A dense phase conveying system and process operating under varying loads

Abstract

The application discloses a dense phase conveying system and process under variable load. The system comprises a conveying pipeline for gas and material conveying, and a gas buffer unit, a gas on-off unit, a gas pressure reduction unit, a gas filter unit, a gas control unit A, a rotary discharge valve and a reversing valve which are sequentially connected in the conveying pipeline. The system further comprises a gas control unit B which is connected in the conveying pipeline and is in parallel with the gas control unit A. The material for dense phase conveying is adjusted in its discharge capacity by the rotary discharge valve and then enters the conveying pipeline. The material for dense phase conveying is conveyed to different bins by the reversing valve. The dense phase conveying process of the application is a process for automatically adjusting the gas inlet quantity at one or more points according to the conveying capacity, and can obviously improve the dense phase conveying process within a certain variable load range.

Description

Technical Field

[0001] This invention relates to the field of dense phase conveying technology, specifically to a dense phase conveying system and process for variable load operation. Background Technology

[0002] Dense phase conveying is characterized by a small conveying volume and a relatively large conveying pressure drop. It is suitable for pneumatic conveying of fragile materials or high-priced bulk products.

[0003] Dense phase pneumatic conveying system design typically assumes maximum production capacity, meaning the system is designed for full-load operation. However, in reality, system load varies, and low-load (low-capacity) situations frequently occur. Because the production load is lower in these situations, and the system is designed for full load, the conveying gas volume is generally a constant volume at full load. However, at low loads, the material conveying rate decreases significantly. To ensure stable material conveying at low loads, a device to reduce the gas supply needs to be installed in the upstream pipeline. But since the conveying system provides a constant gas volume, the gas velocity at the initial stage downstream of the material conveyor inevitably increases significantly after passing through this device. This faster airflow causes material abrasion, resulting in material loss and affecting the quality of the final product. Summary of the Invention

[0004] The purpose of this invention is to address the problem that existing dense phase conveying systems are prone to material wear and tear and affect the quality of the final product when operating under low load. This invention designs a dense phase conveying system that operates under variable load, effectively solving the above-mentioned problems.

[0005] To solve the above problems, the present invention is achieved through the following technical solution:

[0006] This invention designs a dense phase conveying system for variable load operation. The dense phase conveying system includes: a conveying pipeline for conveying gas and materials, and a gas buffer unit, a gas on / off unit, a gas pressure reducing unit, a gas filtering unit, a gas control unit A, a rotary discharge valve, and a reversing valve that are sequentially connected to the conveying pipeline.

[0007] The dense phase delivery system also includes a gas control unit B connected to the delivery pipeline, and the gas control unit B is connected in parallel with the gas control unit A;

[0008] The material conveyed in the dense phase is fed into the conveying pipeline after its discharge capacity is adjusted by the rotary discharge valve; the material conveyed in the dense phase is then conveyed to different silos by the reversing valve.

[0009] Furthermore, in a dense-phase conveying system operating under variable load, the gas on / off unit is configured as a pneumatic butterfly valve.

[0010] Furthermore, a dense phase conveying system operating under variable load: the gas for dense phase conveying is conveyed via the conveying pipeline to the gas buffer unit for stabilization.

[0011] Furthermore, a dense phase conveying system operating under variable load: the air inlet of the gas control unit B is located downstream of the gas filter unit and upstream of the rotary feed valve, and its air outlet is located downstream of the rotary feed valve and upstream of the reversing valve.

[0012] Furthermore, a dense phase conveying system operating under variable load: the dense phase conveying system further includes: a pressure sensor installed on the conveying pipeline, wherein the pressure sensor is installed downstream of the gas control unit A and upstream of the rotary feed valve, and the pressure sensor is linked to the rotary feed valve.

[0013] A dense-phase conveying process for variable load operation is provided. This process employs the aforementioned dense-phase conveying system for variable load operation, and includes the following steps:

[0014] S1. The gas source is delivered to the gas buffer unit through the delivery pipeline to stabilize the gas flow.

[0015] S2. Open the gas on / off unit so that the gas in the gas buffer unit passes through the gas depressurization unit for depressurization and the gas filtration unit for impurity removal, and then enters the gas control unit B and / or gas control unit A.

[0016] S3. The material to be conveyed in the dense phase enters the conveying pipeline after being regulated by the rotary feed valve;

[0017] When conveying materials with high production capacity: gas control unit A is turned on and gas control unit B is turned off at the same time. The material feeding capacity is increased by adjusting the rotary feed valve. When conveying materials with low production capacity: gas control unit A is turned on and gas control unit B is turned on at the same time. The material feeding capacity is decreased by adjusting the rotary feed valve, thus completing the dense phase conveying of materials.

[0018] The beneficial effects of this invention are:

[0019] (1) The variable load operation dense phase conveying system designed in this invention, through the setting of gas control unit A and gas control unit B, can ensure the stable material conveying speed and prevent material wear, regardless of whether the material is conveyed at high or low production capacity. By optimizing the position of gas control unit B, this invention can significantly improve the speed of dense phase conveying under different load conditions of the entire conveying line, prevent material wear, and thus meet the product quality requirements of dense phase conveying under different load conditions, while also reducing gas consumption at low loads.

[0020] (2) The dense phase conveying process provided by the present invention is a dense phase conveying process that automatically adjusts the air intake at one or more points according to the conveying capacity, which can significantly improve the dense phase conveying process within a certain range of load variation. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of a dense-phase conveying system with variable load operation designed according to Embodiment 1 of the present invention;

[0023] Figure 2 This is a schematic diagram of a dense phase conveying system designed according to Embodiment 2 of the present invention.

[0024] The markings in the diagram are: 1-Gas buffer unit, 2-Gas on / off unit, 3-Gas pressure reducing unit, 4-Gas filter unit, 5-Gas control unit A, 6-Rotary discharge valve, 7-Reversing valve, 8-Gas control unit B, 9-Conveying pipeline, 10-Hopper, 11-Pressure sensor. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0026] In the description of this invention, it should be understood that the terms "upper," "lower," "left," "right," "top," and "bottom," etc., indicating orientation or positional relationships, are merely for the convenience of describing the 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, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" and "second" may explicitly or implicitly include one or more of that feature. Moreover, the terms "first," "second," etc., are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein.

[0027] Example 1

[0028] like Figure 1 As shown, a dense phase conveying system with variable load operation is designed. The dense phase conveying system includes: a conveying pipeline 9 for conveying gas and materials, and a gas buffer unit 1 (gas buffer tank), a gas on / off unit 2 (pneumatic butterfly valve), a gas pressure reducing unit 3 (pressure reducing valve), a gas filtering unit 4 (filter), a gas control unit A 5, a rotary discharge valve 6, and a reversing valve 7, which are sequentially connected to the conveying pipeline 9; the gas used for dense phase conveying is conveyed through the conveying pipeline 9 to the gas buffer unit 1 to stabilize the gas;

[0029] The dense phase conveying system also includes a gas control unit B8 connected to the conveying pipeline 9, and the gas control unit B8 is connected in parallel with the gas control unit A5; specifically, the air inlet of the gas control unit B8 is located downstream of the gas filter unit 4 and upstream of the rotary feed valve 6, and its air outlet is located downstream of the rotary feed valve 6 and upstream of the reversing valve 7; the dense phase conveying system also includes a pressure sensor 11 installed on the conveying pipeline 9, and the pressure sensor 11 is located downstream of the gas control unit A5 and upstream of the rotary feed valve 6, and the pressure sensor 11 is linked to the rotary feed valve 6;

[0030] The material being conveyed in the dense phase is fed into the conveying pipeline 9 after its discharge capacity is adjusted by the rotary discharge valve 6; the material being conveyed in the dense phase is then transported to different silos 10 via the reversing valve 7. The gas control unit B 8 and the gas control unit A 5 can adjust the conveying gas volume.

[0031] A dense-phase conveying process for variable load operation is provided, which adopts a dense-phase conveying system for variable load operation designed in Example 1. The process includes the following specific steps:

[0032] S1. External gas (gas source) is transported to the gas buffer unit 1 through the conveying pipeline 9 to stabilize the gas and facilitate the subsequent material conveying.

[0033] S2. Turn on the gas on / off unit 2 so that the gas passes through the gas buffer unit 1 in sequence through the gas pressure reducing unit 3 for pressure reduction, and then through the gas filter unit 4 for impurity removal. After impurity removal, the gas is ready for the next step of use.

[0034] S3. The material to be conveyed in the dense phase is regulated by the rotary feed valve 6 and then enters the conveying pipeline 9.

[0035] ① When conveying materials with high production capacity: turn on the gas control unit A5 and increase the conveying gas volume of the gas control unit A5, while turning off the gas control unit B8. The conveying pressure is detected by the pressure sensor 11. The pressure sensor 11 is linked with the rotary discharge valve 6, thereby adjusting the rotary discharge valve 6 to increase the material discharge capacity.

[0036] ② When conveying materials with small production capacity: turn on the gas control unit A 5 and the gas control unit B 8 at the same time. The conveying pressure is detected by the pressure sensor 11. The pressure sensor 11 is linked with the rotary discharge valve 6, thereby adjusting the rotary discharge valve 6 to reduce the material discharge capacity and complete the dense phase conveying of the material.

[0037] In this invention, a gas control unit B8 is designed in a dense phase conveying system operating under variable load, so that when conveying materials with small production capacity, the constant gas volume in the system can be diverted, thereby preventing the flow rate at the beginning of the material conveying section from being too fast and thus avoiding the problem of material wear.

[0038] Example 2

[0039] like Figure 2 As shown, a dense phase conveying system is designed. The system includes: a conveying pipeline 9 for conveying gas and materials, and a gas buffer unit 1 (gas buffer tank), a gas on / off unit 2 (pneumatic butterfly valve), a gas pressure reducing unit 3 (pressure reducing valve), a gas filtering unit 4 (filter), a gas control unit A 5, a rotary discharge valve 6, and a reversing valve 7, which are sequentially connected to the conveying pipeline 9; the gas for dense phase conveying is conveyed through the conveying pipeline 9 to the gas buffer unit 1 to stabilize the gas;

[0040] The dense phase conveying system also includes a pressure sensor 11 installed on the conveying pipeline 9, and the pressure sensor 11 is installed downstream of the gas control unit A 5 and upstream of the rotary feed valve 6, and the pressure sensor 11 is linked to the rotary feed valve 6.

[0041] The material conveyed by the dense phase is fed into the conveying pipeline 9 after its feeding capacity is adjusted by the rotary feeding valve 6; the material conveyed by the dense phase is conveyed to different silos 10 by the reversing valve 7.

[0042] The main difference between Example 2 and Example 1 is that the gas control unit B8 is not designed in the dense phase transport system designed in Example 2, but the rest are the same.

[0043] A dense phase conveying process is provided, which adopts a dense phase conveying system designed in Embodiment 2 above. The process includes the following specific steps:

[0044] S1. External gas (gas source) is transported to the gas buffer unit 1 through the conveying pipeline 9 to stabilize the gas and facilitate the subsequent material conveying.

[0045] S2. Turn on the gas on / off unit 2 so that the gas passes through the gas buffer unit 1 in sequence through the gas pressure reducing unit 3 for pressure reduction, and then through the gas filter unit 4 for impurity removal. After impurity removal, the gas is ready for the next step of use.

[0046] S3. The material to be conveyed in the dense phase is regulated by the rotary feed valve 6 and then enters the conveying pipeline 9.

[0047] ① When conveying materials with high production capacity: turn on the gas control unit A5 and increase the conveying gas volume of the gas control unit A5. The conveying pressure is detected by the pressure sensor 11. The pressure sensor 11 is linked with the rotary discharge valve 6, thereby adjusting the rotary discharge valve 6 to increase the material discharge capacity.

[0048] ② When conveying materials with small production capacity: turn on the gas control unit A5 and reduce the conveying gas volume of the gas control unit A5 accordingly. The conveying pressure is detected by the pressure sensor 11. The pressure sensor 11 is linked with the rotary discharge valve 6, thereby adjusting the rotary discharge valve 6 to reduce the material discharge capacity and complete the dense phase conveying of the material.

[0049] In the dense phase conveying process using the dense phase conveying systems of Examples 1 and 2 described above:

[0050] ① When conveying materials with large production capacity: There is no significant difference between the dense phase conveying system of Example 2 and the dense phase conveying system of Example 1 with variable load operation;

[0051] ② When conveying materials at a small production capacity: Since the dense phase conveying system in Example 2 does not include a gas control unit B8, it needs to reduce the gas supply outlet of gas control unit A5 to decrease the conveying gas volume. However, since the external gas supply is constant, the airflow velocity at the outlet will increase significantly after passing through gas control unit A5. This will significantly increase the gas velocity at the beginning of the material flow, thus significantly increasing the material conveying speed and exacerbating material wear. In Example 1, by designing gas control unit A5, the gas can be diverted, reducing the gas supply without causing the material to be conveyed too quickly at the beginning. If the conveying gas volume used for a large production capacity is still used when conveying materials at a small production capacity (i.e., without reducing the conveying gas volume through gas control unit A), the reduced material volume will still result in a faster conveying speed at the beginning of the material flow, leading to the same material wear problem.

[0052] ③ For example, the initial design of the conveying system is a conveying gas volume of 850 Nm³. 3 / h, when conveying materials at small production capacity, without making other design changes, simply reduce the initial conveying air volume to 650Nm 3 However, according to the applicant's actual tests, this still leads to a significant increase in the initial conveying speed of the material, resulting in increased wear on the material, more dust or stringing, and adjusting the initial conveying gas volume is relatively troublesome and costly. This application, without changing the initial conveying gas volume, through the design of gas control unit A and gas control unit B, can significantly improve the speed of dense phase conveying in the entire conveying pipeline under different load conditions, thereby meeting the product quality requirements of dense phase conveying under different load conditions.

[0053] The dense phase conveying system designed in this application with variable load operation can flexibly adjust the gas control unit B and coordinate it with the gas control unit A, and can be applied to the dense phase conveying of materials under various load conditions.

[0054] The above-described preferred embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of the invention. Any obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A dense-phase conveying system for variable load operation, characterized in that, The dense phase conveying system includes: a conveying pipeline (9) for conveying gas and materials, and a gas buffer unit (1), a gas on / off unit (2), a gas pressure reducing unit (3), a gas filtering unit (4), a gas control unit A (5), a rotary feed valve (6), and a reversing valve (7) sequentially connected to the conveying pipeline (9). The dense phase conveying system also includes a gas control unit B (8) connected to the conveying pipeline (9), and the gas control unit B (8) and the gas control unit A (5) are connected in parallel; the material conveyed by the dense phase is fed into the conveying pipeline (9) after the discharge capacity is adjusted by the rotary discharge valve (6); the material conveyed by the dense phase is conveyed to different silos (10) by the reversing valve (7); The dense-phase conveying process for variable load operation includes the following steps: S1. The gas source is transported to the gas buffer unit (1) through the delivery pipeline (9) to make the gas stable; S2. Open the gas on / off unit (2) so that the gas passes through the gas pressure reducing unit (3) for pressure reduction and through the gas filtration unit (4) for impurity removal, and then enters the gas control unit B (8) and / or the gas control unit A (5); S3. The material to be conveyed in the dense phase enters the conveying pipeline (9) after being regulated by the rotary feed valve (6); When conveying materials with high production capacity: turn on the gas control unit A (5) and turn off the gas control unit B (8) at the same time, and adjust the material feeding capacity by means of the rotary feeding valve (6); When conveying materials with small production capacity: turn on the gas control unit A (5) and turn on the gas control unit B (8) at the same time. Adjust the material feeding capacity by the rotary feeding valve (6) to complete the dense phase conveying of the material.

2. The dense-phase conveying system for variable load operation according to claim 1, characterized in that, The gas on / off unit (2) is configured as a pneumatic butterfly valve.

3. A dense-phase conveying system for variable load operation according to claim 1, characterized in that, The gas used for dense phase transport is transported through the transport pipeline (9) to the gas buffer unit (1) for stabilization.

4. A dense-phase conveying system for variable load operation according to claim 1, characterized in that, The gas control unit B (8) has its air inlet located downstream of the gas filter unit (4) and upstream of the rotary feed valve (6), and its air outlet located downstream of the rotary feed valve (6) and upstream of the reversing valve (7).

5. A dense-phase conveying system for variable load operation according to claim 1, characterized in that, The dense phase conveying system also includes a pressure sensor (11) installed on the conveying pipeline (9), and the pressure sensor (11) is installed downstream of the gas control unit A (5) and upstream of the rotary feed valve (6), and the pressure sensor (11) is linked to the rotary feed valve (6).

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