A positive and negative pressure powder conveying system

Abstract

The utility model discloses a positive and negative pressure powder conveying system belongs to chemical powder conveying technical field. It includes the rotatory blower, buffer tank and powder unloading equipment that connect gradually, still includes filter all -in -one, weighing bin and reaction container simultaneously, and filter all -in -one is equipped with filter bag filter in, and weighing bin is equipped with weighing device in, filter all -in -one and weighing bin integral installation, and the discharge port of powder unloading equipment is connected the feed port of weighing bin, and the discharge port of weighing bin is connected reaction container, and the air intake of filter all -in -one is connected the air inlet of rotatory blower through the air inlet control valve. The utility model discloses can realize the quantitative circulation of powder conveying, and the powder quality of entering reaction container is controlled accurately, and the gas circulation is used simultaneously, and energy consumption is reduced effectively.

Description

Technical Field

[0001] This utility model belongs to the field of chemical powder conveying technology, and more specifically, relates to a positive and negative pressure powder conveying system. Background Technology

[0002] Powders are commonly used as raw materials in product manufacturing. Powder conveying is widely used for transporting light, dry powders such as food powders, agricultural powders, metal powders, and chemical powders. Common conveying methods include pneumatic conveying and tubular chain conveying. Currently, traditional powder conveying machinery is relatively mature. However, due to its large size, high noise, and low precision, it is only suitable for conveying large quantities of powder. Furthermore, it easily generates a large amount of dust during material discharge, polluting the production environment and affecting worker health.

[0003] For example, Chinese patent application number CN202111656244.1, published on March 8, 2022, discloses a gas-powder conveying device without backflow, which includes a fan, a mixer, a discharge hopper, and a storage hopper. The mixer includes a mixing pipe extending horizontally, and a discharge pipe installed on the upper side of the mixing pipe. The mixing pipe is divided into an air inlet section and a mixing section by the discharge pipe. A spiral plate is provided in the air inlet section, and an air inlet connector is provided at the end of the air inlet section. An expansion pipe is installed at the end of the mixing section. The lower end of the discharge pipe is formed as a discharge port, which extends downward into the mixing pipe. The outlet of the fan is connected to the air inlet connector, the expansion pipe is connected to the storage hopper via a conveying pipe, and the discharge port at the bottom of the discharge hopper is connected to the discharge pipe via the inlet pipe.

[0004] This solution uses traditional powder conveying machinery, which struggles to achieve precise quantitative powder delivery and is unsuitable for situations requiring the transfer of powder to a quantitative reaction vessel. Furthermore, to prevent dust explosions during powder transport, a nitrogen atmosphere is typically used. However, if this solution were to use a nitrogen atmosphere, it would result in significant nitrogen consumption, greatly increasing costs. Summary of the Invention

[0005] 1. The problem to be solved To address the problem that existing powder conveying machinery is unsuitable for situations requiring the conveying of powder to a quantitative reaction vessel, this invention provides a positive and negative pressure powder conveying system that enables quantitative cyclic conveying of powder, precisely controls the quality of powder entering the reaction vessel, and simultaneously recycles the conveying gas, effectively reducing energy consumption.

[0006] 2. Technical Solution To solve the above problems, the present invention adopts the following technical solution.

[0007] A positive and negative pressure powder conveying system includes a Roots blower, a buffer tank, and a powder feeding device. The outlet of the Roots blower is connected to a recirculation inlet valve at the inlet of the buffer tank via an exhaust control valve. The buffer tank is connected to an external nitrogen source via an external nitrogen supply inlet valve. The outlet of the buffer tank is connected to the inlet of a mixing and acceleration chamber via an exhaust valve. The discharge port of the powder feeding device is connected to the inlet of the mixing and acceleration chamber via a rotary airlock valve. It also includes an integrated filter, a weighing silo, and a reaction vessel. The integrated filter is equipped with a filter bag filter, and the weighing silo is equipped with a weighing device. The integrated filter and the weighing silo are installed as a single unit. The outlet of the mixing acceleration chamber is connected to the inlet of the weighing silo, and the outlet of the weighing silo is connected to the reaction vessel. The exhaust port of the integrated filter is connected to the inlet of the Roots blower through an intake control valve.

[0008] As a further improvement to the technical solution, the integrated filter has two units, and the weighing hopper is correspondingly provided with two units; the outlet of the mixing acceleration chamber is connected to the inlet of the feed three-way valve, and the two outlets of the feed three-way valve are respectively connected to the inlets of the two weighing hoppers; the exhaust ports of the two integrated filters are respectively connected to the two inlets of the exhaust three-way valve, and the outlet of the exhaust three-way valve is connected to the intake control valve.

[0009] As a further improvement to the technical solution, the discharge port of the weighing hopper is equipped with a rotary airlock valve.

[0010] As a further improvement to the technical solution, the weighing hopper is equipped with a venting disc.

[0011] As a further improvement to the technical solution, the weighing hopper is equipped with a pneumatic hammer.

[0012] As a further improvement to the technical solution, the exhaust valve is connected to the mixing and acceleration chamber via a pipe, and the pipe is equipped with an intake filter and an intake valve.

[0013] As a further improvement to the technical solution, the exhaust control valve is connected to the recirculation intake valve through a pipeline, and the pipeline is equipped with a condenser and a gas-water separator.

[0014] As a further improvement to the technical solution, the pipeline is also equipped with an activated carbon filter.

[0015] As a further improvement to the technical solution, the three-way valve for air extraction is connected to the air intake control valve through a pipeline, and the pipeline is equipped with an anti-clogging device and a secondary air intake filter.

[0016] As a further improvement to the technical solution, a safety valve is provided at the top of the buffer tank.

[0017] 3. Beneficial effects Compared with the prior art, the beneficial effects of this utility model are as follows: (1) The present invention provides a positive and negative pressure powder conveying system, which is equipped with a weighing hopper and a weighing sensor, which can monitor the powder weight in real time and synchronize the data to the PLC controller to ensure that the set weight and actual weight of the powder material stored in the weighing hopper are within the allowable error range, and ensure the accurate weight of the powder material put into the reaction vessel. In addition, by setting an air intake control valve and an exhaust control valve, the exhaust generated by the negative pressure of the Roots blower can be used as a positive pressure driving gas source to reduce energy consumption. Moreover, the positive and negative pressure gas conveying process is a fully enclosed pipeline connection, which can effectively reduce nitrogen consumption and save costs while maintaining a nitrogen atmosphere to prevent dust explosion. (2) The present invention provides a positive and negative pressure powder conveying system. By installing a condenser on the circulating gas pipeline at the air inlet of the buffer tank, the exhaust temperature can be reduced, ensuring that the positive pressure circulating gas operates at room temperature. A gas-water separator is installed on the pipeline to remove moisture from the gas, thereby ensuring the quality of the conveyed products. (3) In order to prevent corrosion of downstream equipment and pipelines and extend the service life of the equipment, the positive and negative pressure powder conveying system of this utility model is equipped with an activated carbon filter on the circulating gas pipeline at the air inlet of the buffer tank, which can adsorb other impurities in the circulating gas and ensure that the gas is pure and meets the process requirements. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a positive and negative pressure powder conveying system according to the present invention; In the picture: 1. Roots blower; 11. Inlet control valve; 12. Exhaust control valve; 13. Anti-clogging device; 14. Secondary inlet filter; 15. Condenser; 16. Gas-liquid separator; 17. Activated carbon filter; 2. Buffer tank; 21. External nitrogen inlet valve; 22. Circulating inlet valve; 23. Exhaust valve; 24. Safety valve; 25. Nitrogen filter; 3. Powder feeding equipment; 31. Inlet filter; 32. Inlet valve; 33. Rotary airlock valve; 34. Mixing acceleration chamber; 4A. Integrated filter machine; 41. Three-way exhaust valve; 41A. Exhaust valve inlet; 42A. Exhaust port; 4B. Integrated filter; 41B. Exhaust valve inlet; 42B. Exhaust port; 5A. Weighing hopper; 51. Three-way feed valve; 51A. Three-way valve outlet; 52A. Feed inlet; 53A. Rotary airlock valve; 54A. Explosion relief disc; 55A. Pneumatic hammer; 5B. Weighing hopper; 51B. Three-way valve outlet; 52B. Feed inlet; 53B. Rotary airlock valve; 54B. Explosion relief disc; 55B. Pneumatic hammer; 6. Reaction vessel. Detailed Implementation

[0019] Exemplary embodiments of the present invention are described in detail below. While these exemplary embodiments have been described in sufficient detail to enable those skilled in the art to practice the present invention, it should be understood that other embodiments may be implemented and various changes may be made to the present invention without departing from its spirit and scope. The more detailed description of embodiments of the present invention below is not intended to limit the scope of the claimed invention, but is merely illustrative and does not limit the description of the features and characteristics of the invention, in order to provide the best mode for carrying out the invention and sufficient to enable those skilled in the art to practice it. Therefore, the scope of the present invention is defined only by the appended claims.

[0020] Example 1 like Figure 1 As shown, a positive and negative pressure powder conveying system is described, with each valve controlled by a PLC. The system includes a Roots blower 1, a buffer tank 2, and a powder feeding device 3. The outlet of the Roots blower 1 is connected to the recirculation inlet valve 22 at the inlet of the buffer tank 2 via an exhaust control valve 12. The buffer tank 2 is connected to an external nitrogen source via an external nitrogen supply inlet valve 21, with a nitrogen filter installed at the front end of the valve to filter out other impurities in the pipeline and prevent them from affecting product quality. The outlet of the buffer tank 2 is connected to the inlet of a mixing acceleration chamber 34 via an exhaust valve 23, and the discharge port of the powder feeding device 3 is connected to the inlet of the mixing acceleration chamber 34 via a rotary airlock valve 33. In this embodiment, the powder feeding device 3 is a dryer.

[0021] The buffer tank 2 is equipped with a pressure sensor. When the pressure is less than the set value, the PLC control system automatically adjusts the opening and closing of the external nitrogen inlet valve 21 to replenish the gas pressure in the buffer tank and keep the buffer tank operating at the normal working pressure. The top of the buffer tank 2 is equipped with a safety valve to prevent overpressure in the buffer tank 2 in case of system failure, ensuring the safe and stable operation of the system and extending the service life of the equipment.

[0022] In addition, it includes an integrated filtration unit, a weighing hopper, and a reaction vessel 6. The integrated filtration unit is equipped with a bag filter and a pulse-type dust removal device to achieve automated dust removal of the filter bags. The weighing hopper is equipped with a weighing device, which is a weighing sensor in this embodiment. The integrated filtration unit and the weighing hopper are vertically integrated, that is, the integrated filtration unit is directly installed on the top of the weighing hopper and tightly connected to the weighing hopper to prevent dust leakage. The outlet of the mixing acceleration chamber 34 is connected to the inlet of the weighing hopper, and the outlet of the weighing hopper is connected to the reaction vessel 6.

[0023] In this embodiment, there are two integrated filters and two corresponding weighing hoppers. The two weighing hoppers work together to deliver powder to the reaction vessel 6. If one weighing hopper fails, the other can still be used to ensure continuous powder delivery and avoid blockage caused by a large output from a single weighing hopper.

[0024] Specifically, the air extraction port 42A of the integrated filter 4A is connected to the air extraction valve inlet 41A of the three-way air extraction valve 41, and the air extraction port 42B of the integrated filter 4B is connected to the air extraction valve inlet 41B of the three-way air extraction valve 41. The air outlet of the three-way air extraction valve 41 is connected to the air inlet control valve 11 via a pipeline. The feed inlet 52A of the weighing hopper 5A is connected to the three-way valve outlet 51A of the feeding three-way valve 51, and the feed inlet 52B of the weighing hopper 5B is connected to the three-way valve outlet 51B of the feeding three-way valve 51. The outlet of the mixing acceleration chamber 34 is connected to the inlet of the feeding three-way valve 51. The positive and negative pressure powder segmented conveying system is modularly designed, and collaborative operation is achieved through pneumatic switching, realizing intelligent joint control operation of the conveying system. Real-time data is fed back to the PLC system for analysis, ensuring the stability and safety of the system in unmanned operation.

[0025] Once the system monitors and detects that the weight of weighing silos 5A or 5B has reached the set value, the system stops operating and awaits unloading into the reaction vessel 6. The discharge port of weighing silos 5A or 5B is equipped with a rotary airlock valve 53A or 53B. Activating the unloading button starts the rotary airlock valve 53A or 53B, ensuring stable unloading. Airflow backflow is controlled through blade gaps to maintain stable pressure in weighing silos 5A or 5B, preventing material accumulation and blockage. Variable frequency speed control regulates powder flow to meet the continuous feeding requirements of the reaction vessel. Weighing silos 5A or 5B are equipped with pneumatic hammers 55A or 55B. Powered by compressed air, the hammers release impact force instantaneously to the silo wall, breaking up material bridges and preventing accumulation. Weighing silos 5A or 5B are equipped with explosion vents 54A and 54B to ensure safe and stable system operation and extend equipment lifespan.

[0026] In this embodiment, the exhaust control valve 12 is connected to the recirculation intake valve 22 via a pipeline. The pipeline is equipped with a condenser 15, a gas-liquid separator 16, and an activated carbon filter. The condenser 15 reduces the exhaust temperature, ensuring the positive pressure recirculation gas operates at room temperature. The gas-liquid separator 16 removes moisture from the gas, thus ensuring the quality of the transported products. The activated carbon filter 17 adsorbs other impurities in the recirculation gas, ensuring the gas is pure and meets process requirements, preventing corrosion of downstream equipment and pipelines, and extending equipment lifespan.

[0027] Meanwhile, the pipes connecting the exhaust three-way valve 41 and the air inlet control valve 11 are equipped with an anti-clogging device 13 and a secondary air inlet filter 14. The secondary filter device 14 can perform secondary filtration of the fine powder, preventing materials from entering the Roots blower and the atmosphere, effectively ensuring the cleanliness of the negative pressure vacuum and extending the service life of the equipment. The anti-clogging device 13 has a pressure detection function, which monitors the pressure in the pipeline in real time. When the pressure is too high, it automatically opens the valve to introduce air, ensuring the safe and stable operation of the system.

[0028] In summary, the positive and negative pressure powder conveying system of this embodiment can realize quantitative cyclic conveying of powder, accurately control the powder quality entering the reaction vessel, and simultaneously recycle the conveying gas, effectively reducing energy consumption.

Claims

1. A positive and negative pressure powder conveying system, comprising a Roots blower (1), a buffer tank (2), and a powder feeding device (3), wherein the outlet of the Roots blower (1) is connected to the circulation inlet valve (22) at the inlet of the buffer tank (2) via an exhaust control valve (12), the buffer tank (2) is externally connected to a nitrogen source via an external nitrogen supply inlet valve (21), the outlet of the buffer tank (2) is connected to the inlet of a mixing acceleration chamber (34) via an exhaust valve (23), and the discharge port of the powder feeding device (3) is connected to the inlet of the mixing acceleration chamber (34) via a rotary airlock valve (33), characterized in that: It also includes an integrated filter, a weighing silo, and a reaction vessel (6). The integrated filter is equipped with a filter bag filter, and the weighing silo is equipped with a weighing device. The integrated filter and the weighing silo are installed as a single unit. The outlet of the mixing acceleration chamber (34) is connected to the inlet of the weighing silo, and the outlet of the weighing silo is connected to the reaction vessel (6). The exhaust port of the integrated filter is connected to the inlet of the Roots blower (1) through an air intake control valve (11).

2. The positive and negative pressure powder conveying system according to claim 1, characterized in that: The integrated filter has two units, and the weighing hoppers are correspondingly set in two units; the outlet of the mixing acceleration chamber (34) is connected to the inlet of the feed three-way valve (51), and the two three-way valve outlets of the feed three-way valve (51) are respectively connected to the inlets of the two weighing hoppers; the air extraction ports of the two integrated filter are respectively connected to the two air inlets of the air extraction three-way valve (41), and the air outlet of the air extraction three-way valve (41) is connected to the air intake control valve (11).

3. The positive and negative pressure powder conveying system according to claim 1, characterized in that: The discharge port of the weighing hopper is equipped with a rotary airlock valve.

4. The positive and negative pressure powder conveying system according to claim 3, characterized in that: The weighing hopper is equipped with a venting disc.

5. The positive and negative pressure powder conveying system according to claim 4, characterized in that: The weighing hopper is equipped with a pneumatic hammer.

6. The positive and negative pressure powder conveying system according to claim 1, characterized in that: The exhaust valve (23) is connected to the mixing acceleration chamber (34) via a pipe, on which an intake filter (31) and an intake valve (32) are installed.

7. The positive and negative pressure powder conveying system according to claim 1, characterized in that: The exhaust control valve (12) is connected to the recirculation intake valve (22) via a pipe, on which a condenser (15) and a gas-water separator (16) are installed.

8. A positive and negative pressure powder conveying system according to claim 7, characterized in that: The pipeline is also equipped with an activated carbon filter (17).

9. A positive and negative pressure powder conveying system according to claim 2, characterized in that: The three-way valve (41) is connected to the air intake control valve (11) via a pipe, and the pipe is equipped with an anti-clogging device (13) and a secondary air intake filter (14).

10. A positive and negative pressure powder conveying system according to claim 1, characterized in that: A safety valve (24) is provided at the top of the buffer tank (2).

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