A marine fuel oil supply and return device and control method

Abstract

This invention discloses a marine fuel supply and return device and control method, belonging to the field of marine technology. The system includes: a steel fuel storage tank, whose inlet is connected to the fuel day tank via a supply pipeline, and whose return outlet is directly connected to the diesel engine return pipeline; a fuel supply power and metering unit, located on the supply pipeline, including a filter, a fuel pump, and an ultrasonic flow meter connected in sequence; a tank condition monitoring unit, located on the steel fuel storage tank, including at least a level gauge and a density meter or thermometer; a data acquisition and control unit, connected to the fuel pump, ultrasonic flow meter, and tank condition monitoring unit, used to control the start and stop of the fuel pump according to the liquid level, and to collect data on the fuel supply volume, the volume and density of the remaining fuel in the tank, and to calculate fuel consumption; and a data transmission unit for remotely transmitting fuel consumption data to a shore-based platform. This invention replaces the traditional float tank and return oil cooler with an integrated steel oil storage tank, simplifying the system structure and ensuring original factory maintenance of the diesel engine; at the same time, it uses a single ultrasonic flow meter combined with a material balance algorithm to achieve accurate fuel consumption measurement and supports remote data transmission, making it suitable for ship energy efficiency management and carbon intensity index calculation.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of ship technology, in particular to a comprehensive marine fuel supply and return device, which has the functions of a float tank and oil consumption measurement, and the core includes an oil consumption measurement device (including a measurement method), a data acquisition device, and a data transmission device. BACKGROUND

[0002] In a ship power device, it is crucial to stabilize the oil supply to the diesel engine. Some brands (such as widely used Cummins, etc.) of diesel engines use low-pressure oil supply. For ships with fuel daily tank at a higher position, in order to overcome the resistance of oil return, the traditional method is to add a float tank. The high-temperature oil return of the diesel engine (about 40% to 60% of the oil supply) is directly returned to the float tank. In order to ensure that the fuel viscosity meets the requirements of the diesel engine, an additional fuel return cooler needs to be installed to cool it, so that the mixed fuel viscosity in the float tank meets the manufacturer's standard, ensuring the stability of the diesel engine's fuel pump and fuel injector. At the same time, the fuel return cooler is usually water-cooled, and the common methods are: (1) diverting water from the sea water pump; (2) canceling the sea water pump and using the existing fresh water cooling pump to provide cooling water.

[0003] This scheme has the following defects: first, the addition of the float tank and the cooler and its piping system increases the width of the diesel generator set, occupying the space of the engine room passage; second, the added cooler usually needs to modify the original design of the diesel engine cooling device (such as diverting from the sea water pump or using fresh water cooling), which not only increases the complexity of the device, but also may cause the global warranty of the original factory to be invalid, increasing the risk and cost of ship operation. At the same time, the second method cannot guarantee the pressure value of the cooling water into the machine, according to the feedback from previous projects, the oil inlet pressure often exceeds the limit value of the diesel engine, causing internal cooler leakage and resulting in failure to stop.

[0004] On the other hand, accurate monitoring of ship fuel consumption is the basis for energy efficiency management (SEEMP) and carbon intensity index (CII) accounting. The traditional oil consumption measurement method usually sets a volumetric flowmeter on each of the diesel engine inlet and return pipes. This scheme has obvious shortcomings: first, two flowmeters increase the resistance of the device, especially in the float tank gravity oil supply device, which easily causes the diesel engine fuel pump to have difficulty in pumping oil; second, the volumetric flowmeter is a direct contact type instrument, which requires high oil cleanliness, and is prone to blockage when used for marine fuel, requiring frequent maintenance; third, this scheme usually only has local display or only connects the signal to the ship-mounted device, which cannot meet the needs of remote management on the shore.

[0005] Therefore, how to simplify the structure of the fuel supply device, ensure the efficient and stable operation of the diesel engine, and at the same time realize high-precision, low-maintenance, and remote transmission of oil consumption monitoring is a technical problem that needs to be solved in the field. SUMMARY

[0006] In view of the problems existing in the prior art, the present application aims to provide a marine fuel oil supply and return device and a control method, which are compact in structure, integrated in function, accurate in measurement and support remote data transmission.

[0007] To achieve the above-mentioned purpose, the technical scheme adopted by the present application is: A marine fuel oil supply and return device, comprising: A steel oil storage tank, whose oil inlet is connected with a fuel daily tank on a ship through a fuel supply pipeline, and whose oil return is directly connected with a diesel engine oil return pipeline, for receiving and mixing fuel from the fuel daily tank and hot return oil from the diesel engine; A fuel supply power and metering unit, arranged on the fuel supply pipeline, comprising a filter, an oil pump and a flow meter connected in sequence, the oil pump being used for pumping fuel in the fuel daily tank into the steel oil storage tank, and the flow meter being used for measuring the amount of fuel pumped into the steel oil storage tank; An in-tank state monitoring unit, arranged on the steel oil storage tank, comprising at least a liquid level meter for monitoring the volume of oil in the tank and a density meter for monitoring the density of oil or a temperature meter for converting the density; and A data acquisition and control unit, connected with the oil pump, the flow meter and the in-tank state monitoring unit, configured to: control the start and stop of the oil pump according to the monitoring signal of the liquid level meter, so as to maintain the liquid level in the steel oil storage tank within a preset range; acquire the fuel supply amount data measured by the flow meter and the volume and density data of the remaining oil in the tank monitored by the in-tank state monitoring unit in real time; and calculate the fuel consumption in a period of time based on the fuel supply amount data, the volume and density data of the remaining oil in the tank.

[0008] In the device described in the present application, the data acquisition and control unit calculates the fuel consumption in a period of time based on the following formula: M_consumption =Q_Δt - (ρ_end * V_end - ρ_start * V_start); M is the fuel consumption, Δt is the period of time, Q is the cumulative fuel supply amount measured by the flow meter in a unit of time, ρ is the density of the remaining oil in the tank measured by the density meter or the density converted from the temperature measured by the temperature meter, and V is the volume of the remaining oil in the tank measured by the liquid level meter.

[0009] In the device described in the present application, the device further comprises a data sending unit connected with the data acquisition and control unit, the data sending unit comprising a Beidou sending terminal or a 4G communication module, for regularly transmitting the fuel consumption data to a rear platform, such as a shore-based management platform or a ship energy efficiency management device.

[0010] In the device described in this invention, an explosion-proof solenoid valve is also provided on the oil supply pipeline after the flow meter. The explosion-proof solenoid valve is connected to the data acquisition and control unit and is used to discharge air in the pipeline when the device is started.

[0011] In the device described in this invention, the device further includes an emergency oil supply branch connected in parallel with the oil supply pipeline. One end of the emergency oil supply branch is connected to a filter in the oil supply pipeline, and the other end is connected to the daily oil tank on the ship. An emergency valve is provided on the emergency oil supply branch.

[0012] In the device described in this invention, the common base of the device is installed at a height lower than the lowest liquid level of the ship's fuel day tank. When the oil pump fails, the emergency valve opens, and the fuel in the fuel day tank is supplied to the steel oil storage tank by gravity through the emergency fuel supply branch.

[0013] In the device described in this invention, the top of the steel oil storage tank is provided with a venting pipe, and a pressure gauge and a venting valve are sequentially installed on the venting pipe, which extends to an open-air safe area.

[0014] In the device described in this invention, the data acquisition and control unit includes a main control box, which contains a PLC module, a hub, and a wireless module. The PLC module is configured to perform the control and calculation functions.

[0015] In the device described in this invention, the flow meter is installed on an upward-flowing measuring pipe section, which is a stainless steel pipe.

[0016] To achieve the above objectives, the present invention also provides a method for controlling marine fuel supply and return using the above-mentioned device, comprising the following steps: S1. Through the data acquisition and control unit, based on the liquid level signal in the steel oil storage tank, the oil pump is automatically controlled to start and stop, and fuel from the fuel day use tank is added to the steel oil storage tank. At the same time, the hot return oil from the diesel engine is received, so that the two are mixed in the tank. S2. Real-time acquisition of the cumulative oil supply Q measured by the flow meter, and the remaining oil volume V and density ρ measured by the tank condition monitoring unit; S3. Calculate the fuel consumption within the cycle time based on the following formula: M_consumption =Q_Δt - (ρ_end * V_end - ρ_start * V_start); M represents fuel consumption, Δt represents cycle time, and Q represents the cumulative fuel supply measured by the flow meter per unit time. S4. Transmit the calculated fuel consumption M data to the back-end platform, such as a shore-based management platform or a ship energy efficiency management device, through the data transmission unit.

[0017] Compared with the prior art, the present invention has the following beneficial effects: (1) High integration and simplified device: The fuel supply and return device provided by this invention can be independently arranged in the engine compartment. The volume of the steel oil tank inside can be appropriately adjusted according to the rated power of the diesel engine, thereby replacing the traditional float tank and fuel return cooler and its related piping system. At the same time, the high-temperature return oil of the diesel engine returns directly to the large-volume steel oil tank, mixes with the low-temperature fuel in the tank, and the cooling requirements of the return oil can be met by the heat dissipation of the tank itself, completely eliminating the need for a separate cooler, simplifying the device design, saving engine compartment space, and eliminating the need to modify the original diesel engine cooling device, thus ensuring the continuity of the original manufacturer's global maintenance. Based on this, the solution of this invention can eliminate the need for a fuel return cooler, the corresponding cooling water piping system, and the vent pipe from each float tank to the fuel day use compartment. The entire device is relatively simple and independent, which reduces costs and ensures the channel spacing and the continuity of the brand's global maintenance.

[0018] (2) Accurate measurement, low resistance and low maintenance: This invention adopts a combination of "oil pump supply + single flow meter" to measure oil consumption, replacing the traditional "inlet and return dual-volume flow meter" scheme. The oil pump provides a stable driving force for the device, overcoming the problem of high gravity oil supply resistance. The flow meter is a non-contact measurement, with no or extremely low pressure loss, and does not clog. It is highly adaptable to marine fuel, greatly reducing maintenance workload and improving the reliability and accuracy of measurement.

[0019] (3) Functional expansion to support intelligent ship management: This invention integrates a data acquisition and control unit and a data transmission unit (such as a Beidou terminal), which can not only realize local automatic control and fuel consumption calculation, but also remotely transmit the processed key data (such as fuel consumption) to the shore-based management platform. This provides a reliable data source for the accurate calculation of ship energy efficiency management (SEEMP) and carbon intensity index (CII), meeting the needs of digital and intelligent shipping management.

[0020] (4) Safe and reliable with multiple safeguards: Steel oil storage tanks are safer than traditional plastic float tanks. At the same time, the device is designed with an emergency oil supply branch, which can use gravity to achieve uninterrupted oil supply in the event of oil pump failure, greatly improving the reliability and safety of the ship's power plant. Attached Figure Description

[0021] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0022] Figure 1 This is a front view of the marine fuel supply and return device of the present invention.

[0023] Figure 2 for Figure 1 The image shows a side view of the marine fuel supply and return system.

[0024] Figure 3 for Figure 1 The diagram shows a top view of the marine fuel supply and return system.

[0025] Figure 4 This is a schematic diagram illustrating the application of the marine fuel supply and return device in a scenario where multiple diesel engines are used in conjunction.

[0026] Figure 5 This is a block diagram illustrating the principle of the data acquisition and control unit and the data transmission unit in this invention.

[0027] Explanation of component labels in the diagram: 01-Steel oil storage tank, 02-Filter, 03-Oil pump, 04-Measuring tube, 05-Ultrasonic flow meter, 06-Explosion-proof solenoid valve, 07-Emergency oil supply pipeline, 08-Emergency valve, 09-Ventilator, 10-Ventilator valve, 11-Pressure gauge, 12-Explosion-proof level gauge, 13-Density meter, 14-Electrical control box (including PLC, etc.), 15-Common base, A-Steel oil storage tank inlet, B-Steel oil storage tank outlet, C-Steel oil storage tank return port, D-Steel oil storage tank drain outlet. Detailed Implementation

[0028] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific illustrations.

[0029] like Figure 1 , Figure 2 and Figure 3 As shown, this embodiment provides a marine fuel supply and return device. The device is integrated on a common base 15, forming an independent, modular unit that can be hoisted as a whole, facilitating installation and maintenance in the ship's engine room.

[0030] As further explanation, the common base 15 is welded from steel profiles, providing sufficient structural strength. The installation location of the entire device is preferably chosen within the engine room, ensuring that the bottom surface of the common base 15 is below the lowest liquid level of the ship's day fuel tank (not shown in the figure). This height design enables the device to perform emergency fuel supply functions.

[0031] The ship's fuel supply and return system mainly consists of a steel oil storage tank 01, a filter 02, an oil pump 03, a measuring tube 04, a flow meter 05, an explosion-proof solenoid valve 06, a data acquisition and control unit, and a data transmission unit.

[0032] The steel oil storage tank 01 is the core container of this unit. It is manufactured using steel that meets marine standards, possessing sufficient strength and corrosion resistance. The volume of oil storage tank 01 is not a fixed value, but rather customized based on the rated power of the diesel engine it serves to ensure sufficient fuel reserve and thermal mixing capacity. For example, the volume of the steel oil storage tank 01 can be selected based on 1.5 to 2 times the hourly fuel consumption of the diesel engine.

[0033] like Figure 1 and Figure 2 As shown, the steel oil storage tank 01 is equipped with multiple functional interfaces, mainly including oil inlet A, oil outlet B, oil return C, sewage outlet D, and exhaust outlet.

[0034] The oil inlet A is separate from the steel oil storage tank 01 and is located near the bottom of the tank body, for connecting to the ship's day fuel tank. This configuration of oil inlet A allows for coordination with emergency fuel supply lines.

[0035] The oil outlet B is located in the lower middle part of the tank, slightly higher than the oil inlet A, and is used to supply fuel to the diesel engine. This arrangement of the oil outlet B ensures that even if there are a small amount of impurities settled at the bottom of the tank, they will not be sucked into the diesel engine's fuel supply line.

[0036] The return oil port C is located in the upper middle part of the tank and connects to the diesel engine's return oil. The high-temperature return oil from the diesel engine enters through this port, allowing it to mix with the low-temperature fuel in the upper space of the tank, which facilitates heat dissipation and oil-gas separation.

[0037] The drain outlet D is located at the very bottom of the tank and is used to periodically discharge the water and impurities that accumulate at the bottom of the tank.

[0038] The vent is located near the top of the tank and is used to connect to the venting pipe.

[0039] In addition, a pressure gauge 11 is installed on the top of the steel oil storage tank 01 to monitor the gas pressure inside the tank.

[0040] Based on the aforementioned steel oil storage tank 01, this embodiment introduces an oil supply pipeline to transport fuel from the day use compartment to the steel oil storage tank 01.

[0041] Combination Figure 1 and Figure 2 As shown, the oil supply pipeline is mainly composed of a filter 02, an oil pump 03, a measuring tube 04, a flow meter 05, and an explosion-proof solenoid valve 06.

[0042] The oil supply pipeline is drawn from the main oil supply pipe of the ship's fuel day tank and connected to the main oil inlet interface of this device, namely oil inlet A.

[0043] The oil inlet A is sequentially connected to filter 02, oil pump 03, measuring pipe 04, flow meter 05 and explosion-proof solenoid valve 06, thus forming the corresponding oil supply pipeline.

[0044] The filter 02 is located after the fuel inlet A, and its inlet is connected to the fuel inlet A. The filter 02 is used to remove mechanical impurities from the fuel and protect the downstream fuel pump 03 and flow meter 05.

[0045] Oil pump 03 is placed after filter 02, and the outlet of filter 02 is connected to the inlet of oil pump 03 via a pipeline. By introducing oil pump 03 into the pipeline, a stable oil supply can be achieved, allowing the flow meter to accurately measure oil consumption. Preferably, oil pump 03 is an electric gear pump or screw pump, providing stable delivery power to the device, thereby ensuring the stability of the oil supply.

[0046] Measuring tube 04 is placed after oil pump 03, with the outlet of oil pump 03 connected to the inlet of measuring tube 04. Measuring tube 04 is vertically arranged to create a test environment for measurement with flow meter 05. Preferably, measuring tube 04 is made of stainless steel pipe with a straight pipe section structure, forming a U-bend at one end of the straight pipe section. The diameter of measuring tube 04 is the same as that of the pipeline, and sufficient straight pipe length is provided before and after to meet the installation requirements of the ultrasonic flow meter and ensure that the ultrasonic signal remains uniformly distributed even after long-term use. With this structure, measuring tube 04 is vertically arranged, with one end of the straight pipe section serving as the inlet connected to the outlet of oil pump 03, and the other end of the U-bend serving as the outlet connected to the top of the oil storage tank.

[0047] The flow meter 05 is integrally mounted on the measuring tube 04 and is used to measure the flow rate of fuel passing through the measuring tube 04. Preferably, the flow meter 05 is an ultrasonic flow meter, and it is mounted on the measuring tube 04 with its transducer probe coupled to the outer surface of the tube wall. The installation position is selected in an upward-flowing vertical or inclined section of the tube to ensure that the tube is filled with liquid and to avoid measurement inaccuracies due to air bubble accumulation. The ultrasonic flow meter 05 is a non-contact measurement device with no pressure loss.

[0048] The explosion-proof solenoid valve 06 is placed after the flow meter 05 and installed on the lower end of the U-bend section of the measuring tube 04, and is controlled by the data acquisition and control unit.

[0049] Furthermore, the explosion-proof solenoid valve 06, with its design in this way, allows air to be released from the pipe during initial use by loosening the solenoid valve sealing screw, thus eliminating the influence of air on the measurement results.

[0050] Based on the above scheme, this example further includes an emergency oil supply branch to further improve the reliability of the entire device.

[0051] Combination Figure 1 andFigure 2 As shown, this emergency oil supply branch mainly consists of emergency oil supply pipeline 07 and emergency valve 08.

[0052] Among them, the emergency fuel supply line 07 is a bypass line, with one end connected to the line between the fuel inlet A and the filter 02, and the other end connected to the ship's daily fuel tank.

[0053] Emergency valve 08 is installed on emergency oil supply line 07 and is used to control the on / off state of emergency oil supply line 07.

[0054] The resulting emergency fuel supply branch is connected in parallel with the aforementioned fuel supply pipeline. Since the common base 15 of the fuel supply and return device should be lower than the lowest liquid level of the ship's day fuel tank, when the fuel pump 03 fails, the emergency valve 08 can be opened, and the fuel in the ship's day fuel tank can be gravity-fed to the steel fuel storage tank 01 through the emergency fuel supply pipeline 07 and the emergency valve 08, ensuring that the unit can quickly restore power supply.

[0055] Based on the above scheme, this example further includes an in-tank status monitoring unit to sense the oil parameters in the storage tank in real time.

[0056] See further Figure 1 and Figure 2 The tank condition monitoring unit set in this example is mainly composed of an explosion-proof level gauge 12 and a density gauge 13.

[0057] The explosion-proof level gauge 12 is installed on top of the steel oil storage tank 01. Its probe is vertically inserted into the tank and connected to the data acquisition and control unit, providing residual liquid level data for the steel oil storage tank 01. As an example, this embodiment uses a magnetostrictive level gauge or a radar level gauge, which can output continuous liquid level signals and transmit them to the data acquisition and control unit. The data acquisition and control unit can, on the one hand, automatically start and stop the oil pump based on the liquid level signal, controlling the pump to start at low pressure and stop at high pressure to achieve automatic oil replenishment; on the other hand, it can calculate the volume V of the fuel oil in the tank based on the liquid level signal.

[0058] A densitometer 13 is installed on the side wall or bottom of the steel oil storage tank 01. Its measuring probe is in contact with the fuel inside the tank to measure the fuel density ρ in real time. The densitometer 13 is connected to the data acquisition and control unit and can feed back the measured data to the data acquisition and control unit in real time. As an alternative, a thermometer can also be installed inside the tank to indirectly obtain the density value through a pre-established temperature-density conversion relationship.

[0059] Based on the above scheme, this example further includes a venting pipeline device to maintain pressure balance inside the tank.

[0060] See further Figure 1 andFigure 2 The ventilation pipeline device set in this example is mainly composed of ventilation pipe 09, ventilation valve 10 and pressure gauge 11.

[0061] Among them, the vent pipe 09 extends upward from the exhaust port at the top of the steel oil storage tank 01.

[0062] The vent valve 10 is installed on the vent pipe 09. It is a normally open valve and can be closed during maintenance.

[0063] Pressure gauge 11 is installed on vent pipe 09, located before vent valve 10, and is used to monitor the gas pressure inside the tank.

[0064] Additionally, a branch pipe can be led out from the outlet of valve 10 to a safe open area for ventilation. If several oil supply and return devices are combined for ventilation, the main ventilation pipe should be appropriately enlarged.

[0065] As further explanation, when the venting pipeline device is deployed, the venting pipe 09 on it continues to extend upward from the venting valve 10 to form a venting branch pipe, which passes through the ship's deck and finally leads to an open safety area (such as the main mast or a dedicated venting mast).

[0066] Furthermore, in scenarios where multiple diesel engines are used in conjunction, such as Figure 4 As shown, the vent pipes of multiple oil supply units can be connected in parallel to a single vent main pipe and then led to the open air. In this case, the diameter of the vent main pipe needs to be appropriately increased.

[0067] Based on the above scheme, this example further includes a drain pipe and a drain valve at the bottom of the steel oil storage tank 01 to discharge impurities from the steel oil storage tank 01.

[0068] The drain pipe is connected to the drain port at the bottom of the steel oil storage tank 01, and the drain valve is installed on the drain pipe to control the opening and closing of the drain pipe. Through the drain pipe and drain valve at the bottom, the drain valve can be opened periodically (such as daily or weekly) to use the pressure inside the tank or gravity to discharge the deposited water and impurities, ensuring that the fuel entering the diesel engine is always clean.

[0069] In this example, the data acquisition and control unit is mainly composed of an electrical control box 14, which is installed on the side of the steel oil storage tank 01.

[0070] Based on this, the electrical control box 14 integrates a PLC module, a hub / switch, and a wireless module.

[0071] The PLC module, or Programmable Logic Controller, is the core of the control system, containing a built-in CPU, power supply, and I / O interface modules. The PLC contains the control logic and calculation programs.

[0072] Hubs / switches connect and work with PLC modules to expand communication interfaces.

[0073] The wireless module connects and works with the PLC module to connect to a BeiDou transmitting terminal or other antennas. For example, the wireless module can be a 4G communication module.

[0074] The data acquisition and control unit thus formed can be electrically connected to the explosion-proof level gauge 12, density meter 13, ultrasonic flow meter 05, oil pump 03 and explosion-proof solenoid valve 06 via shielded cables during deployment.

[0075] Specifically, this data acquisition and control unit is connected to the explosion-proof level gauge 12 to receive 4-20mA or RS485 level signals.

[0076] This data acquisition and control unit is connected to the density meter 13 (or thermometer) to receive density / temperature signals.

[0077] This data acquisition and control unit is connected to the ultrasonic flow meter 05 to receive flow pulses or RS485 cumulative flow signals.

[0078] This data acquisition and control unit is connected to the motor control circuit of oil pump 03 to acquire oil pump operating status signals (optional).

[0079] This data acquisition and control unit is connected to the contactor coil of oil pump 03, and controls the start and stop of the oil pump through the PLC's DO (digital output) module.

[0080] This data acquisition and control unit is connected to the coil of the explosion-proof solenoid valve 06 to control the opening and closing of the solenoid valve.

[0081] See Figure 5 This data acquisition and control unit can be connected to the ship's display screen or computer via a communication cable for local data processing and display, and can also be connected to the data transmission unit for remote data transmission.

[0082] Furthermore, the data transmission unit in this example can be connected via communication lines to the data acquisition and control units in all marine fuel supply and return devices deployed on-site, or connected to a computer on board to acquire data generated by the data acquisition and control units in each marine fuel supply and return device. The data can be transmitted periodically to a back-end platform, such as a shore-based management platform or a ship energy efficiency management device, via a Beidou transmission terminal.

[0083] For example, the BeiDou transmitting terminal here can use a 4G or similar communication card to achieve data transmission.

[0084] The marine fuel supply and return device formed by this example solution is independently arranged in the engine room. The volume of the steel oil storage tank can be adjusted according to the rated power of the diesel engine. Therefore, it eliminates the need for fuel return coolers, corresponding cooling water pipe systems, and vent pipes from each float tank to the fuel day tank. The overall structure is relatively simple and independent, which reduces costs and ensures the channel spacing and the continuity of global maintenance by the brand.

[0085] Meanwhile, during operation, the ship's fuel supply and return system, based on the filters, oil pumps, measuring pipes, and flow meters installed in conjunction with the steel fuel tank, ensures that fuel from the day fuel tank passes through these components sequentially and is stored in the steel fuel tank, which is then supplied to the diesel engine's fuel pump. The diesel engine's return fuel goes directly back into the steel fuel tank, no longer returning to the day fuel tank, thus solving the problem of difficult fuel return caused by the high level of the day fuel tank. In addition, the volume of the steel fuel tank can be increased or decreased according to the diesel engine's power.

[0086] The following details the operation and workflow of the marine fuel supply and return device formed by this example solution.

[0087] The complete working process of this device is described in detail below, based on the above structure: Phase 1: Automatic fuel replenishment control and fuel mixing; Initial state: The device is powered on, and the PLC is initialized. Explosion-proof solenoid valve 06 is in the closed state, oil pump 03 is in the stopped state, and emergency valve 08 is in the closed state.

[0088] Liquid level detection: The PLC continuously reads the liquid level value L of the explosion-proof liquid level gauge 12.

[0089] Low-level start-up: When the liquid level L drops to the preset low-level threshold L_low (e.g., 30% of the tank volume), the PLC determines that oil replenishment is needed. First, the PLC outputs a signal to open the explosion-proof solenoid valve 06. After a delay of 1-2 seconds, the PLC outputs a signal to start the oil pump 03. Fuel from the fuel tank is drawn in, flows through the inlet A, filter 02, oil pump 03, measuring pipe 04 (measured by the ultrasonic flow meter 05), and explosion-proof solenoid valve 06, and finally enters the steel storage tank 01.

[0090] High-level stop: As fuel is continuously injected, the fuel level L gradually rises. When the fuel level L rises to the preset high-level threshold L_high (e.g., 80% of the tank volume), the PLC outputs a signal to stop the fuel pump 03. After a delay of 1-2 seconds, the PLC closes the explosion-proof solenoid valve 06 to prevent fuel backflow in the pipe.

[0091] Anti-sway and fault-prevention protection: The PLC program is equipped with delay logic (which can be implemented based on relay delay function). The oil pump will only start when the liquid level is below L_low for more than 5 seconds, avoiding accidental start-up due to ship rolling. At the same time, the PLC also has an internal timer. If the oil pump runs continuously for more than a preset maximum value (such as 30 minutes), it will forcibly stop the oil pump and issue an alarm even if the high liquid level has not been reached, to prevent oil spillage caused by liquid level gauge failure.

[0092] Return oil mixing: During diesel engine operation, high-temperature return oil continuously returns from return port C to the steel oil storage tank 01; due to the large tank volume, the high-temperature return oil mixes with a large amount of low-temperature fuel in the tank, and the temperature is quickly neutralized; the temperature of the mixed fuel can meet the working requirements of the diesel engine fuel pump, and no additional cooler is required.

[0093] Phase Two: Fuel Consumption Measurement under Normal Operating Conditions; Data Acquisition: Throughout the entire operation period of the diesel engine, the PLC acquires and accumulates the following data at fixed intervals (e.g., 1 second): Cumulative oil supply Q: Read the cumulative flow value from the ultrasonic flow meter 05.

[0094] Remaining volume V: Read the current liquid level L from the explosion-proof liquid level gauge 12, and calculate the current fuel volume V in the tank according to the "liquid level-volume" conversion table stored in the PLC (obtained from the geometric dimensions of the oil tank).

[0095] Residual density ρ: Read the current fuel density value ρ from density meter 13.

[0096] Material balance calculation: At the end of the set calculation cycle Δt (e.g., hourly, daily), the PLC extracts the fuel mass in the tank at the beginning of the cycle M_start (=ρ_start * V_start) and the fuel mass in the tank at the end of the cycle M_end (=ρ_end * V_end), and extracts the cumulative fuel supply Q_Δt within the cycle. According to the law of conservation of mass, the fuel consumption M_consumption within this cycle is calculated using the following formula: M_consumption = Q_Δt - (M_end - M_start) = Q_Δt - (ρ_end * V_end -ρ_start * V_start).

[0097] For scenarios requiring real-time display of instantaneous fuel consumption, the PLC can use a differential algorithm or a sliding window averaging method to calculate the fuel consumption rate per minute or hour based on the above principles.

[0098] Data output and storage: The calculated fuel consumption M_consumption, along with the raw data such as Q, V, and ρ, is stored in the PLC's internal memory and refreshed in real time on the ship's local display screen.

[0099] Phase Three: Operation Mode under Emergency Conditions; Fault Occurrence: If oil pump 03 fails to start due to motor burnout, jamming, or other reasons, or if the control device malfunctions and fails to automatically replenish oil.

[0100] Manual intervention: After confirming the oil pump malfunction, the crew manually opens emergency valve 08.

[0101] Gravity fuel supply: Since the installation height of the common base 15 is lower than the minimum liquid level of the fuel tank, after the emergency valve 08 is opened, the fuel in the fuel tank will automatically flow through the filter 02 (although the oil pump 03 is stopped at this time, the fuel can still pass through its internal channel), the emergency fuel supply line 07, and the emergency valve 08 by gravity, directly into the steel oil storage tank 01, to maintain the minimum fuel supply to the diesel engine and ensure that the ship's power is not interrupted.

[0102] Recovery and Repair: Repair or replace oil pump 03 when the ship docks or conditions permit. After repair, close emergency valve 08 and the device will return to normal operation.

[0103] Phase Four: Remote Data Transmission; Data Packaging: At a set time each day (e.g., 00:00 AM), the PLC automatically packages key data such as cumulative fuel consumption, average fuel consumption rate, and oil pump running time calculated over the past 24 hours into a data frame according to a preset data format.

[0104] Remote transmission: The PLC sends data frames to the Beidou transmitting terminal (or 4G communication module) via the RS485 interface. The Beidou transmitting terminal then transmits the data to the shipping company's shore-based management server via satellite or ground base station.

[0105] Shore-based processing: After receiving data, the server automatically parses and stores it, and can use it for advanced applications such as ship energy efficiency management (SEEMP) analysis, carbon intensity index (CII) calculation, and voyage fuel consumption report generation.

[0106] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A marine fuel oil supply and return device, characterized in that, include: The steel oil storage tank has its inlet connected to the ship's fuel day tank via an oil supply pipeline, and its return port directly connected to the diesel engine's return pipeline. It is used to receive and mix fuel from the fuel day tank and hot return oil returned from the diesel engine. A fuel supply power and metering unit is installed on the fuel supply pipeline and includes a filter, a fuel pump and a flow meter connected in sequence. The fuel pump is used to pump fuel from the fuel day tank into the steel fuel storage tank, and the flow meter is used to measure the amount of fuel pumped into the steel fuel storage tank. The tank condition monitoring unit is installed on the steel oil storage tank and includes at least a level gauge for monitoring the volume of oil in the tank and a density meter for monitoring the density of oil or a thermometer for converting density. as well as The data acquisition and control unit, connected to the oil pump, the flow meter, and the tank condition monitoring unit, is configured as follows: Based on the monitoring signal from the level gauge, the oil pump is controlled to start and stop, so as to maintain the liquid level in the steel oil storage tank within a preset range. The flow meter measures the oil supply data in real time, and the tank condition monitoring unit monitors the volume and density of the remaining oil in the tank. Based on the fuel supply data, the volume and density data of the remaining fuel in the tank, the fuel consumption within the cycle time is calculated.

2. The marine fuel oil supply and return device according to claim 1, characterized in that, The data acquisition and control unit calculates fuel consumption within a cycle time based on the following formula: M_consumption =Q_Δt - (ρ_end * V_end - ρ_start * V_start); M is the fuel consumption, Δt is the cycle time, Q is the cumulative fuel supply measured by the flow meter per unit time, ρ is the density of the remaining oil in the tank measured by the density meter or the density converted from the temperature measured by the thermometer, and V is the volume of the remaining oil in the tank measured by the level gauge.

3. The marine fuel oil supply and return device according to claim 1, characterized in that, The device also includes a data transmission unit connected to the data acquisition and control unit, which is used to periodically transmit the fuel consumption data to the back-end platform.

4. The marine fuel oil supply and return device according to claim 1, characterized in that, An explosion-proof solenoid valve is also installed on the oil supply pipeline after the flow meter. The explosion-proof solenoid valve is connected to the data acquisition and control unit and is used to discharge air from the pipeline when the device is started.

5. The marine fuel oil supply and return device according to claim 1, characterized in that, The device also includes an emergency fuel supply branch connected in parallel with the fuel supply pipeline. One end of the emergency fuel supply branch is connected to a filter in the fuel supply pipeline, and the other end is connected to the ship's day fuel tank. An emergency valve is provided on the emergency fuel supply branch.

6. The marine fuel oil supply and return device according to claim 5, characterized in that, The common base of the device is installed at a height lower than the lowest liquid level of the ship's fuel tank. When the oil pump fails, the emergency valve opens, and the fuel in the fuel tank is supplied to the steel storage tank by gravity through the emergency fuel supply branch.

7. The marine fuel oil supply and return device according to claim 1, characterized in that, The top of the steel oil storage tank is equipped with a venting pipe, on which a pressure gauge and a venting valve are installed in sequence, and the venting pipe extends to an open-air safe area.

8. The marine fuel oil supply and return device according to claim 1, characterized in that, The data acquisition and control unit includes a main control box, which contains a PLC module, a hub, and a wireless module. The PLC module is configured to perform the control and calculation functions.

9. The marine fuel oil supply and return device according to claim 1, characterized in that, The flow meter is installed on an upward-flowing measuring pipe section, which is made of stainless steel.

10. A method for controlling marine fuel oil supply and return using the apparatus as described in any one of claims 1 to 9, characterized in that, Includes the following steps: S1. Through the data acquisition and control unit, based on the liquid level signal in the steel oil storage tank, the oil pump is automatically controlled to start and stop, and fuel from the fuel day use tank is added to the steel oil storage tank. At the same time, the hot return oil from the diesel engine is received, so that the two are mixed in the tank. S2. Real-time acquisition of the cumulative oil supply Q measured by the flow meter, and the remaining oil volume V and density ρ measured by the tank condition monitoring unit; S3. Calculate the fuel consumption within the cycle time based on the following formula: M_consumption =Q_Δt - (ρ_end * V_end - ρ_start * V_start); M represents fuel consumption, Δt represents cycle time, and Q represents the cumulative fuel supply measured by the flow meter per unit time. S4. Transmit the calculated fuel consumption M data to the back-end platform through the data transmission unit.

Images