Pellet returned material pneumatic conveying system

Abstract

The utility model discloses a pellet return pneumatic conveying system which comprises two sending pumps, pump bodies are in an inverted cone shape, a feeding dome valve and a discharging dome valve are installed at the top and the bottom of each sending pump, each feeding dome valve is connected with a raw material box, and a T-shaped tee joint is installed at an outlet of each discharging dome valve. T-shaped tee joints at the bottoms of the two sending pumps are connected through pipelines between the pumps, and the two sending pumps are arranged in the front and serve as main pumps, and the other sending pump serves as an auxiliary pump. A T-shaped three-way inlet of the main pump is connected with an outlet of the main pipeline through an air inlet pipeline, and an air inlet valve is installed on the air inlet pipeline. An inlet of the main pipeline is connected with gas conveying equipment, the main pipeline is provided with a main valve, and a T-shaped three-way outlet of the auxiliary pump is connected with a returned material receiving bin through a conveying pipeline. A pressurizing air inlet pipeline is connected between an outlet of the main pipeline and a pressurizing inlet of each sending pump, and a pressurizing switch valve is installed on the pressurizing air inlet pipeline. An air supply pipeline is connected between the outlet of each T-shaped tee joint and the outlet of the main pipeline and is provided with an air supply valve. According to the utility model, the phenomena that the bottom outlet of the sending pump is damaged, settled, accumulated and even blocked are avoided.

Description

TECHNICAL FIELD

[0001] The utility model relates to a pneumatic conveying system, especially a pneumatic conveying system for a pellet production process return material link. BACKGROUND

[0002] The pellet production process is to add a proper amount of water and binder to the fine ore to obtain green pellets with uniform viscosity and certain strength, then to dry, preheat and roast the green pellets to produce pellet ore as a spherical iron-containing raw material (referred to as raw material) for steelmaking and ironmaking processes. With the increasing maturity and rapid development of production technology, the pellet production process adds a raw material screening process. The raw material that is determined to be inconsistent with production requirements needs to be returned for processing. Therefore, the return material link is an important link in the pellet production process.

[0003] The current common return material method is to send the pellet ore that is inconsistent with production requirements to a return material receiving bin through a conveyor or a bucket elevator for secondary processing. However, this mechanical return material method has the defects of dust raising, environmental pollution, high failure rate, manual operation, and high labor cost. Nowadays, the pneumatic conveying system is considered an ideal way for pellet ore return material. However, the pneumatic conveying system for conveying light dust, powder, and other materials is often designed with an arc elbow at the bottom outlet to improve the conveying smoothness and achieve long-distance conveying. However, the composition of the pellet ore is complex, containing blocky material and dust. The blocky material has a large bulk specific gravity and strong abrasiveness. If the above-mentioned pneumatic conveying system is used to convey heavy pellet ore, the arc elbow will be severely worn, and the pellet ore will often settle and accumulate or even block at the pump bottom outlet, resulting in poor conveying and increasing the conveying difficulty. UTILITY MODEL CONTENTS

[0004] The utility model aims at providing a pellet return material pneumatic conveying system, which has the advantages of strong conveying capacity, avoids the damage, settlement and accumulation, or even blockage of the pump bottom outlet.

[0005] In order to achieve the above-mentioned purpose, the utility model adopts the following technical solutions:

[0006] The utility model discloses a kind of pellet return material pneumatic conveying systems, including two sending pumps, the pump body of the sending pump is inverted cone, top inlet, bottom outlet of the sending pump is respectively equipped with feeding dome valve, discharging dome valve, the feeding dome valve is connected with the bottom of raw material box, the outlet of the discharging dome valve is equipped with T type tee, wherein: two the sending pump parallel arrangement, the T type tee between the bottom of each the sending pump is connected via inter-pump pipeline, the sending pump in front as main pump while another the sending pump as auxiliary pump;The inlet of the T type tee of the main pump is connected with main pipeline outlet via air inlet pipeline, air inlet valve is installed on the air inlet pipeline;The inlet of main pipeline is connected with conveying gas equipment, main valve is installed on the main pipeline, the outlet of the T type tee of the auxiliary pump is connected with return material receiving bin via conveying pipeline;The outlet of main pipeline is connected with the pressurized inlet between each the sending pump, pressurized inlet pipeline is installed on the pressurized inlet pipeline;The outlet of each the T type tee is connected with the outlet of main pipeline between supplementary air pipeline, supplementary air valve is installed on the supplementary air pipeline.

[0007] The utility model has the advantages of:

[0008] The utility model is designed for conveying heavy weight pellet, and has strong conveying capacity, can convey pellet smoothly and efficiently, and the whole conveying process is completely closed, without environmental pollution problem, in addition, the bottom outlet part of sending pump is not damaged, not sediment accumulation, even without the problem of plugging, is suitable for promotion. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 It is the component schematic diagram of the utility model pellet return material pneumatic conveying system.

[0010] Figure 2 It is the bottom outlet schematic diagram of sending pump. DETAILED DESCRIPTION

[0011] As Figure 1 And Figure 2The utility model provides a kind of pellet return material pneumatic conveying system, including two sending pumps 10, the pump body of sending pump 10 is inverted conical, the top inlet, bottom outlet of sending pump 10 is equipped with feeding dome valve 11, discharging dome valve 12 respectively, feeding dome valve 11 is connected with the bottom of raw material tank 20 for temporarily storing unqualified raw materials, the outlet of discharging dome valve 12 is equipped with T type tee joint 30, i.e. the feeding port of T type tee joint 30 is connected with the outlet of discharging dome valve 12, wherein: two sending pumps 10 are arranged side by side, and the T type tee joint 30 of each sending pump 10 bottom is connected via inter-pump pipeline 431, and the sending pump 10 in front is arranged as main pump while the other sending pump 10 is arranged as auxiliary pump;The inlet of the T type tee joint 30 of main pump is connected with the outlet of total pipeline 41 via air inlet pipeline 433, and air inlet valve 430 is installed on air inlet pipeline 433;The inlet of total pipeline 41 is connected with conveying gas equipment (not shown in the drawing), and total valve 410 is installed on total pipeline 41, and the outlet of the T type tee joint 30 of auxiliary pump is connected with return material receiving bin (not shown in the drawing) via conveying pipeline 432;The outlet of total pipeline 41 is connected with the pressurized inlet of each sending pump 10, and pressurized inlet pipeline 42 is installed on pressurized inlet pipeline 42;The outlet of each T type tee joint 30 is connected with the outlet of total pipeline 41, and air supplement pipeline 44 is installed on air supplement pipeline 44.

[0012] In the utility model, sending pump 10 is inverted conical, and there is no arc elbow design at the bottom, so that the bottom outlet is not worn and damaged when conveying pellet ore.

[0013] In the utility model, the design of T type tee joint 30 shortens the distance between conveying gas and falling raw materials, so that the raw materials are directly contacted with sufficient gas in a short distance, and the contact position is very close to the outlet of T type tee joint 30, so that the raw materials are quickly sent out in a short time, avoiding the problem that pellet ore, which is not easy to convey, is retained in sending pump 10 for a long time and is deposited or even blocked, reducing the conveying difficulty and ensuring smooth conveying.

[0014] As Figure 2 , the bottom outlet 101 of sending pump 10 is surrounded by two straight edges and two arc edges, and the area of the bottom outlet 101 is equal to the cross-sectional area of the top part of the valve core of the discharging dome valve 12, wherein, when the valve core is closed, the valve core is attached to the bottom outlet 101, and the bottom outlet 101 is sealed. The utility model limits the discharge through the bottom outlet 101, and cooperates with the discharging dome valve 12, so that the discharging dome valve 12 can adjust the opening degree without being limited by the blocking of the falling material, thereby adjusting and controlling the discharge amount and the pressure in the conveying pipeline 432.

[0015] The pressure in the conveying pipeline 432 is generally about 0.2 MPa. When the pressure is greater than this value (i.e. the pipe blocking threshold), there is a risk of pipe blocking. For example, when the pressure in the conveying pipeline 432 is about 0.28 MPa, the outlet dome valve 12 opening can be adjusted to 50%, the conveying gas volume remains unchanged, and then the pressure in the conveying pipeline 432 will decrease to about 0.2 MPa after a certain period of time. When the pressure in the conveying pipeline 432 is about 0.26 MPa, the outlet dome valve 12 opening can be adjusted to 75%, the conveying gas volume remains unchanged, and then the pressure in the conveying pipeline 432 will decrease to about 0.2 MPa after a certain period of time.

[0016] As Figure 1 , a manual plug valve 21 is installed at the bottom opening of the raw material tank 20, which is used for maintenance and is normally open during non-maintenance periods. The manual plug valve 21 is connected to the inlet dome valve 11 through a flexible joint 22.

[0017] As Figure 1 , each sending pump 10 is connected to the corresponding raw material tank 20 through a balance pipeline 60, and a balance valve 61 is installed on the balance pipeline 60. The balance valve 61 is used for venting to make the pressure in the raw material tank 20 consistent with the pressure in the sending pump 10, so that the raw material can fall into the sending pump 10 under its own gravity. The top and bottom of the sending pump 10 are provided with a high-level material level meter 71 and a low-level material level meter 72, which are used to detect the position of the raw material in the pump. When the high-level material level meter 71 sends a signal indicating that the sending pump 10 is full of raw material, and when the low-level material level meter 72 sends a signal indicating that the raw material in the sending pump 10 has been completely sent out. A pump pressure gauge 73 is installed on the sending pump 10 to measure the internal pressure of the sending pump 10. A pipeline pressure gauge 74 is installed on the conveying pipeline 432 to measure the pressure in the conveying pipeline 432.

[0018] As Figure 1 , the air supplement pipeline 44 includes an air supplement main pipeline 440, and the air supplement valve includes a first air supplement valve 444 and a second air supplement valve 443. The inlet of the air supplement main pipeline 440 is connected to the outlet of the main pipeline 41, and the outlet of the air supplement main pipeline 440 is divided into two paths. One path is connected to the outlet of the T-shaped three-way joint 30 at the bottom of the main pump through a first air supplement pipeline 441, and the other path is connected to the outlet of the T-shaped three-way joint 30 at the bottom of the auxiliary pump through a second air supplement pipeline 442. The first air supplement valve 444 is installed on the air supplement main pipeline 440, and the second air supplement valve 443 is installed on the second air supplement pipeline 442.

[0019] In actual implementation, the first air supplement pipeline 441 can be sequentially provided with a throttle orifice plate 51 and a check valve 52. Similarly, the outlet of the second air supplement valve 443 on the second air supplement pipeline 442 can be sequentially provided with a throttle orifice plate 51 and a check valve 52. In addition, the outlet of the air inlet valve 430 on the air inlet pipeline 433 can be sequentially provided with a throttle orifice plate 51 and a check valve 52. Of course, throttle orifice plates and check valves can also be installed on other pipelines as needed.

[0020] In actual implementation, a filter 46 is installed on the main pipeline 41 to ensure that the conveying gas is free of impurities and to avoid affecting the conveying.

[0021] As Figure 1 The pump body of each sending pump 10 is connected with a pressurized air inlet pipeline 42, and a pressurized on-off valve 420 is installed on each pressurized air inlet pipeline 42.

[0022] As Figure 1 The outlet of the air supplement main pipeline 440 is also connected with a boosting pipeline 45, and the boosting pipeline 45 is arranged side by side with the conveying pipeline 432. A plurality of boosting branch pipelines 820 are connected between the boosting pipeline 45 and the conveying pipeline 432. The boosting branch pipelines 820 are arranged in parallel and separated from each other, and a boosting assembly 82 is installed on each boosting branch pipeline 820. Generally, one end of the boosting pipeline 45 is connected with the outlet of the air supplement main pipeline 440, and the other end is closed, which is appropriate.

[0023] In actual design, the boosting assembly 82 includes a throttle orifice plate, and three holes with a diameter of 1.5 mm are formed in the throttle orifice plate to control the amount of air supplied to the boosting pipeline 45 and finely adjust the air supplement amount of the conveying pipeline 432 to ensure smooth conveying.

[0024] The design of the air supplement pipeline 44 and the boosting pipeline 45 can effectively compensate for the pressure reduction in the pipeline to ensure smooth, stable and efficient conveying.

[0025] In actual implementation, if air supplement is needed, the first air supplement valve 444 is first opened to supplement the outlet of the T-shaped three-way pipe 30 at the bottom of the main pump, then the second air supplement valve 443 is opened to continue to supplement the outlet of the T-shaped three-way pipe 30 at the bottom of the auxiliary pump, and then the boosting valve 450 is opened to supply boosting air to the entire conveying pipeline 432, which is conducive to the smooth conveying of raw materials and efficient and reliable operation.

[0026] As Figure 1 The outlet of the T-shaped three-way pipe 30 at the bottom of the auxiliary pump is connected with the raw material tank 20 above the auxiliary pump through a blockage removal pipeline 80, and a blockage removal valve 81 is installed on the blockage removal pipeline 80. The design purpose of the blockage removal pipeline 80 is to return the blocked raw materials in the conveying pipeline 432 to the adjacent raw material tank 20 to dredge the conveying pipeline 432 and ensure smooth conveying.

[0027] In the utility model, the sending pump 10 is a pressure container, the volume of which can be designed as 0.3m 3 -3m 3 , which can realize large capacity and long distance conveying.

[0028] Generally, the conveying gas equipment comprises a conveying gas tank, the gas inlet of the conveying gas tank is connected with a gas source, a gas inlet valve is arranged at the gas inlet, and a safety valve, a pressure regulating valve and a blowdown valve should also be installed on the conveying gas tank, which is a conventional practice and thus is not described here. Nitrogen is usually selected as the conveying gas.

[0029] In the utility model, the throttle orifice plate is used for controlling the gas flow, and the check valve is used for preventing the gas backflow. The total valve 410 is used for controlling the start and stop of the conveying, pressurizing, air supplementing and boosting processes.

[0030] In the utility model, the valves, flexible joints, material level meters, pressure gauges, throttle orifice plates and dome valves are all well-known technologies in the field, and the valves, material level meters, pressure gauges and dome valves are connected with the control device and controlled by the control device. Here, the control device is an existing well-known electronic control device, which is not described in detail.

[0031] In the utility model, the position reached first by the conveying gas is front, and the position reached last is rear.

[0032] During conveying, the main pump and the auxiliary pump are operated alternately.

[0033] When the main pump is operated, the balance valve 61 of the main pump is opened, the feeding dome valve 11 is opened, and the raw materials in the raw material tank 20 above the main pump fall into the main pump under the action of gravity. When the high material level meter 71 on the main pump detects that the raw materials are in place, that is, the main pump is filled with raw materials, the feeding dome valve 11 is closed. The pressurizing on-off valve 420 is opened, and the main pump starts to be pressurized. When the pressure in the main pump is greater than or equal to the pressure in the conveying pipeline 432, the discharge dome valve 12 is opened (the opening degree of the discharge dome valve 12 can be set according to the pressure in the conveying pipeline 432), so that the raw materials fall into the T-shaped tee joint 30 under the action of the pressurized gas, and at the same time, the gas inlet valve 430 is opened, so that the raw materials falling into the T-shaped tee joint 30 are quickly sent out, pass through the inter-pump pipeline 431, the T-shaped tee joint 30 below the auxiliary pump and then enter the conveying pipeline 432, and finally enter the return material receiving bin. During the conveying process, the first air supplementing valve 444, the second air supplementing valve 443 and the boosting valve 450 are also opened at the same time, so that the conveying is smooth and stable. In addition, during the entire conveying process, when the pressure in the conveying pipeline 432 is higher than the pipe blocking threshold value, the opening degree of the discharge dome valve 12 is changed, so that the pressure in the conveying pipeline 432 is reduced to the normal value.

[0034] When the main pump is running, the auxiliary pump is exhausted through the balance valve 61, the material dome valve 11 is filled, and the pressurizing switch valve 420 is pressurized, so that the pump body is filled with raw materials. When the low-level material level meter 72 of the main pump detects that the raw materials are in place, that is, there is no raw material in the pump, the discharge dome valve 12 of the main pump is closed, the exhaust, filling and pressurization are started, and the next conveying cycle is waited to be executed. At this time, the discharge dome valve 12 of the auxiliary pump is opened, and the main pump is replaced to start conveying the raw materials. The conveying process is the same as that of the main pump, and will not be repeated here.

[0035] The utility model has the advantages of:

[0036] The utility model discloses a design for conveying heavy weight pellets, and has strong conveying capacity, can convey the pellets smoothly and efficiently, and has the whole conveying process closed, no environmental pollution problem, in addition, the bottom outlet part of the sending pump has no damage, no settlement accumulation even the problem of blockage, is suitable for promotion.

[0037] The above is the preferred embodiment of the utility model and the technical principle used, for the person skilled in the art, any equivalent transformation, simple replacement and the like based on the technical scheme of the utility model without departing from the spirit and scope of the utility model, all belong to the protection scope of the utility model.

Claims

1. A pellet recycle pneumatic conveying system characterized by, The application relates to a feeding pump device, which comprises two feeding pumps, the pump body of the feeding pump is in the shape of an inverted cone, a feeding dome valve and a discharging dome valve are respectively arranged at the top inlet and the bottom outlet of the feeding pump, the feeding dome valve is connected with the bottom outlet of a raw material box, and the outlet of the discharging dome valve is provided with a T-shaped three-way pipe, wherein the two feeding pumps are arranged side by side, the T-shaped three-way pipes at the bottom of the feeding pumps are connected through an inter-pump pipeline, the feeding pump arranged in front is used as a main pump, and the other feeding pump is used as a sub-pump; the inlet of the T-shaped three-way pipe of the main pump is connected with the outlet of a total pipeline through an air inlet pipeline, and an air inlet valve is arranged on the air inlet pipeline; the inlet of the total pipeline is connected with a conveying gas device, a total valve is arranged on the total pipeline, and the outlet of the T-shaped three-way pipe of the sub-pump is connected with a return material receiving bin through a conveying pipeline; a pressurized air inlet pipeline is arranged between the outlet of the total pipeline and the pressurized inlets of the feeding pumps, and a pressurized switch valve is arranged on the pressurized air inlet pipeline; a gas supplement pipeline is arranged between the outlet of each T-shaped three-way pipe and the outlet of the total pipeline, and a gas supplement valve is arranged on the gas supplement pipeline.

2. A pellet recycle pneumatic conveying system as claimed in claim 1 wherein, The bottom outlet of the feeding pump is surrounded by two straight edges and two arc-shaped edges, the area of the bottom outlet is equal to the sectional area of the top part of the valve core of the discharging dome valve, and when the valve core is closed, the valve core is in close contact with the bottom outlet to seal the bottom outlet.

3. A pellet recycle pneumatic conveying system as claimed in claim 1 wherein, A manual plug valve is arranged at the bottom outlet of the raw material box, and the manual plug valve is connected with the feeding dome valve through a flexible joint.

4. A pellet recycle pneumatic conveying system as claimed in claim 1 wherein, A balance pipeline is arranged between each feeding pump and the corresponding raw material box, and a balance valve is arranged on the balance pipeline, wherein high-level material level gauges and low-level material level gauges are arranged at the top and bottom of the feeding pump, a pump pressure gauge is arranged on the feeding pump, and a pipeline pressure gauge is arranged on the conveying pipeline.

5. A pellet recycle pneumatic conveying system as claimed in claim 1 wherein, The gas supplement pipeline comprises a gas supplement total pipeline, the gas supplement valve comprises a first gas supplement valve and a second gas supplement valve, the inlet of the gas supplement total pipeline is connected with the outlet of the total pipeline, the outlet of the gas supplement total pipeline is divided into two paths, one path is connected with the outlet of the T-shaped three-way pipe at the bottom of the main pump through a first gas supplement pipeline, the other path is connected with the outlet of the T-shaped three-way pipe at the bottom of the sub-pump through a second gas supplement pipeline, the first gas supplement valve is arranged on the gas supplement total pipeline, and the second gas supplement valve is arranged on the second gas supplement pipeline.

6. A pellet recycle pneumatic conveying system as claimed in claim 5 wherein, The outlet of the gas supplement total pipeline is also connected with a boosting pipeline, the boosting pipeline is arranged side by side with the conveying pipeline, a plurality of boosting branch pipelines are arranged between the boosting pipeline and the conveying pipeline, the boosting branch pipelines are arranged separately side by side, and a boosting assembly is arranged on each boosting branch pipeline.

7. A pellet recycle pneumatic conveying system as claimed in claim 6 wherein, The boosting assembly comprises a throttle orifice plate, and three holes with a diameter of 1.5 mm are arranged on the throttle orifice plate.

8. A pellet recycle pneumatic conveying system as claimed in claim 6 wherein, The outlet of the T-shaped three-way pipe at the bottom of the sub-pump is connected with the raw material box above the sub-pump through a blockage discharging pipeline, and a blockage discharging valve is arranged on the blockage discharging pipeline.

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