MVR waste liquid evaporator steam heat utilization method for efficient wastewater treatment

Abstract

The invention discloses an MVR waste liquid evaporator steam heat utilization method for efficient wastewater treatment, and relates to the field of steam heat utilization, and the method comprises the following steps: setting basic parameters of a steam heat circulation system of an MVR device based on an actual equipment type and a wastewater treatment scale; a compressor is started for preheating, a steam heat circulation system is controlled to be started for the first time, and the initial temperature of steam entering an evaporator reaches the initial temperature of steam heat exchange operation; monitoring and analyzing a steam flow curve of a steam backflow pipeline, adjusting the power of a compressor, and adjusting the initial temperature of steam; when the steam heat circulation system does not meet the heat load requirement of heat exchange treatment, distilled water is connected into the vacuum pump through a condensation backflow pipeline to be reheated to supplement steam; and carrying out jitter analysis and polynomial fitting on real-time flow data of the real-time steam flow curve, and taking the fitted data as a supplement amount adjustment basis of distilled water in the steam heat circulation system.

Description

Technical Field

[0001] The invention relates to the field of steam heat utilization, and in particular to a steam heat utilization method of an MVR waste liquid evaporator for efficient waste water treatment. Background Art

[0002] During the wastewater treatment process, the MVR (mechanical vapor recompression) device uses the steam heat circulation system to recover heat energy to achieve efficient evaporation and concentration. No external energy is required. The steam evaporated from the wastewater is treated and then re-connected to the evaporator to achieve self-circulation of wastewater treatment steam. However, there are significant differences in the requirements for evaporation temperature, steam flow and heat load for different wastewater treatment scales. During operation, the steam flow may cause insufficient heat load due to fluctuations in compressor performance or changes in wastewater treatment load. To solve this problem, distilled water is introduced into the vacuum pump through the condensation reflux pipe to heat and generate steam to dynamically supplement heat. At the same time, in order to solve the common high-frequency jitter problem in steam flow monitoring, the flow curve is optimized through real-time data analysis and polynomial fitting, and the fitting results are used as the basis for adjusting the amount of distilled water replenishment to ensure precise control and heat balance of the steam circulation system.

[0003] To this end, a steam heat utilization solution for MVR waste liquid evaporator for efficient wastewater treatment is proposed, which significantly improves the operating efficiency and reliability of the steam heat circulation system and meets the needs of complex wastewater treatment scenarios. Summary of the invention

[0004] In order to solve the above technical problems, a method for utilizing steam heat of an MVR waste liquid evaporator for efficient wastewater treatment is provided. This technical solution solves the problems raised in the above background technology.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0006] A method for utilizing steam heat of an MVR waste liquid evaporator for efficient wastewater treatment, comprising:

[0007] Based on the actual equipment type and wastewater treatment scale, the basic parameters of the steam heat circulation system of the MVR device are set;

[0008] Start the compressor preheating and control the steam heat circulation system for initial startup, so that the initial temperature of the steam entering the evaporator reaches the initial temperature of the steam heat exchange operation;

[0009] Monitor and analyze the steam flow curve of the steam return pipeline, adjust the compressor power, and adjust the initial steam temperature;

[0010] When the steam heat circulation system fails to meet the heat load requirement of the heat exchange treatment, the distilled water is connected to the vacuum pump through the condensation reflux pipeline to reheat and supplement the steam;

[0011] The real-time flow data of the real-time steam flow curve is subjected to jitter analysis and polynomial fitting, and the fitted data is used as the basis for adjusting the supplementary amount of distilled water in the steam heat circulation system.

[0012] Preferably, the basic parameter setting of the steam heat circulation system of the MVR device based on the actual equipment type and wastewater treatment scale specifically includes:

[0013] Obtain basic equipment model parameters of the MVR device and its corresponding external components, including device size, material, and compressor power;

[0014] With the evaporator as the processing core and the compressor as the energy source, the evaporator, vacuum pump and compressor are connected in a loop. At the same time, the evaporator is connected to the wastewater tank, distillation tank and concentrate tank to form a steam heat circulation system.

[0015] Based on the material information of the evaporator device, the initial operating temperature and the maximum operating temperature during the steam heat exchange operation are set, and based on the size information of the evaporator device, the initial treatment scale of the evaporator for treating wastewater is set;

[0016] The wastewater in the wastewater tank is connected to the evaporator until the initial treatment scale of the wastewater is reached, and then all channels of the steam heat circulation system are closed, and the air in the evaporator is extracted to make the evaporator reach a vacuum state.

[0017] Preferably, the starting of the compressor preheating and controlling the steam heat circulation system to start up for the first time so that the initial temperature of the steam entering the evaporator reaches the initial temperature of the steam heat exchange operation specifically includes:

[0018] Inject distilled water in the same amount as the initial wastewater treatment scale into the vacuum pump, compress the air through the compressor to generate heat, heat the water in the vacuum pump to boiling to generate steam, and at the same time, the compressor pressurizes the steam to one atmosphere;

[0019] A temperature sensor is installed at the connection port between the vacuum pump and the evaporator to monitor the steam temperature at the connection port in real time. When the steam temperature at the connection port reaches the initial temperature of the steam heat exchange operation, all channels of the steam heat circulation system are opened;

[0020] The steam provides heat to exchange heat with the wastewater in the evaporator. The wastewater in the evaporator under vacuum absorbs heat and evaporates. The steam returns to the vacuum pump through the loop between the evaporator and the vacuum pump. At the same time, the distilled water after the steam condenses is connected to the distillation tank, and the remaining concentrated wastewater in the evaporator is connected to the concentrate tank.

[0021] A steam flow monitoring device is provided in the steam return pipe in the loop between the evaporator and the vacuum pump to monitor in real time the flow of the return steam when the steam heat circulation system is first started.

[0022] Preferably, the monitoring and analyzing of the steam flow curve of the steam return pipeline, adjusting the compressor power, and adjusting the initial temperature of the steam specifically include:

[0023] Setting the initial startup monitoring time window of the steam heat circulation system, collecting steam flow data of the steam flow monitoring device within the time window, and establishing a steam flow change curve of the initial startup process based on the collected real-time time series data;

[0024] Observe whether there is an obvious peak in the steam flow rate change curve. If so, it is judged that the initial temperature of the steam entering the evaporator is too low, and the output power of the compressor is adjusted to perform equidistant step-by-step temperature increase on the steam.

[0025] The steam flow rate change curve is continuously monitored with each step of the temperature rise process as a monitoring cycle, and the compressor output power is adjusted until the curve no longer has an obvious peak;

[0026] When the steam temperature after the heating treatment has risen to the maximum operating temperature of the evaporator steam heat exchange, and the steam flow change curve still has an obvious peak, it is determined that the steam heat circulation system has not met the heat load demand of the heat exchange treatment.

[0027] Preferably, when the steam heat circulation system fails to meet the heat load requirement of the heat exchange treatment, the distilled water is connected to the vacuum pump through the condensation reflux pipeline to reheat and supplement the steam, which specifically includes:

[0028] Based on the steam flow rate change curve corresponding to the last monitoring cycle of the stepped temperature rise, the difference between the peak value of the steam flow rate in the steam flow rate change curve and the latest flow rate data of the curve is calculated and marked as the flow rate difference after heat exchange;

[0029] Calculate the steam loss according to the flow difference after heat exchange, and then calculate the heat load demand deficiency of the actual steam heat circulation system;

[0030] Based on the law of conservation of heat, the amount of distilled water that needs to be supplemented corresponding to the flow difference after steam heat exchange is calculated, the supplementary distilled water is connected to the vacuum pump through the condensation reflux pipe, heated by the compressor, and the steam generated by the heating is added to the steam heat circulation system as supplementary steam;

[0031] The specific calculation method for the amount of distilled water added is:

[0032]

[0033] In the formula, m wis the amount of distilled water replenishment, Q is the heat load demand shortfall, T s , T w are the maximum operating temperature of steam heat exchange and the temperature of supplementary distilled water, c is the specific heat capacity of water, L is the latent heat of vaporization of water, M is the mass flow rate of steam, and h is the specific enthalpy of steam.

[0034] Preferably, the jitter analysis and polynomial fitting of the real-time flow data of the real-time steam flow curve and using the fitted data as a basis for adjusting the supplementary amount of distilled water in the steam heat circulation system specifically include:

[0035] Obtain the steam flow change curve of the steam heat circulation system during the initial startup process, set the sliding window size with the initial monitoring position as the starting point, and move back one index subscript each time until the window reaches the last monitoring point;

[0036] Calculate the variance mean of the time series steam flow value in each sliding window and mark it as a stable reference value;

[0037] Real-time monitoring of steam flow builds a real-time steam flow curve. According to the set sliding window size, the jitter assessment segment of the steam flow curve is established with the latest monitoring point of the current real-time steam flow curve as the end point, and the variance within the jitter assessment segment is calculated;

[0038] When the variance within the evaluation segment is greater than or equal to the stable reference value, it is marked as steam flow curve jitter. Based on the Savitzky-Golay filtering algorithm, the fluctuation of the latest monitoring point is eliminated through polynomial fitting, and distilled water supplementation is adjusted according to the steam flow corresponding to the latest monitoring point after the fluctuation is eliminated.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The basic parameters are set based on the scale of wastewater treatment, so that the steam temperature, flow rate and pressure can be more accurately adapted to the concentration requirements of different wastewaters, ensuring the maximum heat exchange efficiency of the evaporator; secondly, through compressor preheating and initial startup control, the steam heat cycle is quickly established to achieve efficient startup, shorten the equipment preheating time, and improve energy utilization; thirdly, the flow curve of the steam return pipeline is dynamically monitored and adjusted, and the flow jitter problem is eliminated by combining polynomial fitting, making the steam flow control more stable, thereby optimizing the temperature control accuracy; in addition, when the heat load is insufficient, the distilled water is supplemented by condensation reflux for secondary heating to generate steam, which can timely supplement the heat gap and ensure the wastewater concentration efficiency and product quality. Overall, the system reduces heat waste, improves heat recovery efficiency, reduces equipment operation energy consumption and cost, and enhances the adaptability of wastewater treatment, especially under conditions with large dynamic load fluctuations, showing excellent stability and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a flow chart of a method for utilizing steam heat from an MVR waste liquid evaporator for efficient waste water treatment according to the present invention;

[0042] Figure 2 This is a flow chart of basic parameter setting for the steam heat circulation system of the MVR device based on the actual equipment type and wastewater treatment scale of the present invention;

[0043] Figure 3 The present invention starts the compressor preheating, controls the steam heat circulation system to start for the first time, and makes the initial temperature of the steam entering the evaporator reach the initial temperature flow chart of the steam heat exchange operation;

[0044] Figure 4 A flow chart for monitoring and analyzing the steam flow curve of the steam return pipeline, adjusting the compressor power, and adjusting the initial steam temperature according to the present invention;

[0045] Figure 5 This is a flow chart of the present invention in which when the steam heat circulation system fails to meet the heat load requirement of the heat exchange treatment, distilled water is connected to the vacuum pump through the condensation reflux pipeline to reheat and supplement steam;

[0046] Figure 6 The present invention performs jitter analysis and polynomial fitting on the real-time flow data of the real-time steam flow curve, and uses the fitted data as a flow chart for adjusting the supplementary amount of distilled water in the steam heat circulation system. DETAILED DESCRIPTION

[0047] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art may think of other obvious variations.

[0048] Reference Figure 1 As shown, a method for utilizing steam heat of an MVR waste liquid evaporator for efficient wastewater treatment includes:

[0049] Based on the actual equipment type and wastewater treatment scale, the basic parameters of the steam heat circulation system of the MVR device are set;

[0050] Start the compressor preheating and control the steam heat circulation system for initial startup so that the initial temperature of the steam entering the evaporator reaches the initial temperature of the steam heat exchange operation;

[0051] Monitor and analyze the steam flow curve of the steam return pipeline, adjust the compressor power, and adjust the initial steam temperature;

[0052] When the steam heat circulation system fails to meet the heat load requirement of the heat exchange treatment, the distilled water is connected to the vacuum pump through the condensation reflux pipeline to reheat and supplement the steam;

[0053] The real-time flow data of the real-time steam flow curve is subjected to jitter analysis and polynomial fitting, and the fitted data is used as the basis for adjusting the supplementary amount of distilled water in the steam heat circulation system.

[0054] Reference Figure 2 As shown in the figure, based on the actual equipment type and wastewater treatment scale, the basic parameter settings for the steam heat circulation system of the MVR device include:

[0055] Obtain basic equipment model parameters of the MVR device and its corresponding external components, including device size, material, and compressor power;

[0056] With the evaporator as the processing core and the compressor as the energy source, the evaporator, vacuum pump and compressor are connected in a loop. At the same time, the evaporator is connected to the wastewater tank, distillation tank and concentrate tank to form a steam heat circulation system.

[0057] Based on the material information of the evaporator device, the initial operating temperature (set to 100 degrees Celsius in this embodiment) and the maximum operating temperature (set to 120 degrees Celsius in this embodiment) during the steam heat exchange operation are set, and based on the size information of the evaporator device, the initial treatment scale of the evaporator for treating wastewater is set;

[0058] The wastewater in the wastewater tank is connected to the evaporator until the initial treatment scale of the wastewater is reached, and then all channels of the steam heat circulation system are closed, and the air in the evaporator is extracted to make the evaporator reach a vacuum state.

[0059] Wastewater evaporates at about 85 degrees Celsius under vacuum. When heat loss is controllable, the steam generated by wastewater evaporation can be recycled. The ideal workflow of its complete structure is:

[0060] The compressor is driven by the only power source to heat the steam to 100-120 degrees Celsius, and then the steam is passed into the evaporator to exchange heat and light with the wastewater in the evaporator. The steam evaporated from the wastewater under vacuum flows back to the vacuum pump, and the steam is compressed to 1 atmosphere by the compressor and then heated again to form a steam heat cycle. At the same time, the distilled water condensed from the steam in the evaporator is connected to the distillation tank, and the concentrated wastewater is connected to the concentrate tank.

[0061] Reference Figure 3 As shown, start the compressor preheating, control the steam heat circulation system for the initial start-up, and make the initial temperature of the steam entering the evaporator reach the initial temperature of the steam heat exchange operation. Specifically include:

[0062] During the system startup phase, distilled water equal to the initial wastewater treatment scale is precisely injected into the vacuum pump cavity to ensure that the initial amount of steam generated matches the treatment scale. The compressor generates heat through air compression, and the temperature rise of the compressed air in this process is used to gradually heat the distilled water in the vacuum pump to a boiling state. To improve the heating efficiency, a high thermal conductivity coating is set on the inner wall of the vacuum pump cavity to optimize the heat transfer rate by increasing the thermal conductivity.

[0063] A temperature sensor is installed at the connection between the vacuum pump and the evaporator. It uses high-precision thermocouple technology to capture the change in steam temperature at the connection within milliseconds. To ensure the accuracy of the measurement results, the outer layer of the sensor is covered with an anti-corrosion coating and calibrated in real time in combination with a digital algorithm. The steam temperature at the connection is monitored in real time. When the steam temperature at the connection reaches the initial temperature of the steam heat exchange operation, all channels of the steam heat circulation system are opened;

[0064] The steam provides heat to exchange heat with the wastewater in the evaporator. The wastewater in the evaporator under vacuum absorbs heat and evaporates. The steam returns to the vacuum pump through the loop between the evaporator and the vacuum pump. At the same time, the distilled water after the steam condenses is connected to the distillation tank, and the remaining concentrated wastewater in the evaporator is connected to the concentrate tank.

[0065] A steam flow monitoring device is installed in the steam return pipe in the loop between the evaporator and the vacuum pump to monitor in real time the flow of the return steam when the steam heat circulation system is initially started. The flow monitoring device adopts a Coriolis mass flowmeter, which can capture the tiny fluctuations of the steam in the pipe and convert them into high-precision data.

[0066] Reference Figure 4 As shown, monitoring and analyzing the steam flow curve of the steam return pipeline, adjusting the compressor power, and adjusting the initial steam temperature specifically include:

[0067] In order to grasp the dynamic changes of steam flow in real time, a fixed time window needs to be set to ensure that the collected data covers the key change points in the startup process. The specific length is dynamically adjusted according to the equipment specifications and steam generation rate. For example, the time window for a small evaporator is 10s, and the time window for a large evaporator is 30s. The collection frequency is once every 6s.

[0068] Setting the initial startup monitoring time window of the steam heat circulation system, collecting steam flow data of the steam flow monitoring device within the time window, and establishing a steam flow change curve of the initial startup process based on the collected real-time time series data;

[0069] Observe whether there is an obvious peak in the steam flow change curve. If so, it is judged that the initial temperature of the steam entering the evaporator is too low. Adjust the output power of the compressor to perform equidistant step-by-step temperature treatment on the steam. The temperature increase gradient can be flexibly set according to the actual settable upper limit and adjustment accuracy requirements.

[0070] Among them, the obvious peak is usually set as the proportion of the local peak of the curve exceeding the average value of all points. When this proportion reaches 30%, it can be considered an obvious peak. The steam flow change curve represents that the amount of steam generated by the evaporation of wastewater in the evaporator is significantly attenuated relative to its maximum value in the process, which means that the heat carried by the input steam is not enough to meet the actual heat load requirements of wastewater treatment. At this time, the heat carried can only be increased by increasing the steam temperature or increasing the amount of steam entering the evaporator.

[0071] The steam flow rate change curve is continuously monitored with each step of the temperature rise process as a monitoring cycle, and the compressor output power is adjusted until the curve no longer has an obvious peak.

[0072] When the steam temperature after the heating treatment has risen to the maximum operating temperature of the evaporator steam heat exchange, and the steam flow change curve still has an obvious peak, it is determined that the steam heat circulation system has not met the heat load demand of the heat exchange treatment.

[0073] Reference Figure 5 As shown, when the steam heat circulation system does not meet the heat load requirement of the heat exchange treatment, the distilled water is connected to the vacuum pump through the condensation reflux pipeline to reheat and supplement the steam, which specifically includes:

[0074] Based on the steam flow rate change curve corresponding to the last monitoring cycle of the stepped temperature rise, the difference between the peak value of the steam flow rate in the steam flow rate change curve and the latest flow rate data of the curve is calculated and marked as the flow rate difference after heat exchange;

[0075] Calculate the steam loss according to the flow difference after heat exchange, and then calculate the heat load demand deficiency of the actual steam heat circulation system;

[0076] Based on the law of conservation of heat, the amount of distilled water that needs to be supplemented corresponding to the flow difference after steam heat exchange is calculated, the supplementary distilled water is connected to the vacuum pump through the condensation reflux pipe, heated by the compressor, and the steam generated by the heating is added to the steam heat circulation system as supplementary steam;

[0077] The specific calculation method for the amount of distilled water added is:

[0078]

[0079] In the formula, m w is the amount of distilled water added, in kg / s, Q is the heat load demand shortfall, T s , T w are the maximum operating temperature of steam heat exchange and the temperature of supplementary distilled water, c is the specific heat capacity of water, L is the latent heat of vaporization of water, M is the mass flow loss of steam, and h is the specific enthalpy of steam. The following is a specific calculation example:

[0080] Assuming the known conditions, the current steam temperature is 100 degrees Celsius, the initial temperature of the supplementary distilled water is 25 degrees Celsius, the latent heat of vaporization of water and the specific heat capacity of water are 2257 kJ / kg·℃ respectively, and the amount of supplementary steam is 1 kg, the calculation process is: Divide the result by the thermal conversion efficiency to get the final result, which is the amount of distilled water to be replenished.

[0081] Reference Figure 6 As shown, jitter analysis and polynomial fitting are performed on the real-time flow data of the real-time steam flow curve, and the fitted data is used as the basis for adjusting the supplementary amount of distilled water in the steam heat circulation system. Specifically, the following are included:

[0082] In this step, an innovative real-time monitoring and dynamic compensation method is designed, which combines the sliding window variance analysis and Savitzky-Golay filtering algorithm to detect and correct the flow curve jitter in real time.

[0083] Obtain the steam flow change curve of the steam heat circulation system during the initial startup process, set the sliding window size with the initial monitoring position as the starting point, and move back one index subscript each time until the window reaches the last monitoring point;

[0084] Calculate the variance mean of the time series steam flow value in each sliding window and mark it as a stable reference value;

[0085] Real-time monitoring of steam flow builds a real-time steam flow curve. According to the set sliding window size, the jitter assessment segment of the steam flow curve is established with the latest monitoring point of the current real-time steam flow curve as the end point, and the variance within the jitter assessment segment is calculated;

[0086] When the variance in the evaluation segment is greater than or equal to the stable reference value, it is marked as steam flow curve jitter. Based on the Savitzky-Golay filtering algorithm, the fluctuation of the latest monitoring point is eliminated through polynomial fitting, and the distilled water supplement adjustment is performed according to the steam flow corresponding to the latest monitoring point after the fluctuation is eliminated. The following is a specific example:

[0087] A set of raw data collected in the actual operation is [10.0, 10.2, 10.4, 10.1, 9.8, 11.2, 15.0]. The sliding window size n is set to 5, and the second-order polynomial fitting is selected to construct the fitting matrix. The Vandermonde matrix is:

[0088] Next, the Vandermonde matrix pseudo-inverse is calculated using the formula V T V) -1 V T, the filter weight matrix is ​​calculated as: W = [-3 / 35, 12 / 35, -3 / 35, 12 / 35, 17 / 35], and the smoothing value of the last point 15.0 of the original data is calculated as: -3 / 35*10.0+12 / 35*10.2+-3 / 35*10.1+12 / 35*10.4+17 / 35*15.0=12.6257, that is, the value of the nearest monitoring point after fluctuation elimination is 12.6257. Based on this value, the real-time flow difference after heat exchange is calculated, and the real-time distilled water replenishment demand is calculated by the distilled water replenishment calculation formula, and the distilled water replenishment demand is adjusted dynamically in real time.

[0089] The above calculation method effectively improves the stability of steam flow data. At the same time, the amount of distilled water replenishment is dynamically adjusted based on smooth data to ensure that the steam heat circulation system can quickly reach a stable operating state during the initial startup phase. This method innovatively combines time series analysis and filtering technology, which can significantly improve the system's real-time response capability and control accuracy.

[0090] Furthermore, the present invention also proposes a storage medium for a method for utilizing steam heat of an MVR waste liquid evaporator for efficient wastewater treatment, on which a computer-readable program is stored. When the computer-readable program is called, the above-mentioned method for utilizing steam heat of an MVR waste liquid evaporator for efficient wastewater treatment is executed.

[0091] It is understandable that the storage medium may be a magnetic medium, such as a floppy disk, a hard disk, or a magnetic tape; an optical medium, such as a DVD; or a semiconductor medium, such as a solid state drive (SSD).

[0092] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions only describe the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for utilizing steam heat from an MVR waste liquid evaporator for efficient wastewater treatment, characterized in that: include: Based on the actual equipment type and wastewater treatment scale, the basic parameters of the steam heat circulation system of the MVR device are set; Start the compressor preheating and control the steam heat circulation system for initial startup so that the initial temperature of the steam entering the evaporator reaches the initial temperature of the steam heat exchange operation; Monitor and analyze the steam flow curve of the steam return pipeline, adjust the compressor power, and adjust the initial steam temperature; When the steam heat circulation system fails to meet the heat load requirement of the heat exchange treatment, the distilled water is connected to the vacuum pump through the condensation reflux pipeline to reheat and supplement the steam; The real-time flow data of the real-time steam flow curve is subjected to jitter analysis and polynomial fitting, and the fitted data is used as the basis for adjusting the supplementary amount of distilled water in the steam heat circulation system.

2. The method for utilizing steam heat of an MVR waste liquid evaporator for efficient wastewater treatment according to claim 1, characterized in that: The basic parameter setting of the steam heat circulation system of the MVR device based on the actual equipment type and wastewater treatment scale specifically includes: Obtain basic equipment model parameters of the MVR device and its corresponding external components, including device size, material, and compressor power; With the evaporator as the processing core and the compressor as the energy source, the evaporator, vacuum pump and compressor are connected in a loop. At the same time, the evaporator is connected to the wastewater tank, distillation tank and concentrate tank to form a steam heat circulation system. Based on the material information of the evaporator device, the initial operating temperature and the maximum operating temperature during the steam heat exchange operation are set, and based on the size information of the evaporator device, the initial treatment scale of the evaporator for treating wastewater is set; The wastewater in the wastewater tank is connected to the evaporator until the initial treatment scale of the wastewater is reached, and then all channels of the steam heat circulation system are closed, and the air in the evaporator is extracted to make the evaporator reach a vacuum state.

3. The method for utilizing steam heat of an MVR waste liquid evaporator for efficient wastewater treatment according to claim 2, characterized in that: The starting of the compressor preheating and controlling the steam heat circulation system for initial startup so that the initial temperature of the steam entering the evaporator reaches the initial temperature of the steam heat exchange operation specifically includes: Inject distilled water in the same amount as the initial wastewater treatment scale into the vacuum pump, compress the air through the compressor to generate heat, heat the water in the vacuum pump to boiling to generate steam, and at the same time, the compressor pressurizes the steam to one atmosphere; A temperature sensor is installed at the connection port between the vacuum pump and the evaporator to monitor the steam temperature at the connection port in real time. When the steam temperature at the connection port reaches the initial temperature of the steam heat exchange operation, all channels of the steam heat circulation system are opened; The steam provides heat to exchange heat with the wastewater in the evaporator. The wastewater in the evaporator under vacuum absorbs heat and evaporates. The steam returns to the vacuum pump through the loop between the evaporator and the vacuum pump. At the same time, the distilled water after the steam condenses is connected to the distillation tank, and the remaining concentrated wastewater in the evaporator is connected to the concentrate tank. A steam flow monitoring device is provided in the steam return pipe in the loop between the evaporator and the vacuum pump to monitor in real time the flow of the return steam when the steam heat circulation system is first started.

4. The method for utilizing steam heat of an MVR waste liquid evaporator for efficient wastewater treatment according to claim 3 is characterized in that: The monitoring and analyzing of the steam flow curve of the steam return pipeline, adjusting the compressor power, and adjusting the initial temperature of the steam specifically include: Setting the initial startup monitoring time window of the steam heat circulation system, collecting steam flow data of the steam flow monitoring device within the time window, and establishing a steam flow change curve of the initial startup process based on the collected real-time time series data; Observe whether there is an obvious peak in the steam flow rate change curve. If so, it is judged that the initial temperature of the steam entering the evaporator is too low, and the output power of the compressor is adjusted to perform equidistant step-by-step temperature increase on the steam. The steam flow rate change curve is continuously monitored with each step of the temperature rise process as a monitoring cycle, and the compressor output power is adjusted until the curve no longer has an obvious peak; When the steam temperature after the heating treatment has risen to the maximum operating temperature of the evaporator steam heat exchange, and the steam flow change curve still has an obvious peak, it is determined that the steam heat circulation system has not met the heat load demand of the heat exchange treatment.

5. The method for utilizing steam heat of an MVR waste liquid evaporator for efficient wastewater treatment according to claim 4, characterized in that: When the steam heat circulation system fails to meet the heat load requirement of the heat exchange treatment, the distilled water is connected to the vacuum pump through the condensation reflux pipeline to reheat and supplement the steam, which specifically includes: Based on the steam flow rate change curve corresponding to the last monitoring cycle of the stepped temperature rise, the difference between the peak value of the steam flow rate in the steam flow rate change curve and the latest flow rate data of the curve is calculated and marked as the flow rate difference after heat exchange; Calculate the steam loss according to the flow difference after heat exchange, and then calculate the heat load demand deficiency of the actual steam heat circulation system; Based on the law of conservation of heat, the amount of distilled water that needs to be supplemented corresponding to the flow difference after steam heat exchange is calculated, the supplementary distilled water is connected to the vacuum pump through the condensation reflux pipe, heated by the compressor, and the steam generated by the heating is added to the steam heat circulation system as supplementary steam; The specific calculation method for the amount of distilled water added is: In the formula, m w is the amount of distilled water replenishment, Q is the heat load demand shortfall, T s 、T w are the maximum operating temperature of steam heat exchange and the temperature of supplementary distilled water, c is the specific heat capacity of water, L is the latent heat of vaporization of water, M is the mass flow rate of steam, and h is the specific enthalpy of steam.

6. The method for utilizing steam heat of an MVR waste liquid evaporator for efficient wastewater treatment according to claim 5, characterized in that: The jitter analysis and polynomial fitting of the real-time flow data of the real-time steam flow curve and using the fitted data as a basis for adjusting the supplementary amount of distilled water in the steam heat circulation system specifically include: Obtain the steam flow change curve of the steam heat circulation system during the initial startup process, set the sliding window size with the initial monitoring position as the starting point, and move back one index subscript each time until the window reaches the last monitoring point; Calculate the variance mean of the time series steam flow value in each sliding window and mark it as a stable reference value; Real-time monitoring of steam flow builds a real-time steam flow curve. According to the set sliding window size, the jitter assessment segment of the steam flow curve is established with the latest monitoring point of the current real-time steam flow curve as the end point, and the variance within the jitter assessment segment is calculated; When the variance within the evaluation segment is greater than or equal to the stable reference value, it is marked as steam flow curve jitter. Based on the Savitzky-Golay filtering algorithm, the fluctuation of the latest monitoring point is eliminated through polynomial fitting, and distilled water supplementation is adjusted according to the steam flow corresponding to the latest monitoring point after the fluctuation is eliminated.

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