Full-automatic separation control method for balance of rectifying tower system

Abstract

The invention relates to the technical field of rectification, in particular to a balanced full-automatic separation control method for a rectifying tower system, the rectifying tower system comprises a rectifying tower I. The control method comprises the following steps: carrying out material balance control and gas-liquid balance control on the rectifying tower I. The gas-liquid balance control is used for controlling the reflux quantity of a material refluxed into the rectifying tower I; the material balance control comprises the following steps: detecting the actual feeding flow of the rectification tower I and the actual liquid level value of a first reflux tank corresponding to the rectification tower I, and calculating and controlling the flow of the material extracted from the tower top of the rectification tower I in real time by combining the set value of the component extracted from the tower top of the rectification tower I and the density of the component extracted from the tower top. Through the preparation method, the stability and the efficiency of a rectifying tower system are improved, and the energy consumption cost and the product volatility problem are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of distillation, and in particular to a fully automated separation control method for a distillation tower system balance. Background Art

[0002] At present, the automation control of distillation towers mainly utilizes a certain temperature, pressure, and liquid level measurement point on the distillation tower and its ancillary equipment to associate the flow and regulating valve for automatic control (divided into cascade control and automatic control). For example, the bottom liquid level is associated with the reflux regulating valve or the reflux volume for adjustment control, and the feed flow and feed regulating valve are automatically controlled.

[0003] The above technical scheme is relatively simple and the system adjustment efficiency is low. It cannot be fully automatic and requires personnel to make continuous adjustments. For example, after the feed flow rate is adjusted, the personnel need to adjust the distillation tower bottom extraction, tower top extraction, steam consumption, reflux volume, etc. Although the use of partial flow automation and liquid level automation can appropriately reduce personnel operations, the adjustment efficiency is too low and the structure is simple, which cannot quickly meet the needs of system adjustment. In essence, after the previous parameter adjustment, it is necessary to wait for the subsequent measurement point to deviate from the set value (the actual value deviates from the set value) before making the next adjustment. For example, after increasing the feed rate, it is necessary to wait until the liquid level in the reflux tank rises and deviates from the set value before adjusting the top extraction flow. At the same time, due to the change in feed rate, but the extraction volume has not changed in time, the material inside the system is accumulated, the steam energy consumption will increase, and the impurity separation effect of the system will be reduced, affecting the overall system energy consumption and separation effect. Summary of the invention

[0004] In order to solve the above technical problems, the present invention proposes a fully automated separation control method for a balanced distillation tower system, which improves the stability and efficiency of the distillation tower system, saves manual operation costs, avoids personnel misoperation, reduces energy consumption costs and product volatility, improves the separation effect of the distillation tower, and improves product quality.

[0005] The present invention is achieved by adopting the following technical solutions: A fully automated separation control method for a distillation tower system balance, the distillation tower system includes a distillation tower I, the control method includes material balance control and gas-liquid balance control on the distillation tower I, the gas-liquid balance control is used to control the reflux amount of materials refluxed into the distillation tower I; the material balance control includes: detecting the actual feed flow of the distillation tower I and the actual liquid level value of the first reflux tank corresponding to the distillation tower I, combining the tower top extraction component set value and the tower top extraction component density of the distillation tower I, and calculating and controlling the tower top extraction material flow of the distillation tower I in real time; wherein, the calculation method of the tower top extraction material flow of the distillation tower I is: The top extraction material flow rate of distillation tower I = actual feed flow rate * top extraction component set value / top extraction component density + first correction value; first correction value = (actual liquid level value of the first reflux tank - set liquid level value of the first reflux tank) / liquid level deviation set value of the first reflux tank * set correction value.

[0006] The material balance control also includes: controlling the bottom extraction amount of the distillation tower I according to the actual bottom liquid level of the distillation tower I.

[0007] The gas-liquid balance control specifically refers to: controlling the reflux amount of materials flowing back into the distillation tower I according to the actual temperature of the distillation section of the distillation tower I or the actual bottom liquid level of the distillation tower I.

[0008] The gas-liquid balance control specifically refers to: setting the reflux ratio coefficient value, the reflux ratio refers to the ratio of the reflux flow rate to the material flow rate of the tower top; calculating the reflux output value by calculating the material flow rate of the tower top; calculating the deviation between the actual temperature and the preset temperature or the deviation between the actual tower bottom liquid level and the preset tower bottom liquid level according to the actual temperature of the distillation section of the distillation tower I or the actual tower bottom liquid level of the distillation tower I; calculating and controlling the reflux amount of the material refluxed to the distillation tower I: Reflux flow rate = reflux flow rate output value + second correction value; second correction value = (actual temperature - preset temperature) / temperature deviation setting * setting correction value; or, reflux flow rate = reflux flow rate output value + third correction value; third correction value = (actual tower bottom liquid level - preset tower bottom liquid level) / tower bottom liquid level deviation setting value * setting correction value.

[0009] When it is a multi-component impurity separation distillation tower, the gas-liquid balance is controlled according to the actual temperature of the distillation section of the distillation tower; when it is a single-component impurity separation distillation tower, the gas-liquid balance is controlled according to the actual bottom liquid level of the distillation tower.

[0010] It also includes energy balance control of the distillation tower I, and the energy balance control specifically refers to: controlling the circulating water volume according to the outlet temperature of the material after cooling by the first cooler corresponding to the distillation tower I; and controlling the steam volume according to the gas phase temperature of the material near the reboiler in the tower bottom.

[0011] Controlling the steam volume according to the gas phase temperature of the material in the first reboiler at the bottom of the tower specifically includes: Steam volume = set basic steam flow + fourth correction value; fourth correction value = (actual material gas phase temperature of the bottom of the tower near the first reboiler - preset material gas phase temperature of the bottom of the tower near the first reboiler) / gas phase temperature deviation set value * set correction value.

[0012] The distillation system also includes a distillation tower II connected in series with the distillation tower I, and the control method also includes top extraction control and reflux control of the distillation tower II; the top extraction control specifically refers to: controlling the top extraction amount according to the top temperature of the distillation tower II, and the reflux control specifically refers to: controlling the reflux amount according to the liquid level of the second reflux tank corresponding to the distillation tower II.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. In the present invention, through material balance control and gas-liquid balance control, the distillation tower system can be fully automatically controlled from the input and output of materials and the separation effect, and the accuracy and timeliness of the control can be improved. Accuracy means that the present invention can be adjusted according to the liquid level or temperature deviation, and the corresponding calculation and output control value can be performed regardless of the size. Timeliness means that the present invention can calculate in real time. The difference from the traditional PID control is that the traditional control requires the actual value to reach the set value before it starts to adjust, and it will not be reduced in advance. For example, when the temperature is controlled at 50°C and the steam flow rate is 10t / h, when the temperature is as low as 49°C, the traditional PID control starts to increase the steam flow rate and will continue to increase until the temperature returns to 50°C before adjusting to reduce the steam flow rate. The temperature will be higher than 50°C and cannot be quickly restored; the control method of the present invention calculates the output value based on the real-time deviation, and increases or decreases synchronously, and there will be no hysteresis periodic sinusoidal fluctuation curve.

[0014] Furthermore, when performing material balance control, by analyzing the separation of different volatility components of the material by the distillation tower, the feed components and the actual top extraction components can be obtained through detection means. Since the material components in industrial production are not necessarily constant and have certain volatility, the present invention innovatively introduces a first correction value to solve the volatility problem in actual industrial production and improve the stability and efficiency of the system.

[0015] 2. In the present invention, when performing gas-liquid equilibrium control, different parameters can be selected for corresponding control according to the type of component separation, and the control accuracy and stability are better.

[0016] 3. The present invention also includes energy balance control, which can automatically control energy consumption, and combines material balance control and gas-liquid balance control to make the control method more comprehensive.

[0017] 4. In the present invention, the series-connected distillation tower I and distillation tower II adopt high-low pressure coupling, which reduces energy consumption and improves energy utilization efficiency. Based on this, the heat source of distillation tower II depends on distillation tower I. As the steam consumption of distillation tower I changes, the change of the tower bottom liquid level will be affected. The rising steam volume and the refluxed liquid volume in the tower need to be controlled, that is, the reflux is associated with the tower bottom liquid level to ensure the response to heat changes. In view of the above characteristics, the reflux volume is controlled according to the liquid level of the reflux tank of distillation tower II, and a different control method from distillation tower I is adopted, so that the gas-liquid balance effect of distillation tower II is better.

[0018] Since the distillation tower II needs to separate unnecessary components from the top of the tower during the production process, the quantity and composition need to be controlled, that is, the material composition at a certain temperature at the top of the tower is obtained through calculation and simulation to meet the production needs (the top of the tower cannot over-extract the materials we need, nor can it under-extract unnecessary materials). In order to cope with the actual changes in the amount of material that needs to be separated from the front-end incoming materials in production (it may be more or less at times), the top extraction amount of the distillation tower II is controlled according to the top extraction temperature to achieve automatic adjustment of the top extraction amount of the distillation tower II. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, wherein: Figure 1 It is a structural schematic diagram of the distillation tower system in the present invention; Markings in the figure: 1. Distillation tower I, 2. Distillation tower II, 3. First temperature detector, 4. Second temperature detector, 5. Third temperature detector, 6. Fourth temperature detector, 7. Fifth temperature detector, 8. First liquid level detector, 9. Second liquid level detector, 10. Third liquid level detector, 11. Fourth liquid level detector, 12. First regulating valve, 13. Second regulating valve, 14. Third regulating valve, 15. Fourth regulating valve, 16. Fifth regulating valve, 17. Sixth regulating valve, 18. Seventh regulating valve Throttle valve, 19, eighth regulating valve, 20, fourth detection meter, 21, first reflux tank, 22, first reboiler, 23, second reboiler, 24, first cooler, 25, second cooler, 26, first reflux pump, 27, second reflux pump, 28, first detection meter, 29, second detection meter, 30, third detection meter, 31, tenth regulating valve, 32, eleventh regulating valve, 33, second reflux tank, 34, third cooler, 35, fourth flow meter, 36, fifth detection meter. DETAILED DESCRIPTION

[0020] Example 1 As a basic embodiment of the present invention, the present invention includes a fully automated separation control method for the balance of a distillation tower system. The distillation tower system includes a distillation tower 1 I, and the control method includes material balance control and gas-liquid balance control of the distillation tower 1 I. Among them, the gas-liquid balance control is used to control the reflux amount of materials refluxed into the distillation tower 1 I. The material balance control includes: detecting the actual feed flow of the distillation tower I 1 and the actual liquid level value of the first reflux tank 21 corresponding to the distillation tower I 1, combining the top extraction component set value of the distillation tower I 1 and the density of the top extraction component, and calculating and controlling the top extraction material flow of the distillation tower I 1 in real time. Specifically, the calculation method of the top extraction material flow of the distillation tower I 1 is: The top extraction material flow rate of distillation tower 1 = actual feed flow rate * top extraction component set value / top extraction component density + first correction value. Among them, the first correction value = (actual liquid level value of the first reflux tank 21 - set liquid level value of the first reflux tank 21) / liquid level deviation set value of the first reflux tank 21 * set correction value. Among them, the set liquid level value of the first reflux tank 21, the liquid level deviation set value of the first reflux tank 21 and the set correction value can be obtained according to simulation calculation, or by analyzing historical operation data.

[0021] Example 2 As a preferred embodiment of the present invention, the present invention includes a fully automated separation control method for a distillation tower system balance. The distillation tower system includes a distillation tower 1, and the control method includes material balance control and gas-liquid balance control of the distillation tower 1. The gas-liquid balance control is used to control the reflux amount of the material refluxed into the distillation tower 1. Specifically, the reflux amount of the material refluxed into the distillation tower 1 can be controlled according to the actual temperature of the distillation section of the distillation tower 1 or the actual bottom liquid level of the distillation tower 1.

[0022] The material balance control includes controlling the top material flow rate of distillation tower 1 and controlling the bottom material flow rate of distillation tower 1. Among them, the bottom material flow rate of distillation tower 1 can be controlled according to the actual bottom liquid level of distillation tower 1. The control of the top material flow rate of distillation tower 1 specifically includes: detecting the actual feed flow rate of distillation tower 1 and the actual liquid level value of the first reflux tank 21 corresponding to distillation tower 1, combining the top material flow rate of distillation tower 1 set value and the top material flow rate density of distillation tower 1, and calculating and controlling the top material flow rate of distillation tower 1 in real time. Specifically, the calculation method of the top material flow rate of distillation tower 1 is: The top extraction material flow rate of distillation tower 1 = actual feed flow rate * top extraction component set value / top extraction component density + first correction value. Among them, the first correction value = (actual liquid level value of the first reflux tank 21 - set liquid level value of the first reflux tank 21) / liquid level deviation set value of the first reflux tank 21 * set correction value.

[0023] Example 3 As another preferred embodiment of the present invention, the present invention includes a fully automated separation control method for the balance of a distillation tower system. The distillation tower system includes a distillation tower 1, and the control method includes material balance control, gas-liquid balance control, and energy balance control of the distillation tower 1. Among them, the gas-liquid balance control is used to control the reflux amount of the material refluxed into the distillation tower 1. The energy balance control specifically refers to: controlling the circulating water volume according to the outlet temperature of the material after cooling by the first cooler 24 corresponding to the distillation tower 1; and controlling the steam volume according to the gas phase temperature of the material near the first reboiler 22 in the tower bottom.

[0024] The material balance control includes: detecting the actual feed flow rate of the distillation tower 1 and the actual liquid level value of the first reflux tank 21 corresponding to the distillation tower 1, and combining the set value of the top extraction component of the distillation tower 1 and the density of the top extraction component, and calculating and controlling the top extraction material flow rate of the distillation tower 1 in real time. Specifically, the calculation method of the top extraction material flow rate of the distillation tower 1 is: The top extraction material flow rate of distillation tower 1 = actual feed flow rate * top extraction component set value / top extraction component density + first correction value. Among them, the first correction value = (actual liquid level value of the first reflux tank 21 - set liquid level value of the first reflux tank 21) / liquid level deviation set value of the first reflux tank 21 * set correction value.

[0025] Through the above control method, comprehensive automatic control of the distillation system of a single distillation tower can be achieved in terms of input and output materials, energy consumption and separation effect.

[0026] Example 4 As the best embodiment of the present invention, the present invention includes a fully automated separation control method for a distillation tower system balance, wherein, with reference to the attached specification, Figure 1 The distillation tower system includes a distillation tower I 1 and a distillation tower II 2 arranged in series, and also includes a first reflux tank 21 and a first reboiler 22 corresponding to the distillation tower I 1, and includes a second reflux tank 33 and a second reboiler 23 corresponding to the distillation tower II 2.

[0027] The feed pipeline of the distillation tower I 1 is also provided with a first regulating valve 12 and a first detector 28, and the first detector 28 is used to detect the actual feed flow rate. The tower bottom extraction pipeline of the distillation tower I 1 is also provided with a second regulating valve 13 and a third cooler 34. The tower bottom of the distillation tower I 1 is also provided with a second liquid level detector 9, which is used to detect the actual tower bottom liquid level of the distillation tower I 1. The tower bottom of the distillation tower I 1 is provided with a first temperature detector 3 near the first reboiler 22, which is used to detect the actual material gas phase temperature of the tower bottom near the first reboiler 22. The upper half of the distillation tower I 1 is also provided with a second temperature detector 4, which is used to detect the actual temperature of the distillation section (upper half) of the distillation tower I 1. The first reboiler 22 of the distillation tower I 1 is connected to a steam pipeline, and the other end of the steam pipeline is connected to a steam source. The steam pipeline is also provided with a fourth regulating valve 15 and a fourth flowmeter 35.

[0028] The top outlet of the distillation tower 1 is connected to a first pipeline, on which a first cooler 24, a fifth temperature detector 7, a first reflux tank 21 and a first reflux pump 26 are sequentially arranged, and the output end of the first pipeline is connected to two branch pipelines. One of the branch pipelines is provided with a sixth regulating valve 17 and a second detector 29, which are connected to the feed port of the distillation tower 2; the other branch pipeline is provided with a third regulating valve 14 and a third detector 30, which are connected to the upper part of the distillation tower 1. Among them, the material at the top outlet of the distillation tower 1 needs to be heat exchanged with the second reboiler 23 before entering the first cooler 24 through the first pipeline. The first reflux tank 21 is also provided with a first liquid level detector 8.

[0029] The upper half of the distillation tower II 2 is also provided with a third temperature detector 5 for detecting the actual temperature of the distillation section (upper half) of the distillation tower II 2. The bottom of the distillation tower II 2 is also provided with a fourth liquid level detector 11 for detecting the actual bottom liquid level of the distillation tower II 2. The bottom extraction pipeline of the distillation tower II 2 is also provided with a seventh regulating valve 18.

[0030] The top outlet of the distillation tower II 2 is connected to a second pipeline, on which a second cooler 25, a fourth temperature detector 6, a second reflux tank 33 and a second reflux pump 27 are arranged in sequence, and the output end of the second pipeline is connected to two branch pipelines. One of the branch pipelines is provided with an eighth regulating valve 19 and a fourth detector 20; the other branch pipeline is provided with a fifth regulating valve 16 and a fifth detector 36, which are connected to the upper part of the distillation tower II 2. The second reflux tank 33 is also provided with a third liquid level detector 10.

[0031] The first cooler 24 is connected to the circulating water through a first circulating water pipe, on which a tenth regulating valve 31 is also provided. The second cooler 25 is connected to the circulating water through a second circulating water pipe, on which an eleventh regulating valve 32 is also provided.

[0032] Based on the above-mentioned distillation tower system, the present invention provides a fully automated separation control method for the balance of a distillation tower system, including material balance control, gas-liquid balance control and energy balance control of distillation tower I 1, and top extraction control, reflux control, bottom extraction control and circulating water volume control of distillation tower II 2.

[0033] Among them, the material balance control of the distillation tower 1 includes the control of the top material produced of the distillation tower 1 and the control of the bottom production of the distillation tower 1. Specifically, the control of the top material produced of the distillation tower 1 specifically refers to: detecting the actual feed flow of the distillation tower 1 according to the first detector 28, detecting the actual liquid level value of the first reflux tank 21 according to the first liquid level detector 8; combining the top produced component set value of the distillation tower 1 and the top produced component density, calculating the top produced material flow of the distillation tower 1 in real time, and controlling the top produced material flow of the distillation tower 1 through the sixth regulating valve 17. Among them, the calculation method of the top produced material flow of the distillation tower 1 is: The top extraction material flow rate of distillation tower 1 = actual feed flow rate * top extraction component setting value / top extraction component density + first correction value. First correction value = (actual liquid level value of first reflux tank 21 - set liquid level value of first reflux tank 21) / liquid level deviation setting value of first reflux tank 21 * set correction value. Among them, the top extraction component density is actually the density of the top extraction material under controlled temperature and pressure.

[0034] For example, the feed flow rate is 210t / h, the produced component is 33%, the set liquid level value is 50%, the actual liquid level value is 55%, the liquid level deviation set value is 1%, the set correction value is 0.2, and the density value is 1.285.

[0035] Then the output value = 210*0.33 / 1.285+((55%-50%) / 1%*0.2)=54.93 For example, the feed flow rate is 210t / h, the produced component is 33%, the set liquid level value is 50%, the actual liquid level value is 45%, the set deviation value is 1%, the set correction value is 0.2, and the density value is 1.285.

[0036] Then the output value = 210*0.33 / 1.285+((45%-50%) / 1%*0.2)=52.93 The control of the bottom extraction amount of the distillation tower I 1 specifically refers to: according to the actual bottom liquid level of the distillation tower I 1 detected by the second liquid level detector 9, the bottom extraction amount of the distillation tower I 1 is controlled by controlling the second regulating valve 13.

[0037] The gas-liquid balance control of the distillation tower I 1 specifically refers to: according to the actual temperature of the distillation section of the distillation tower I 1 or the actual tower bottom liquid level of the distillation tower I 1, the reflux amount of the material refluxed into the distillation tower I 1 is controlled. Wherein, when the distillation tower I 1 is a multi-component impurity separation distillation tower, the gas-liquid balance is controlled according to the actual temperature of the distillation section of the distillation tower I 1; when the distillation tower I 1 is a single-component impurity separation distillation tower, the gas-liquid balance is controlled according to the actual tower bottom liquid level of the distillation tower I 1, so as to avoid that the gas phase in the distillation tower I 1 enters the first reflux tank 21 through the first cooler 24, resulting in a reduction in the separation effect of components and impurities, and to avoid excessive reflux of reflux materials to the distillation tower I 1, resulting in a reduction in product output and a reduction in steam energy consumption.

[0038] Specifically, the reflux ratio coefficient value is set, and the reflux ratio refers to the ratio of the reflux amount to the material flow rate of the tower top. The reflux amount output value is calculated by the calculated material flow rate of the tower top; the deviation between the actual temperature and the preset temperature or the deviation between the actual tower bottom liquid level and the preset tower bottom liquid level is calculated according to the actual temperature of the distillation section of the distillation tower 1 detected by the second temperature detector 4, or the actual tower bottom liquid level of the distillation tower 1 detected by the second liquid level detector 9; the reflux amount of the material refluxed to the distillation tower 1 is calculated and controlled: Reflux flow rate = reflux flow rate output value + second correction value, second correction value = (actual temperature - preset temperature) / temperature deviation setting * setting correction value.

[0039] The reflux flow output value is to set a reflux flow value through simulation calculation or statistics of previous operating data.

[0040] Or, reflux flow = reflux flow output value + third correction value; third correction value = (actual tower bottom liquid level - preset tower bottom liquid level) / tower bottom liquid level deviation setting * setting correction value.

[0041] The energy balance of the distillation tower 1 is controlled. Specifically, the circulating water volume is controlled according to the outlet temperature of the material after cooling in the first cooler 24 of the distillation tower 1; and the steam volume is controlled according to the gas phase temperature of the material near the first reboiler 22 in the tower bottom.

[0042] Specifically, the outlet temperature of the material after cooling by the first cooler 24 can be detected by the fifth temperature detector 7, and the circulating water volume can be controlled by controlling the tenth regulating valve 31. The steam volume can be controlled by controlling the fourth regulating valve 15 based on the gas phase temperature of the material detected by the first temperature detector 3. The specific calculation method of the steam volume is as follows: Steam volume = set basic steam flow + fourth correction value; fourth correction value = (actual material gas phase temperature of the bottom of the tower near the first reboiler 22 - preset material gas phase temperature of the bottom of the tower near the first reboiler 22) / gas phase temperature deviation setting * set correction value.

[0043] The tower top extraction control of the distillation tower II 2 specifically refers to: according to the actual tower top temperature of the distillation tower II 2 detected by the third temperature detector 5, by comparing it with the preset tower top temperature, by controlling the eighth regulating valve 19, the tower top extraction amount is controlled. Among them, the tower top extraction amount can be calculated by the following method: The top extraction volume of distillation tower 2 of II = the set extraction volume + the fifth correction value; the fifth correction value = (actual tower top temperature - preset tower top temperature) / temperature deviation setting * set correction value.

[0044] The reflux control of the distillation tower II 2 specifically refers to: according to the actual liquid level of the second reflux tank 33 detected by the third liquid level detector 10, by comparing with the preset liquid level, by controlling the fifth regulating valve 16, the reflux amount is controlled. The reflux amount can be calculated in the following way: The reflux rate of distillation tower II 2 = the set reflux rate + the sixth correction value; the sixth correction value = (actual liquid level - preset liquid level) / liquid level deviation setting * set correction value.

[0045] The bottom extraction control of the distillation tower II 2 specifically refers to: controlling the bottom extraction amount of the distillation tower II 2 by controlling the seventh regulating valve 18 according to the actual bottom liquid level of the distillation tower II 2 detected by the fourth liquid level detector 11.

[0046] The tower bottom extraction volume = the set tower bottom extraction volume + the seventh correction value; the seventh correction value = (actual tower bottom liquid level - preset tower bottom liquid level) / liquid level deviation setting * set correction value.

[0047] The circulating water volume control of the distillation tower II 2 specifically means that the outlet temperature of the material after cooling by the second cooler 25 can be detected by the fourth temperature detector 6, and the circulating water volume can be controlled by controlling the eleventh regulating valve 32.

[0048] Through the above control method, comprehensive automated control of the distillation system connected with multiple distillation towers can be achieved in terms of input and output materials, energy consumption and separation effect.

[0049] In summary, after reading the present invention document, ordinary technicians in this field can make various other corresponding transformation schemes based on the technical scheme and technical concept of the present invention without creative mental labor, which all fall within the scope of protection of the present invention.

Claims

1. A fully automated separation control method for a distillation tower system balance, characterized in that: The distillation tower system comprises a distillation tower I (1), and the control method comprises performing material balance control and gas-liquid balance control on the distillation tower I (1), wherein the gas-liquid balance control is used to control the reflux amount of the material refluxed into the distillation tower I (1); The material balance control comprises: detecting the actual feed flow rate of the distillation tower I (1) and the actual liquid level value of the first reflux tank (21) corresponding to the distillation tower I (1), and calculating and controlling the top extraction material flow rate of the distillation tower I (1) in real time in combination with the top extraction component set value and the top extraction component density of the distillation tower I (1); wherein the calculation method of the top extraction material flow rate of the distillation tower I (1) is: The top extraction material flow rate of the distillation tower I (1) = actual feed flow rate * top extraction component set value / top extraction component density + first correction value; first correction value = (actual liquid level value of the first reflux tank (21) - set liquid level value of the first reflux tank (21)) / liquid level deviation set value of the first reflux tank (21) * set correction value.

2. A fully automated separation control method for a distillation tower system balance according to claim 1, characterized in that: The material balance control further comprises: controlling the bottom extraction amount of the distillation tower (1) according to the actual bottom liquid level of the distillation tower (1).

3. A fully automated separation control method for a distillation tower system balance according to claim 1, characterized in that: The gas-liquid balance control specifically refers to: controlling the reflux amount of the material refluxed into the distillation tower I (1) according to the actual temperature of the distillation section of the distillation tower I (1) or the actual bottom liquid level of the distillation tower I (1).

4. A fully automated separation control method for a distillation tower system balance according to claim 3, characterized in that: The gas-liquid balance control specifically refers to: setting the reflux ratio coefficient value, wherein the reflux ratio refers to the ratio of the reflux flow rate to the tower top production material flow rate; calculating the reflux flow output value by using the calculated tower top production material flow rate; Calculating, based on the actual temperature of the distillation section of the distillation tower I (1) or the actual bottom liquid level of the distillation tower I (1), the deviation between the actual temperature and the preset temperature or the deviation between the actual bottom liquid level and the preset bottom liquid level; Calculate and control the reflux rate of materials into the distillation tower I (1): Reflux flow = reflux flow output value + second correction value; The second correction value = (actual temperature - preset temperature) / temperature deviation setting * setting correction value; Or, reflux flow = reflux flow output value + third correction value; third correction value = (actual tower bottom liquid level - preset tower bottom liquid level) / tower bottom liquid level deviation setting value * setting correction value.

5. A fully automated separation control method for a distillation tower system balance according to claim 4, characterized in that: When it is a multi-component impurity separation distillation tower, the gas-liquid balance is controlled according to the actual temperature of the distillation section of the distillation tower; when it is a single-component impurity separation distillation tower, the gas-liquid balance is controlled according to the actual bottom liquid level of the distillation tower.

6. A fully automated separation control method for a distillation tower system balance according to claim 1, characterized in that: The method further includes performing energy balance control on the distillation tower I (1), wherein the energy balance control specifically includes: controlling the amount of circulating water according to the outlet temperature of the material after cooling by the first cooler (24) corresponding to the distillation tower I (1); and controlling the amount of steam according to the gas phase temperature of the material in the tower bottom near the first reboiler (22).

7. A fully automated separation control method for a distillation tower system balance according to claim 6, characterized in that: The method of controlling the steam quantity according to the gas phase temperature of the material in the first reboiler (22) in the bottom of the tower specifically includes: Steam volume = set basic steam flow rate + fourth correction value; fourth correction value = (actual material gas phase temperature of the bottom of the tower near the first reboiler (22) - preset material gas phase temperature of the bottom of the tower near the first reboiler (22)) / gas phase temperature deviation set value * set correction value.

8. A fully automated separation control method for a distillation tower system balance according to any one of claims 1 to 7, characterized in that: The distillation system further comprises a distillation tower II (2) connected in series with the distillation tower I (1), and the control method further comprises performing top extraction control and reflux control on the distillation tower II (2); the top extraction control specifically refers to: controlling the top extraction amount according to the top temperature of the distillation tower II (2), and the reflux control specifically refers to: controlling the reflux amount according to the liquid level of a second reflux tank (33) corresponding to the distillation tower II (2).

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