication Date
- 2025-07-22
- Estimated Expiration
- 2034-09-19
AI Technical Summary
The existing dry powder dosing system cannot control the weight of dry powder that specifically enters the dry powder pipeline, and the weight of dry powder used by a single user cannot be accurately calculated, resulting in excessive dry powder disposal and waste, increasing the operating costs of the enterprise.
The lower conical cylindrical structure of the weighing bucket is adopted, and the outside is equipped with heating components and weight sensors. Combined with the cylindrical cylindrical structure and an inert gas access port, real-time monitoring and control of the dry powder weight, and precisely adding dry powder through the venturi tube and the Roots fan.
It realizes precise control of the weight of dry powder for individual users, reduces dry powder waste, reduces operating costs, and ensures the normal operation of the dry powder injection system.
Smart Images
Figure CN223137891U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of waste incineration treatment, and particularly relates to a dry powder feeding system applicable to a waste incineration power plant. Background Art
[0002] The existing dry powder feeding device of a waste incineration power plant has a dry powder storage bin. The upper part of the dry powder storage bin is a circular straight cylinder, and the lower part is a cone. A flap valve is arranged below the cone to control the flow of dry powder in the dry powder bin; a disc feeder is arranged below the flap valve to supply dry powder to a single user; several pan feeders are arranged below the disc feeder to convey the dry powder in the disc feeder into a dry powder pipeline; one side of the dry powder pipeline is connected to a dry powder roots blower to provide power to blow the dry powder in the dry powder pipeline into a flue gas purification flue, and the other side of the dry powder pipeline is connected to the flue gas purification flue.
[0003] In the prior art of waste incineration power plants, there are mainly two methods for treating acidic gases in flue gas. On the one hand, a high-speed rotating sprayer is used to atomize a lime slurry solution and then react with the acidic gas. This method can remove 80% of the acidic gas; on the other hand, dry powder is sprayed at the flue gas purification pipeline. The components of the dry powder generally include two types: calcium hydroxide or sodium bicarbonate. The main function is to use the alkaline substances in calcium hydroxide or sodium bicarbonate to chemically react with the acidic gas in the flue gas, so as to achieve the purpose of removing the acidic gas in the flue gas.
[0004] In a waste incineration power plant, generally a set of two acidic gas treatment systems will be arranged. During normal operation, the main means is to spray a lime slurry solution with a high-speed rotating sprayer. When the concentration of acidic gas in the flue gas abnormally increases and the high-speed rotating sprayer spraying the lime slurry solution cannot reduce the concentration of acidic gas below the emission standard, it is necessary to start the dry powder spraying device to neutralize the acidic gas in the flue gas. In the prior art, the weighing device of the dry powder feeding device can only monitor the weight change of the dry powder storage bin and cannot monitor the usage amount of a single user. When the content of acidic gas in the flue gas increases and the dry powder spraying device needs to be started, the dry powder in the dry powder storage bin enters the dry powder pipeline through the disc feeder and the pan feeder. This method cannot control the specific weight of the dry powder entering the dry powder pipeline, and the weight of the dry powder used by a single user cannot be accurately calculated. Therefore, during the actual operation process, in order to ensure that the flue gas index emission is qualified, the dry powder is bound to be over-dosed. If the dry powder system needs to operate for a long time, it will inevitably cause serious waste of dry powder and increase the operation cost of the enterprise. Content of the Utility Model
[0005] The technical problem to be solved by the present utility model is to provide a dry powder dosing system applicable to waste incineration power plants, which is compact in structure, convenient to operate, and high in control accuracy, aiming at the deficiencies that the existing dry powder dosing system cannot control the weight of dry powder entering the dry powder pipeline, and the weight of dry powder used by a single user cannot be accurately calculated. To achieve the above object, the present utility model can adopt the following technical solutions:
[0006] A dry powder dosing system applicable to waste incineration power plants, comprising: a dry powder storage bin, a weighing hopper, a screw feeder, a Venturi tube, and a Roots blower; the lower part of the weighing hopper adopts a conical cylinder structure, and a heating component and a weight sensor for measuring the weight of dry powder are arranged outside the conical cylinder. The heating component includes an electric tracing wire and an electric heater. The electric tracing wire is evenly wound around the outer wall of the conical cylinder, and the electric tracing wire is electrically connected to the electric heater for heating the dry powder in the weighing hopper; the discharge port of the dry powder storage bin is connected to the feed port of the weighing hopper through a connecting pipeline with a flap valve and a pneumatic door. The discharge port of the weighing hopper is connected to the feed port of the screw feeder. The discharge port of the screw feeder is connected to the top inlet on the side of the throat of the Venturi tube through a connecting pipeline with a star-shaped ash discharge valve. The Roots blower is connected to the inlet of the Venturi tube through a dry powder conveying pipeline, and the outlet of the Venturi tube is connected to the flue gas purification pipeline through a dry powder conveying pipeline to realize the dry powder dosing.
[0007] As a further improvement of the present utility model, the upper part of the weighing hopper adopts a cylindrical cylinder structure, and an exhaust port and an inert gas inlet are arranged at the top of the cylindrical cylinder.
[0008] As a further improvement of the present utility model, a high-level alarm device is arranged at the upper part of the cylindrical cylinder, and a low-level alarm device is arranged at the lower part of the cylindrical cylinder. The pneumatic door, the high-level alarm device, the low-level alarm device, and the weight sensor are all connected to a remote monitoring device to realize real-time automatic monitoring of the weight of dry powder in the weighing hopper.
[0009] As a further improvement of the present utility model, two weight sensors are arranged outside the conical cylinder of the weighing hopper.
[0010] As a further improvement of the present utility model, a filter screen is arranged in the exhaust port.
[0011] As a further improvement of the present utility model, a variable-frequency blower is further included, and the output end of the variable-frequency blower is connected to the screw feeder.
[0012] As a further improvement of the present utility model, the connecting pipelines between the dry powder storage bin, the flap valve, the pneumatic door, and the weighing hopper are carbon steel pipelines.
[0013] As a further improvement of the present utility model, a heat preservation assembly is further provided outside the conical cylinder of the weighing hopper. The heat preservation assembly includes heat preservation cotton and an outer protection plate. The heat preservation cotton is wrapped and covered outside the outer side wall where the electric tracing wire is wound, and the outer protection plate is fixedly arranged outside the heat preservation cotton.
[0014] As a further improvement of the present utility model, the connecting pipe between the discharge port of the screw feeder and the star-shaped ash discharge valve is a carbon steel pipe, and the connecting pipe between the star-shaped ash discharge valve and the venturi tube is a steel wire hose.
[0015] As a further improvement of the present utility model, the upper part of the dry powder storage bin is a cylindrical barrel, and the lower part of the dry powder storage bin is a conical barrel.
[0016] Compared with the prior art, the advantages of the present utility model are as follows:
[0017] The dry powder dosing system of the present utility model is applicable to waste incineration power plants. By setting the lower part of the weighing hopper as a conical cylinder structure, it is convenient for the smooth flow of dry powder. At the same time, a heating assembly and a weight sensor are also arranged outside the conical cylinder. The weight sensor is used to monitor and measure the weight of the dry powder in real time, realizing the separate measurement of the dry powder dosing amount of each incinerator, facilitating the quantitative dosing according to the content of acidic gases in the flue gas during the operation of the power plant, reducing the waste of dry powder, and saving the operation cost; the heating assembly includes an electric tracing wire and an electric heater. The electric tracing wire is evenly wound on the outer side wall of the conical cylinder, and the electric tracing wire is electrically connected to the electric heater, which can effectively prevent the dry powder that has not been used up in the weighing hopper from being damp and caking, ensuring the normal operation of the dry powder dosing system; in addition, the star-shaped ash discharge valve can evenly convey the dry powder to the venturi tube and can effectively isolate the venturi tube from the screw feeder, preventing the negative pressure of the venturi tube from directly sucking the dry powder in the screw feeder, making the dosage of the dry powder more controllable. Description of the Drawings
[0018] Figure 1 It is a schematic structural principle diagram of the dry powder dosing system applicable to waste incineration power plants in a specific embodiment of the present utility model;
[0019] Legend: 1. Dry powder storage bin; 2. Slide valve; 3. Pneumatic door; 4. Weighing hopper; 5. Screw feeder; 6. Star-shaped ash discharge valve; 7. Venturi tube; 8. Roots blower; 9. Exhaust port; 10. High level alarm device; 11. Low level alarm device; 12. Heating assembly; 13. Variable frequency blower; 14. Weight sensor; 15. Dry powder conveying pipeline; 16. Flue gas purification pipeline; 17. Inert gas inlet; 18. Steel wire hose. Detailed Embodiment
[0020] The following further describes the present utility model in conjunction with the specification drawings and specific preferred embodiments, but does not limit the protection scope of the present utility model accordingly.
[0021] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by terms such as "side part", "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial direction", "radial direction", "circumferential direction", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model.
[0022] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, the meaning of "a plurality" is two or more, unless otherwise specifically defined.
[0023] Embodiment
[0024] As Figure 1 shown, the dry powder dosing system applicable to a waste incineration power plant of the present utility model includes: a dry powder storage bin 1, a weighing hopper 4, a screw feeder 5, a Venturi tube 7, and a Roots blower 8. The lower part of the weighing hopper 4 adopts a conical cylinder structure, and a heating assembly 12 and a weight sensor 14 for measuring the weight of the dry powder are provided on the outer side of the conical cylinder. The heating assembly 12 includes an electric heating trace and an electric heater. The electric heating trace is evenly wound around the outer wall of the conical cylinder, and the electric heating trace is electrically connected to the electric heater to heat the dry powder in the weighing hopper 4. The discharge port of the dry powder storage bin 1 is connected to the feed port of the weighing hopper 4 through a connecting pipe with a flap valve 2 and a pneumatic door 3. The discharge port of the weighing hopper 4 is connected to the feed port of the screw feeder 5. The discharge port of the screw feeder 5 is connected to the top inlet on the side of the throat of the Venturi tube 7 through a connecting pipe with a rotary air lock valve 6. The Roots blower 8 is connected to the inlet of the Venturi tube 7 through a dry powder conveying pipe 15. The outlet of the Venturi tube 7 is connected to a flue gas purification pipe 16 through the dry powder conveying pipe 15. The Roots blower 8 blows air with a pressure of 2 kPa into the dry powder conveying pipe 15. After passing through the Venturi tube 7, a large negative pressure is generated at the throat position of the Venturi tube 7, which can quickly suck in the dry powder dropped by the rotary air lock valve 6 and send it into the flue gas purification pipe 16 to achieve precise dosing of the dry powder.
[0025] Furthermore, the upper part of the dry powder storage bin 1 is a cylindrical cylinder, and the lower part of the dry powder storage bin 1 is a conical cylinder. In actual operation, the composition of the dry powder is generally calcium hydroxide or sodium bicarbonate, both of which have strong hydrolysis and are easily damp and hardened. Once damp, the system will fail to operate. Therefore, a vibrating device can be set at the lower part of the dry powder storage bin 1 to vibrate the dry powder in the dry powder storage bin 1 from time to time to avoid dry powder hardening. The connecting pipes between the dry powder storage bin 1, the gate valve 2, the pneumatic door 3 and the weighing bucket 4 are carbon steel pipes. During operation, the gate valve 2 remains in a normally open state; the pneumatic door 3 can be remotely automatically controlled, and an automatic switch program can be set, which is related to the weight monitored by the weighing sensor 14 on the weighing bucket 4. The specific logic can be that the pneumatic door 3 is automatically opened when the weight of the weighing sensor 14 is less than 5kg, and the pneumatic door 3 is automatically closed when the weight is greater than 80kg. In the actual operation process, the upper and lower limits of the automatic opening and closing of the pneumatic door 3 can be flexibly adjusted according to the specific operating conditions.
[0026] In this embodiment, by setting the lower part of the weighing bucket 4 to a conical cylinder structure, the dry powder can flow smoothly. At the same time, a heating component 12 and a weight sensor 14 are set on the outside of the conical cylinder. The weight of the dry powder is monitored in real time by the weight sensor 14, so that the dosage of the dry powder can be measured separately. The heating component 12 includes an electric heating wire and an electric heater. The electric heating wire is evenly wound around the outer wall of the conical cylinder. The electric heating wire is electrically connected to the electric heater, which can effectively prevent the unused dry powder in the weighing bucket 4 from being damp and hardened, ensuring the normal operation of the dry powder dosing system. In addition, the star-shaped ash discharge valve 6 is used to rotate the dry powder transported by the screw feeder 5 to the venturi tube 7 through the rotation of the blade driven by the motor. It also has a good air-locking and sealing function, ensuring a good negative pressure in the venturi tube 7. That is, the star-shaped ash discharge valve 6 can evenly transfer the dry powder to the venturi tube 7, and can effectively isolate the venturi tube 7 from the screw feeder 5, preventing the negative pressure of the venturi tube 7 from directly sucking the dry powder in the screw feeder 5, so that the amount of dry powder is more controllable.
[0027] like Figure 1 As shown, the upper portion of the weighing bucket 4 adopts a cylindrical structure, and an exhaust port 9 and an inert gas inlet 17 are provided on the top of the cylinder.
[0028] Furthermore, a high material level alarm device 10 is provided at the upper part of the cylinder, and a low material level alarm device 11 is provided at the lower part of the cylinder. The pneumatic door 3, the high material level alarm device 10, the low material level alarm device 11 and the weight sensor 14 are all connected to a remote monitoring device (not shown in the figure) to realize real-time automatic monitoring of the weight of the dry powder in the weighing bucket 4. It can be seen that the remote monitoring device can adopt a PLC control device, which has the characteristics of simple principle and precise control, so as to improve the degree of automation of dry powder addition.
[0029] In this embodiment, the weighing hopper 4 is a combination of a cylinder and a cone. The upper part of the cylinder is sealed, and the lower part of the cone is tightly connected to the screw feeder 5. An exhaust port 9 is provided above the weighing hopper 4, and there is a dry powder filter screen at the exhaust port 9 to prevent dry powder from escaping when the weighing hopper 4 is under positive pressure. A high-level alarm device 10 and a low-level alarm device 11 are provided on the weighing hopper 4. When the high-level alarm is triggered, the pneumatic door 3 will automatically close. When the low-level alarm is triggered, the pneumatic door 3 will automatically open. An inert gas inlet 17 is provided at the top of the weighing hopper 4. When the index of acidic gas is normal and dry powder is not needed, inert gas (such as nitrogen) is continuously flushed into the weighing hopper 4 to reduce the moisture content in the weighing hopper 4 and effectively prevent the remaining dry powder in the weighing hopper 4 from getting damp and caking.
[0030] In this embodiment, two weight sensors 14 are provided on the outer side of the conical cylinder of the weighing hopper 4. When there is no dry powder in the weighing hopper 4, the weight is set to 0 kg. When the dry powder in the dry powder storage bin 1 enters the weighing hopper 4, the weight sensors 14 can effectively monitor the weight of the dry powder in the weighing hopper 4 to improve the reliability and accuracy of dry powder weighing and metering.
[0031] As Figure 1 shown, it further includes a variable-frequency blower 13. The output end of the variable-frequency blower 13 is connected to the screw feeder 5, and the dosing amount of dry powder can be adjusted according to the concentration of acidic gas in the flue gas.
[0032] In this embodiment, a heat preservation component (not shown in the figure) is further provided on the outer side of the conical cylinder of the weighing hopper 4 to improve the thermal energy utilization rate. The heat preservation component includes heat preservation cotton and an outer protection plate. The heat preservation cotton is wrapped around the outer side wall of the electric heating wire winding, and the outer protection plate is fixed outside the heat preservation cotton. The water absorption of dry powder is extremely good. Once it gets damp, it will agglomerate and cannot be fed through the screw feeder 5, seriously affecting the use of the system. By continuously heating the weighing hopper 4 through the heating component 12, the inside of the weighing hopper is kept dry, which can effectively prevent the dry powder in the weighing hopper 4 from getting damp.
[0033] In this embodiment, the connecting pipe between the discharge port of the screw feeder 5 and the rotary air lock valve 6 is a carbon steel pipe to enable the dry powder to flow smoothly according to its own weight. The connecting pipe between the rotary air lock valve 6 and the venturi tube 7 is a steel wire hose 18 to prevent weighing errors caused by the self-weight of the connecting pipe.
[0034] In this embodiment, the working process of the dry powder dosing system is as follows:
[0035] As Figure 1As shown, the dry powder enters the weighing hopper 4 in the dry powder storage bin 1 through the slide gate valve 2 and the pneumatic door 3. The weighing hopper 4 can hold approximately 100 kg of dry powder. The dry powder in the weighing hopper 4 is continuously conveyed into the Venturi tube 7 through the screw feeder 5 below. A rotary air lock valve 6 is provided between the screw feeder 5 and the Venturi tube 7, and its function is to prevent the negative pressure at the Venturi tube from directly sucking the dry powder in the weighing hopper away. The appropriate air pressure provided by the Roots blower 8 blows the dry powder in the dry powder conveying pipeline 15 into the flue gas purification pipeline 16. Due to its special structure, the low-speed air pressure generated by the Roots blower 8 will be accelerated to form a high-speed air pressure after passing through the Venturi tube 7. At this time, a local high negative pressure is formed at the Venturi tube 7, sucking the dry powder conveyed by the screw feeder 5 into the dry powder conveying pipeline 15 and finally sent into the flue gas purification pipeline 16.
[0036] Although the present utility model is disclosed above with preferred embodiments, it is not intended to limit the present utility model. Any person skilled in the art can make many possible changes and modifications to the technical solution of the present utility model, or modify it into an equivalent embodiment with equivalent changes, without departing from the spirit and technical solution of the present utility model. Therefore, any simple modification, equivalent replacement, equivalent change and modification made to the above embodiments based on the technical essence of the present utility model without departing from the technical solution of the present utility model still fall within the scope of protection of the technical solution of the present utility model.
Claims
1. A dry powder dosing system applicable to waste incineration power plants, characterized in that Including: A dry powder storage bin (1), a weighing hopper (4), a screw feeder (5), a Venturi tube (7) and a Roots blower (8); the lower part of the weighing hopper (4) adopts a conical cylinder structure, and a heating assembly (12) and a weight sensor (14) for measuring the weight of the dry powder are arranged on the outer side of the conical cylinder. The heating assembly (12) includes an electric heating tape and an electric heater. The electric heating tape is evenly wound on the outer side wall of the conical cylinder, and the electric heating tape is electrically connected to the electric heater for heating the dry powder in the weighing hopper (4); the discharge port of the dry powder storage bin (1) is connected to the feed port of the weighing hopper (4) through a connecting pipe with a flap valve (2) and a pneumatic door (3). The discharge port of the weighing hopper (4) is connected to the feed port of the screw feeder (5). The discharge port of the screw feeder (5) is connected to the top inlet on the side of the throat of the Venturi tube (7) through a connecting pipe with a rotary air lock valve (6). The Roots blower (8) is connected to the inlet of the Venturi tube (7) through a dry powder conveying pipe (15). The outlet of the Venturi tube (7) is connected to a flue gas purification pipe (16) through a dry powder conveying pipe (15) to realize the dry powder feeding.
2. The dry powder dosing system applicable to a waste incineration power plant according to claim 1, characterized in that, The upper part of the weighing hopper (4) adopts a cylindrical cylinder structure, and an exhaust port (9) and an inert gas inlet (17) are arranged at the top of the cylindrical cylinder.
3. The dry powder dosing system applicable to waste incineration power plants according to claim 2, characterized in that, A high-level alarm device (10) is arranged on the upper part of the cylindrical cylinder, and a low-level alarm device (11) is arranged on the lower part of the cylindrical cylinder. The pneumatic door (3), the high-level alarm device (10), the low-level alarm device (11) and the weight sensor (14) are all connected to a remote monitoring device to realize real-time automatic monitoring of the weight of the dry powder in the weighing hopper (4).
4. The dry powder dosing system applicable to a waste incineration power plant according to claim 3, characterized in that, Two weight sensors (14) are arranged on the outer side of the conical cylinder of the weighing hopper (4).
5. The dry powder dosing system applicable to a waste incineration power plant according to claim 2, wherein A filter screen is arranged in the exhaust port (9).
6. The dry powder dosing system applicable to waste incineration power plants according to any one of claims 1 to 5, characterized in that, It also includes a variable-frequency blower (13), and the output end of the variable-frequency blower (13) is connected to the screw feeder (5).
7. The dry powder dosing system applicable to a waste incineration power plant according to any one of claims 1 to 5, characterized in that The connecting pipes between the dry powder storage bin (1), the flap valve (2), the pneumatic door (3) and the weighing hopper (4) are carbon steel pipes.
8. The dry powder dosing system applicable to a waste incineration power plant according to any one of claims 1 to 5, characterized in that, A heat preservation assembly is also arranged on the outer side of the conical cylinder of the weighing hopper (4). The heat preservation assembly includes heat preservation cotton and an outer protection plate. The heat preservation cotton wraps and covers the outer side wall outside the winding of the electric heating tape, and the outer protection plate is fixed outside the heat preservation cotton.
9. The dry powder dosing system applicable to a waste incineration power plant according to any one of claims 1 to 5, characterized in that, The connecting pipe between the discharge port of the screw feeder (5) and the rotary air lock valve (6) is a carbon steel pipe, and the connecting pipe between the rotary air lock valve (6) and the Venturi tube (7) is a steel wire hose (18).
10. The dry powder dosing system applicable to a waste incineration power plant according to any one of claims 1 to 5, characterized in that, The upper part of the dry powder storage bin (1) is a cylindrical cylinder, and the lower part of the dry powder storage bin (1) is a conical cylinder.