Grain and oil production process control method

Abstract

The invention provides a grain and oil production process control method, which comprises the following steps: acquiring the temperature, depth, specific volume and flow of oil in each storage tank in real time, releasing pressure if the specific volume exceeds the upper limit, and supplementing pressure and outputting oil at constant pressure if the specific volume is lower than the lower limit; if the oil depth is insufficient, the oil is supplemented to the normal depth, and automatic steady-state control over the oil product in the storage tank is achieved. Automatic and refined management of the oil state in the grain and oil production process can be achieved, the production efficiency and the product quality are improved, and the safety and stability of the production process are enhanced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of automatic control of grain and oil production, and more particularly to a grain and oil production process control method. BACKGROUND

[0002] In the process of grain and oil production, the storage and transportation of oil products are key links. The existing oil product storage tank control system can usually only simply monitor the liquid level of the oil, and lacks the ability to monitor and accurately control key parameters such as the specific volume and temperature of the oil in real time. This traditional control method is prone to cause the specific volume of the oil to exceed the safe range, affecting the flowability and transportation efficiency of the oil, and even possibly causing abnormal pressure of the storage tank, increasing the safety risk. At the same time, the oil replenishment and pressure relief operations of the storage tank often rely on manual judgment, lacking automated and intelligent control means, resulting in low operation efficiency and making it difficult to achieve accurate oil management.

[0003] Specifically, the existing technology has the following main defects: first, the specific volume parameter of the oil cannot be monitored in real time, which makes it impossible to adjust the pressure of the storage tank in a timely manner, and is prone to cause the specific volume of the oil to exceed the safe range; second, there is a lack of intelligent control of the pressure relief and pressure compensation process, which cannot dynamically adjust the valve state according to the oil temperature and other parameters; third, the control precision of the oil storage depth is insufficient, which cannot achieve automatic oil replenishment and oil discharge control; and finally, there is a lack of real-time monitoring means for the state of the oil, which cannot accurately judge the flow state of the oil. These problems seriously affect the stability and safety of grain and oil production, increasing the frequency of manual intervention and the risk of operation errors. SUMMARY

[0004] The present application provides a grain and oil production process control method, comprising:

[0005] Step S1, real-time collection of oil product outflow control parameters of each storage tank, the outflow control parameters including the oil temperature of the storage tank, the standard oil storage depth of the oil, the real-time oil storage depth of the storage tank, the specific volume of the oil of the storage tank, and the flow rate;

[0006] Step S2, judgment of whether the specific volume of the oil of each storage tank stored oil product conforms to a predetermined range:

[0007] When the specific volume of the oil is greater than a specific volume predetermined upper deviation value, a pressure relief valve of the corresponding storage tank is controlled to relieve pressure until the specific volume of the oil is less than or equal to the specific volume predetermined upper deviation value;

[0008] When the specific volume of the oil is less than a specific volume predetermined lower deviation value, a pressure compensation valve of the corresponding storage tank is controlled to compensate pressure until the oil is discharged at a constant oil pressure from the oil discharge end of the corresponding storage tank;

[0009] Step S3, judgment of whether the real-time oil storage depth of the storage tank of each storage tank stored oil product conforms to a predetermined depth:

[0010] When the real-time oil storage depth of the oil storage tank is less than the normal oil storage depth of the oil storage tank, the oil supplement valve of the corresponding oil storage tank is controlled to supplement oil until the real-time oil storage depth of the oil storage tank is greater than or equal to the normal oil storage depth of the oil storage tank.

[0011] Further, the controlling the pressure relief valve of the corresponding oil storage tank to perform pressure relief comprises:

[0012] Step S21, receiving a pressure relief instruction for pressure relief;

[0013] Step S22, judging a pressure relief state of the pressure relief valve, the pressure relief state comprising a pressure relief state and a non-pressure relief state;

[0014] When the pressure relief valve is in the non-pressure relief state, according to the pressure relief instruction, it is judged whether the pressure relief oil temperature is greater than or equal to a pressure relief temperature threshold value, if yes, the pressure relief valve is controlled to be opened to perform pressure relief;

[0015] When the pressure relief valve is in the pressure relief state, according to the pressure relief instruction, it is judged whether the pressure relief oil temperature is less than the pressure relief temperature threshold value, if yes, the pressure relief valve is controlled to be opened to perform pressure relief;

[0016] Step S23, repeating step S22, and when the pressure relief valve is in the pressure relief state, the pressure relief valve is controlled to be closed to stop pressure relief when the pressure relief oil temperature is greater than or equal to the pressure relief temperature threshold value.

[0017] Collecting the pressure relief oil temperatures of the oil liquid at different time periods at different times, and judging the stability of the real-time pressure relief state based on the dispersion degree according to the liquid output rate of the pressure relief valve.

[0018] Further, the judging the stability of the real-time pressure relief state based on the dispersion degree comprises: step S231, extracting the pressure relief oil temperatures at different times;

[0019] Step S232, judging whether the difference between the maximum value and the minimum value of the pressure relief oil temperature meets: if the difference between the maximum value and the minimum value of the pressure relief oil temperature is less than or equal to a preset dispersion degree predetermined threshold value, step S234 is entered;

[0020] Step S233, if the difference between the maximum value and the minimum value of the pressure relief oil temperature is greater than the preset dispersion degree predetermined threshold value, it is judged whether the time difference between the time corresponding to the minimum value of the pressure relief oil temperature and the time corresponding to the maximum value of the pressure relief oil temperature meets: if the time difference is less than or equal to a preset time difference threshold value, the pressure relief valve is controlled to stop pressure relief; if the time difference is greater than the preset time difference threshold value, the pressure relief valve is controlled to continue pressure relief.

[0021] Step S234, when the pressure relief valve keeps pressure relief time greater than or equal to the time difference threshold, judging whether the pressure relief oil temperature meets: if the pressure relief oil temperature is greater than or equal to the pressure relief temperature threshold, controlling the pressure relief valve to continue pressure relief; if the pressure relief oil temperature is less than the pressure relief

[0022] temperature threshold, controlling the pressure relief valve to stop pressure relief.

[0023] Further, the control of the pressure relief valve of the corresponding storage tank to supplement pressure comprises:

[0024] Step S41, receiving a supplement pressure instruction for supplement pressure;

[0025] Step S42, judging the supplement pressure state of the pressure relief valve, the supplement pressure state comprising a supplement pressure state and a non-supplement pressure state;

[0026] When the pressure relief valve is in the non-supplement pressure state, according to the supplement pressure instruction, judging whether the supplement pressure oil temperature is greater than the supplement pressure temperature threshold, if yes, controlling the pressure relief valve to open to supplement pressure;

[0027] When the pressure relief valve is in the supplement pressure state, according to the supplement pressure instruction, judging whether the supplement pressure oil temperature is less than the supplement pressure temperature threshold, if yes, controlling the pressure relief valve to open to supplement pressure;

[0029] Step S43, repeating step S42, and when the pressure relief valve is in the supplement pressure state, collecting supplement pressure oil temperatures of oil at different time periods at different times, and judging the stability of the real-time supplement pressure state based on the dispersion degree according to the liquid inlet rate of the pressure relief valve.

[0030] Further, the judgment of the stability of the real-time supplement pressure state based on the dispersion degree comprises: step S431, extracting the supplement pressure oil temperatures at different times;

[0031] Step S432, judging whether the difference between the maximum value and the minimum value of the supplement pressure oil temperature meets: if the difference between the maximum value and the minimum value of the supplement pressure oil temperature is less than or equal to a preset dispersion degree predetermined threshold, entering step S434;

[0032] Step S433, if the difference between the maximum value and the minimum value of the supplement pressure oil temperature is greater than the preset dispersion degree predetermined threshold, judging whether the time difference between the time corresponding to the minimum value of the supplement pressure oil temperature and the time corresponding to the maximum value of the supplement pressure oil temperature meets: if the time difference is less than or equal to a preset time difference threshold, controlling the pressure relief valve to stop supplement pressure; if the time difference is greater than the preset time difference threshold, controlling the pressure relief valve to continue supplement pressure;

[0033] Step S434: When the pressure reducing valve maintains pressure replenishment for a time greater than or equal to the time difference threshold, determine whether the pressure replenishment oil temperature meets the following criteria: If the pressure replenishment oil temperature is less than the pressure replenishment temperature threshold, control the pressure reducing valve to continue replenishing pressure; if the pressure replenishment oil temperature is greater than the pressure replenishment temperature threshold, control the pressure reducing valve to continue replenishing pressure.

[0034] The threshold value controls the pressure reducing valve to stop pressurizing.

[0035] Furthermore, it also includes the following steps:

[0036] Step S61: When the pressure relief valve is in the pressure relief state, the pressure relief state is judged in real time based on the state of the oil at the oil outlet. The state of the oil at the oil outlet includes whether there is oil flowing out or no oil flowing out.

[0037] Step S62: If the state of the oil at the oil outlet is that oil is flowing out, control the pressure relief valve to continue to relieve pressure, and repeat step S61.

[0038] Step S63: If the oil at the oil outlet is in a state of no oil flow, based on pressure relief...

[0039] The pressure relief valve is used to determine its real-time pressure relief status based on the rate and real-time pressure relief.

[0040] Furthermore, the determination of the real-time pressure relief valve's pressure relief state based on the pressure relief rate and real-time pressure relief includes:

[0041] Step S631: Calculate the pressure relief rate of the real-time pressure relief;

[0042] Step S632: Obtain the pressure relief rate corresponding to the real-time pressure relief;

[0043] Step S633: Calculate the rate of change of the pressure relief rate, and obtain the maximum value of the rate of change and the corresponding time.

[0044] Step S634: Obtain the pressure relief rate at the end of real-time pressure relief;

[0045] Step S635: Determine the pressure relief stability state based on the preset rate of change threshold and time difference threshold.

[0046] When the rate of change is less than the rate of change threshold, a pressure relief stable state is determined;

[0047] When the rate of change is greater than or equal to the rate of change threshold, calculate the time difference between the moment corresponding to the maximum rate of change and the moment when the rate of change corresponding to the pressure relief rate at the end of the real-time pressure relief in step S634 reaches the rate of change threshold;

[0048] If the time difference is less than or equal to a time difference threshold, a pressure relief stable state is determined; if the time difference is greater than the time difference threshold, the pressure relief valve is controlled to continue pressure relief.

[0049] Further, the state of the oil at the oil outlet end includes:

[0050] Step S81, an optical sensor is arranged between the oil outlet end and the storage tank, and the optical sensor determines the state of the oil based on a preset distance threshold;

[0051] Step S82, if the oil flow at the oil outlet end is less than a preset oil flow threshold, and the optical sensor does not sense oil, it is determined that the state of the oil at the oil outlet end is that no oil flows out;

[0052] Step S83, if the oil flow at the oil outlet end is greater than or equal to a preset oil flow threshold, and the optical sensor senses oil, it is determined that the state of the oil at the oil outlet end is that oil flows out.

[0053] Further, the method further comprises the steps of:

[0054] Step S91, based on the real-time oil storage depth of the storage tank, it is determined whether the real-time oil storage depth of the storage tank meets the predetermined storage depth;

[0055] Step S92, when the real-time oil storage depth of the storage tank is greater than the predetermined storage depth of the oil in the storage tank, the oil outlet end of the storage tank is controlled to discharge oil at a constant flow rate;

[0056] Step S93, when the real-time oil storage depth of the storage tank is less than the predetermined storage depth of the oil in the storage tank, the storage tank is controlled to enter oil replenishment.

[0057] Further, the method further comprises the steps of:

[0058] Step S101, an electric field instrument is arranged in connection with a corresponding storage tank for detecting real-time data of the electric field instrument;

[0059] Step S102, preset upper and lower threshold values of data detected by the electric field instrument;

[0060] Step S103, when the real-time data of the electric field instrument does not reach a stable range of real-time data, a change rate of the real-time data is collected, and the change rate is used to determine whether the specific volume of the oil is inaccurate;

[0061] Step S104, if the change rate is less than or equal to a preset change rate threshold, it is determined that the specific volume of the oil is inaccurate; if the change rate is greater than the preset change rate threshold, it is determined that the specific volume of the oil is correct;

[0062] Step S105, comparing the real-time data upper and lower thresholds with the specific volume data of the oil liquid to obtain a stable range of the real-time data: when the real-time data is greater than or equal to the specific volume data, determining that the real-time data is out of range; and when the real-time data is less than or equal to the specific volume data, determining that the specific volume data is out of range.

[0063] The above embodiments of the present application have at least the following beneficial effects:

[0064] 1. By collecting the temperature, specific volume, flow rate and other key parameters of the oil liquid in the storage tank in real time and dynamically controlling according to these parameters, the specific volume of the oil liquid can be accurately maintained within a predetermined range, effectively avoiding problems such as poor flow of the oil liquid or imbalance of the storage tank pressure caused by abnormal specific volume, thereby improving the safety and stability of oil storage and transportation,

[0065] The defect of inaccurate control of the specific volume of the oil liquid in the prior art is solved.

[0066] 2. Real-time monitoring and automatic oil replenishment control of the oil storage depth of the storage tank are realized, the system automatically controls the oil replenishment valve to replenish oil when the real-time oil storage depth of the storage tank is lower than the normal oil storage depth, ensuring that the storage tank always maintains a suitable oil liquid depth and guaranteeing the continuity and stability of oil supply, and solving the problem of low efficiency and dependence on manual operation for oil replenishment operation of the storage tank in the prior art.

[0067] 3. A stability judgment mechanism based on dispersion and change rate is introduced to finely control the pressure relief and pressure compensation process. By monitoring the change of the temperature of the oil liquid in real time,

[0068] Combining the outflow rate and inflow rate of the pressure relief valve or pressure reducing valve, the stability of the pressure relief or pressure compensation state can be accurately judged, and reasonable control decisions can be made accordingly, avoiding pressure fluctuations of the oil liquid caused by improper operation, improving the automation level and reliability of the entire production process, and solving the problem of insufficient fine control of pressure relief and pressure compensation in the prior art, which easily causes pressure fluctuations. BRIEF DESCRIPTION OF DRAWINGS

[0069] The above and other objects, features and advantages of the exemplary embodiments of the present application will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0070] FIG. 1 is a flowchart of a grain oil production process control method according to an embodiment of the present application. DETAILED DESCRIPTION

[0071] The technical solutions in the present application will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments.

[0072] In the traditional oil tank control system, the oil state monitoring is limited to single-dimensional collection of liquid level parameters, lacking dynamic analysis of the multi-parameter coupling relationship of oil specific volume, temperature, and storage depth. The tank pressure regulation mechanism only relies on preset threshold to trigger valve action, without establishing a closed-loop feedback control based on real-time specific volume changes, resulting in viscosity fluctuations exceeding the process allowable range during oil transportation. The oil replenishment operation of the storage tank uses a fixed cycle or manual trigger mode, which cannot adaptively adjust according to the dynamic deviation of real-time storage depth from the standard storage depth, causing the risk of continuous interruption of oil supply.

[0073] For example, in a tank system using a traditional control strategy, when the oil temperature fluctuates periodically due to environmental factors, the oil specific volume value will deviate from the process set range. At this time, the pressure regulating valve only performs on-off operation according to the fixed pressure threshold, without dynamic compensation of pressure relief or pressure compensation combined with the specific volume deviation direction and amplitude. The mismatch between the tank internal pressure and the oil specific volume will cause gas-liquid two-phase flow in the oil transportation pipeline, resulting in measurement error accumulation of the flow meter. At the same time, the storage depth monitoring of the storage tank uses a mechanical floating ball sensor, whose sampling frequency is not sufficient to capture the liquid level changes in fast consumption conditions, resulting in delayed triggering of the oil replenishment command and water hammer effect caused by frequent start-stop of the oil pump.

[0074] In this application, the tank is a vertical or horizontal cylindrical steel pressure vessel that can be customized according to production capacity requirements, such as standard industrial tanks produced by manufacturers such as Zhongji Anruike.

[0075] The oil temperature sensor is directly installed on the side wall of the tank or immersed in the tank interior through a sleeve, with its temperature measuring probe in direct contact with the oil, for real-time measurement of the tank oil temperature. The model that can be used is the industrial standard PT100 platinum resistance, such as the QAE2120-0 model of Siemens brand.

[0076] The radar level gauge for measuring the standard oil storage depth of the oil and the real-time oil storage depth of the storage tank is installed on the top of the tank, with its antenna vertically downward to emit and receive radar waves to accurately measure the distance from the oil surface in the tank to the top of the tank in a non-contact manner, thereby calculating the real-time oil storage depth. The model that can be used is the VARIOFACE-RLA46 series radar level gauge of Weidmüller brand.

[0077] VARIOFACE-RLA46 series radar level gauge.

[0078] The flow meter for monitoring the oil output condition is installed on the pipeline behind the oil outlet end of the storage tank, and the flow parameter is collected by measuring the volume or mass of the oil flowing through the pipeline. The model that can be used is Emerson brand Micro Motion F025 series Coriolis mass flow meter.

[0079] The pressure relief valve is usually an electric regulating valve installed on the top of the storage tank or the pressure relief pipeline directly connected with the tank top space. When receiving the control command, its electric actuator drives the valve core to open to discharge the excess gas in the tank to achieve pressure relief. The model that can be used is Wuzhong brand ZJHP-16C electric single seat regulating valve.

[0080] The pressure reducing valve is an electric regulating valve installed on the pressure compensation pipeline leading to the tank top space. When pressure compensation is needed, it is opened to introduce the external gas source into the tank at a controlled pressure. The model that can be used is also Wuzhong ZJHP-16C series. The oil supplement valve is usually an electric ball valve installed on the oil inlet pipeline leading to the storage tank. When it is determined that the real-time oil storage depth of the storage tank needs to be increased, its electric actuator drives the ball to rotate 90 degrees to open the valve to supplement the oil from the external oil source into the tank. The model that can be used is JKV-1010 electric flange ball valve of Taiwan JKV brand.

[0081] The optical sensor is set as a pair of shot photoelectric sensors, whose emitter and receiver are oppositely installed on both sides of the pipeline between the oil outlet end and the storage tank, so that the light beam can pass through the pipeline. When the oil flows, the light beam is blocked, and the optical sensor judges that the oil outlet end has oil flowing out, otherwise it has no oil flowing out. The model that can be used is E3Z-T61-D type pair of shot photoelectric sensors of OMRON brand.

[0082] The electric field instrument is connected with the corresponding storage tank through its special detection probe, which is usually installed on the side wall of the storage tank and extends into the oil in the tank to directly collect real-time data of physical properties such as dielectric constant of the oil. In industrial applications, its function can be realized by an online densimeter. The model that can be used is L-Com5533 online densimeter of Anton Paar brand.

[0083]

[0084] All devices can be connected to the central controller of the system (for example, the model that can be used is Siemens S7-1500 series PLC) through signal cables. The controller continuously receives the oil outlet control parameters from the above-mentioned sensors, and strictly runs the judgment logic set in the claims, and finally sends the driving signal to the pressure relief valve, the pressure reducing valve and the oil supplement valve.

[0085] ​As shown in Figure 1, the application provides a grain and oil production process control method, comprising the following steps:

[0086] Step S1, real-time collection of oil product outflow control parameters of each storage tank, the oil product outflow control parameters including storage tank oil temperature, oil standard storage depth, real-time storage depth of the storage tank, specific volume of the storage tank oil, and flow rate;

[0087] Step S2, judgment of whether the specific volume of the oil in each storage tank stored oil product conforms to a predetermined range:

[0088] When the specific volume of the oil is greater than a specific volume predetermined upper deviation value, controlling the pressure relief valve of the corresponding storage tank to relieve pressure until the specific volume of the oil is less than or equal to the specific volume predetermined upper deviation value;

[0089] When the specific volume of the oil is less than a specific volume predetermined lower deviation value, controlling the pressure relief valve of the corresponding storage tank to supplement pressure until the oil is outflowed at a constant oil pressure from the oil outflow end of the corresponding storage tank;

[0090] Step S3, judgment of whether the real-time storage depth of the storage tank of each storage tank stored oil product conforms to a predetermined depth:

[0091] When the real-time storage depth of the storage tank is less than the normal storage depth of the storage tank, controlling the oil supplement valve of the corresponding storage tank to supplement oil until the real-time storage depth of the storage tank is greater than or equal to the normal storage depth of the storage tank.

[0092] The storage tank oil temperature refers to the real-time temperature of the oil in the storage tank, which can be realized by real-time data collection of a temperature sensor, and the thermal expansion state of the oil can be judged by monitoring the temperature change, so as to adjust the pressure of the storage tank to avoid abnormal specific volume of the oil.

[0093] The oil standard storage depth refers to the preset liquid level height that the oil in the storage tank should reach under normal production conditions, which can be realized by measuring the liquid level by a liquid level sensor and comparing with a preset value, to ensure that the oil storage capacity of the storage tank is within a reasonable range to maintain production continuity.

[0094] The real-time storage depth of the storage tank refers to the actual liquid level height of the current oil in the storage tank, which can be realized by real-time monitoring by an ultrasonic liquid level meter or a float type liquid level meter, and is used to dynamically judge whether oil needs to be supplemented to avoid oil supply interruption. The specific volume of the storage tank oil refers to the volume occupied by unit mass of oil, which can be calculated by measuring the oil density and combining temperature data, and the physical state of the oil can be directly reflected by specific volume monitoring, so as to trigger pressure relief or pressure supplement operation.

[0095] The pressure relief valve is a valve device for releasing the pressure inside the storage tank, which can be realized by using an electromagnetic valve or a pneumatic valve combined with a pressure sensor control. By adjusting the pressure relief, the specific volume of the oil is returned to the safe range, preventing the oil flowability from decreasing due to excessive pressure.

[0096] The pressure reducing valve is a valve device for supplementing the pressure to the storage tank, which can be realized by using a proportional regulating valve combined with a pressure feedback system. By supplementing the pressure, the stable pressure required for oil transportation is maintained, ensuring that the oil flow meets the process requirements. The oil supplement valve is a valve device for adding oil to the storage tank, which can be realized by using a flowmeter and liquid level interlocking control. When the real-time oil storage depth is lower than the preset value, the oil supplement is automatically started to avoid affecting the production process due to insufficient oil storage.

[0097] The grain oil production process control method first collects the oil control parameters of each storage tank, including the oil temperature, the standard oil storage depth, the real-time oil storage depth, the specific volume, and the flow rate. These parameters comprehensively reflect the state of the oil, providing basic data for subsequent control.

[0098] Determine whether the specific volume of the oil in each storage tank meets the predetermined range. When the specific volume of the oil is greater than the predetermined upper deviation value, control the pressure relief valve of the corresponding storage tank to release pressure until the specific volume of the oil is less than or equal to the predetermined upper deviation value. By releasing pressure, the specific volume of the oil is reduced to ensure that the oil remains in a suitable state.

[0099] When the specific volume of the oil is less than the predetermined lower deviation value, control the pressure reducing valve of the corresponding storage tank to supplement pressure until the oil is discharged at a constant pressure from the oil outlet of the corresponding storage tank. By supplementing pressure, the specific volume of the oil is increased, maintaining the appropriate state of the oil.

[0100] Determine whether the real-time oil storage depth of the oil in each storage tank meets the predetermined depth. When the real-time oil storage depth of the storage tank is less than the normal oil storage depth, control the oil supplement valve of the corresponding storage tank to supplement oil until the real-time oil storage depth of the storage tank is greater than or equal to the normal oil storage depth. This step ensures that the oil in the storage tank remains in an appropriate storage amount.

[0101] As a preferred embodiment, the scheme of the present application is implemented as follows:

[0102] On the grain oil production line, multiple storage tanks are set up to store different types of oil. Each storage tank is equipped with a temperature sensor, a liquid level sensor, a specific volume measuring device, and a flowmeter to collect real-time oil temperature, oil storage depth, specific volume, and flow data. At the same time, the storage tank is also installed with a pressure relief valve, a pressure reducing valve, and an oil supplement valve.

[0103] The control parameters of the oil output of each tank are continuously monitored. For example, for a tank containing soybean oil, the system collects data every 5 seconds. Suppose at a certain time, the system collects the oil temperature of the tank as 25℃, the standard oil storage depth of the oil as 5 meters, the real-time oil storage depth as 4.8 meters, the specific volume of the oil as 1.1, and the flow rate as 100 liters / minute.

[0104] First, it is determined whether the specific volume of the oil is within a predetermined range. Suppose the predetermined specific volume range is 0.9-1.05. Since the current specific volume 1.1 is greater than the upper limit 1.05, the system immediately starts the pressure relief valve to relieve pressure. During the pressure relief process, the system continuously monitors the change in specific volume, and when the specific volume drops to 1.05 or below, the pressure relief valve is closed.

[0105] The oil storage depth is checked. Since the real-time oil storage depth 4.8 meters is less than the normal oil storage depth 5 meters, the system starts the oil supplement valve to supplement oil. During the oil supplement process, the system continuously monitors the oil storage depth, and when the depth reaches or exceeds 5 meters, the oil supplement is stopped.

[0106] In this way, the oil can be continuously maintained in an ideal state, ensuring the stability of the production process and the quality of the oil.

[0107] The application further proposes controlling the pressure relief valve of the corresponding tank to relieve pressure, including: receiving a pressure relief instruction for pressure relief; determining the pressure relief state of the pressure relief valve, the pressure relief state including a pressure relief state and a non-pressure relief state; when the pressure relief valve is in the non-pressure relief state, according to the pressure relief instruction, determining whether the pressure relief oil temperature is greater than or equal to a pressure relief temperature threshold value, and if so, controlling the pressure relief valve to open to relieve pressure; when the pressure relief valve is in the pressure relief state, according to the pressure relief instruction, determining whether the pressure relief oil temperature is less than the pressure relief temperature threshold value, and if so, controlling the pressure relief valve to open to relieve pressure; repeating the above steps, and when the pressure relief valve is in the pressure relief state, collecting the pressure relief oil temperature of the oil at different time periods at different times, and based on the dispersion, determining the stability of the real-time pressure relief state according to the outflow rate of the pressure relief valve.

[0108] The pressure relief temperature threshold value can be set to 60℃, the dispersion predetermined threshold value can be set to 5℃, and the time difference threshold value can be set to 30 seconds. The pressure relief state of the pressure relief valve is monitored in real time by a pressure sensor, and the pressure relief oil temperature is collected by a temperature sensor. The pressure relief instruction is generated by a central controller according to the specific volume deviation value and is sent to the pressure relief valve control module. The outflow rate is obtained by measuring the outflow of the oil per unit time during the pressure relief process by a flow meter.

[0109] Specifically, the control process of the pressure relief valve is divided into three stages. First, after the central controller generates a pressure relief instruction, the pressure relief valve control module detects the current pressure relief state. If the pressure relief valve is in the non-pressure relief state, it needs to be determined whether the pressure relief oil temperature reaches the 60℃ threshold. If the condition is met, the pressure relief valve is opened. Second, during the pressure relief process, the pressure relief oil temperature is continuously monitored. If the temperature is lower than 60℃, the pressure relief valve remains open. Finally, during the opening of the pressure relief valve, the pressure relief oil temperature data is collected every 10 seconds, and the maximum and minimum temperature difference of the adjacent three time points is calculated. If the difference exceeds 5℃, it is further determined whether the interval between the maximum and minimum temperature corresponding time exceeds 30 seconds. If it does not exceed, the pressure relief valve is immediately closed. If it exceeds, the pressure relief continues. When the pressure relief duration reaches 30 seconds, it is detected again whether the temperature is higher than 60℃. If it is lower, the pressure relief is stopped. Through the double judgment of temperature threshold and dispersion, the unstable pressure relief process caused by sudden temperature change is avoided, and the pressure relief flow is verified through the liquid rate data to ensure the accuracy and stability of the pressure relief operation.

[0110] The pressure relief flow is verified through the liquid rate data to ensure the accuracy and stability of the pressure relief operation.

[0111] As a preferred embodiment, the scheme of the present application is implemented as follows:

[0112] The pressure relief valve of the corresponding storage tank is controlled to relieve pressure, including the following steps:

[0113] A pressure relief instruction for pressure relief is received. The pressure relief instruction can be automatically generated by the control system according to the specific volume change of the oil in the storage tank, or manually input by the operator.

[0114] The pressure relief state of the pressure relief valve is determined. The pressure relief state includes the pressure relief state and the non-pressure relief state. The determination can be achieved by detecting the switch position of the pressure relief valve or the flow in the pressure relief pipeline.

[0115] When the pressure relief valve is in the non-pressure relief state, according to the pressure relief instruction, it is determined whether the pressure relief oil temperature is greater than or equal to the pressure relief temperature threshold. The pressure relief temperature threshold can be set to 60℃. If the pressure relief oil temperature is greater than or equal to 60℃, the pressure relief valve is controlled to open for pressure relief. The opening can be achieved by driving the pressure relief valve to open through an electric actuator.

[0116] When the pressure relief valve is in the pressure relief state, according to the pressure relief instruction, it is determined whether the pressure relief oil temperature is less than the pressure relief temperature threshold. If the pressure relief oil temperature is less than 60℃, the pressure relief valve is controlled to open for pressure relief.

[0117] The above judgment steps are repeated. When the pressure relief valve is in the pressure relief state, the pressure relief oil temperature of the oil at different time periods is collected. The temperature data can be collected every 10 seconds. And according to the outflow rate of the pressure relief valve, the stability of the real-time pressure relief state is judged based on the dispersion. The outflow rate can be obtained by measuring with a flowmeter, and the dispersion can be represented by calculating the standard deviation of the temperature data.

[0118] The application further proposes to judge the stability of the real-time pressure relief state based on the dispersion, including extracting the pressure relief oil temperature at different times; judging whether the difference between the maximum value and the minimum value of the pressure relief oil temperature meets the preset dispersion threshold value; if not, further judging whether the time difference between the time corresponding to the maximum value and the minimum value exceeds the threshold value, thereby controlling the opening and closing of the pressure relief valve; if so, after the pressure relief time reaches the threshold value, controlling the pressure relief valve according to the comparison result of the pressure relief oil temperature and the pressure relief temperature threshold value.

[0119] Among them, when extracting the pressure relief oil temperature, the temperature data at multiple time points during the pressure relief process is continuously collected by the temperature sensor, and the data is stored to the control unit. When judging the difference between the maximum value and the minimum value, the preset dispersion threshold value is set according to the type of oil and the specification of the storage tank, for example, set to 5℃. If the difference exceeds the threshold value, the time difference between the time corresponding to the maximum value and the minimum value is further calculated, for example, the time difference threshold value is set to 10 minutes. If the time difference is less than or equal to the threshold value, it indicates that the temperature fluctuation is concentrated in a short time, and the pressure relief needs to be stopped immediately; if the time difference is greater than the threshold value, the pressure relief continues. When the pressure relief time reaches the time difference threshold value, the pressure relief oil temperature is detected again, if the temperature is still higher than the pressure relief temperature threshold value, the pressure relief is maintained; if it is lower than the threshold value, the pressure relief valve is closed.

[0120] During the pressure relief process, the temperature sensor collects the pressure relief oil temperature in real time and transmits it to the control unit. The control unit extracts the temperature data of the continuous time period, and calculates the difference between the maximum value and the minimum value. For example, if the temperature data collected is reduced from 85℃ to 78℃ within 30 minutes, the difference is 7℃, which exceeds the preset threshold value of 5℃, then the time difference between the time corresponding to the maximum value and the minimum value is further judged. If the time difference is 8 minutes, which is less than the threshold value of 10 minutes, it indicates that the sudden temperature drop may be caused by abnormal factors, and the pressure relief needs to be stopped immediately to avoid out-of-control pressure; if the time difference is 15 minutes, the pressure relief continues. When the pressure relief duration reaches 10 minutes, the temperature is detected again, if the temperature is still higher than the pressure relief temperature threshold value of 80℃, the pressure relief continues; if the temperature drops below 80℃, the pressure relief valve is closed. Through the above steps, combined with the double judgment of dispersion and time difference, the pressure relief operation is dynamically adjusted to ensure that the pressure relief process is stable and meets the process requirements.

[0121] As a preferred embodiment, the scheme of the application is implemented as follows:

[0122] Extract the pressure relief oil temperature at different time. Determine whether the difference between the maximum and minimum pressure relief oil temperature meets: if the difference between the maximum and minimum pressure relief oil temperature is less than or equal to the preset dispersion threshold, proceed to the next step. If the difference between the maximum and minimum pressure relief oil temperature is greater than the preset dispersion threshold, determine whether the time difference between the time corresponding to the minimum pressure relief oil temperature and the time corresponding to the maximum pressure relief oil temperature meets:

[0123] : if the time difference is less than or equal to the preset time difference threshold, control the pressure relief valve to stop pressure relief; if the time difference is greater than the preset time difference threshold, control the pressure relief valve to continue pressure relief. When the pressure relief valve maintains pressure relief for greater than or equal to the time difference threshold, determine whether the pressure relief oil temperature meets: if the pressure relief oil temperature is greater than or equal to the pressure relief temperature threshold, control the pressure relief valve to continue pressure relief; if the pressure relief oil temperature is less than the pressure relief temperature threshold, control the pressure relief valve to stop pressure relief.

[0124] For example, the dispersion threshold can be set to 5℃, the time difference threshold to 10 minutes, and the pressure relief temperature threshold to 60℃. In actual operation, first extract the pressure relief oil temperature data every minute within the last 30 minutes. If the difference between the maximum and minimum temperatures does not exceed 5℃, proceed directly to the subsequent judgment step. If the temperature difference exceeds 5℃, further determine the time interval between the times corresponding to the maximum and minimum temperatures. If the time interval does not exceed 10 minutes, stop pressure relief; if it exceeds 10 minutes, continue pressure relief. When the pressure relief duration exceeds 10 minutes, if the current pressure relief oil temperature is higher than 60℃, continue pressure relief; if it is lower than 60℃, stop pressure relief.

[0125] The application further proposes controlling the pressure relief valve of the corresponding storage tank to perform pressure compensation, including: receiving a pressure compensation instruction; determining the pressure compensation state of the pressure relief valve, including a pressure compensation state and a non-pressure compensation state; when the pressure relief valve is in the non-pressure compensation state, determining whether the pressure compensation oil temperature is greater than the pressure compensation temperature threshold according to the pressure compensation instruction, and if so, controlling the pressure relief valve to open to perform pressure compensation; when the pressure relief valve is in the pressure compensation state, determining whether the pressure compensation oil temperature is less than the pressure compensation temperature threshold according to the pressure compensation instruction, and if so, controlling the pressure relief valve to open to perform pressure compensation; repeating the above steps, and when the pressure relief valve is in the pressure compensation state, collecting the pressure compensation oil temperature of the oil at different time periods, and determining the stability of the real-time pressure compensation state based on the dispersion and the inlet rate of the pressure relief valve.

[0126] The reception of the pressure compensation instruction realizes data interaction with the central control system through a preset communication protocol, ensuring the real-time nature of the instruction transmission. The pressure compensation state determination combines a pressure sensor and a valve state feedback module. The pressure sensor monitors the internal pressure value of the storage tank in real time, and the valve state feedback module determines the pressure compensation state of the pressure relief valve according to the pressure value and the valve state.

[0127] The state feedback module obtains the opening or closing state of the pressure reducing valve. The judgment of the temperature of the pressure compensation oil is obtained by collecting the temperature data of the oil through the temperature sensor and comparing it with the preset pressure compensation temperature threshold, which is set to the interval of 45°C to 55°C according to the type of oil. The dispersion judgment is obtained by calculating the difference between the maximum and minimum values of the pressure compensation oil temperature. When the difference exceeds the preset dispersion threshold, the time difference threshold is adjusted dynamically. The dispersion threshold is set to 5°C, and the time difference threshold is set to 30 seconds.

[0128] When the pressure reducing valve is in the non-pressure compensation state, if the temperature of the pressure compensation oil exceeds the upper limit of the pressure compensation temperature threshold, the pressure reducing valve is opened to avoid the abnormal decrease of the specific volume of the oil caused by high temperature. When the pressure reducing valve is in the pressure compensation state, if the temperature of the pressure compensation oil is lower than the lower limit of the pressure compensation temperature threshold, the pressure reducing valve is maintained in the open state to prevent pressure fluctuation caused by sudden temperature drop. When the pressure compensation state is repeatedly executed, the temperature dispersion of the pressure compensation oil is calculated by periodically collecting the temperature data. When the dispersion exceeds the threshold and the time difference is less than 30 seconds, the pressure compensation is stopped to eliminate the interference of short-term temperature mutation; when the time difference exceeds 30 seconds, the pressure compensation is continued to deal with the long-term temperature trend. Through the correlation analysis of the liquid inlet rate and the temperature dispersion, the duration of the pressure compensation operation is dynamically adjusted to ensure the stability of the pressure compensation process and the specific volume of the oil within the predetermined range.

[0129] As a preferred embodiment, the scheme of the present application is implemented as follows:

[0130] The control of the pressure reducing valve of the corresponding storage tank for pressure compensation includes the following steps:

[0131] Firstly, a pressure compensation instruction for pressure compensation is received. This pressure compensation instruction can be automatically generated by the control system according to the change of the specific volume of the oil in the storage tank, or it can be manually input by the operator.

[0132] Secondly, the pressure compensation state of the pressure reducing valve is judged. The pressure compensation state of the pressure reducing valve includes two states: pressure compensation state and non-pressure compensation state.

[0133] When the pressure reducing valve is in the non-pressure compensation state, according to the received pressure compensation instruction, it is judged whether the temperature of the pressure compensation oil is greater than the pressure compensation temperature threshold. If the temperature of the pressure compensation oil is greater than the pressure compensation temperature threshold, the pressure reducing valve is controlled to open for pressure compensation. The pressure compensation temperature threshold can be preset according to the characteristics of different oil products, for example, it can be set to 20°C.

[0134] When the pressure reducing valve is in the pressure compensation state, according to the pressure compensation instruction, it is judged whether the temperature of the pressure compensation oil is less than the pressure compensation temperature threshold. If the temperature of the pressure compensation oil is less than the pressure compensation temperature threshold, the pressure reducing valve is controlled to open for pressure compensation.

[0135] The above judgment steps are repeated. When the pressure reducing valve is in the pressure compensation state, the pressure compensation oil temperature of the oil at different time periods is collected. The temperature data can be collected every 5 minutes. At the same time, according to the inlet flow rate of the pressure reducing valve, the stability of the real-time pressure compensation state is judged based on the dispersion. The inlet flow rate can be measured by a flow meter, and the dispersion can be represented by calculating the standard deviation of the temperature data.

[0136] The application further proposes that the stability of the real-time pressure compensation state based on the dispersion includes: extracting the pressure compensation oil temperature at different times; judging whether the difference between the maximum value and the minimum value of the pressure compensation oil temperature meets: if the difference between the maximum value and the minimum value of the pressure compensation oil temperature is less than or equal to the preset dispersion predetermined threshold, then entering the subsequent step; if the difference between the maximum value and the minimum value of the pressure compensation oil temperature is greater than the preset dispersion predetermined threshold, then judging whether the time difference between the time corresponding to the minimum value and the time corresponding to the maximum value of the pressure compensation oil temperature meets: if the time difference is less than or equal to the preset time difference threshold, controlling the pressure reducing valve to stop pressure compensation; if the time difference is greater than the preset time difference threshold, controlling the pressure reducing valve to continue pressure compensation; when the pressure reducing valve maintains pressure compensation for greater than or equal to the time difference threshold, judging whether the pressure compensation oil temperature meets: if the pressure compensation oil temperature is less than the pressure compensation temperature threshold, controlling the pressure reducing valve to continue pressure compensation; if the pressure compensation oil temperature is greater than the pressure compensation temperature threshold, controlling the pressure reducing valve to stop pressure compensation.

[0137] The dispersion predetermined threshold is set to 0.5°C, and the time difference threshold is set to 10 seconds. The difference between the maximum value and the minimum value of the pressure compensation oil temperature is calculated by continuously collecting temperature data at least three times. The pressure compensation temperature threshold is set according to the type of oil, for example, the soybean oil is set to 45°C, and the rapeseed oil is set to 50°C. The collection interval of the pressure compensation oil temperature is 2 seconds, which ensures the real-time nature of the data.

[0138] During the pressure compensation process, the temperature sensor collects oil temperature data at a period of 2 seconds and records the corresponding time. When the difference between the maximum value and the minimum value of the temperature data collected three times in a row exceeds 0.5°C, the interval of the time corresponding to the extreme value is further compared. If the extreme value interval is within 10 seconds, it indicates that the temperature fluctuation is concentrated, and the pressure compensation needs to be stopped immediately to avoid local overheating; if the extreme value interval exceeds 10 seconds, the pressure compensation is allowed to continue. After the pressure compensation continues for 10 seconds, the temperature is detected again to see if it is lower than the set threshold. If it is still lower than the threshold, the pressure compensation is maintained, otherwise the operation is terminated. Through the double judgment of dispersion and time difference, normal fluctuation and abnormal fluctuation are effectively distinguished, avoiding misoperation caused by instantaneous temperature change, and ensuring the continuity of the pressure compensation operation.

[0139] As a preferred embodiment, the scheme of the application is implemented as follows:

[0140] The stability of the real-time pressure compensation state based on the dispersion includes the following steps:

[0141] Extract the temperature of the pressure compensation oil at different time. For example, collect the temperature data of the pressure compensation oil every 5 minutes, and collect for 1 hour to obtain 12 temperature data points.

[0142] Determine whether the difference between the maximum and minimum values of the pressure compensation oil temperature meets the preset condition. Specifically, calculate the maximum and minimum values of the 12 temperature data points, and if the difference between the two is less than or equal to the preset dispersion threshold (e.g., 2°C), proceed to the next step; if it is greater than the preset dispersion threshold, proceed to the next step.

[0143] Further, when the difference between the maximum and minimum values of the pressure compensation oil temperature is greater than the preset dispersion threshold, determine whether the time difference between the time corresponding to the minimum value and the time corresponding to the maximum value of the pressure compensation oil temperature meets the preset condition. For example, if the time difference is less than or equal to the preset time difference threshold (e.g., 30 minutes), control the pressure reducing valve to stop pressure compensation; if the time difference is greater than the preset time difference threshold, control the pressure reducing valve to continue pressure compensation.

[0144] When the pressure reducing valve maintains pressure compensation for greater than or equal to the time difference threshold, determine whether the pressure compensation oil temperature meets the preset condition. Specifically, if the pressure compensation oil temperature is less than the pressure compensation temperature threshold (e.g., 25°C), control the pressure reducing valve to continue pressure compensation; if the pressure compensation oil temperature is greater than the pressure compensation temperature threshold, control the pressure reducing valve to stop pressure compensation.

[0145] The present application further proposes that when the pressure relief valve is in a pressure relief state, the real-time pressure relief state is judged based on the state of the oil at the oil outlet, which includes oil flowing out or no oil flowing out; if the state of the oil at the oil outlet is oil flowing out, the pressure relief valve is controlled to continue pressure relief, and the judgment step is repeated; if the state of the oil at the oil outlet is no oil flowing out, the real-time pressure relief state of the pressure relief valve is judged based on the pressure relief rate and the real-time pressure relief pressure.

[0146] The detection of the state of the oil at the oil outlet is achieved by an optical sensor, which is arranged between the oil outlet and the storage tank, and the state of the oil flow is determined based on an oil flow threshold. The pressure relief rate is obtained by calculating the rate of change of the real-time pressure relief pressure, and the judgment condition of the pressure relief stable state is established based on the maximum value of the rate of change of the pressure relief rate and the pressure relief rate at the end of the real-time pressure relief. The control logic of the pressure relief valve is achieved by presetting the threshold of the rate of change and the threshold of the time difference, and when the rate of change of the pressure relief rate exceeds the threshold, the pressure relief process is determined to continue or not based on the time difference.

[0147] During the pressure relief process, the optical sensor monitors the oil flow at the oil outlet in real time. When the flow is lower than a threshold value, it is determined that the oil flow has stopped, and the pressure relief rate analysis phase is entered. Real-time data of the pressure relief pressure is collected and the rate of change is calculated. By comparing the maximum value of the rate of change with a preset threshold value, the dynamic stability of the pressure relief process is determined. If the rate of change exceeds the threshold value but the time difference between the corresponding time and the end time of the pressure relief is within the allowable range, it is determined that the pressure relief has reached a stable state; if the time difference exceeds the range, the pressure relief continues until the conditions are met. This process replaces manual judgment through automated data collection and calculation, ensuring accurate termination of the pressure relief operation and avoiding deviations in oil specific volume caused by insufficient or excessive pressure relief.

[0148] As a preferred embodiment, the scheme of the present application is implemented as follows:

[0149] When the pressure relief valve is in the pressure relief state, real-time pressure relief state judgment is performed based on the state of the oil at the oil outlet. The state of the oil at the oil outlet includes oil flowing out or no oil flowing out. Specifically, a photoelectric sensor is installed at the oil outlet to detect whether oil is flowing out.

[0150] If the state of the oil at the oil outlet is oil flowing out, the pressure relief valve is controlled to continue pressure relief, and the judgment of the state of the oil at the oil outlet is repeated. For example, the state of the oil at the oil outlet is detected every 5 seconds.

[0151] If the state of the oil at the oil outlet is no oil flowing out, real-time pressure relief state judgment of the pressure relief valve is performed based on the pressure relief rate and the real-time pressure relief pressure. Specifically, the pressure sensor monitors the pressure change in the pressure relief process in real time, and calculates the pressure relief rate. When the pressure relief rate is lower than a preset threshold value (such as 0.1 MPa / min) and the real-time pressure relief pressure reaches the target pressure, it is determined that the pressure relief is complete, and the pressure relief valve is closed.

[0152] The present application further proposes that the real-time pressure relief state judgment of the pressure relief valve based on the pressure relief rate and the real-time pressure relief pressure includes: calculating the pressure relief rate of the real-time pressure relief pressure; obtaining the pressure relief rate corresponding to the real-time pressure relief pressure; calculating the rate of change of the pressure relief rate to obtain the maximum value of the rate of change and the time corresponding thereto; obtaining the pressure relief rate at the end of the real-time pressure relief; determining the stable state of the pressure relief according to the preset rate of change threshold value and the time difference threshold value: when the rate of change is less than the rate of change threshold value, it is determined that the pressure relief is in a stable state; when the rate of change is greater than or equal to the rate of change threshold value, the time difference between the time corresponding to the maximum value of the rate of change and the time when the rate of change corresponding to the pressure relief rate at the end of the real-time pressure relief reaches the rate of change threshold value is calculated; if the time difference is less than or equal to the time difference threshold value, it is determined that the pressure relief is in a stable state; if the time difference is greater than the time difference threshold value, the pressure relief valve is controlled to continue pressure relief.

[0153] The calculation of the pressure relief rate is performed by collecting real-time pressure relief pressure data through a pressure sensor and calculating the pressure change amount per unit time using a difference method. The pressure relief rate corresponding to the real-time pressure relief pressure is achieved by establishing a pressure-rate mapping relationship table, which is generated based on historical data fitting.

[0154] Specifically, during the pressure relief process, when it is detected that no oil flows out of the oil outlet, the pressure sensor continuously collects pressure relief pressure data. The pressure relief rate is calculated every second, and the rate change trend in the last 5 seconds is analyzed through a sliding window. If the maximum change rate in the window is less than 0.3MPa / s, it is determined that the pressure relief process has entered a stable state, and the pressure relief can be safely stopped. When the change rate exceeds the threshold, the system automatically compares the time difference between the maximum change rate time and the pressure relief end time. If the time difference is within 2 seconds, it indicates that the pressure fluctuation is a normal decay process; if it exceeds 2 seconds, it is determined that there is an abnormal pressure fluctuation, and the pressure relief needs to continue until the stable condition is met. This judgment mechanism quantitatively analyzes the dynamic characteristics of pressure change, avoids misjudgment caused by relying on a single state signal, and ensures that the termination time of the pressure relief operation accurately matches the stable state of the pressure.

[0155] As a preferred embodiment, the scheme of the present application is implemented as follows:

[0156] The real-time pressure relief state of the pressure relief valve is judged based on the pressure relief rate and the real-time pressure relief pressure, including the following steps:

[0157] The pressure relief rate of the real-time pressure relief pressure is calculated. Specifically, the pressure relief rate can be calculated by measuring the change amount of the pressure relief pressure per unit time. For example, the pressure relief pressure is measured every second, and the difference between the adjacent two measurement values is calculated, i.e. the pressure relief rate is obtained.

[0158] The pressure relief rate corresponding to the real-time pressure relief pressure is obtained. This step can be achieved by querying a pre-established corresponding relationship table of pressure relief pressure and pressure relief rate. The corresponding relationship table can be obtained based on historical data or theoretical calculation.

[0159] Further, the change rate of the pressure relief rate is calculated to obtain the maximum change rate and the corresponding time. The difference between the adjacent two times of the pressure relief rate can be calculated, and the change rate of the pressure relief rate is obtained by dividing the time interval. Then, all the calculated change rates are compared to find the maximum value and the corresponding time.

[0160] Obtain the depressurization rate at the end of the real-time depressurization process. This data can be obtained through a real-time monitoring system.

[0161] The pressure relief stability state is determined based on preset rate of change and time difference thresholds. The specific determination process is as follows:

[0162] When the rate of change is less than the rate of change threshold, the pressure relief is considered to be in a stable state. For example, if the preset rate of change threshold is 0.1 MPa / s², the pressure relief is considered to be stable when the calculated rate of change is less than 0.1 MPa / s².

[0163] When the rate of change is greater than or equal to the rate of change threshold, the time difference between the moment corresponding to the maximum rate of change and the moment when the rate of change corresponding to the pressure relief rate at the end of real-time pressure relief reaches the rate of change threshold is calculated. If this time difference is less than or equal to the time difference threshold, a stable pressure relief state is determined; if the time difference is greater than the time difference threshold, the pressure relief valve is controlled to continue pressure relief. For example, assuming the time difference threshold is set to 10 seconds, if the calculated time difference is less than or equal to 10 seconds, the pressure relief state is considered stable; otherwise, the pressure relief operation continues.

[0164] This application further proposes to install an optical sensor between the oil outlet and the storage tank. The optical sensor determines the oil state based on a preset distance threshold. If the oil flow rate at the oil outlet is less than the preset oil flow rate threshold, the optical sensor does not detect the oil, and the state of the oil at the oil outlet is determined to be no oil flow. If the oil flow rate at the oil outlet is greater than or equal to the preset oil flow rate threshold, the optical sensor detects the oil, and the state of the oil at the oil outlet is determined to be oil flow.

[0165] The optical sensor is installed on the outer wall or inside of the pipe between the oil outlet and the storage tank. It detects the presence of oil by emitting a light beam and receiving the reflected signal. The distance threshold is set according to the pipe diameter and the oil flow pattern; for example, when the pipe inner diameter is 10 cm, the distance threshold can be set to 2 cm. The oil flow rate threshold is determined experimentally; for example, when the flow rate is less than 5 liters per minute, the oil cannot cover the detection area of ​​the optical sensor. The optical sensor is connected to the control system. When the flow rate data is inconsistent with the optical detection result, the optical sensor's judgment result is given priority.

[0166] Specifically, the optical sensor forms a continuous detection area within the pipeline. When the oil flow rate reaches a threshold, the liquid level covers the detection area, and the intensity of the reflected light signal exceeds a preset value, triggering a determination that oil is flowing out. When the flow rate is below the threshold, the liquid level cannot maintain continuous coverage, and the reflected signal exhibits intermittent fluctuations; at this point, it is determined that no oil is flowing out. This determination logic, along with the flow threshold, forms a dual verification mechanism to avoid measurement errors from a single flow sensor in the low flow range. For example, during pressure relief, if the flow sensor displays a flow rate of 4 liters per minute, and the optical sensor does not detect a continuous liquid level, the pressure relief valve will immediately stop to prevent equipment damage caused by idling.

[0167] As a preferred embodiment, the solution of this application is implemented as follows: An optical sensor is installed on the outside of the oil pipeline between the oil outlet and the storage tank. The transmitting end and receiving end of the optical sensor are located on both sides of the pipeline and are kept horizontally aligned. The optical sensor judges the state based on a preset oil flow rate threshold, which is set to 0.5 cubic meters per hour. When the oil flow rate at the oil outlet is lower than this threshold, the oil flow velocity in the pipeline is insufficient to form a continuous liquid surface. At this time, the optical path of the optical sensor is not blocked, the receiving end detects a complete light signal, and it is determined that there is no oil flowing out. When the oil flow rate reaches or exceeds the threshold, the oil forms a stable flow and continuously covers the pipeline cross-section. The light signal is periodically or continuously blocked, the receiving end detects a light intensity attenuation signal, and it is determined that there is oil flowing out.

[0168] This application further proposes to install an optical sensor between the oil outlet and the storage tank. The optical sensor determines the oil state based on a preset distance threshold. If the oil flow rate at the oil outlet is less than the preset oil flow rate threshold, the optical sensor does not detect the oil, and the state of the oil at the oil outlet is determined to be no oil flow. If the oil flow rate at the oil outlet is greater than or equal to the preset oil flow rate threshold, the optical sensor detects the oil, and the state of the oil at the oil outlet is determined to be oil flow.

[0169] The optical sensor is installed outside the connecting pipe between the oil outlet and the storage tank, with its detection direction perpendicular to the oil flow direction. The optical sensor emits a light beam.

[0170] The presence of oil is determined by receiving reflected signals, and the emission frequency of the light beam is related to the oil flow rate threshold. When the oil flow rate reaches the threshold, the oil flowing through the detection area of ​​the optical sensor will generate a continuous reflected signal; when the flow rate is below the threshold, the reflected signal is interrupted due to the discontinuous oil flow. The oil flow rate threshold is dynamically adjusted according to the depressurization rate of the storage tank and the inner diameter of the pipeline. For example, when the inner diameter of the pipeline is 50 mm, the oil flow rate threshold is set to 10 liters per minute.

[0171] The beam coverage area of ​​the optical sensor coincides with the oil flow path inside the pipeline. When the oil flow rate reaches a threshold, a stable reflective surface forms on the flowing oil, and the optical sensor continuously receives the reflected signal, determining that oil is flowing out. When the flow rate is below the threshold, the oil flow becomes intermittent, and the reflected signal is intermittently interrupted, indicating that no oil is flowing out. By dynamically adjusting the flow rate threshold, the system can adapt to changes in the oil state at different pressure relief stages. For example, when the flow rate is high at the beginning of pressure relief, the threshold is set to 12 liters per minute; when the flow rate decreases in the later stages of pressure relief, the threshold is adjusted to 8 liters per minute. This determination result is directly fed back to the pressure relief valve control module to trigger pressure relief rate adjustment or pressure relief termination operations, thereby ensuring the stability of the pressure relief process.

[0172] A high-precision liquid level sensor is installed on the side wall of the storage tank, continuously collecting oil depth data with millimeter-level resolution. When the liquid level sensor detects an oil depth of 2.5 meters, the constant flow control module of the oil outlet pipeline is activated via the PLC controller. This module includes a turbine flow meter and a proportional control valve, which stabilizes the oil flow rate at 8 cubic meters per hour. When the liquid level sensor detects an oil depth below 2.2 meters, the PLC controller sends a start command to the replenishment pump, which injects oil through a DN50 pipeline at a rate of 10 cubic meters per hour. Simultaneously, the liquid level sensor feeds back real-time data to the control system every 30 seconds until the oil depth returns to the standard value of 2.5 meters.

[0173] This application further proposes setting up an electric field meter connected to a corresponding storage tank for detecting real-time data from the electric field meter; preset upper and lower thresholds for the data detected by the electric field meter; and when the real-time data from the electric field meter...

[0174] When the real-time data is not within a stable range, the rate of change of the real-time data is collected, and the rate of change is used to determine whether the specific volume of the oil is inaccurate. If the rate of change is less than or equal to a preset rate of change threshold, the specific volume of the oil is determined to be inaccurate. If the rate of change is greater than the preset rate of change threshold, the specific volume of the oil is determined to be in line with the threshold. The upper and lower thresholds of the real-time data are compared with the specific volume data of the oil to obtain the stable range of the real-time data: when the real-time data is greater than or equal to the specific volume data, the inaccurate range of the real-time data is determined; when the real-time data is less than or equal to the specific volume data, the inaccurate range of the specific volume data is determined.

[0175] The electric field meter detects the dielectric constant of oil by measuring changes in the electromagnetic field. It is installed on the outer wall of the storage tank or in a non-contact area inside to avoid interfering with oil flow. The upper and lower thresholds for the data are set according to the oil type and historical stable operating conditions; for example, the threshold range for rapeseed oil is 1.5-2.3 kV / m. The rate of change threshold is determined experimentally; when the oil flow rate is 5 m³ / h, the rate of change threshold is set to 0.05 / s. The real-time data stability range is determined by dynamically comparing the linear relationship between the electric field data and the specific volume data; for example, a misalignment judgment is triggered when the correlation coefficient between the electric field data and the specific volume data is lower than 0.9.

[0176] The electric field meter collects real-time data on the dielectric properties of the oil in the storage tank and determines whether the data is abnormal by using a preset electric field strength threshold range. When the detected data exceeds the threshold, the system automatically calculates the rate of change. If the rate of change is lower than the set threshold, it indicates that the electric field meter data is drifting or that a sudden change in oil composition has caused inaccurate specific volume, triggering a calibration procedure or alarm. If the rate of change is higher than the threshold, it is determined to be a normal operating condition fluctuation, and the current control strategy is maintained. By cross-validating the electric field data and the specific volume data, when the electric field data is consistently higher than the corresponding threshold of the specific volume data, it is determined to be a sensor malfunction or oil contamination; when the electric field data is lower than the corresponding threshold of the specific volume data, it is determined to be a parameter mismatch in the specific volume calculation model. This achieves the self-verification function of the monitoring system, avoiding misjudgments caused by monitoring a single parameter, and at the same time, the robustness of the control system is improved through dynamic threshold adjustment.

[0177] As a preferred embodiment, the solution of this application is implemented as follows: An electric field meter is installed on the top of the storage tank, and the electric field meter is connected to the storage tank control system through a data acquisition module. The electric field meter detects the dielectric constant and electric field strength data of the oil in the storage tank in real time, with the detection frequency set to once per second. The preset upper threshold for electric field strength data is 5kV / m, the lower threshold is 3kV / m, the upper threshold for dielectric constant is 2.8, and the lower threshold is 2.3. When the electric field meter detects that the real-time electric field strength data exceeds the upper and lower threshold ranges three times consecutively, the change rate calculation program is started. Specifically, the change rate per second is obtained by calculating the absolute value of the difference between the data of two adjacent acquisition cycles. If the change rate is less than or equal to 0.1kV / m·s, the oil specific volume is determined to be inaccurate, triggering the control system to issue a specific volume calibration command; if the change rate is greater than 0.1kV / m·s, the specific volume is determined to meet the requirements. The real-time electric field data is further compared with the standard specific volume curve of the oil in the storage tank. When the electric field strength data is continuously higher than the corresponding value of the standard specific volume curve, it is determined that the real-time data is in the inaccurate range. At this time, the pressure relief valve is activated to perform dynamic pressure compensation. When the dielectric constant data is continuously lower than the corresponding value of the standard specific volume curve, it is determined that the specific volume data is in the inaccurate range. At this time, the oil replenishment valve is activated to replenish the oil.

[0178] Through the above technical solution, this application effectively solves the problem that traditional storage tank systems cannot monitor the dynamic changes of oil physical parameters in real time. By correlating the data from the electric field meter with the specific volume parameter, abnormal oil conditions can be automatically identified, avoiding control deviations caused by the lag in manual judgment. Based on the joint judgment mechanism of the rate of change threshold and the data stability range, the accuracy of specific volume misalignment detection is significantly improved, preventing misjudgments caused by sensor drift or environmental interference. This solution achieves closed-loop control of the storage tank oil parameters, ensuring that the specific volume data is always within the stable range required by the process.

[0179] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method for controlling a grain-oil production process, characterized by, The method comprises the following steps: Step S1, collecting oil control parameters of oil products stored in each tank in real time, wherein the oil control parameters comprise oil temperature, standard oil storage depth, real-time oil storage depth, specific volume and flow rate of oil in the tank; Step S2, judging whether the specific volume of oil in each tank meets a predetermined range: When the specific volume of oil is greater than a specific volume predetermined upper deviation value, controlling a pressure relief valve of the corresponding tank to relieve pressure until the specific volume of oil is less than or equal to the specific volume predetermined upper deviation value; When the specific volume of oil is less than a specific volume predetermined lower deviation value, controlling a pressure relief valve of the corresponding tank to relieve pressure until the oil outlet of the corresponding tank is controlled to discharge oil at a constant oil pressure; Step S3, judging whether the real-time oil storage depth of oil products stored in each tank meets a predetermined depth: When the real-time oil storage depth of the tank is less than a normal oil storage depth of the tank, controlling a refueling valve of the corresponding tank to perform refueling until the real-time oil storage depth of the tank is greater than or equal to the normal oil storage depth of the tank.

2. The method according to claim 1, wherein, The control of the pressure relief valve of the corresponding tank to relieve pressure comprises: Step S21, receiving a pressure relief instruction for pressure relief; Step S22, judging a pressure relief state of the pressure relief valve, wherein the pressure relief state comprises a pressure relief state and a non-pressure relief state; When the pressure relief valve is in the non-pressure relief state, according to the pressure relief instruction, judging whether the pressure relief oil temperature is greater than or equal to a pressure relief temperature threshold value, if yes, controlling the pressure relief valve to open to relieve pressure; When the pressure relief valve is in the pressure relief state, according to the pressure relief instruction, judging whether the pressure relief oil temperature is less than the pressure relief temperature threshold value, if yes, controlling the pressure relief valve to open to relieve pressure; Step S23, repeating step S22, and when the pressure relief valve is in the pressure relief state, collecting the pressure relief oil temperature of oil at different time periods at different times, and judging the stability of the real-time pressure relief state based on the dispersion according to the liquid outlet rate of the pressure relief valve. The judgment of the stability of the real-time pressure relief state based on the dispersion comprises:

3. The method according to claim 2, wherein, Step S231, extracting the pressure relief oil temperature at different times; Step S232, judging whether the difference between the maximum value and the minimum value of the pressure relief oil temperature meets a predetermined threshold value, if the difference between the maximum value and the minimum value of the pressure relief oil temperature is less than or equal to the preset dispersion predetermined threshold value, step S234 is entered; Step S233, if the difference between the maximum value and the minimum value of the pressure relief oil temperature is greater than the preset dispersion predetermined threshold value, judging whether the time difference between the time corresponding to the minimum value of the pressure relief oil temperature and the time corresponding to the maximum value of the pressure relief oil temperature meets a preset time difference threshold value, if the time difference is less than or equal to the preset time difference threshold value, controlling the pressure relief valve to stop relieving pressure, if the time difference is greater than the preset time difference threshold value, controlling the pressure relief valve to continue relieving pressure; Step S234, when the pressure relief valve maintains pressure relief for a time greater than or equal to the time difference threshold value, judging whether the pressure relief oil temperature meets a condition, if the pressure relief oil temperature is greater than or equal to a pressure relief temperature threshold value, controlling the pressure relief valve to continue relieving pressure, if the pressure relief oil temperature is less than the pressure relief temperature threshold value, controlling the pressure relief valve to stop relieving pressure. ​ ​ 4. The method of claim 1, wherein, The control of the pressure reducing valve of the corresponding tank includes: Step S41, receiving a pressure compensation instruction for pressure compensation; Step S42, judging the pressure compensation state of the pressure reducing valve, the pressure compensation state including a pressure compensation state and a non-pressure compensation state; When the pressure reducing valve is in the non-pressure compensation state, according to the pressure compensation instruction, judging whether the oil temperature is greater than the pressure compensation temperature threshold, if yes, controlling the pressure reducing valve to open to perform pressure compensation; When the pressure reducing valve is in the pressure compensation state, according to the pressure compensation instruction, judging whether the pressure compensation oil temperature is less than the pressure compensation temperature threshold, if yes, controlling the pressure reducing valve to open to perform pressure compensation; Step S43, repeating step S42, and when the pressure reducing valve is in the pressure compensation state, collecting the pressure compensation oil temperature of the oil liquid at different time periods, and judging the stability of the real-time pressure compensation state based on the dispersion degree according to the liquid inlet rate of the pressure reducing valve. The judgment of the stability of the real-time pressure compensation state based on the dispersion degree includes:

5. The method according to claim 4, wherein, Step S431, extracting the pressure compensation oil temperature at different times; Step S432, judging whether the difference between the maximum value and the minimum value of the pressure compensation oil temperature meets the condition: if the difference between the maximum value and the minimum value of the pressure compensation oil temperature is less than or equal to the preset dispersion degree threshold, step S434 is entered; Step S433, if the difference between the maximum value and the minimum value of the pressure compensation oil temperature is greater than the preset dispersion degree threshold, judging whether the time difference between the time corresponding to the minimum value of the pressure compensation oil temperature and the time corresponding to the maximum value of the pressure compensation oil temperature meets the condition: if the time difference is less than or equal to the preset time difference threshold, controlling the pressure reducing valve to stop pressure compensation; if the time difference is greater than the preset time difference threshold, controlling the pressure reducing valve to continue pressure compensation; Step S434, when the pressure reducing valve keeps pressure compensation for a time greater than or equal to the time difference threshold, judging whether the pressure compensation oil temperature meets the condition: if the pressure compensation oil temperature is less than the pressure compensation temperature threshold, controlling the pressure reducing valve to continue pressure compensation; if the pressure compensation oil temperature is greater than the pressure compensation temperature threshold, controlling the pressure reducing valve to stop pressure compensation. Further comprising steps: Step S61, when the pressure reducing valve is in the pressure relief state, judging the real-time pressure relief state based on the state of the oil liquid at the oil outlet, the state of the oil liquid at the oil outlet including oil liquid flowing out or no oil liquid flowing out; 6. The method of claim 1, wherein the step of determining the state of the grain oil production process comprises determining the state of the grain oil production process based on the at least one of the plurality of process parameters. Step S62, if the state of the oil liquid at the oil outlet is oil liquid flowing out, controlling the pressure reducing valve to continue pressure relief, and repeating step S61; Step S63, if the state of the oil liquid at the oil outlet is no oil liquid flowing out, judging the real-time pressure relief state of the pressure reducing valve based on the pressure relief rate and the real-time pressure relief pressure. The judgment of the real-time pressure relief state of the pressure reducing valve based on the pressure relief rate and the real-time pressure relief pressure includes: Step S631, calculating the pressure relief rate of the real-time pressure relief pressure; 7. The method according to claim 6, wherein, Step S632, obtaining the pressure relief rate corresponding to the real-time pressure relief pressure; Step S633, calculating the change rate of the pressure relief rate, obtaining the maximum change rate and the time corresponding to the maximum change rate; Step S634, obtaining the pressure relief rate at the end of the real-time pressure relief; ​ ​ Step S635, judging the pressure relief stable state according to the preset change rate threshold and time difference threshold: When the change rate is less than the change rate threshold, determining the pressure relief stable state; When the change rate is greater than or equal to the change rate threshold, calculating the time difference between the time corresponding to the maximum change rate and the time when the change rate corresponding to the real-time pressure relief rate reaches the change rate threshold in step S634; If the time difference is less than or equal to the time difference threshold, determining the pressure relief stable state; if the time difference is greater than the time difference threshold, controlling the pressure relief valve to continue pressure relief.

8. The method according to claim 6, wherein, The state of the oil outlet end oil includes: Step S81, setting an optical sensor between the oil outlet end and the storage tank, the optical sensor judging the oil state based on a preset distance threshold; Step S82, if the oil flow rate of the oil outlet end is less than the preset oil flow rate threshold, the optical sensor does not sense oil, then determining that the state of the oil outlet end oil is no oil flowing out; Step S83, if the oil flow rate of the oil outlet end is greater than or equal to the preset oil flow rate threshold, the optical sensor senses oil, then determining that the state of the oil outlet end oil is oil flowing out.

9. The method of claim 1, wherein the step of determining the state of the grain oil production process comprises determining the state of the grain oil production process based on the at least one of the plurality of process parameters. Further comprising steps: Step S91, judging whether the real-time oil storage depth of the storage tank meets the predetermined storage depth based on the real-time oil storage depth of the storage tank; Step S92, when the real-time oil storage depth of the storage tank is greater than the predetermined storage depth of the oil in the storage tank, controlling the oil outlet end of the storage tank to discharge oil at a constant flow rate; Step S93, when the real-time oil storage depth of the storage tank is less than the predetermined storage depth of the oil in the storage tank, controlling the storage tank to enter oil replenishment.

10. The method of claim 1, wherein the step of determining the state of the grain oil production process comprises determining the state of the grain oil production process based on the at least one of the plurality of process parameters. Further comprising steps: Step S101, setting an electric field instrument connected with the corresponding storage tank for detecting real-time data of the electric field instrument; Step S102, presetting upper and lower thresholds of the data detected by the electric field instrument; Step S103, when the real-time data of the electric field instrument does not reach the stable range of the real-time data, collecting the change rate of the real-time data, and using the change rate to judge whether the specific volume of the oil is inaccurate; Step S104, if the change rate is less than or equal to the preset change rate threshold, determining that the specific volume of the oil is inaccurate; if the change rate is greater than the preset change rate threshold, determining that the specific volume of the oil is accurate; Step S105, comparing the upper and lower thresholds of the real-time data with the specific volume data of the oil to obtain the stable range of the real-time data: when the real-time data is greater than or equal to the specific volume data, determining that the real-time data is in the inaccurate range; when the real-time data is less than or equal to the specific volume data, determining that the specific volume data is in the inaccurate range. ​

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