A low-temperature evaporator vacuum control system and control method thereof

Abstract

The invention discloses a low-temperature evaporator vacuum control system and a control method thereof, which relate to the technical field of low-temperature evaporators and include the following modules: a temperature database building module, for obtaining historical feed wastewater temperatures, obtaining historical temperature differences, establishing a temperature database, and storing the historical feed wastewater temperatures and historical temperature differences in the temperature database; by regulating the heating temperature of the low-temperature evaporator during the temperature adjustment time so that the heating temperature of the low-temperature evaporator is adjusted to the final temperature, thereby predicting the liquid replenishment action, thereby facilitating the low-temperature evaporator to heat up in advance to overcome the phenomenon that the temperature drops during the liquid replenishment process and causes the temperature to be lower than the boiling point temperature; by lowering the heating temperature of the low-temperature evaporator to the current evaporation boiling point temperature of the low-temperature evaporator when the temperature in the low-temperature evaporator rises again, thereby facilitating the evaporation and separation of wastewater at a lower heating temperature, thereby saving more heating energy, being beneficial to environmental protection and reducing cost consumption.

Description

Technical Field

[0001] The invention relates to the technical field of low-temperature evaporators, and in particular to a low-temperature evaporator vacuum control system and a control method thereof. Background Art

[0002] The low-temperature evaporator is a highly efficient evaporation equipment that uses vacuum negative pressure to lower the boiling point of water and evaporates water at a lower temperature. It can effectively treat various wastewaters and solutions. Compared with traditional evaporators, the low-temperature evaporator has many advantages. First, it can operate at a lower temperature, reducing energy consumption and reducing operating costs. Secondly, the low-temperature evaporator has a good protective effect on heat-sensitive substances and avoids high temperature damage to substances. Therefore, the low-temperature evaporator is widely used in chemical, pharmaceutical, food, environmental protection and other fields.

[0003] There are two ways of evaporating wastewater in and out of the low-temperature evaporator: intermittent evaporation and continuous evaporation. Intermittent evaporation means that after the wastewater enters the low-temperature evaporator, the low-temperature evaporator starts to reduce pressure and increase temperature to evaporate, and the low-temperature evaporator stops evaporating during the wastewater discharge process. Continuous evaporation means that after the amount of wastewater in the low-temperature evaporator is lower than the standard scale, the low-temperature evaporator is replenished with liquid, and the low-temperature evaporator still maintains the wastewater evaporation during the wastewater in and out process. Continuous evaporation is more efficient than intermittent evaporation. However, due to the large difference between the temperature of the wastewater itself and the temperature in the low-temperature evaporator, the temperature in the low-temperature evaporator will fluctuate during the inlet and outlet period. If the temperature in the low-temperature evaporator during the inlet and outlet period cannot be accurately controlled, the evaporation and filtration efficiency of the wastewater will also be affected. At present, the temperature control system of the low-temperature evaporator lacks intelligence and predictiveness. When the temperature fluctuates below the boiling point, the temperature control system responds slowly to the temperature rise, thereby affecting the evaporation efficiency of the low-temperature evaporator for wastewater. To this end, we propose a vacuum control system for a low-temperature evaporator and a control method thereof. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the deficiencies in the prior art, the present invention provides a low-temperature evaporator vacuum control system and a control method thereof to solve the above-mentioned problems in the prior art.

[0006] (II) Technical solution

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions: A low-temperature evaporator vacuum control system, including the following modules:

[0008] A temperature database building module is used to obtain the historical feed wastewater temperature, obtain the historical temperature difference, establish a temperature database, and store the historical feed wastewater temperature and the historical temperature difference in the temperature database;

[0009] The temperature data processing module obtains the current feed wastewater temperature, obtains the evaporation boiling point temperature of the current low-temperature evaporator, obtains the reference temperature difference according to the current feed wastewater temperature, the evaporation boiling point temperature of the current low-temperature evaporator and the temperature database, obtains the evaporation boiling point temperature after feeding, obtains the boiling point temperature difference by subtracting the evaporation boiling point temperature after feeding from the evaporation boiling point temperature of the current low-temperature evaporator, and obtains the adjustment temperature by summing the boiling point temperature difference and the reference temperature difference;

[0010] The time data processing module obtains the heating time and the next fluid replenishment start time, and obtains the temperature adjustment time by subtracting the next fluid replenishment end time from the heating time;

[0011] The temperature control execution module obtains the temperature adjustment time and the final temperature, and adjusts the heating temperature of the low-temperature evaporator during the temperature adjustment time so that the heating temperature of the low-temperature evaporator is adjusted to the final temperature. When the temperature in the low-temperature evaporator rises again, the heating temperature of the high-temperature evaporator is reduced to the evaporation boiling point temperature of the current low-temperature evaporator.

[0012] Preferably, the historical temperature difference is obtained in the temperature database building module, specifically:

[0013] Step 1: Obtain the temperature in the evaporator before the historical feed wastewater evaporates, and obtain the historical evaporation boiling point temperature of the feed wastewater;

[0014] Step 2: Subtract the historical boiling point temperature of the evaporation of the feed wastewater from the temperature in the evaporator before the evaporation of the historical feed wastewater to obtain the historical temperature difference;

[0015] Step 3: The historical temperature of the evaporator before the evaporation of the feed wastewater and the historical boiling point temperature of the evaporation of the feed wastewater are stored in the temperature database.

[0016] Preferably, the current feed wastewater temperature is obtained in the temperature data processing module, the evaporation boiling point temperature of the current low-temperature evaporator is obtained, and the reference temperature difference is obtained according to the current feed wastewater temperature, the evaporation boiling point temperature of the current low-temperature evaporator and the temperature database, specifically:

[0017] Step 1: Obtain the current feed wastewater temperature, obtain the evaporation boiling point temperature of the current low-temperature evaporator, and obtain all historical feed wastewater temperatures in the temperature database;

[0018] Step 2: Determine whether there is a feed wastewater temperature that is the same as the current feed wastewater temperature among all historical feed wastewater temperatures;

[0019] If it exists, then all the historical feed wastewater temperatures, the corresponding historical feed wastewater evaporation boiling point temperatures and the corresponding historical temperature differences are captured, and the historical feed wastewater evaporation boiling point temperature closest to the evaporation boiling point temperature of the current low-temperature evaporator is captured among the historical feed wastewater evaporation boiling point temperatures, and the corresponding historical temperature difference is marked and recorded as the reference temperature difference;

[0020] If it does not exist, then capture the two historical feed wastewater temperatures closest to the current feed wastewater temperature among all historical feed wastewater temperatures, mark them as the feed wastewater temperatures to be selected, and sum and average the historical temperature differences corresponding to the two feed wastewater temperatures to be selected to obtain the reference temperature difference.

[0021] Preferably, the evaporation boiling point temperature after feeding is obtained in the temperature data processing module, specifically:

[0022] Step 1: obtaining the pressure before feeding into the low-temperature evaporator, obtaining the pressure after feeding into the low-temperature evaporator, and obtaining the evaporation boiling point temperature of the current low-temperature evaporator;

[0023] Step 2: The evaporation boiling point temperature after feeding is obtained by using the Clapeyron-Clausius formula through the pressure after feeding into the low-temperature evaporator, the pressure before feeding into the low-temperature evaporator and the evaporation boiling point temperature of the current low-temperature evaporator.

[0024] Preferably, the heating time is obtained in the time data processing module, specifically:

[0025] Step 1: Obtain the initial temperature of the low-temperature evaporator, set the heating time, turn on the low-temperature evaporator and start heating with the heating time as the heating time, measure the end temperature of the low-temperature evaporator after the heating is completed, and obtain the measured temperature difference by subtracting the end temperature of the low-temperature evaporator from the initial temperature, and then obtain the heating rate by dividing the measured temperature difference by the heating time;

[0026] Step 2: Repeat step 1 three times with different heating times to obtain three heating rates, and average the three heating rates to obtain a heating reference rate;

[0027] Step 3: Obtain the adjustment temperature, obtain the heating reference rate, and obtain the heating time by dividing the adjustment temperature by the heating reference rate.

[0028] Preferably, the next fluid infusion start time is obtained in the time data processing module, specifically:

[0029] Step 1: After the low-temperature evaporator closes the wastewater refilling valve, the current time is recorded and marked as the refilling end time. After the low-temperature evaporator opens the wastewater refilling valve next time, the current time is recorded and marked as the refilling start time. The duration of the continuous cycle is obtained by subtracting the refilling start time from the refilling end time.

[0030] Step 2: Repeat step 1 three times to obtain three duration cycles, and average the three duration cycles to obtain the duration of the reference duration cycle for fluid infusion;

[0031] Step 3: Get the last liquid replenishment end time when the low-temperature evaporator is officially working and mark it as the next end time, and get the next liquid replenishment start time by summing the next end time and the reference duration.

[0032] Preferably, the final temperature is obtained in the temperature control execution module, specifically:

[0033] Step 1: Obtain the adjustment temperature, obtain the evaporation boiling point temperature of the current low-temperature evaporator, and obtain the predicted boiling point temperature by summing the adjustment temperature and the evaporation boiling point temperature of the current low-temperature evaporator;

[0034] Step 2: Set the fault tolerance temperature to 7°C, and obtain the final temperature by summing the fault tolerance temperature and the predicted boiling point temperature.

[0035] A low-temperature evaporator vacuum control system comprises the following steps:

[0036] S1: Obtain historical feed wastewater temperature, obtain historical temperature difference, establish a temperature database, and store the historical feed wastewater temperature and historical temperature difference in the temperature database;

[0037] S2: Obtain the current feed wastewater temperature, obtain the evaporation boiling point temperature of the current low-temperature evaporator, obtain the reference temperature difference according to the current feed wastewater temperature, the evaporation boiling point temperature of the current low-temperature evaporator and the temperature database, obtain the evaporation boiling point temperature after feeding, obtain the boiling point temperature difference by subtracting the evaporation boiling point temperature after feeding from the evaporation boiling point temperature of the current low-temperature evaporator, and obtain the adjustment temperature by summing the boiling point temperature difference and the reference temperature difference;

[0038] S3: Obtain the heating time, obtain the next rehydration start time, and obtain the temperature adjustment time by subtracting the next rehydration end time from the heating time;

[0039] S4: Obtain the temperature adjustment time and the final temperature, and adjust the heating temperature of the low-temperature evaporator during the temperature adjustment time so that the heating temperature of the low-temperature evaporator is adjusted to the final temperature. When the temperature in the low-temperature evaporator rises again, the heating temperature of the low-temperature evaporator is lowered to the evaporation boiling point temperature of the current low-temperature evaporator.

[0040] (III) Beneficial effects

[0041] The present invention provides a low-temperature evaporator vacuum control system and a control method thereof, which have the following beneficial effects:

[0042] In the temperature data processing module of this scheme, the adjustment temperature is obtained by summing the reference temperature difference and the boiling point temperature difference, so as to overcome the boiling point temperature change caused by the pressure change during the material inlet and outlet process, and also overcome the heating temperature affected by the replenishing liquid entering the low-temperature evaporator during the material inlet and outlet process, so as to increase the temperature before replenishing the liquid, so that the temperature is higher than the boiling point temperature during the material inlet and outlet process, so as to facilitate the temperature in the low-temperature evaporator to continuously evaporate and separate the wastewater during the material inlet and outlet process, which is beneficial to avoid the temperature fluctuation in the low-temperature evaporator during the material inlet and outlet process below the boiling point temperature, affecting the evaporation efficiency of the wastewater.

[0043] In the temperature control execution module of this scheme, the heating temperature of the low-temperature evaporator is adjusted to the final temperature by regulating the heating temperature of the low-temperature evaporator during the temperature adjustment time, thereby predicting the liquid replenishment action, and then facilitating the low-temperature evaporator to heat up in advance to overcome the phenomenon that the temperature is lower than the boiling point due to the temperature drop during the liquid replenishment process. When the temperature in the low-temperature evaporator rises again, the heating temperature of the high-temperature evaporator is lowered to the evaporation boiling point temperature of the current low-temperature evaporator, and when the temperature in the low-temperature evaporator continues to rise after being higher than the boiling point after liquid replenishment, the heating temperature is lowered to the boiling point temperature, thereby facilitating the next heating at the time of liquid replenishment, and facilitating the evaporation and separation of wastewater at a lower heating temperature, saving more heating energy, being beneficial to environmental protection and reducing cost consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a structural schematic diagram of a vacuum control system for a low-temperature evaporator of the present invention;

[0045] Figure 2 The present invention is a flowchart of a low-temperature evaporator vacuum control method. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] See also Figure 1-Figure 2 The present invention provides a low-temperature evaporator vacuum control system, comprising the following modules:

[0048] A temperature database building module is used to obtain the historical feed wastewater temperature, obtain the historical temperature difference, establish a temperature database, and store the historical feed wastewater temperature and the historical temperature difference in the temperature database;

[0049] The temperature data processing module obtains the current feed wastewater temperature, obtains the evaporation boiling point temperature of the current low-temperature evaporator, obtains the reference temperature difference according to the current feed wastewater temperature, the evaporation boiling point temperature of the current low-temperature evaporator and the temperature database, obtains the evaporation boiling point temperature after feeding, obtains the boiling point temperature difference by subtracting the evaporation boiling point temperature after feeding from the evaporation boiling point temperature of the current low-temperature evaporator, and obtains the adjustment temperature by summing the boiling point temperature difference and the reference temperature difference;

[0050] The time data processing module obtains the heating time and the next fluid replenishment start time, and obtains the temperature adjustment time by subtracting the next fluid replenishment end time from the heating time;

[0051] The temperature control execution module obtains the temperature adjustment time and the final temperature, and adjusts the heating temperature of the low-temperature evaporator during the temperature adjustment time so that the heating temperature of the low-temperature evaporator is adjusted to the final temperature. When the temperature in the low-temperature evaporator rises again, the heating temperature of the high-temperature evaporator is reduced to the evaporation boiling point temperature of the current low-temperature evaporator.

[0052] In this embodiment, this scheme stores historical data of feed wastewater temperature and temperature difference in the temperature database building module, so as to facilitate data comparison in the subsequent temperature output processing module, thereby facilitating finding the corresponding reference temperature difference according to the feed wastewater temperature, and thus facilitating understanding the influence of different feed wastewater temperatures on the temperature variation;

[0053] In the temperature data processing module of this scheme, the adjustment temperature is obtained by summing the reference temperature difference and the boiling point temperature difference, so as to overcome the boiling point temperature change caused by the pressure change during the material inlet and outlet process, and also overcome the heating temperature affected by the replenishing liquid entering the low-temperature evaporator during the material inlet and outlet process, so as to increase the temperature before replenishing the liquid, so that the temperature is higher than the boiling point temperature during the material inlet and outlet process, and then the temperature in the low-temperature evaporator can continue to evaporate and separate the wastewater during the material inlet and outlet process, which is beneficial to avoid the temperature fluctuation in the low-temperature evaporator during the material inlet and outlet process being lower than the boiling point temperature and affecting the evaporation efficiency of the wastewater;

[0054] In the time data processing module of this scheme, the temperature adjustment time is obtained by the heating time and the next liquid replenishment start time, so as to facilitate the pre-judgment and advance heating of the low-temperature evaporator before the next liquid replenishment, which is beneficial to avoid the temperature in the low-temperature evaporator being lower than the boiling point during the liquid replenishment process, thereby reducing the evaporation and separation efficiency of the wastewater;

[0055] In the temperature control execution module of this scheme, the heating temperature of the low-temperature evaporator is adjusted to the final temperature by regulating the heating temperature of the low-temperature evaporator during the temperature adjustment time, thereby predicting the liquid replenishment action, and then facilitating the low-temperature evaporator to heat up in advance to overcome the phenomenon that the temperature is lower than the boiling point due to the temperature drop during the liquid replenishment process. When the temperature in the low-temperature evaporator rises again, the heating temperature of the high-temperature evaporator is lowered to the evaporation boiling point temperature of the current low-temperature evaporator, and when the temperature in the low-temperature evaporator continues to rise after being higher than the boiling point after liquid replenishment, the heating temperature is lowered to the boiling point temperature, thereby facilitating the next heating at the time of liquid replenishment, and facilitating the evaporation and separation of wastewater at a lower heating temperature, saving more heating energy, being beneficial to environmental protection and reducing cost consumption.

[0056] Get the historical temperature difference in the temperature database building module, specifically:

[0057] Step 1: Obtain the temperature in the evaporator before the historical feed wastewater evaporates, and obtain the historical evaporation boiling point temperature of the feed wastewater;

[0058] Step 2: Subtract the historical boiling point temperature of the evaporation of the feed wastewater from the temperature in the evaporator before the evaporation of the historical feed wastewater to obtain the historical temperature difference;

[0059] Step 3: The historical temperature of the evaporator before the evaporation of the feed wastewater and the historical boiling point temperature of the evaporation of the feed wastewater are stored in the temperature database.

[0060] In this embodiment, the temperature change of feed wastewater of different temperatures in the low-temperature evaporator after entering the low-temperature evaporator can be understood through the historical temperature difference, and the historical temperature in the evaporator before the evaporation of the feed wastewater and the historical evaporation boiling point temperature of the feed wastewater are stored in the temperature database, so as to facilitate the subsequent finding of the influence of feed wastewater of different temperatures on the temperature in the low-temperature evaporator according to the historical temperature in the evaporator before the evaporation of the feed wastewater and the historical evaporation boiling point temperature of the feed wastewater.

[0061] The current feed wastewater temperature is obtained in the temperature data processing module, and the evaporation boiling point temperature of the current low-temperature evaporator is obtained. The reference temperature difference is obtained according to the current feed wastewater temperature, the evaporation boiling point temperature of the current low-temperature evaporator and the temperature database, specifically:

[0062] Step 1: Obtain the current feed wastewater temperature, obtain the evaporation boiling point temperature of the current low-temperature evaporator, and obtain all historical feed wastewater temperatures in the temperature database;

[0063] Step 2: Determine whether there is a feed wastewater temperature that is the same as the current feed wastewater temperature among all historical feed wastewater temperatures;

[0064] If it exists, then all the historical feed wastewater temperatures, the corresponding historical feed wastewater evaporation boiling point temperatures and the corresponding historical temperature differences are captured, and the historical feed wastewater evaporation boiling point temperature closest to the evaporation boiling point temperature of the current low-temperature evaporator is captured among the historical feed wastewater evaporation boiling point temperatures, and the corresponding historical temperature difference is marked and recorded as the reference temperature difference;

[0065] If it does not exist, then capture the two historical feed wastewater temperatures closest to the current feed wastewater temperature among all historical feed wastewater temperatures, mark them as the feed wastewater temperatures to be selected, and sum and average the historical temperature differences corresponding to the two feed wastewater temperatures to be selected to obtain the reference temperature difference.

[0066] In this embodiment, the temperature change at the corresponding boiling point is found in the temperature database through the feed wastewater temperature, so as to facilitate the grasp of the required temperature increase, and then facilitate the subsequent advance temperature increase before the liquid replenishment, so that during the liquid replenishment process, the temperature in the low-temperature evaporator is still higher than the boiling point temperature under the current pressure, so as to facilitate the low-temperature evaporator to continuously evaporate the wastewater.

[0067] The evaporation boiling point temperature after feeding is obtained in the temperature data processing module, specifically:

[0068] Step 1: obtaining the pressure before feeding into the low-temperature evaporator, obtaining the pressure after feeding into the low-temperature evaporator, and obtaining the evaporation boiling point temperature of the current low-temperature evaporator;

[0069] Step 2: The evaporation boiling point temperature after feeding is obtained by using the Clapeyron-Clausius formula through the pressure after feeding into the low-temperature evaporator, the pressure before feeding into the low-temperature evaporator and the evaporation boiling point temperature of the current low-temperature evaporator.

[0070] In this embodiment, the boiling point after the change can be calculated by using the Clapeyron-Clausius formula through the pressure before and after the change and the boiling point before the change, so as to facilitate the grasp of the required temperature increase. It is worth mentioning that the Clapeyron-Clausius formula is also called the Clapeyron-Clausius equation, which is a publicly available prior art, and the specific formula calculation process will not be described in detail here.

[0071] The heating time is obtained in the time data processing module, specifically:

[0072] Step 1: Obtain the initial temperature of the low-temperature evaporator, set the heating time, turn on the low-temperature evaporator and start heating with the heating time as the heating time, measure the end temperature of the low-temperature evaporator after the heating is completed, and obtain the measured temperature difference by subtracting the end temperature of the low-temperature evaporator from the initial temperature, and then obtain the heating rate by dividing the measured temperature difference by the heating time;

[0073] Step 2: Repeat step 1 three times with different heating times to obtain three heating rates, and average the three heating rates to obtain a heating reference rate;

[0074] Step 3: Obtain the adjustment temperature, obtain the heating reference rate, and obtain the heating time by dividing the adjustment temperature by the heating reference rate.

[0075] In this embodiment, the heating rate of the low-temperature evaporator is measured three times through experiments, and then the test results are averaged to obtain the heating reference rate. The heating time is obtained by dividing the adjusted temperature by the heating reference rate, so as to grasp the time required for the low-temperature evaporator to increase the adjusted temperature. This is only for the convenience of planning the heating timing before replenishing the liquid, thereby consuming as little electric energy as possible for heating, and further saving the cost of wastewater evaporation and separation.

[0076] The next fluid infusion start time is obtained in the time data processing module, specifically:

[0077] Step 1: After the low-temperature evaporator closes the wastewater refilling valve, the current time is recorded and marked as the refilling end time. After the low-temperature evaporator opens the wastewater refilling valve next time, the current time is recorded and marked as the refilling start time. The duration of the continuous cycle is obtained by subtracting the refilling start time from the refilling end time.

[0078] Step 2: Repeat step 1 three times to obtain three duration cycles, and average the three duration cycles to obtain the duration of the reference duration cycle for fluid infusion;

[0079] Step 3: Get the last liquid replenishment end time when the low-temperature evaporator is officially working and mark it as the next end time, and get the next liquid replenishment start time by summing the next end time and the reference duration.

[0080] In this embodiment, the duration of the continuous cycle is obtained by subtracting the start time of the refilling and the end time of the refilling, so as to facilitate the grasp of the working time of the low-temperature evaporator from the end of the refilling to the next refilling, and then facilitate the prediction of the next refilling start time based on the last refilling end time, and then facilitate the predictive heating before the next refilling starts to maintain the temperature in the low-temperature evaporator higher than the boiling point temperature that is about to change.

[0081] The final temperature is obtained in the temperature control execution module, specifically:

[0082] Step 1: Obtain the adjustment temperature, obtain the evaporation boiling point temperature of the current low-temperature evaporator, and obtain the predicted boiling point temperature by summing the adjustment temperature and the evaporation boiling point temperature of the current low-temperature evaporator;

[0083] Step 2: Set the fault tolerance temperature to 7°C, and obtain the final temperature by summing the fault tolerance temperature and the predicted boiling point temperature.

[0084] In this embodiment, the specific temperature value that the low-temperature evaporator needs to reach is easily grasped by summing the adjusted temperature with the current boiling point temperature of the low-temperature evaporator, and then the final temperature is obtained by summing the fault-tolerant temperature with the predicted boiling point temperature, which is helpful in avoiding the temperature variation caused by the sealing problem or insulation problem of the low-temperature evaporator. The specific value of the fault-tolerant temperature can be calculated according to the weight analysis method, which will not be elaborated in detail here.

[0085] See also Figure 1-Figure 2 The present invention provides a low-temperature evaporator vacuum control method, comprising the following steps:

[0086] S1: Obtain historical feed wastewater temperature, obtain historical temperature difference, establish a temperature database, and store the historical feed wastewater temperature and historical temperature difference in the temperature database;

[0087] S2: Obtain the current feed wastewater temperature, obtain the evaporation boiling point temperature of the current low-temperature evaporator, obtain the reference temperature difference according to the current feed wastewater temperature, the evaporation boiling point temperature of the current low-temperature evaporator and the temperature database, obtain the evaporation boiling point temperature after feeding, obtain the boiling point temperature difference by subtracting the evaporation boiling point temperature after feeding from the evaporation boiling point temperature of the current low-temperature evaporator, and obtain the adjustment temperature by summing the boiling point temperature difference and the reference temperature difference;

[0088] S3: Obtain the heating time, obtain the next rehydration start time, and obtain the temperature adjustment time by subtracting the next rehydration end time from the heating time;

[0089] S4: Obtain the temperature adjustment time and the final temperature, and adjust the heating temperature of the low-temperature evaporator during the temperature adjustment time so that the heating temperature of the low-temperature evaporator is adjusted to the final temperature. When the temperature in the low-temperature evaporator rises again, the heating temperature of the low-temperature evaporator is lowered to the evaporation boiling point temperature of the current low-temperature evaporator.

[0090] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination thereof. When implemented using software, the above embodiments may be implemented in whole or in part in the form of a computer program product. A person of ordinary skill in the art may appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein may be implemented in electronic hardware, or in a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution.

[0091] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0092] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

Claims

1. A low temperature evaporator vacuum control system, characterized in that: Includes the following modules: A temperature database building module is used to obtain the historical feed wastewater temperature, obtain the historical temperature difference, establish a temperature database, and store the historical feed wastewater temperature and the historical temperature difference in the temperature database; The temperature data processing module obtains the current feed wastewater temperature, obtains the evaporation boiling point temperature of the current low-temperature evaporator, obtains the reference temperature difference according to the current feed wastewater temperature, the evaporation boiling point temperature of the current low-temperature evaporator and the temperature database, obtains the evaporation boiling point temperature after feeding, obtains the boiling point temperature difference by subtracting the evaporation boiling point temperature after feeding from the evaporation boiling point temperature of the current low-temperature evaporator, and obtains the adjustment temperature by summing the boiling point temperature difference and the reference temperature difference; The time data processing module obtains the heating time and the next fluid replenishment start time, and obtains the temperature adjustment time by subtracting the next fluid replenishment end time from the heating time; The temperature control execution module obtains the temperature adjustment time and the final temperature, and adjusts the heating temperature of the low-temperature evaporator during the temperature adjustment time so that the heating temperature of the low-temperature evaporator is adjusted to the final temperature. When the temperature in the low-temperature evaporator rises again, the heating temperature of the low-temperature evaporator is lowered to the evaporation boiling point temperature of the current low-temperature evaporator; Get the historical temperature difference in the temperature database building module, specifically: Step 1: Obtain the temperature in the evaporator before the historical feed wastewater evaporates, and obtain the historical evaporation boiling point temperature of the feed wastewater; Step 2: Subtract the historical boiling point temperature of the evaporation of the feed wastewater from the temperature in the evaporator before the evaporation of the historical feed wastewater to obtain the historical temperature difference; Step 3: The historical temperature of the evaporator before the evaporation of the feed wastewater and the historical boiling point temperature of the evaporation of the feed wastewater are stored in the temperature database.

2. A low-temperature evaporator vacuum control system according to claim 1, characterized in that: The current feed wastewater temperature is obtained in the temperature data processing module, and the evaporation boiling point temperature of the current low-temperature evaporator is obtained. The reference temperature difference is obtained according to the current feed wastewater temperature, the evaporation boiling point temperature of the current low-temperature evaporator and the temperature database, specifically: Step 1: Obtain the current feed wastewater temperature, obtain the evaporation boiling point temperature of the current low-temperature evaporator, and obtain all historical feed wastewater temperatures in the temperature database; Step 2: Determine whether there is a feed wastewater temperature that is the same as the current feed wastewater temperature among all historical feed wastewater temperatures; If it exists, then all the historical feed wastewater temperatures, the corresponding historical feed wastewater evaporation boiling point temperatures and the corresponding historical temperature differences are captured, and the historical feed wastewater evaporation boiling point temperature closest to the evaporation boiling point temperature of the current low-temperature evaporator is captured among the historical feed wastewater evaporation boiling point temperatures, and the corresponding historical temperature difference is marked and recorded as the reference temperature difference; If it does not exist, then capture the two historical feed wastewater temperatures closest to the current feed wastewater temperature among all historical feed wastewater temperatures, mark them as the feed wastewater temperatures to be selected, and sum and average the historical temperature differences corresponding to the two feed wastewater temperatures to be selected to obtain the reference temperature difference.

3. A low temperature evaporator vacuum control system according to claim 1, characterized in that: The evaporation boiling point temperature after feeding is obtained in the temperature data processing module, specifically: Step 1: obtaining the pressure before feeding into the low-temperature evaporator, obtaining the pressure after feeding into the low-temperature evaporator, and obtaining the evaporation boiling point temperature of the current low-temperature evaporator; Step 2: The evaporation boiling point temperature after feeding is obtained by using the Clapeyron-Clausius formula through the pressure after feeding into the low-temperature evaporator, the pressure before feeding into the low-temperature evaporator and the evaporation boiling point temperature of the current low-temperature evaporator.

4. A low temperature evaporator vacuum control system according to claim 1, characterized in that: The heating time is obtained in the time data processing module, specifically: Step 1: Obtain the initial temperature of the low-temperature evaporator, set the heating time, turn on the low-temperature evaporator and start heating with the heating time as the heating time, measure the end temperature of the low-temperature evaporator after the heating is completed, and obtain the measured temperature difference by subtracting the end temperature of the low-temperature evaporator from the initial temperature, and then obtain the heating rate by dividing the measured temperature difference by the heating time; Step 2: Repeat step 1 three times with different heating times to obtain three heating rates, and average the three heating rates to obtain a heating reference rate; Step 3: Obtain the adjustment temperature, obtain the heating reference rate, and obtain the heating time by dividing the adjustment temperature by the heating reference rate.

5. A low temperature evaporator vacuum control system according to claim 1, characterized in that: The next fluid infusion start time is obtained in the time data processing module, specifically: Step 1: After the low-temperature evaporator closes the wastewater refilling valve, the current time is recorded and marked as the refilling end time. After the low-temperature evaporator opens the wastewater refilling valve next time, the current time is recorded and marked as the refilling start time. The duration of the continuous cycle is obtained by subtracting the refilling start time from the refilling end time. Step 2: Repeat step 1 three times to obtain three duration cycles, and average the three duration cycles to obtain the duration of the reference duration cycle for fluid infusion; Step 3: Get the last liquid replenishment end time when the low-temperature evaporator is officially working and mark it as the next end time, and get the next liquid replenishment start time by summing the next end time and the reference duration.

6. A low-temperature evaporator vacuum control system according to claim 1, characterized in that: The final temperature is obtained in the temperature control execution module, specifically: Step 1: Obtain the adjustment temperature, obtain the evaporation boiling point temperature of the current low-temperature evaporator, and obtain the predicted boiling point temperature by summing the adjustment temperature and the evaporation boiling point temperature of the current low-temperature evaporator; Step 2: Set the fault tolerance temperature to 7°C, and obtain the final temperature by summing the fault tolerance temperature and the predicted boiling point temperature.

7. A low-temperature evaporator vacuum control method, applied to a low-temperature evaporator vacuum control system according to any one of claims 1 to 6, characterized in that: The steps include: S1: Obtain historical feed wastewater temperature, obtain historical temperature difference, establish a temperature database, and store the historical feed wastewater temperature and historical temperature difference in the temperature database; S2: Obtain the current feed wastewater temperature, obtain the evaporation boiling point temperature of the current low-temperature evaporator, obtain the reference temperature difference according to the current feed wastewater temperature, the evaporation boiling point temperature of the current low-temperature evaporator and the temperature database, obtain the evaporation boiling point temperature after feeding, obtain the boiling point temperature difference by subtracting the evaporation boiling point temperature after feeding from the evaporation boiling point temperature of the current low-temperature evaporator, and obtain the adjustment temperature by summing the boiling point temperature difference and the reference temperature difference; S3: Obtain the heating time, obtain the next rehydration start time, and obtain the temperature adjustment time by subtracting the next rehydration end time from the heating time; S4: Obtain the temperature adjustment time and the final temperature, and adjust the heating temperature of the low-temperature evaporator during the temperature adjustment time so that the heating temperature of the low-temperature evaporator is adjusted to the final temperature. When the temperature in the low-temperature evaporator rises again, the heating temperature of the low-temperature evaporator is lowered to the evaporation boiling point temperature of the current low-temperature evaporator.

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