Flow velocity control method of shipping liquid medium in loading and unloading process and loading and unloading system of shipping liquid medium

Abstract

The invention discloses a flow velocity control method of a shipping liquid medium in a ship loading and unloading process and a ship loading and unloading system of the shipping liquid medium, and the method comprises the following steps: dividing the ship loading and unloading process of the shipping liquid medium into a plurality of control stages; different flow velocity control schemes are adopted corresponding to different control stages in combination with pipeline transportation requirements and liquid medium characteristics, a flow velocity model of each control stage is constructed, the ship loading and unloading flow velocity of the shipping liquid medium is controlled based on the constructed flow velocity models, flow velocity control is scientific and reasonable, manual flow velocity adjustment is avoided, and efficiency can be improved. According to the method, the water hammer effect caused by emergency valve closing due to the fact that the instantaneous value is too large in the ship loading and unloading process can be avoided through the flow velocity model in the control stage.

Description

Technical Field

[0001] The invention belongs to the technical field of automatic control, and in particular relates to a flow rate control method of a shipping liquid medium during a loading and unloading process of a ship, and a loading and unloading system of the shipping liquid medium. Background Art

[0002] Due to the particularity of liquid media such as petrochemical raw materials, they need to be transported to the destination safely and efficiently, and sea and river transportation provide this possibility. Sea transportation has become the main mode of transportation for petrochemical raw materials with its advantages of large capacity, low cost and high efficiency. River transportation is more suitable for transportation in inland areas, especially in some areas without direct coastlines. By connecting inland waterways, the transportation of raw materials can be achieved. In terms of the handover of raw materials, there is usually a set of detailed operating procedures and specifications to ensure the safe handover of raw materials. This includes inspections of the quantity, quality, safety and other aspects of the goods, as well as verification of relevant documents and receipts.

[0003] The operation of loading and unloading ships is a complex process. The traditional method of loading and unloading ships requires a lot of manual participation, and loading ships is carried out through a large number of batch controllers and DCS control systems. It is not only inefficient, but also prone to errors in the operation steps, resulting in overloading problems or water hammer effects caused by emergency valve closure due to excessive instantaneous values ​​during loading and unloading. Summary of the invention

[0004] In order to solve the problems existing in the prior art, the present invention provides a method for controlling the flow rate of a shipping liquid medium during the loading and unloading process of a ship and a loading and unloading system for the shipping liquid medium.

[0005] The technical solution of the present invention is as follows:

[0006] A method for controlling the flow rate of a shipping liquid medium during loading and unloading of a ship, comprising:

[0007] Dividing the loading and unloading process of the shipping liquid medium into several control stages;

[0008] Build the flow rate model for each control stage separately;

[0009] The flow rate of loading and unloading ships of shipping liquid media is controlled based on the constructed flow rate model.

[0010] Furthermore, the specific steps of dividing the loading and unloading process of the shipping liquid medium into several control stages include:

[0011] Obtain several historical flow and velocity data of the target ship's liquid medium during loading and unloading;

[0012] The flow rate and flow velocity data of each historical loading and unloading process are divided into several control stages based on the flow velocity change rate, and the ratio between the total loading volume in different control stages and the set cumulative total loading volume under the flow velocity data of each historical loading and unloading process is obtained;

[0013] Based on the ratio between the total loading volume in different control stages and the set cumulative total loading volume under each historical loading and unloading process flow rate data, the loading ratio threshold for each control stage is set.

[0014] Furthermore, the control stage includes a small flow stage, a ramp-up stage, a medium full pipe stage, a liquidation stage and an end stage.

[0015] Furthermore, the flow velocity model in the low flow stage is:

[0016] f ts =f min

[0017]

[0018] The anti-overloading constraint of the flow rate model in the low flow stage is:

[0019]

[0020] In the formula, f ts is the average flow velocity in the small flow stage; f min is the minimum flow rate of the liquid medium in shipping; f max is the maximum flow rate of the liquid medium in shipping; f ts i is the instantaneous flow velocity in the small flow stage; k ts is the overloading prevention coefficient in the low flow stage; q is the real-time total loading volume; Q is the set cumulative total loading volume; r ts is the loading ratio threshold for the set low flow stage.

[0021] Furthermore, the flow rate model in the ramp-up phase is:

[0022]

[0023]

[0024] The anti-overloading constraint of the flow rate model in the ramp-up phase is:

[0025]

[0026] In the formula, f tA is the average flow velocity in the ramp-up phase; f nor is the normal flow rate of the liquid medium in shipping; t A is the actual time of the wave climbing stage; T APlan time for the climbing phase; is the instantaneous flow velocity in the ramp-up phase; k tA is the anti-overloading coefficient in the climbing stage; r tA It is the loading ratio threshold value of the set ramp-up phase.

[0027] Furthermore, the flow velocity model of the medium in the full pipe stage is:

[0028] f tB =f nor

[0029]

[0030] The anti-overloading constraint of the velocity model in the medium full pipe stage is:

[0031]

[0032] In the formula, f tB is the average flow rate of the medium in the full tube stage; k is the instantaneous flow rate of the medium in the full tube stage; tB is the overfill prevention coefficient when the medium is full in the pipe; r tB It is the loading ratio threshold value of the medium full pipe stage.

[0033] Furthermore, the flow rate model of the liquidation stage is:

[0034]

[0035]

[0036] The anti-overloading constraint of the flow rate model in the liquidation stage is:

[0037]

[0038] In the formula, f tC is the average flow rate in the liquidation phase; t C T is the actual time of the closing phase; C Plan time for the liquidation phase; is the instantaneous flow rate in the liquidation phase; k tC is the anti-overloading coefficient in the liquidation stage; r tC It is the loading ratio threshold for the set closing phase.

[0039] Furthermore, the flow rate model of the end stage is:

[0040] f tE =f min

[0041]

[0042] The anti-overloading constraint of the flow rate model in the end stage is:

[0043]

[0044] In the formula, f tE is the average flow velocity at the end stage; is the instantaneous flow velocity at the end stage; k tE is the anti-overloading coefficient at the end stage; r tE It is the loading ratio threshold for the set closing phase.

[0045] A ship loading and unloading system for a shipping liquid medium, comprising a loading and unloading arm connected to a ship body, a ship unloading pipeline connected to the loading and unloading arm, a flow meter arranged on the ship unloading pipeline and used to measure the flow rate and accumulated flow of the shipping liquid medium, a pressure sensor used to measure the pressure value of the shipping liquid medium, a temperature sensor and a regulating valve used to measure the temperature value of the shipping liquid medium, and a DCS control system communicatively connected to the flow meter, the pressure sensor, the temperature sensor and the regulating valve;

[0046] The DCS control system corrects the flow rate value according to the pressure value and the temperature value to obtain a corrected flow rate value;

[0047] The DCS control system uses the corrected flow rate value as the loading and unloading flow rate of the shipping liquid medium, adopts the above-mentioned flow rate control method of the shipping liquid medium during the loading and unloading process, controls the loading and unloading flow rate of the shipping liquid medium by adjusting the opening of the regulating valve, and performs cumulative overloading prevention warning control according to the cumulative flow.

[0048] Furthermore, the specific method for performing cumulative overloading prevention early warning control according to the cumulative flow rate includes:

[0049] The accumulated flow is compared with an accumulated flow threshold, and if the accumulated flow is greater than or equal to the accumulated flow threshold, the loading and unloading of the ship is stopped by adjusting the opening of the regulating valve.

[0050] An electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor is used to call and run the computer program stored in the memory to execute any of the methods described above.

[0051] A computer-readable storage medium stores a computer program, wherein the computer program implements the steps of any of the above methods when executed by a processor.

[0052] Compared with the prior art, the present invention has the following beneficial effects:

[0053] The present invention proposes a method for controlling the flow rate of a shipping liquid medium during the loading and unloading process of a ship. The method divides the loading and unloading process of the shipping liquid medium into several control stages, adopts different flow rate control schemes corresponding to different control stages in combination with pipeline transportation requirements and liquid medium characteristics, and constructs a flow rate model for each control stage. The loading and unloading flow rate of the shipping liquid medium is controlled based on the constructed flow rate model. The flow rate control is scientific and reasonable, avoids manual flow rate adjustment, and can improve efficiency.

[0054] The velocity control method of the present invention is provided with an anti-overloading constraint corresponding to the velocity model in the control stage. The technicians can adaptively adjust the anti-overloading coefficient in the anti-overloading constraint in different control stages according to the pipeline transportation requirements and the liquid medium characteristics, so that the velocity control model of each control stage is adapted to the pipeline transportation requirements and the liquid medium characteristics, thereby avoiding the water hammer effect caused by the emergency valve closing due to the excessive instantaneous value during the loading and unloading process.

[0055] The present invention proposes a ship loading and unloading system for shipping liquid media. The ship loading and unloading system has a simple structure and includes a loading and unloading arm, an unloading pipeline, a flow meter, a pressure sensor, a temperature sensor, a regulating valve and a DCS control system. It does not require the use of a large number of batch controllers and is particularly suitable for situations where trade transfer is performed based on ship measurement, and can reduce the investment in batch controllers or flow computers. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 Flow chart of the method for controlling the flow rate of a shipping liquid medium during loading and unloading of a ship in an embodiment;

[0057] Figure 2 This is a schematic diagram of the control stage division in the embodiment;

[0058] Figure 3 It is a flowchart of the loading and unloading process of a chemical product terminal in the embodiment. DETAILED DESCRIPTION

[0059] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent modifications of the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0060] Embodiment 1:

[0061] The present invention provides a method for controlling the flow rate of a shipping liquid medium during loading and unloading of a ship, such as Figure 1 Shown, including

[0062] S1. Divide the loading and unloading process of liquid medium into several control stages;

[0063] S2, construct the flow rate model for each control stage respectively;

[0064] S3. Control the loading and unloading flow rate of the shipping liquid medium based on the constructed flow rate model.

[0065] The flow rate control method of the present invention divides the loading and unloading process of the shipping liquid medium into several control stages, adopts different flow rate control schemes corresponding to different control stages in combination with pipeline transportation requirements and liquid medium characteristics, constructs a flow rate model for each control stage, and controls the loading and unloading flow rate of the shipping liquid medium based on the constructed flow rate model. The flow rate control is scientific and reasonable, avoids manual flow rate adjustment, and can improve efficiency.

[0066] Embodiment 2:

[0067] This embodiment is further designed on the basis of the first embodiment in that the specific steps of dividing the loading and unloading process of the shipping liquid medium into several control stages in this embodiment include:

[0068] Obtain several historical flow and velocity data of the target shipping liquid medium during loading and unloading; the target shipping liquid medium here refers to a liquid medium of a specific shipping specification and a specific type. Affected by the type of liquid medium and the shipping specification, the control stages of different types of liquid media and / or liquid media of different shipping specifications may be different, so the division of the control stages needs to be carried out separately.

[0069] The flow rate and flow velocity data of each historical loading and unloading process are divided into several control stages based on the flow velocity change rate, and the ratio between the total loading volume in different control stages and the set cumulative total loading volume under the flow velocity data of each historical loading and unloading process is obtained;

[0070] Based on the ratio between the total amount of loading in different control stages and the set cumulative total amount of loading under each historical loading and unloading process flow rate data, the ratio between the total amount of loading in each control stage and the set cumulative total amount of loading is set. The ratio can be the average of multiple ratios.

[0071] Embodiment three:

[0072] This embodiment is further designed on the basis of the first embodiment in that: Figure 2 As shown, the control stages in this example include a small flow stage, a ramp-up stage, a medium full pipe stage, a liquidation stage, and an end stage.

[0073] Embodiment 4:

[0074] This embodiment is further designed on the basis of the third embodiment in that: Figure 2 As shown in the figure, the velocity model of the small flow stage in this example is:

[0075] fts =f min

[0076]

[0077] The anti-overloading constraint of the velocity model in the low flow stage is:

[0078]

[0079] In the formula, f ts is the average flow velocity in the small flow stage; f min is the minimum flow rate of the liquid medium in shipping; f max The maximum flow rate of the liquid medium being transported in a ship; is the instantaneous flow velocity in the small flow stage; k ts is the overloading prevention coefficient in the low flow stage; q is the real-time total loading volume; Q is the set cumulative total loading volume; r ts is the loading ratio threshold for the set low flow stage.

[0080] Embodiment five:

[0081] This embodiment is further designed on the basis of the fourth embodiment in that: Figure 2 As shown in the figure, the flow velocity model in the ramp-up phase in this example is:

[0082]

[0083]

[0084] The anti-overloading constraint of the flow rate model in the ramp-up phase is:

[0085]

[0086] In the formula, f tA is the average flow velocity in the ramp-up phase; f nor is the normal flow rate of the liquid medium in shipping; t A is the actual time of the wave climbing stage; T A Plan time for the climbing phase; is the instantaneous flow velocity in the ramp-up phase; k tA is the anti-overloading coefficient in the climbing stage; r tA It is the loading ratio threshold value of the set ramp-up phase.

[0087] Embodiment six:

[0088] This embodiment is further designed on the basis of the fifth embodiment in that: Figure 2 As shown in the figure, the flow velocity model of the medium in the full tube stage in this example is:

[0089] f tB =fnor

[0090]

[0091] The anti-overloading constraint of the velocity model in the medium full pipe stage is:

[0092]

[0093] In the formula, f tB is the average flow rate of the medium in the full tube stage; k is the instantaneous flow rate of the medium in the full tube stage; tB is the overfill prevention coefficient when the medium is full in the pipe; r tB It is the loading ratio threshold value of the medium full pipe stage.

[0094] Embodiment seven:

[0095] This embodiment is further designed on the basis of the sixth embodiment in that: Figure 2 As shown in the figure, the flow rate model of the closing phase in this example is:

[0096]

[0097]

[0098] The anti-overloading constraint of the flow rate model in the liquidation phase is:

[0099]

[0100] In the formula, f tC is the average flow rate in the liquidation phase; t C T is the actual time of the closing phase; C Plan time for the liquidation phase; is the instantaneous flow rate in the liquidation phase; k tC is the anti-overloading coefficient in the liquidation stage; r tC It is the loading ratio threshold for the set closing phase.

[0101] Embodiment eight:

[0102] This embodiment is further designed on the basis of the seventh embodiment in that: Figure 2 As shown in the figure, the velocity model at the end of this example is:

[0103] f tE =f min

[0104]

[0105] The anti-overloading constraint of the flow rate model at the end stage is:

[0106]

[0107] In the formula, f tE is the average flow velocity at the end stage; is the instantaneous flow velocity at the end stage; k tE is the anti-overloading coefficient at the end stage; r tE It is the loading ratio threshold for the set closing phase.

[0108] Embodiment nine:

[0109] A loading and unloading ship system for a liquid medium transported by a ship of the present invention, such as Figure 3 As shown, it includes a loading and unloading arm connected to the hull, a ship unloading pipeline connected to the loading and unloading arm, a flow meter arranged on the ship unloading pipeline and used to measure the flow rate and cumulative flow of the shipping liquid medium, a pressure sensor used to measure the pressure value of the shipping liquid medium, a temperature sensor and a regulating valve used to measure the temperature value of the shipping liquid medium, and a DCS control system connected to the flow meter, the pressure sensor, the temperature sensor and the regulating valve;

[0110] The DCS control system corrects the flow rate value according to the pressure value and the temperature value to obtain the corrected flow rate value;

[0111] The DCS control system uses the corrected flow rate value as the loading and unloading flow rate of the shipping liquid medium, and adopts the flow rate control method of the shipping liquid medium during the loading and unloading process as recorded in any of the above embodiments, controls the loading and unloading flow rate of the shipping liquid medium by adjusting the opening of the regulating valve, and performs cumulative overloading prevention warning control based on the cumulative flow rate.

[0112] Embodiment ten:

[0113] This example is further designed on the basis of the ninth embodiment in that the specific method for performing cumulative overloading prevention early warning control according to the cumulative flow rate in this example includes:

[0114] The accumulated flow is compared with the accumulated flow threshold. If the accumulated flow is greater than or equal to the accumulated flow threshold, the loading and unloading of the ship is stopped by adjusting the opening of the regulating valve.

[0115] Embodiment eleven:

[0116] An electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor is used to call and run the computer program stored in the memory to execute any of the methods described above.

[0117] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of any of the above methods are implemented.

[0118] The above description is only a specific implementation of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a technician familiar with the technical field within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention.

Claims

1. A method for controlling the flow rate of a shipping liquid medium during loading and unloading of a ship, characterized in that: It includes dividing the loading and unloading process of the shipping liquid medium into several control stages; Build the flow rate model for each control stage separately; The flow rate of loading and unloading ships of shipping liquid media is controlled based on the constructed flow rate model.

2. The method for controlling the flow rate of a shipping liquid medium during loading and unloading of a ship according to claim 1, characterized in that: The specific steps of dividing the loading and unloading process of the shipping liquid medium into several control stages include: Obtain several historical flow and velocity data of the target ship's liquid medium during loading and unloading; The flow rate and flow velocity data of each historical loading and unloading process are divided into several control stages based on the flow velocity change rate, and the ratio between the total loading volume in different control stages and the set cumulative total loading volume under the flow velocity data of each historical loading and unloading process is obtained; Based on the ratio between the total loading volume in different control stages and the set cumulative total loading volume under each historical loading and unloading process flow rate data, the loading ratio threshold for each control stage is set.

3. The method for controlling the flow rate of a shipping liquid medium during loading and unloading of a ship according to claim 1, characterized in that: The control stages include a small flow stage, a ramp-up stage, a medium full pipe stage, a liquidation stage and an end stage.

4. The method for controlling the flow rate of a shipping liquid medium during loading and unloading of a ship according to claim 2, characterized in that: The flow velocity model in the small flow stage is: f ts =f min The anti-overloading constraint of the flow rate model in the low flow stage is: In the formula, f ts is the average flow velocity in the small flow stage; f min is the minimum flow rate of the liquid medium in shipping; f max The maximum flow rate of the liquid medium being transported in a ship; is the instantaneous flow velocity in the small flow stage; k ts is the overloading prevention coefficient in the low flow stage; q is the real-time total loading volume; Q is the set cumulative total loading volume; r ts is the loading ratio threshold for the set low flow stage.

5. The method for controlling the flow rate of a shipping liquid medium during loading and unloading of a ship according to claim 3, characterized in that: The flow rate model in the ramp-up phase is: The anti-overloading constraint of the flow rate model in the ramp-up phase is: In the formula, f tA is the average flow velocity in the ramp-up phase; f nor is the normal flow rate of the liquid medium in shipping; t A is the actual time of the wave climbing stage; T A Plan time for the climbing phase; is the instantaneous flow velocity in the ramp-up phase; k tA is the anti-overloading coefficient in the climbing stage; r tA It is the loading ratio threshold value of the set ramp-up phase.

6. The method for controlling the flow rate of a shipping liquid medium during loading and unloading of a ship according to claim 5, characterized in that: The flow velocity model of the medium in the full tube stage is: f tB =f nor The anti-overloading constraint of the velocity model in the medium full pipe stage is: In the formula, f tB is the average flow rate of the medium in the full tube stage; k is the instantaneous flow rate of the medium in the full tube stage; tB is the overfill prevention coefficient when the medium is full in the pipe; r tB It is the loading ratio threshold value of the medium full pipe stage.

7. The method for controlling the flow rate of a shipping liquid medium during loading and unloading of a ship according to claim 6, characterized in that: The flow rate model of the liquidation stage is: The anti-overloading constraint of the flow rate model in the liquidation stage is: In the formula, f tC is the average flow rate in the liquidation phase; t C The actual time of the closing phase; T C Plan time for the liquidation phase; is the instantaneous flow rate in the liquidation phase; k tC is the anti-overloading coefficient in the liquidation stage; r tC It is the loading ratio threshold for the set closing phase.

8. The method for controlling the flow rate of a shipping liquid medium during loading and unloading of a ship according to claim 7, characterized in that: The flow rate model of the end stage is: f tE =f min The anti-overloading constraint of the flow rate model in the end stage is: In the formula, f tE is the average flow velocity at the end stage; is the instantaneous flow velocity at the end stage; k tE is the anti-overloading coefficient at the end stage; r tE It is the loading ratio threshold for the set closing phase.

9. A ship loading and unloading system for shipping liquid medium, comprising a loading and unloading arm connected to a ship hull and a ship unloading pipeline connected to the loading and unloading arm, characterized in that: It also includes a flow meter disposed on the unloading pipeline and used to measure the flow rate and accumulated flow of the shipping liquid medium, a pressure sensor used to measure the pressure value of the shipping liquid medium, a temperature sensor and a regulating valve used to measure the temperature value of the shipping liquid medium, and a DCS control system connected to the flow meter, the pressure sensor, the temperature sensor and the regulating valve; The DCS control system corrects the flow rate value according to the pressure value and the temperature value to obtain a corrected flow rate value; The DCS control system uses the corrected flow rate value as the loading and unloading flow rate of the shipping liquid medium, adopts the flow rate control method of the shipping liquid medium in the loading and unloading process of the shipping liquid medium as described in any one of claims 1 to 8, controls the loading and unloading flow rate of the shipping liquid medium by adjusting the opening of the regulating valve, and performs cumulative overloading prevention warning control based on the cumulative flow rate.

10. The loading and unloading ship system for shipping liquid medium according to claim 9, characterized in that: The specific method of performing cumulative overloading prevention early warning control according to the cumulative flow rate includes: The accumulated flow is compared with an accumulated flow threshold, and if the accumulated flow is greater than or equal to the accumulated flow threshold, the loading and unloading of the ship is stopped by adjusting the opening of the regulating valve.

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