Baijiu storage tank top pressure analysis method and intelligent pressure control system

Abstract

The invention provides a white spirit storage tank top pressure analysis method, which comprises the following steps of: detecting top temperature, top pressure and liquid level in real time, establishing a prediction model of the top temperature and the top pressure based on a dimensional analysis method, and correcting the prediction model by adopting multiple linear regression to obtain a relationship between the top temperature and the time and between the top pressure and the time; according to the relation, the top pressure of the storage tank is analyzed, the problem that the top pressure of the storage tank cannot be analyzed in the prior art is solved, the intelligent pressure control system of the white spirit storage tank is further provided, the top pressure is calculated according to the relation, the white spirit storage tank is automatically cooled through the spraying device, it is guaranteed that the top pressure of the storage tank is within a proper range, and therefore safety guarantee is provided. The method is suitable for top pressure analysis and intelligent pressure control of the white spirit storage tank.

Description

Technical Field

[0001] The invention relates to the technical field of liquor storage, and in particular to a liquor storage tank top pressure analysis method and an intelligent pressure control system. Background Art

[0002] The liquor storage tank relies on the opening and closing pressure values ​​set by the breathing valve on the tank top. It automatically opens or closes when the positive and negative pressures in the tank exceed the limit, maintaining the pressure balance inside and outside the tank, thereby ensuring the safe operation of the storage tank. At the same time, the normal opening and closing of the breathing valve can prevent excessive volatilization and loss of liquor.

[0003] The selection of the breathing valve on the top of the liquor storage tank (i.e. the negative and positive pressure limit range of the breathing valve) depends on the saturated vapor pressure of the liquor at different temperatures. There is currently no research data on the saturated vapor pressure of edible liquor. In addition, it is impossible to accurately select the breathing valve when designing the tank. If the opening pressure of the breathing valve is set too high, the design strength requirements of the tank will be increased, thereby increasing the manufacturing cost of the tank. If the opening pressure of the breathing valve is set too low, the volatilization pressure of the liquor in the tank will easily cause the breathing valve to open frequently, thereby increasing the volatilization loss of the liquor. If the breathing valve has a mechanical failure and cannot open or close normally, it will cause the positive pressure in the tank to be too high or the negative pressure to be too low, endangering the safety of the tank.

[0004] At the same time, as the ambient temperature of open-air liquor storage tanks rises, the pressure inside the tanks will increase, increasing evaporation losses and creating safety risks. Summary of the invention

[0005] The technical problem solved by the present invention is to provide a method for analyzing the top pressure of a liquor storage tank and an intelligent pressure control system, so as to solve the problem that the prior art cannot analyze the top pressure of the storage tank.

[0006] The present invention solves the above technical problems by adopting a technical solution: a method for analyzing the pressure at the top of a liquor storage tank, comprising the following steps:

[0007] S1. Install a temperature sensor, a pressure sensor, a radar level gauge and a breathing valve on the top of the liquor storage tank. The temperature sensor is used to detect the top temperature, the pressure sensor is used to detect the top pressure, the radar level gauge is used to detect the tank liquid level, and the breathing valve is used to ensure the safety of the liquor storage tank.

[0008] S2, connect the temperature sensor, pressure sensor and radar level gauge to the PLC control system;

[0009] S3, real-time detection of top temperature, top pressure and tank liquid level, and based on dimensional analysis, a prediction model of top temperature and top pressure is established, and multiple linear regression is used to correct the prediction model to obtain the relationship between top temperature and top pressure and time;

[0010] S4. Analyze the top pressure of the storage tank based on the relationship.

[0011] Furthermore, the relationship between the top temperature and the top pressure and time is: Wherein P represents the top pressure, t1 represents the first time point, T1 represents the top temperature corresponding to t1, P1 represents the top pressure corresponding to t1, t2 represents the second time point, T2 represents the top temperature corresponding to t2, t represents the time required for the top pressure to change from P1 to P, and K1 and K2 are the corrected coefficients.

[0012] Furthermore, analyzing the top pressure of the storage tank based on the relationship includes: calculating the top pressure corresponding to a set time point, and calculating the time required for the top pressure to reach a preset value, the set time point is greater than t2, the preset value of the top pressure is not greater than the maximum saturated vapor pressure, and the starting point of the required time is t1.

[0013] Furthermore, the top pressure analysis method of liquor storage tanks also includes: using the maximum detected top pressure as the minimum value for the positive pressure opening of the breathing valve, and using the minimum detected top pressure as the minimum value for the negative pressure opening of the breathing valve, for the selection of breathing valves and the design of tank strength. The intelligent pressure control system for liquor storage tanks includes a temperature sensor, a pressure sensor, a radar level gauge, a PLC control system, and a spray device. The temperature sensor, the pressure sensor, the radar level gauge, and the spray device are respectively connected to the PLC control system. The PLC control system is provided with a program for automatically controlling the spray device. The program for automatically controlling the spray device includes: when the temperature rises, the time required for the top pressure to reach the first set value is calculated based on the relationship obtained in the top pressure analysis method of liquor storage tanks, and the spray device is opened to cool the tank before the top pressure reaches the first set value.

[0014] Furthermore, the program for automatically controlling the spray device also includes: when the temperature drops, calculating the time required for the top pressure to reach a second set value based on the relationship obtained in the white wine storage tank top pressure analysis method, and closing the spray device when the top pressure reaches the second set value.

[0015] Furthermore, the PLC control system is also provided with an early warning program, which includes: when the pressure detected by the pressure sensor is greater than a high pressure threshold or lower than a low pressure threshold, an alarm is issued.

[0016] Furthermore, the early warning procedure also includes: issuing an early warning when the liquid level in the storage tank exceeds a liquid level over-limit value.

[0017] Beneficial effects of the present invention: The present invention provides a method for analyzing the top pressure of a liquor storage tank, which detects the top temperature, top pressure and liquid level in real time, and based on the dimensional analysis method, establishes a prediction model for the top temperature and top pressure, and uses multiple linear regression to correct the prediction model to obtain the relationship between the top temperature and top pressure and time; the top pressure of the storage tank is analyzed according to the relationship, which solves the problem that the prior art cannot analyze the top pressure of the storage tank, and at the same time, the maximum value of the top pressure detected is used as the minimum value for the positive pressure opening of the breathing valve, and the minimum value of the top pressure detected is used as the minimum value for the negative pressure opening of the breathing valve, which is used for the selection of the breathing valve and the strength design of the storage tank, thereby saving costs; an intelligent pressure control system for a liquor storage tank is also provided, which calculates the top pressure according to the relationship, and automatically cools the liquor storage tank through a spray device to ensure that the top pressure of the storage tank is within an appropriate range, thereby providing safety protection; an early warning program is also provided to determine whether the breathing valve is normal. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic flow chart of the white wine storage tank top pressure analysis method provided by the present invention. DETAILED DESCRIPTION

[0019] The present invention provides a method for analyzing the top pressure of a liquor storage tank, such as Figure 1 As shown, the following steps are included:

[0020] S1. Install a temperature sensor, a pressure sensor, a radar level gauge and a breathing valve on the top of the liquor storage tank. The temperature sensor is used to detect the top temperature, the pressure sensor is used to detect the top pressure, the radar level gauge is used to detect the tank liquid level, and the breathing valve is used to ensure the safety of the liquor storage tank.

[0021] S2, connect the temperature sensor, pressure sensor and radar level gauge to the PLC control system;

[0022] S3, real-time detection of top temperature, top pressure and tank liquid level, and based on dimensional analysis, a prediction model of top temperature and top pressure is established, and multiple linear regression is used to correct the prediction model to obtain the relationship between top temperature and top pressure and time;

[0023] Specifically, for the same storage tank, after storing liquor, the change in the tank liquid level is very small, and the effect on the gas volume is small. Therefore, the effect of the liquid level change on the top pressure is ignored, and the relationship between the top temperature and the top pressure and time is obtained as follows: Where P represents the top pressure, t1 represents the first time point, T1 represents the top temperature corresponding to t1, P1 represents the top pressure corresponding to t1, t2 represents the second time point, T2 represents the top temperature corresponding to t2, t represents the time required for the top pressure to change from P1 to P, K1×(273.5+T2) represents the pressure change caused by the natural evaporation of liquor, It represents the pressure change caused by temperature change. By selecting two time points t1 and t2 as the basis, the changing trend of the top pressure can be predicted. Usually, time points t1 and t2 are both in the temperature rising stage or the temperature falling stage. K1 and K2 are the corrected coefficients. K1 is about 0.0037, usually 0.0037, and K2 is about 480, usually 480.

[0024] S4. Analyze the top pressure of the storage tank based on the relationship.

[0025] Specifically, analyzing the top pressure of the storage tank according to the relationship includes: calculating the top pressure corresponding to a set time point, and calculating the time required for the top pressure to reach a preset value, the set time point is greater than t2, the preset value of the top pressure is not greater than the maximum saturated vapor pressure, and the starting point of the required time is t1.

[0026] In particular, the maximum detected top pressure is used as the minimum value for the positive pressure opening of the breathing valve, and the minimum detected top pressure is used as the minimum value for the negative pressure opening of the breathing valve, which is used for the selection of the breathing valve and the design of the tank strength. In this way, it is possible to avoid inappropriate opening pressure of the breathing valve, thereby increasing the evaporation loss of the liquor. In addition, the saturated vapor pressure of liquors of different degrees at different temperatures can be obtained through historical measured data, that is, the maximum value of the top pressure of a storage tank storing liquor of a certain degree at a certain temperature is used as the saturated vapor pressure of the liquor of that degree at that temperature. For example, the top of a 60% Vol liquor storage tank The maximum pressure is 1320Pa, and the minimum pressure at the top of the tank is -280Pa. Therefore, when selecting the breathing valve, the pressure range should be appropriately expanded. For example, the pressure range for closing the breathing valve is -295Pa to 1765Pa. When the pressure is not within the range of -295Pa to 1765Pa, the breathing valve opens to connect the inside of the tank to the atmosphere. In this way, under normal circumstances, the top pressure will not exceed this range, thereby avoiding the volatilization of the wine. In addition, the temperature corresponding to the top pressure of 1320Pa is 14°C, that is, the saturated vapor pressure of 60% Vol liquor at 14°C is 1320Pa.

[0027] Based on the above-mentioned relationship between top temperature and top pressure and time, the present invention also provides an intelligent pressure control system for a liquor storage tank, comprising a temperature sensor, a pressure sensor, a radar level gauge, a PLC control system and a spray device, wherein the temperature sensor, the pressure sensor, the radar level gauge and the spray device are respectively connected to the PLC control system, and the PLC control system is provided with a program for automatically controlling the spray device, and the program for automatically controlling the spray device comprises: when the temperature rises, calculating the time required for the top pressure to reach a first set value according to the relationship, and turning on the spray device to cool down the storage tank before the top pressure reaches the first set value; the program for automatically controlling the spray device also comprises: when the temperature drops, calculating the time required for the top pressure to reach a second set value according to the relationship, and turning off the spray device when the top pressure reaches the second set value.

[0028] For example, the first setting value is 1000Pa, and the second setting value is 500Pa. When the temperature rises, the time required for the top pressure to reach the first setting value is calculated based on the relationship, and the spray device is turned on to cool the tank before the top pressure reaches the first setting value. After the spray device is turned on, the tank temperature decreases and the top pressure decreases. When the temperature drops, the time required for the top pressure to reach the second setting value is calculated based on the relationship, and the spray device is turned off when the top pressure reaches the second setting value, so as to ensure that the top pressure is between 500Pa and 1000Pa.

[0029] Furthermore, the PLC control system is also provided with an early warning program, which includes: when the pressure detected by the pressure sensor is greater than the high pressure threshold or lower than the low pressure threshold, an alarm is issued. Under normal circumstances, the high pressure threshold is 1900Pa, slightly higher than 1765Pa, and the low pressure threshold is -300Pa, slightly lower than -295Pa. Therefore, if the pressure detected by the pressure sensor is higher than 1900Pa or lower than -300Pa, it means that the breathing valve fails to open, and there is a safety hazard. An alarm is issued to prompt the corresponding staff, who can use this to determine whether the breathing valve is normal. The early warning program also includes: when adding liquor to the storage tank, when the tank liquid level exceeds the liquid level limit value, an early warning is issued to prevent overflow due to excessive volume of liquor stored in the tank.

Claims

1. A method for analyzing the top pressure of a liquor storage tank, characterized in that: The following steps are involved: S1. Install a temperature sensor, a pressure sensor, a radar level gauge and a breathing valve on the top of the liquor storage tank. The temperature sensor is used to detect the top temperature, the pressure sensor is used to detect the top pressure, the radar level gauge is used to detect the tank liquid level, and the breathing valve is used to ensure the safety of the liquor storage tank. S2, connect the temperature sensor, pressure sensor and radar level gauge to the PLC control system; S3, real-time detection of top temperature, top pressure and tank liquid level, and based on dimensional analysis, a prediction model of top temperature and top pressure is established, and multiple linear regression is used to correct the prediction model to obtain the relationship between top temperature and top pressure and time; S4. Analyze the top pressure of the storage tank based on the relationship.

2. The method for analyzing the top pressure of a liquor storage tank according to claim 1, characterized in that: The relationship between the top temperature and the top pressure and time is: Wherein P represents the top pressure, t1 represents the first time point, T1 represents the top temperature corresponding to t1, P1 represents the top pressure corresponding to t1, t2 represents the second time point, T2 represents the top temperature corresponding to t2, t represents the time required for the top pressure to change from P1 to P, and K1 and K2 are the corrected coefficients.

3. The method for analyzing the top pressure of a liquor storage tank according to claim 2, characterized in that: Analyzing the top pressure of the storage tank according to the relationship includes: calculating the top pressure corresponding to a set time point, and calculating the time required for the top pressure to reach a preset value, the set time point is greater than t2, the preset value of the top pressure is not greater than the maximum saturated vapor pressure, and the starting point of the required time is t1.

4. The method for analyzing the top pressure of a liquor storage tank according to claim 1, characterized in that: Also includes: The maximum detected top pressure is used as the minimum value for the positive pressure opening of the breathing valve, and the minimum detected top pressure is used as the minimum value for the negative pressure opening of the breathing valve, which are used for the selection of breathing valves and the strength design of storage tanks.

5. Intelligent pressure control system for liquor storage tanks, characterized in that: It includes a temperature sensor, a pressure sensor, a radar level gauge, a PLC control system and a spray device, wherein the temperature sensor, the pressure sensor, the radar level gauge and the spray device are respectively connected to the PLC control system, and the PLC control system is provided with a program for automatically controlling the spray device, and the program for automatically controlling the spray device includes: when the temperature rises, calculating the time required for the top pressure to reach a first set value according to the relationship obtained in the white wine storage tank top pressure analysis method as claimed in claim 1, and turning on the spray device to cool down the storage tank before the top pressure reaches the first set value.

6. The intelligent pressure control system for liquor storage tanks according to claim 5 is characterized in that: The program for automatically controlling the spray device also includes: when the temperature drops, calculating the time required for the top pressure to reach a second set value based on the relationship obtained in the white wine storage tank top pressure analysis method as described in claim 1, and closing the spray device when the top pressure reaches the second set value.

7. The intelligent pressure control system for liquor storage tanks according to claim 5 or 6, characterized in that: The PLC control system is also provided with an early warning program, which includes: when the pressure detected by the pressure sensor is greater than a high pressure threshold or lower than a low pressure threshold, an alarm is issued.

8. The intelligent pressure control system for liquor storage tanks according to claim 7 is characterized in that: The early warning procedure also includes: when the liquid level in the storage tank exceeds the liquid level over-limit value, issuing an early warning.

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