Combustible liquid long-distance pipeline delivery pump protection system

Abstract

The utility model discloses a combustible liquid long-distance pipeline delivery pump protection system, which belongs to the field of combustible liquid long-distance pipeline delivery equipment and comprises an upstream pump, a delivery pipeline, a reducing pipe, a pump inlet pipeline, a combustible liquid delivery pump, a pump outlet pipeline and a control system. An outlet of the upstream pump communicates with the conveying pipeline and is used for pressurizing the combustible liquid in the cabin and then conveying the pressurized combustible liquid to the conveying pipeline; a flow meter is arranged on the conveying pipeline; the pipe diameter of the conveying pipeline is smaller than that of the pump inlet pipeline, and the conveying pipeline and the pump inlet pipeline are communicated through reducing pipes with different pipe diameters at the two ends. The pump inlet pipeline is communicated with an inlet of the combustible liquid conveying pump; an outlet of the combustible liquid conveying pump is communicated with a pump outlet pipeline; a regulating valve is further arranged on the pump outlet pipeline; and the flow meter, the combustible liquid conveying pump and the regulating valve are electrically connected with the control system respectively. According to the utility model, the buffer effect can be achieved without arranging a buffer tank, and the delivery pump can be shut down in time to avoid cavitation.

Description

Technical Field

[0001] The utility model belongs to the field of long-distance pipeline transportation equipment for flammable liquids, in particular to a long-distance pipeline transportation pump protection system for flammable liquids. Background Art

[0002] In industrial production, flammable liquids and liquefied hydrocarbons, as important process media, require long-distance transportation via pipelines to meet supply needs. However, due to the length of the pipelines, a transfer pump must be installed in the pipeline to provide relay pressure boosting to ensure that the materials meet the transportation conditions and are smoothly delivered to the destination.

[0003] Since these process media usually have a high saturated vapor pressure, cavitation is prone to occur during the current long-distance transportation process. Cavitation not only affects the stable operation and transportation efficiency of the delivery pump, but also causes corrosion damage on the metal surface in contact with the flammable liquid, affecting the service life of the equipment.

[0004] In order to prevent cavitation in pumps when transporting flammable liquids over long distances, current methods are to improve existing conveying equipment, add buffer tanks in the middle of the pipeline, and add additional conveying pumps to relay and pressurize the materials, ensuring that the goods can be stably transported to downstream users. However, if additional buffer tanks are installed, it involves the configuration of storage tanks, tank foundations, tank instruments, valves, etc., which increases investment. When the volume of the buffer tank for flammable liquids or liquefied hydrocarbons exceeds a certain amount, it is considered a major hazard source, and the project construction approval procedure is complicated. However, if buffer tanks are not installed, it is impossible to provide operators with sufficient reaction time in an emergency so that the staff can shut down the conveying pump in time. In addition, there is energy loss and material loss when flammable liquids enter and exit the buffer tank. In addition, buffer tanks usually need to be installed in the pipe corridor between different devices, which makes it difficult to meet the safety distance requirements between other facilities. Therefore, there is an urgent need to provide a conveying pump protection system that can solve the above problems. Utility Model Content

[0005] The purpose of this utility model is to provide a long-distance flammable liquid pipeline pump protection system to address the above-mentioned shortcomings, and to solve the problem of how to prevent cavitation in the delivery pump system without a buffer tank. To achieve the above-mentioned purpose, the utility model provides the following technical solutions:

[0006] A long-distance pipeline conveying pump protection system for flammable liquids comprises an upstream pump, a conveying pipeline, a reducer, a pump inlet pipeline, a flammable liquid conveying pump, a pump outlet pipeline and a control system; the upstream pump outlet is connected to the conveying pipeline, and is used to pressurize the flammable liquid in the cabin and convey it to the conveying pipeline; a flow meter is provided on the conveying pipeline; the diameter of the conveying pipeline is smaller than that of the pump inlet pipeline, and the conveying pipeline and the pump inlet pipeline are connected through a reducer with different diameters at both ends; the pump inlet pipeline is connected to the inlet of the flammable liquid conveying pump; the outlet of the flammable liquid conveying pump is connected to the pump outlet pipeline; a regulating valve is also provided on the pump outlet pipeline; the flow meter, flammable liquid conveying pump and regulating valve are respectively electrically connected to the control system.

[0007] Furthermore, the pump inlet pipeline includes a first conveying section, a second conveying section, a third conveying section and a fourth conveying section that are connected in sequence; the first conveying section extends vertically upward, the second conveying section extends horizontally toward the direction close to the flammable liquid conveying pump, the third conveying section extends vertically downward, and the fourth conveying section continues to extend horizontally toward the direction close to the flammable liquid conveying pump; the reducer is connected to the first conveying section; the fourth conveying section is connected to the inlet of the flammable liquid conveying pump.

[0008] Furthermore, the height of the conveying pipeline is lower than the height of the second conveying section.

[0009] Furthermore, the first conveying section is also connected to a first liquid level gauge and a pressure gauge; the first liquid level gauge and the pressure gauge are electrically connected to the control system respectively.

[0010] Furthermore, the combustible liquid delivery pump is provided with a second liquid level gauge; the second liquid level gauge is electrically connected to the control system.

[0011] Furthermore, the diameter of the reducer at the outlet is 1.5-2 times the diameter of the reducer at the inlet.

[0012] Furthermore, the flammable liquid delivery pump is a centrifugal pump.

[0013] Furthermore, the flammable liquid delivery pump is a barrel bag pump.

[0014] The beneficial effects of the utility model are:

[0015] The utility model discloses a long-distance pipeline conveying pump protection system for flammable liquids, belonging to the field of long-distance pipeline conveying equipment for flammable liquids. The system comprises an upstream pump, a conveying pipeline, a reducer, a pump inlet pipeline, a flammable liquid conveying pump, a pump outlet pipeline, and a control system. The upstream pump outlet is connected to the conveying pipeline and is used to pressurize the flammable liquid in the cabin and convey it to the conveying pipeline. A flow meter is provided on the conveying pipeline. The diameter of the conveying pipeline is smaller than that of the pump inlet pipeline, and the conveying pipeline and the pump inlet pipeline are connected via reducers with different diameters at both ends. The pump inlet pipeline is connected to the inlet of the flammable liquid conveying pump. The outlet of the flammable liquid conveying pump is connected to the pump outlet pipeline. A regulating valve is also provided on the pump outlet pipeline. The flow meter, the flammable liquid conveying pump, and the regulating valve are each electrically connected to the control system. The utility model can play a buffering role without the need for a buffer tank and can shut down the conveying pump in a timely manner to avoid cavitation. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the process of pipeline transportation of flammable liquids in the present utility model;

[0017] In the attached figure: 1. upstream pump; 2. flow meter; 3. delivery pipeline; 4. reducer; 5. first liquid level gauge; 6. pressure gauge; 7. pump inlet pipeline; 8. flammable liquid delivery pump; 9. regulating valve; 10. pump outlet pipeline; 11. second liquid level gauge. DETAILED DESCRIPTION

[0018] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods, but the present invention is not limited to the following embodiments.

[0019] Example 1:

[0020] See attached Figure 1A flammable liquid long-distance pipeline transportation pump protection system includes an upstream pump 1, a delivery pipeline 3, a reducer 4, a pump inlet pipeline 7, a flammable liquid delivery pump 8, a pump outlet pipeline 10 and a control system; the outlet of the upstream pump 1 is connected to the delivery pipeline 3, and is used to pressurize the flammable liquid in the cabin and deliver it to the delivery pipeline 3; the delivery pipeline 3 is provided with a flow meter 2; the diameter of the delivery pipeline 3 is smaller than the diameter of the pump inlet pipeline 7, and the delivery pipeline 3 and the pump inlet pipeline 7 are connected through a reducer 4 with different diameters at both ends; the pump inlet pipeline 7 is connected to the inlet of the flammable liquid delivery pump 8; the outlet of the flammable liquid delivery pump 8 is connected to the pump outlet pipeline 10; the pump outlet pipeline 10 is also provided with a regulating valve 9; the flow meter 2, the flammable liquid delivery pump 8 and the regulating valve 9 are respectively electrically connected to the control system. As can be seen from the above structure, when the flammable liquid is unloaded, the flammable liquid will be transported through the delivery pump system via the upstream pump 1 in the direction of the delivery pipeline 3, the reducer 4, the pump inlet pipeline 7, the flammable liquid delivery pump 8, and the pump outlet pipeline 10, and finally the flammable liquid will be delivered to the target location. For example, the protection system of the present invention can be applied to the delivery scenarios of long-distance liquid pipelines such as flammable liquid storage areas, liquefied hydrocarbon low-temperature / normal-temperature storage areas for loading and unloading ships, and inter-factory pipelines. The inlet end of the upstream pump 1 is connected to the upstream, that is, the storage device for storing flammable liquids. When it is necessary to transport the flammable liquid to the target tank area, the upstream pump 1 is first used to pressurize the flammable liquid, and the pressurized flammable liquid is output to the delivery pipeline 3 through the upstream pump 1. Specifically, the delivery pipeline 3 extends in the horizontal direction, and the outlet of the delivery pipeline 3 is connected to the inlet of the reducer 4, and the outlet of the reducer 4 is connected to the inlet of the pump inlet pipeline 7. The diameter of the delivery pipeline 3 is smaller than the diameter of the pump inlet pipeline 7, so the reducer 4 can be specifically configured as a trumpet-shaped pipe with a gradually increasing diameter along the delivery direction, so that the reducer 4 can achieve the expansion of the flammable liquid transport pipeline, thereby making the inlet and outlet ends of the reducer 4 match the dimensions of the delivery pipeline 3 and the pump inlet pipeline 7, respectively. The diameter of the pump inlet pipeline 7 is larger than the diameter of the delivery pipeline 3, and the diameter and length of the pump inlet pipeline 7 are set according to actual transportation needs. The utility model increases the volume of the flammable liquid in this part by designing the diameter and length of the pump inlet pipeline 7, and can provide sufficient buffer space for the flammable liquid without setting a buffer tank. After passing through the pump inlet pipeline 7, the flammable liquid is relay-pressurized by the flammable liquid delivery pump 8, and then the secondary pressurized flammable liquid is transported to the tank area through the pump outlet pipeline 10. Since the pump inlet pipeline 7 forms sufficient buffer space and has sufficient capacity, it can provide the operator with reaction time in an emergency situation, so that the operator can shut down the flammable liquid delivery pump 8 in time through the control system to avoid cavitation of the flammable liquid delivery pump 8.A flow meter 2 is provided on the delivery pipeline 3, which can monitor the flow rate of the flammable liquid passing through the delivery pipeline 3 in real time. A regulating valve 9 is also provided on the pump outlet pipeline 10, which can control the opening and closing of the regulating valve 9 to control the transport volume of the flammable liquid. The flow meter 2, the flammable liquid delivery pump 8, and the regulating valve 9 are all electrically connected to a control system to form a control circuit. The flow meter 2, the flammable liquid delivery pump 8, and the regulating valve 9 can be connected to the control system via a wired or wireless connection. During the transport of the flammable liquid, the control system can receive the flow rate signal transmitted by the flow meter 2 in real time and then promptly control the start and stop of the flammable liquid delivery pump 8 and the opening and closing of the regulating valve 9 based on the current flow rate, thereby controlling the transport volume of the flammable liquid. By improving the delivery pipeline, the utility model provides sufficient buffer volume for the flammable liquid, allowing the delivery pump system to function as a buffer without the need for a buffer tank. The pump speed and start and stop of the flammable liquid delivery pump 8 can also be promptly controlled to prevent cavitation.

[0021] Example 2:

[0022] See attached Figure 1 . On the basis of embodiment one, the pump inlet pipeline 7 includes a first conveying section, a second conveying section, a third conveying section and a fourth conveying section that are connected in sequence; the first conveying section extends vertically upward, the second conveying section extends horizontally toward the direction close to the flammable liquid conveying pump 8, the third conveying section extends vertically downward, and the fourth conveying section continues to extend horizontally toward the direction close to the flammable liquid conveying pump 8; the reducer 4 is connected to the first conveying section; the fourth conveying section is connected to the inlet of the flammable liquid conveying pump 8. It can be seen from the above structure that the pump inlet pipeline 7 includes a first conveying section, a second conveying section, a third conveying section and a fourth conveying section that are connected in sequence, and the pipe diameters of the first conveying section, the second conveying section, the third conveying section and the fourth conveying section can be set to be the same or different according to needs. According to the attached Figure 1 In the arrangement shown, the flammable liquid in the pump inlet pipeline 7 can be first vertically transported upward through the first transport section, then transported to the right through the second transport section, then transported downward through the third transport section, and finally transported to the right through the fourth transport section to the flammable liquid delivery pump 8. The length and diameter of the fourth delivery section can be adaptively set according to the position of the flammable liquid delivery pump 8 to ensure a stable and reliable connection with the flammable liquid delivery pump 8. Since the ground equipment may conflict or affect the pipeline layout during the transportation process on land after unloading, a part of the pump inlet pipeline 7 is folded upward to avoid the ground equipment. The specific length and height of the upward part of the pump inlet pipeline 7 can be adaptively adjusted according to the actual pipeline corridor structure to make the delivery pump system adapt to the terrain and maintain the continuity and stability of the transportation. In addition, the reducer 4 can also be set vertically and connected to the bottom of the first delivery section.

[0023] The height of the delivery pipeline 3 is lower than that of the second delivery section. As can be seen from the above structure, the height of the delivery pipeline 3 is set to be lower than that of the second delivery section to adapt to the pipe gallery structure.

[0024] The first delivery section is also connected to a first liquid level gauge 5 and a pressure gauge 6; the first liquid level gauge 5 and the pressure gauge 6 are electrically connected to the control system respectively. As can be seen from the above structure, by setting the first liquid level gauge 5 and the pressure gauge 6, the liquid level and hydraulic pressure of the flammable liquid can be monitored in real time, and the liquid level signal and the hydraulic pressure signal are transmitted to the terminal in real time through the control system, so that the operator can obtain the real-time changes of the pump inlet pipeline pressure and liquid level. Specifically, the first liquid level gauge 5 can be set at the top of the first delivery section. When the flammable liquid is not full in the pipe or the pressure is lower than the preset lower limit, the control system controls the flammable liquid delivery pump 8 to stop delivery to protect the delivery pump from cavitation. An alarm can also be added. When the flammable liquid delivery pump 8 is shut down, the alarm emits an audible, optical or other form of alarm to notify the operator to make adjustments in time.

[0025] The flammable liquid delivery pump 8 is provided with a second liquid level gauge 11; the second liquid level gauge 11 is electrically connected to the control system. As can be seen from the above structure, the operator can also monitor the liquid level of the flammable liquid delivery pump 8 in real time through the second liquid level gauge 11. If an abnormality is found, the operator can promptly adjust the pumping speed of the flammable liquid delivery pump 8 to restore the flammable liquid delivery to normal. If normalization is not possible, the operator can directly shut down the flammable liquid delivery pump 8 to prevent cavitation.

[0026] Example 3:

[0027] See attached Figure 1 Based on the second embodiment, the diameter of the reducer 4 at the outlet is 1.5-2 times the diameter of the reducer 4 at the inlet. As can be seen from the above structure, the diameter of the reducer 4 at the outlet matches the diameter of the pump inlet pipeline 7, and the diameter of the reducer 4 at the inlet matches the diameter of the delivery pipeline 3. The diameter of the reducer 4 at the outlet is 1.5-2 times the diameter of the reducer 4 at the inlet to meet the setting requirements of the pump inlet pipeline 7.

[0028] The flammable liquid delivery pump 8 is a centrifugal pump or a barrel pump. As can be seen from the above structure, the selection of the flammable liquid delivery pump 8 is based on the type of liquid to be delivered and the construction conditions of the delivery pump system. For example, for the delivery of media with high saturated vapor pressure, especially liquefied hydrocarbons and liquid ammonia, a barrel pump is used. For situations where it is inconvenient to bury the pump body underground, the construction is difficult, and the flammable liquid delivery conditions are not harsh, a centrifugal pump can be selected.

[0029] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of the present invention, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A long-distance flammable liquid pipeline pump protection system, characterized by: The invention comprises an upstream pump (1), a delivery pipeline (3), a reducer (4), a pump inlet pipeline (7), a flammable liquid delivery pump (8), a pump outlet pipeline (10) and a control system; the outlet of the upstream pump (1) is connected to the delivery pipeline (3) for pressurizing the flammable liquid in the cabin and delivering it to the delivery pipeline (3); a flow meter (2) is provided on the delivery pipeline (3); the diameter of the delivery pipeline (3) is smaller than the diameter of the pump inlet pipeline (7), and the delivery pipeline (3) and the pump inlet pipeline (7) are connected through a reducer (4) with different diameters at both ends; the pump inlet pipeline (7) is connected to the inlet of the flammable liquid delivery pump (8); the outlet of the flammable liquid delivery pump (8) is connected to the pump outlet pipeline (10); a regulating valve (9) is also provided on the pump outlet pipeline (10); the flow meter (2), the flammable liquid delivery pump (8) and the regulating valve (9) are respectively electrically connected to the control system.

2. The flammable liquid long-distance pipeline pump protection system according to claim 1 is characterized in that: The pump inlet pipeline (7) includes a first conveying section, a second conveying section, a third conveying section, and a fourth conveying section that are connected in sequence; the first conveying section extends vertically upward, the second conveying section extends horizontally toward the direction of the flammable liquid conveying pump (8), the third conveying section extends vertically downward, and the fourth conveying section continues to extend horizontally toward the direction of the flammable liquid conveying pump (8); the reducer (4) is connected to the first conveying section; and the fourth conveying section is connected to the inlet of the flammable liquid conveying pump (8).

3. The flammable liquid long-distance pipeline transportation pump protection system according to claim 2 is characterized in that: The height of the conveying pipeline (3) is lower than the height of the second conveying section.

4. The flammable liquid long-distance pipeline transportation pump protection system according to claim 2 is characterized in that: The first conveying section is also connected to a first liquid level gauge (5) and a pressure gauge (6); the first liquid level gauge (5) and the pressure gauge (6) are respectively electrically connected to a control system.

5. The flammable liquid long-distance pipeline transportation pump protection system according to claim 4 is characterized in that: The combustible liquid delivery pump (8) is provided with a second liquid level gauge (11); the second liquid level gauge (11) is electrically connected to the control system.

6. The flammable liquid long-distance pipeline transportation pump protection system according to claim 1 is characterized in that: The diameter of the reducer (4) at the outlet is 1.5-2 times the diameter of the reducer (4) at the inlet.

7. The flammable liquid long-distance pipeline transportation pump protection system according to claim 5 is characterized in that: The flammable liquid delivery pump (8) is a centrifugal pump.

8. The flammable liquid long-distance pipeline transportation pump protection system according to claim 5 is characterized in that: The flammable liquid delivery pump (8) is a barrel bag pump.

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