Methanol fuel flow pressure adjusting method

Abstract

The invention relates to the technical field of fuel pressurization, in particular to a methanol fuel flow pressure adjusting method which comprises the following steps that a first bypass flow adjusting valve is arranged at a first methanol pump in parallel; opening an inlet switch valve between the low-pressure supply pipeline and the fuel storage tank; the opening degrees of a first methanol pump and a first bypass flow regulating valve are regulated, so that methanol fuel with a first set pressure value P1 is supplied to the methanol buffer cabinet through a low-pressure supply pipeline; the second methanol pump is communicated with the outlet end of the methanol buffer cabinet; a second bypass flow regulating valve is arranged at the second methanol pump in parallel; opening an outlet switch valve between the high-pressure supply pipeline and the user equipment; adjusting the opening degrees of a second methanol pump and a second bypass flow adjusting valve so as to supply methanol fuel with a second set pressure value P2 to the methanol buffer cabinet through the high-pressure supply pipeline, p2. The methanol supply flow and pressure can be effectively adjusted.

Description

Technical Field

[0001] This invention relates to the field of fuel pressurization technology, and in particular to a method for regulating the flow and pressure of methanol fuel. Background Technology

[0002] Methanol fuel is a new type of alternative fuel. Due to the toxicity, low flash point, and flammability and explosiveness of methanol, the methanol supply system differs significantly from that of conventional fuel oil. Methanol fuel is pressurized by pumps in the supply system and then delivered to methanol fuel user equipment.

[0003] Traditional methanol supply systems use variable frequency pumps (VFPs) to regulate the supply flow. However, since VFPs have an adjustment range of 30Hz-60Hz, the supply system cannot adjust when the methanol fuel user's demand is less than 30Hz. Furthermore, existing solutions cannot achieve real-time adjustment of methanol supply flow and pressure according to the main engine load, lacking dynamic response capabilities and the ability to adjust the methanol supply flow during low-load operation.

[0004] Therefore, a method for regulating the flow and pressure of methanol fuel is needed to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a method for regulating the flow rate and pressure of methanol fuel, which can effectively regulate the methanol supply flow rate and pressure.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] The method for regulating the flow and pressure of methanol fuel includes the following steps:

[0008] A first bypass flow regulating valve is connected in parallel at the first methanol pump.

[0009] Open the inlet valve between the low-pressure supply line and the fuel storage tank;

[0010] Adjust the opening of the first methanol pump and the first bypass flow regulating valve to supply methanol fuel at a first set pressure value P1 to the methanol buffer tank through the low-pressure supply pipeline;

[0011] The second methanol pump is connected to the outlet end of the methanol buffer tank, and a second bypass flow regulating valve is connected in parallel at the second methanol pump.

[0012] Open the outlet valve between the high-pressure supply pipeline and the user equipment;

[0013] Adjusting the opening of the second methanol pump and the second bypass flow regulating valve, thereby supplying methanol fuel at a second set pressure value P2 to the methanol buffer tank through the high-pressure supply pipeline, wherein P1 <P2。

[0014] In some embodiments, the method for regulating the supply of methanol fuel at the first set pressure value P1 to the methanol buffer tank includes the following steps:

[0015] Compare the outlet pressure P01 of the methanol fuel supplied by the first methanol pump with the first set pressure value P1. If P01 = P1, the first methanol pump and the first bypass flow regulating valve remain in their current states until a set amount of methanol fuel is loaded into the methanol buffer tank.

[0016] In some embodiments, if the outlet pressure P01 of the methanol fuel supplied by the first methanol pump is less than the first set pressure value P1, gradually reduce the opening degree of the first bypass flow regulating valve until P01 = P1. If P01 < P1 after the first bypass flow regulating valve is fully closed, then adjust the frequency of the first methanol pump to increase the rotational speed of the first methanol pump until P01 = P1.

[0017] In some embodiments, if the outlet pressure P01 of the methanol fuel supplied by the first methanol pump is greater than the first set pressure value P1, adjust the frequency of the first methanol pump to gradually reduce the speed until P01 = P1. If P01 > P1 after the first methanol pump operates at the lowest frequency, then gradually increase the opening degree of the first bypass flow regulating valve until P01 = P1.

[0018] In some embodiments, the method for regulating the supply of methanol fuel at the second set pressure value P2 to the user equipment includes the following steps:

[0019] Compare the outlet pressure P02 of the methanol fuel supplied by the second methanol pump with the second set pressure value P2. If P02 = P2, the second methanol pump and the second bypass flow regulating valve operate in their current states.

[0020] In some embodiments, if the outlet pressure P02 of the methanol fuel supplied by the second methanol pump is less than the second set pressure value P2, gradually reduce the opening degree of the second bypass flow regulating valve until P02 = P2. If P02 < P2 after the second bypass flow regulating valve is fully closed, then adjust the frequency of the second methanol pump to increase the rotational speed of the second methanol pump until P02 = P2.

[0021] In some embodiments, if the outlet pressure P02 of the methanol fuel supplied by the second methanol pump is greater than the second set pressure value P2, adjust the frequency of the second methanol pump to gradually reduce the speed until P02 = P2. If P02 > P2 after the second methanol pump operates at the lowest frequency, then gradually increase the opening degree of the second bypass flow regulating valve until P02 = P2.

[0022] In some embodiments, a first pressure sensor is provided at the inlet of the methanol buffer tank to detect the outlet pressure P01 of the methanol fuel supplied by the first methanol pump, and a second pressure sensor is provided at the inlet of the user equipment to detect the outlet pressure P02 of the methanol fuel supplied by the second methanol pump.

[0023] In some embodiments, the methanol buffer tank is equipped with a low level detection device and a high level detection device to detect the level of methanol fuel in the methanol buffer tank.

[0024] In some embodiments, a filter is provided on the low-pressure supply line to filter the methanol fuel entering the first methanol pump.

[0025] The beneficial effects of this invention are:

[0026] This invention provides a method for regulating the flow and pressure of methanol fuel. A first bypass flow regulating valve is connected in parallel at a first methanol pump, and a second bypass flow regulating valve is connected in parallel at a second methanol pump. During methanol fuel supply, the inlet valve of the low-pressure supply pipeline is opened, and the opening degrees of the first methanol pump and the first bypass flow regulating valve are adjusted, thereby supplying methanol fuel at a first set pressure value P1 to the methanol buffer tank through the low-pressure supply pipeline. Then, the opening degrees of the second methanol pump and the second bypass flow regulating valve are adjusted, thereby supplying methanol fuel at a second set pressure value P2 to the methanol buffer tank through the high-pressure supply pipeline. Through this method, a two-stage methanol fuel pressure regulation supply is achieved, and the pressure and flow rate of the methanol fuel supply can be precisely regulated at each stage by adjusting the methanol pump and the bypass flow regulating valve. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.

[0028] Figure 1 This is a flowchart of a methanol fuel flow and pressure regulation method according to the present invention;

[0029] Figure 2 This is a pipeline layout diagram in a methanol fuel flow and pressure regulation method of the present invention.

[0030] In the picture:

[0031] 11. Low-pressure supply pipeline; 12. First methanol pump; 13. Methanol buffer tank; 131. Low liquid level detection device; 132. High liquid level detection device; 14. First pressure sensor; 15. Inlet switch valve; 16. Filter; 161. Differential pressure sensor; 17. First bypass flow regulating valve; 21. High-pressure supply pipeline; 22. Second methanol pump; 23. Outlet switch valve; 24. Second pressure sensor; 25. Second bypass flow regulating valve. Detailed Implementation

[0032] Before explaining any implementation of this application in detail, it should be understood that this application is not limited to its application to the structural details and component arrangements set forth in the following description or shown in the above drawings.

[0033] In this application, the terms "comprising," "including," "having," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0034] In this application, the terms "connection," "combination," "coupling," and "installation" can refer to direct connection, combination, coupling, or installation, or indirect connection, combination, coupling, or installation. For example, a direct connection refers to two parts or components being connected together without the need for an intermediary, while an indirect connection refers to two parts or components each being connected to at least one intermediary, with the connection achieved through the intermediary. Furthermore, "connection" and "coupling" are not limited to physical or mechanical connections or couplings, but can also include electrical connections or couplings.

[0035] In this application, those skilled in the art will understand that the function performed by a component can be performed by one component, multiple components, one part, or multiple parts. Similarly, the function performed by a part can also be performed by one part, one component, or a combination of multiple parts.

[0036] In this application, the directional terms "upper," "lower," "left," "right," "front," and "rear" are used to describe the orientation and positional relationships shown in the accompanying drawings and should not be construed as limiting the embodiments of this application. Furthermore, in the context, it should be understood that when an element is mentioned as being connected "upper" or "lower" to another element, it can be directly connected to the other element "upper" or "lower," or indirectly connected through an intermediate element. It should also be understood that directional terms such as upper side, lower side, left side, right side, front side, and rear side not only represent positive orientation but can also be understood as lateral orientation. For example, "below" can include directly below, lower left, lower right, lower front, and lower rear.

[0037] When using methanol fuel to power user equipment, in order to effectively regulate the methanol supply flow rate and pressure, such as... Figure 1-Figure 2 As shown, this invention provides a method for regulating the flow rate and pressure of methanol fuel. The method for regulating the flow rate and pressure of methanol fuel includes the following steps:

[0038] A first bypass flow regulating valve 17 is connected in parallel at the first methanol pump 12;

[0039] Open the inlet valve 15 between the low-pressure supply line 11 and the fuel storage tank;

[0040] Adjust the opening of the first methanol pump 12 and the first bypass flow regulating valve 17, thereby supplying methanol fuel with a first set pressure value P1 to the methanol buffer tank 13 through the low-pressure supply pipeline 11.

[0041] The second methanol pump 22 is connected to the outlet end of the methanol buffer tank 13, and a second bypass flow regulating valve 25 is connected in parallel at the second methanol pump 22.

[0042] Open the outlet switch valve 23 between the high-pressure supply pipeline 21 and the user equipment;

[0043] Adjusting the opening of the second methanol pump 22 and the second bypass flow regulating valve 25, thereby supplying methanol fuel at a second set pressure value P2 to the methanol buffer tank 13 through the high-pressure supply pipeline 21, wherein P1 <P2。

[0044] The above method enables a two-stage methanol fuel pressure regulation supply, and each stage can precisely regulate the pressure and flow rate of the methanol fuel supply by adjusting the methanol pump and the bypass flow regulating valve.

[0045] In some embodiments, the method for regulating the supply of methanol fuel at a first set pressure value P1 to the methanol buffer tank 13 includes the following steps:

[0046] Compare the outlet pressure P01 of the methanol fuel supplied by the first methanol pump 12 with the first set pressure value P1. If P01 = P1, the first methanol pump 12 and the first bypass flow regulating valve 17 remain in their current states until a set amount of methanol fuel is loaded into the methanol buffer tank 13. In this way, it is possible to accurately determine whether to adjust the opening degrees of the first methanol pump 12 and the first bypass flow regulating valve 17 based on the outlet pressure P01 of the methanol fuel supplied by the first methanol pump 12.

[0047] In some embodiments, if the outlet pressure P01 of the methanol fuel supplied by the first methanol pump 12 is less than the first set pressure value P1, gradually reduce the opening degree of the first bypass flow regulating valve 17 until P01 = P1. If P01 < P1 after the first bypass flow regulating valve 17 is fully closed, adjust the frequency of the first methanol pump 12 to increase the rotational speed of the first methanol pump 12 until P01 = P1. By reducing the opening degree of the first bypass flow regulating valve 17, the flow rate of the methanol fuel flowing back to the inlet of the first methanol pump 12 can be reduced, thereby ensuring the flow rate of the methanol fuel supplied by the first methanol pump 12. When the first bypass flow regulating valve 17 is fully closed and still does not meet the requirements, the frequency of the first methanol pump 12 is increased by the frequency converter, thereby increasing the rotational speed of the first methanol pump 12, and thus increasing the flow rate and pressure until the requirements are met. In this way, by coordinating the first bypass flow regulating valve 17 and the first methanol pump 12, the supply pressure and flow rate of the methanol fuel can be effectively increased.

[0048] In some embodiments, if the outlet pressure P01 of the methanol fuel supplied by the first methanol pump 12 is greater than the first set pressure value P1, adjust the frequency of the first methanol pump 12 to gradually reduce the speed until P01 = P1. If P01 > P1 after the first methanol pump 12 operates at the lowest frequency, gradually increase the opening degree of the first bypass flow regulating valve 17 until P01 = P1. Adjust the frequency of the first methanol pump 12 by the frequency converter, thereby reducing the flow rate and pressure of the methanol supply. When the requirements cannot be met by adjusting the frequency of the first methanol pump 12, further adjust by adjusting the opening degree of the first bypass flow regulating valve, so as to accurately meet the pressure and flow rate of the methanol fuel supply.

[0049] In some embodiments, the adjustment method for supplying methanol fuel with a second set pressure value P2 to the user equipment includes the following steps: Compare the outlet pressure P02 of the methanol fuel supplied by the second methanol pump 22 with the second set pressure value P2. If P02 = P2, the second methanol pump 22 and the second bypass flow regulating valve 25 operate in their current states. In this way, it is possible to accurately determine whether to adjust the opening degrees of the second methanol pump 22 and the second bypass flow regulating valve 25 based on the outlet pressure P02 of the methanol fuel supplied by the second methanol pump 22.

[0050] In some embodiments, if the outlet pressure P02 of the methanol fuel supplied by the second methanol pump 22 is less than the second set pressure value P2, the opening degree of the second bypass flow regulating valve 25 is gradually reduced until P02 = P2. If P02 < P2 after the second bypass flow regulating valve 25 is completely closed, the frequency of the second methanol pump 22 is adjusted to increase the rotational speed of the second methanol pump 22 until P02 = P2. By reducing the opening degree of the second bypass flow regulating valve 25, the flow rate of the methanol fuel flowing back to the inlet of the second methanol pump 22 can be reduced, thereby ensuring the flow rate of the methanol fuel supplied by the second methanol pump 22. When the second bypass flow regulating valve 25 is completely closed and still does not meet the requirements, the frequency of the second methanol pump 22 is increased by the frequency converter, thereby increasing the rotational speed of the second methanol pump 22, thereby increasing the flow rate and pressure until the requirements are met. By the above method, by cooperating the second bypass flow regulating valve 25 and the second methanol pump 22, the supply pressure and flow rate of the methanol fuel can be effectively increased.

[0051] In some embodiments, if the outlet pressure P02 of the methanol fuel supplied by the second methanol pump 22 is greater than the second set pressure value P2, the frequency of the second methanol pump 22 is adjusted to gradually reduce the speed until P02 = P2. If P02 > P2 after the second methanol pump 22 operates at the lowest frequency, the opening degree of the second bypass flow regulating valve 25 is gradually increased until P02 = P2. The frequency of the second methanol pump 22 is adjusted by the frequency converter, thereby reducing the flow rate and pressure of the methanol supply. When the requirements cannot be met by adjusting the frequency of the second methanol pump 22, further adjustment is made by adjusting the opening degree of the second bypass flow regulating valve, so that the pressure and flow rate of the methanol fuel supply can be accurately met.

[0052] In some embodiments, a first pressure sensor 14 is provided at the inlet of the methanol buffer tank 13 to detect the outlet pressure P01 of the methanol fuel supplied by the first methanol pump 12, and a second pressure sensor 24 is provided at the inlet of the user equipment to detect the outlet pressure P02 of the methanol fuel supplied by the second methanol pump 22. By providing the first pressure sensor 14, the pressure of the methanol fuel subjected to primary pressurization can be effectively monitored in real time, thereby facilitating subsequent control of the opening degrees of the first methanol pump 12 and the first bypass flow regulating valve 17. By providing the second pressure sensor 24, the pressure of the methanol fuel subjected to secondary pressurization can be effectively monitored in real time, thereby facilitating subsequent control of the opening degrees of the second methanol pump 22 and the second bypass flow regulating valve 25.

[0053] In some embodiments, a low-level detection device 131 and a high-level detection device 132 are provided on the methanol buffer tank 13 to detect the methanol fuel level in the methanol buffer tank 13. By providing the low-level detection device 131, the amount of methanol fuel in the methanol buffer tank 13 can be detected in real time. Methanol fuel flows from the fuel storage tank into the methanol buffer tank 13 under its own weight. When there is methanol fuel in the methanol buffer tank 13, it is considered that the low-pressure supply pipeline 11 is full of methanol fuel. At this time, the first methanol pump 12 is started, which can prevent residual air in the low-pressure supply pipeline 11 from causing the methanol pump to run dry and cavitation, thereby ensuring the normal operation of the first methanol pump 12. By providing the high-level detection device 132, it is possible to detect in real time whether the amount of methanol fuel in the methanol buffer tank 13 has reached the set level. Since the height of the methanol buffer tank 13 is higher than that of the high-pressure supply pipeline 21, methanol fuel will flow into and fill the high-pressure supply pipeline 21 under the action of gravity. When the methanol fuel in the methanol buffer tank 13 reaches the set high level, it is determined that the high-pressure supply pipeline 21 is full of methanol fuel, and the second methanol pump 22 is started. This can prevent residual air in the high-pressure supply pipeline 21 from causing the methanol pump to run dry and cavitation, thereby ensuring the normal operation of the second methanol pump 22.

[0054] In some embodiments, a filter 16 is installed on the low-pressure supply line 11 to filter the methanol fuel entering the first methanol pump 12. The filter 16 can filter out impurities in the methanol fuel, thereby ensuring the cleanliness of the methanol fuel entering the methanol buffer tank 13, and also protecting the first methanol pump 12.

[0055] In some embodiments, a differential pressure sensor 161 is installed on the filter 16. By installing the differential pressure sensor 161, the inlet and outlet pressures of the filter 16 can be detected in real time, and the filter 16 can be analyzed to determine if it is clogged. When the difference between the inlet and outlet pressures is large, it indicates that the filter 16 is severely clogged and can no longer effectively filter, thus prompting personnel to replace the filter 16. Specifically, an alarm can be installed on the differential pressure sensor 161, which can provide an alarm via voice or light to serve as a reminder.

[0056] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for regulating the flow rate and pressure of methanol fuel, characterized in that, It includes the following steps: A first bypass flow regulating valve (17) is arranged in parallel at the first methanol pump (12); Open the inlet switch valve (15) between the low-pressure supply pipeline (11) and the fuel storage tank; Adjust the opening degrees of the first methanol pump (12) and the first bypass flow regulating valve (17), so as to supply methanol fuel with a first set pressure value P1 to the methanol buffer tank (13) through the low-pressure supply pipeline (11); The second methanol pump (22) is communicated with the outlet end of the methanol buffer tank (13), and a second bypass flow regulating valve (25) is arranged in parallel at the second methanol pump (22); Open the outlet switch valve (23) between the high-pressure supply pipeline (21) and the user equipment; Adjust the opening degrees of the second methanol pump (22) and the second bypass flow regulating valve (25), so as to supply methanol fuel with a second set pressure value P2 to the methanol buffer tank (13) through the high-pressure supply pipeline (21), where P1 < P2.

2. The methanol fuel flow rate and pressure regulation method according to claim 1, characterized in that, The adjusting method for supplying methanol fuel with the first set pressure value P1 to the methanol buffer tank (13) includes the following steps: Compare the outlet pressure P01 of the methanol fuel supplied by the first methanol pump (12) with the first set pressure value P1. If P01 = P1, the first methanol pump (12) and the first bypass flow regulating valve (17) are in the current state until a set amount of methanol fuel is loaded into the methanol buffer tank (13).

3. The methanol fuel flow rate and pressure regulation method according to claim 2, characterized in that, If the outlet pressure P01 of the methanol fuel supplied by the first methanol pump (12) is less than the first set pressure value P1, gradually reduce the opening degree of the first bypass flow regulating valve (17) until P01 = P1. If P01 < P1 after the first bypass flow regulating valve (17) is completely closed, adjust the frequency of the first methanol pump (12) to increase the rotational speed of the first methanol pump (12) until P01 = P1.

4. The methanol fuel flow rate and pressure regulation method according to claim 2, characterized in that, If the outlet pressure P01 of the methanol fuel supplied by the first methanol pump (12) is greater than the first set pressure value P1, adjust the frequency of the first methanol pump (12) to gradually reduce the speed until P01 = P1. If P01 > P1 after the first methanol pump (12) operates at the lowest frequency, gradually increase the opening degree of the first bypass flow regulating valve (17) until P01 = P1.

5. The methanol fuel flow rate and pressure regulation method according to claim 1, characterized in that, The adjusting method for supplying methanol fuel with the second set pressure value P2 to the user equipment includes the following steps: Compare the outlet pressure P02 of the methanol fuel supplied by the second methanol pump (22) with the second set pressure value P2. If P02 = P2, the second methanol pump (22) and the second bypass flow regulating valve (25) operate in the current state.

6. The methanol fuel flow rate and pressure regulation method according to claim 5, characterized in that, If the outlet pressure P02 of the methanol fuel supplied by the second methanol pump (22) is less than the second set pressure value P2, gradually reduce the opening degree of the second bypass flow regulating valve (25) until P02 = P2. If P02 < P2 after the second bypass flow regulating valve (25) is completely closed, adjust the frequency of the second methanol pump (22) to increase the rotational speed of the second methanol pump (22) until P02 = P2.

7. The methanol fuel flow rate and pressure regulation method according to claim 5, characterized in that, If the outlet pressure P02 of the methanol fuel supplied by the second methanol pump (22) is greater than the second set pressure value P2, adjust the frequency of the second methanol pump (22) to gradually reduce the speed until P02 = P2. If P02 > P2 after the second methanol pump (22) operates at the lowest frequency, gradually increase the opening degree of the second bypass flow regulating valve (25) until P02 = P2.

8. The method for regulating methanol fuel flow rate and pressure according to claim 1, characterized in that, A first pressure sensor (14) is provided at the inlet of the methanol buffer tank (13) to detect the outlet pressure P01 of the methanol fuel supplied by the first methanol pump (12), and a second pressure sensor (24) is provided at the inlet of the user equipment to detect the outlet pressure P02 of the methanol fuel supplied by the second methanol pump (22).

9. The method for regulating methanol fuel flow rate and pressure according to claim 1, characterized in that, A low liquid level detection device (131) and a high liquid level detection device (132) are provided on the methanol buffer tank (13) to detect the liquid level of the methanol fuel in the methanol buffer tank (13).

10. The method for regulating methanol fuel flow rate and pressure according to claim 1, characterized in that, A filter (16) is provided on the low-pressure supply pipeline (11) for filtering the methanol fuel entering the first methanol pump (12).

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