A flushing control method for ultrafiltration flushing system

Abstract

The present invention relates to the technical field of flushing data processing, and specifically to a flushing control method for an ultrafiltration flushing system. The present invention analyzes the distribution of data points on a multidimensional data curve within each time range to obtain the degree of ultrafiltration membrane contamination in each time period of the curve; judges whether to perform backwashing at the real time according to the degree of ultrafiltration membrane contamination in the real-time curve time period, and obtains the flushing increase intensity of the real-time backwashing according to the degree of ultrafiltration membrane contamination in the curve time period corresponding to the real-time backwashing, the degree of ultrafiltration membrane contamination in the adjacent curve time period corresponding to the previous backwashing, and the time distance between the real-time backwashing and the previous backwashing; obtains the flushing intensity of the real-time backwashing in combination with the initial flushing intensity, and judges whether to perform chemical flushing at the real time; and controls the flushing of the ultrafiltration membrane at the real time according to the judgment result. The present invention improves the effect of flushing ultrafiltration membrane pollution by obtaining an accurate flushing time.

Description

Technical Field

[0001] The invention relates to the technical field of flushing data processing, and in particular to a flushing control method for an ultrafiltration flushing system. Background Art

[0002] The ultrafiltration flushing system is a system based on ultrafiltration membrane to filter out tiny particles and microorganisms such as bacteria in the water. With the use of ultrafiltration membrane, pollutants such as organic matter, inorganic matter, and microorganisms may accumulate on the membrane surface or in the pores to form a pollution layer, reducing the permeability and retention effect of the membrane and deteriorating the effluent water quality; therefore, the ultrafiltration membrane needs to be flushed and maintained.

[0003] In the prior art, the ultrafiltration membrane is usually flushed during the initial operation of the ultrafiltration membrane, and then a fixed flushing cycle is set according to human experience to flush the ultrafiltration membrane; however, in the actual working process, considering that the unstable inlet flow rate of raw water may cause pollutants to be more easily deposited on the surface of the ultrafiltration membrane or clog the membrane pores, and the change in water temperature affects the viscosity of water molecules, which may cause changes in the performance of the membrane material, the degree to which the ultrafiltration membrane needs to be flushed at different stages is different, resulting in the traditional fixed flushing cycle being unable to adapt to actual changes, which may reduce the filtration efficiency and service life of the ultrafiltration membrane, and the flushing effect is poor. Summary of the invention

[0004] In order to solve the technical problem that the degree of flushing required for ultrafiltration membranes at different stages is different, resulting in the inability of traditional fixed flushing cycles to adapt to actual changes, the purpose of the present invention is to provide a flushing control method for an ultrafiltration flushing system, and the technical solution adopted is as follows:

[0005] The present invention proposes a flushing control method for an ultrafiltration flushing system, the method comprising:

[0006] Real-time acquisition of multi-dimensional data curves of the ultrafiltration flushing system at each time range after initial flushing, wherein the multi-dimensional data curves include: water temperature curve, water production rate curve and water clarity curve;

[0007] Analyze each time range in turn, and for any dimensional data curve, obtain the degree of data fluctuation difference between each adjacent time according to the distribution characteristics of data points between different adjacent time; obtain multiple curve time periods corresponding to the multi-dimensional data curve according to the degree of data fluctuation difference between different adjacent time periods on the water temperature curve; obtain the degree of ultrafiltration membrane pollution in each curve time period according to the distribution characteristics of data points in each curve time period of different dimensional data curves;

[0008] According to the degree of ultrafiltration membrane contamination in the real-time curve period, it is judged whether to perform backwashing at the real-time moment; if it is judged to perform backwashing, the flushing increase intensity of the real-time backwashing is obtained according to the degree of ultrafiltration membrane contamination in the curve period corresponding to the real-time backwashing, the degree of ultrafiltration membrane contamination in the adjacent curve period corresponding to the previous backwashing, and the time distance between the real-time backwashing and the previous backwashing; according to the flushing increase intensity of all backwashing within the real-time time range and the initial flushing intensity, the flushing intensity of the real-time backwashing is obtained;

[0009] According to the flushing intensity of the real-time backwashing and the time interval between the real-time backwashing and the previous backwashing, it is judged whether to perform chemical flushing at the real time; and the flushing of the ultrafiltration membrane at the real time is controlled according to the judgment result.

[0010] Furthermore, the method for obtaining the degree of data fluctuation difference includes:

[0011] For any dimensional data curve, the tangent slope at each moment on the dimensional data curve is obtained, and the difference between the tangent slope at each moment and the next adjacent moment is obtained as the slope difference;

[0012] Obtain the ratio of the corresponding data between each moment and the next adjacent moment on the dimensional data curve as the first ratio; calculate the difference between the positive integer 1 and the first ratio as the data difference;

[0013] The slope difference and data difference between each moment and the next adjacent moment are fused and normalized as the data fluctuation difference between each moment and the next adjacent moment.

[0014] Furthermore, the method for obtaining the curve period includes:

[0015] For the water temperature curve, if the data fluctuation difference between adjacent moments is less than a preset difference threshold, the corresponding adjacent moments are regarded as similar fluctuation moments; and multiple fluctuation moment ranges consisting of continuous similar fluctuation moments on the water temperature curve are obtained;

[0016] For other moments except the fluctuation time range, each other moment is merged with the adjacent fluctuation time range according to the time sequence. If other moments are adjacent to two fluctuation time ranges, the mean of the corresponding data of each moment within the fluctuation time range is calculated as the overall data level; the difference between the data value corresponding to each other moment and the overall data level is obtained, and the one with the smallest difference result is selected to merge the corresponding fluctuation time range with other moments;

[0017] According to the combined fluctuation time range, the curves of different dimensions are equally segmented to obtain the curve time periods.

[0018] Furthermore, the method for obtaining the degree of ultrafiltration membrane contamination includes:

[0019] For any dimensional data curve, the mean of all data in each curve period is obtained as the data mean; the mean of the degree of difference of data fluctuations between all adjacent moments in each curve period is obtained as the degree mean;

[0020] According to the data mean and degree mean of data curves of different dimensions in each curve period, the degree of ultrafiltration membrane contamination in each curve period is obtained. The data mean is negatively correlated with the degree of ultrafiltration membrane contamination, and the degree mean is positively correlated with the degree of ultrafiltration membrane contamination.

[0021] Further, judging whether to perform backwashing at the real time according to the degree of ultrafiltration membrane contamination in the real-time curve period includes:

[0022] The pollution degree of the ultrafiltration membrane in all curve periods is normalized. If the pollution degree of the ultrafiltration membrane in the real-time curve period after normalization is greater than the preset pollution threshold, it is determined that backwashing is performed at the real time.

[0023] Furthermore, the method for obtaining the increased intensity of flushing includes:

[0024] Obtaining the difference between the ultrafiltration membrane contamination degree in the curve period corresponding to the real-time backwashing and the ultrafiltration membrane contamination degree in the adjacent curve period corresponding to the previous backwashing as the contamination degree difference;

[0025] The ratio of the pollution degree difference and the pollution degree of the ultrafiltration membrane in the adjacent curve period of the previous backwashing to the next backwashing is obtained as the degree ratio; the difference between the time of the real-time backwashing and the previous backwashing is obtained as the time distance; the product between the degree ratio and the time distance is calculated as the effectiveness of the previous backwashing;

[0026] The ratio of the ultrafiltration membrane contamination degree in the time period corresponding to the real-time backwashing curve to the effectiveness degree of the previous backwashing is obtained and normalized as the flushing increase intensity of the real-time backwashing.

[0027] Furthermore, the method for obtaining the flushing intensity includes:

[0028] Calculate the sum of the positive integer 1 and the flushing increase intensity of each backwashing as the flushing weight of each backwashing;

[0029] The flushing weights of all backwashes and the initial flushing intensity are multiplied to obtain the flushing intensity of the backwash.

[0030] Further, the determining whether to perform chemical flushing includes:

[0031] According to the flushing intensity of the real-time backwashing and the time distance between the real-time backwashing and the previous backwashing, the degree of need for chemical flushing is obtained;

[0032] If the degree of chemical flushing requirement is greater than a preset requirement threshold, it is determined that chemical flushing is required at the real time moment.

[0033] Furthermore, the method for obtaining the degree of chemical flushing requirement includes:

[0034] The product of the real-time backwashing intensity and the time distance is obtained and normalized as the degree of chemical flushing requirement.

[0035] Furthermore, the method for obtaining the water temperature curve, the water production rate curve and the water clarity curve includes:

[0036] After the initial flushing time range, the inlet water temperature data, inlet water flow data, produced water flow data, and produced water turbidity data of the ultrafiltration flushing system at each time range are obtained in real time;

[0037] At any moment, the ratio between the produced water flow data and the inlet water flow data is obtained as the water production rate; the produced water turbidity data is negatively correlated and mapped as water clarity;

[0038] With the time sequence as the horizontal axis, and the inlet water temperature data, water production rate and water clarity as the vertical axis, a water temperature curve, a water production rate curve and a water clarity curve are constructed.

[0039] The present invention has the following beneficial effects:

[0040] The present invention analyzes each time range in turn, and for any dimensional data curve, obtains multiple curve time periods corresponding to the multi-dimensional data curve according to the distribution characteristics of data points between different adjacent time periods, reflecting the performance changes of the ultrafiltration membrane at different times, which is helpful to more accurately analyze the degree of pollution; according to the distribution characteristics of data points in each curve time period of the different dimensional data curves, the degree of ultrafiltration membrane pollution in each curve time period is obtained, and the degree of ultrafiltration membrane pollution in different time periods can be quantified to provide data support for subsequent flushing decisions; according to the degree of ultrafiltration membrane pollution in the real-time curve time period, it is judged whether to backwash at the real time, and timely judgment on whether backwashing is needed can prevent further deterioration of pollution; if it is judged to backwash, the real-time backwashing is judged according to the real-time backwashing. The degree of ultrafiltration membrane contamination in the flushing corresponding curve period, the degree of ultrafiltration membrane contamination in the adjacent curve period corresponding to the previous backwashing, and the time distance between the real-time backwashing and the previous backwashing are used to obtain the flushing increase intensity of the real-time backwashing, and the required flushing intensity is determined more accurately to improve the cleaning effect; the flushing intensity of the real-time backwashing is obtained according to the flushing increase intensity of all backwashings within the real-time time range and the initial flushing intensity, and the real-time flushing intensity is more comprehensive and accurate; according to the flushing intensity of the real-time backwashing and the time distance between the real-time backwashing and the previous backwashing, it is judged whether to perform chemical flushing at the real-time moment, and it is more reasonable to judge when stronger chemical flushing measures need to be taken; the ultrafiltration membrane at the real-time moment is flushed and controlled. The present invention improves the effect of flushing the ultrafiltration membrane pollution by obtaining an accurate flushing time. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0042] Figure 1 The present invention provides a flowchart of a flushing control method for an ultrafiltration flushing system according to an embodiment of the present invention.

[0043] Figure 2 A flow chart of a method for obtaining the degree of data fluctuation difference provided by an embodiment of the present invention;

[0044] Figure 3 A flow chart of a method for obtaining increased flushing intensity provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of the flushing control method for an ultrafiltration flushing system proposed by the present invention, its specific implementation, structure, features and effects, in conjunction with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0046] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0047] A specific scheme of a flushing control method for an ultrafiltration flushing system provided by the present invention is described in detail below with reference to the accompanying drawings.

[0048] See also Figure 1 , which shows a flow chart of a flushing control method for an ultrafiltration flushing system provided by an embodiment of the present invention, the specific method includes:

[0049] Step S1: Real-time acquisition of a multi-dimensional data curve of the ultrafiltration flushing system at each time range after initial flushing, wherein the multi-dimensional data curve includes: a water temperature curve, a water production rate curve, and a water clarity curve.

[0050] In an embodiment of the present invention, the structure of the ultrafiltration system is that the raw water is input into the ultrafiltration module for filtration after pretreatment, and then input into the water production pool; in order to ensure the filtration performance of the ultrafiltration membrane and extend the service life, considering that the water temperature affects the viscosity and activity speed of water molecules, and thus affects the water flux of the ultrafiltration membrane, the difference in the inlet and outlet water flow rates can reflect the water production capacity of the ultrafiltration membrane, and the turbidity of the produced water can reflect the filtration effect of the ultrafiltration membrane, and it is necessary to monitor the working water temperature, inlet flow rate, produced water flow rate and produced water turbidity of the ultrafiltration system; first, a temperature sensor and a flow sensor are respectively installed at the water inlet end of the ultrafiltration system, and a flow sensor and a turbidity sensor are respectively installed at the water production end, so as to obtain in real time a multi-dimensional data curve of the ultrafiltration flushing system at each time range after the initial flushing, and the multi-dimensional data curve includes: a water temperature curve, a water production rate curve and a water clarity curve.

[0051] It should be noted that, in one embodiment of the present invention, the method for obtaining the water temperature curve, the water production rate curve and the water turbidity curve includes:

[0052] After the initial flushing, the inlet water temperature data, inlet water flow data, produced water flow data, and produced water turbidity data of the ultrafiltration flushing system at each time range are obtained in real time;

[0053] At any moment, the ratio between the produced water flow data and the inlet water flow data is obtained as the water production rate; the produced water turbidity data is negatively correlated and mapped as water clarity;

[0054] With the time sequence as the horizontal axis, and the inlet water temperature data, water production rate and water clarity as the vertical axis, a water temperature curve, a water production rate curve and a water clarity curve are constructed.

[0055] It should be noted that, considering that the ultrafiltration membrane needs to be flushed once when it is initially used, and the flushing interval is generally 30 minutes, in one embodiment of the present invention, the time range starts from 30 minutes later, and the range formed by each moment and all historical moments is obtained, and the data curve at each moment is obtained for analysis; in other embodiments of the present invention, the size of the time neighborhood range can be set according to the specific circumstances, and is not limited or elaborated here.

[0056] It should be noted that, in one embodiment of the present invention, the time interval is 1 minute; in one embodiment of the present invention, the size of the time interval is a technical means well known to those skilled in the art, and is not limited or elaborated herein.

[0057] It should be noted that in the embodiments of the present invention, in order to facilitate the subsequent data processing, the acquired data is standardized to eliminate the dimension of the data so that indicators of different units or orders of magnitude can be comprehensively analyzed and compared to ensure the accuracy of the subsequent analysis. Standardization can adopt existing methods such as Z-score standardization and maximum and minimum standardization. The specific means are technical means well known to those skilled in the art and will not be described in detail here.

[0058] Step S2: Analyze each time range in turn. For any dimensional data curve, obtain the degree of data fluctuation difference between each adjacent time according to the distribution characteristics of data points between different adjacent time; obtain multiple curve time periods corresponding to the multi-dimensional data curve according to the degree of data fluctuation difference between different adjacent time on the water temperature curve; obtain the degree of ultrafiltration membrane contamination in each curve time according to the distribution characteristics of data points in each curve time of different dimensional data curves.

[0059] Since the ultrafiltration system is affected by the ambient temperature and water flow rate during actual operation, there will be differences in the dimensional data at different times, and the corresponding data curve will have certain fluctuations. By analyzing the distribution characteristics of data points between adjacent moments, we can more intuitively understand the fluctuation changes of the data curve; for any dimensional data curve, according to the distribution characteristics of data points between different adjacent moments, the degree of data fluctuation difference between each adjacent moment can be obtained.

[0060] Preferably, in one embodiment of the present invention, the method for obtaining the degree of data fluctuation difference can be found in Figure 2 , which shows a flow chart of a method for obtaining the degree of data fluctuation difference, including:

[0061] Step S201: For any dimensional data curve, obtain the tangent slope at each moment on the dimensional data curve, and obtain the difference in the tangent slope between each moment and the next adjacent moment as the slope difference.

[0062] The tangent slope reflects the rate of change of data on the dimensional data curve at each moment, and helps us understand the changing pattern of dimensional data. Analyzing the difference in the tangent slope between each moment and the next adjacent moment helps us understand the dynamic changes of the data. The smaller the slope difference, the more consistent the data changes.

[0063] It should be noted that, in one embodiment of the present invention, the method for obtaining the tangent slope includes: obtaining the derivative of the dimensional data curve at each moment as the tangent slope.

[0064] Step S202: Obtain the ratio of the corresponding data between each moment and the next adjacent moment on the dimensional data curve as the first ratio; calculate the difference between the positive integer 1 and the first ratio as the data difference.

[0065] By observing the changing trend of the ratio, we can understand the growth or decrease rate of the data in different time periods. The larger or smaller the ratio, the greater the difference between the data and the greater the data fluctuation.

[0066] Step S203: The slope difference and data difference between each moment and the next adjacent moment are merged and normalized to serve as the data fluctuation difference degree between each moment and the next adjacent moment.

[0067] It should be noted that, in some embodiments of the present invention, the slope difference and the data difference can be fused by addition or multiplication, and the specific means are well known to those skilled in the art and will not be elaborated here.

[0068] In one embodiment of the present invention, for any dimensional data curve, the formula for the degree of data fluctuation difference is expressed as:

[0069] ;

[0070] in, Indicates Moment and The degree of data fluctuation difference between moments; Indicates the dimension data curve The slope of the tangent line at the moment; Indicates the dimension data curve The slope of the tangent line at the moment; Indicates the dimension data curve Data at the moment; Indicates the dimension data curve Data at the moment; Indicates taking the absolute value; Represents the normalization function.

[0071] In the formula for the degree of data fluctuation difference, Indicates the first Moment and The difference in the slope of the tangent line between moments. The greater the difference, the less similar the slope of the tangent line, the more inconsistent the change between moments, and the greater the degree of data fluctuation difference. Indicates the calculation of the positive integer 1 and the dimension data curve Moment and The difference in the ratio of corresponding data between moments, the greater the difference, the greater the difference in the corresponding data between moments, and the greater the degree of data fluctuation.

[0072] It should be noted that, in one embodiment of the present invention, the normalization function is minimum-maximum normalization, and the specific means are technical means well known to those skilled in the art, which will not be elaborated here.

[0073] Due to the influence of ambient temperature and water flow velocity, the water temperature at different times may be different. By analyzing the water temperature curve, we can understand the changing rules and trends of the water temperature, reflecting the dynamic changes of the water body. According to the difference in data fluctuations between different adjacent moments on the water temperature curve, we can obtain multiple curve time periods corresponding to the multi-dimensional data curve.

[0074] Preferably, in one embodiment of the present invention, the method for obtaining the curve period includes:

[0075] For the water temperature curve, if the data fluctuation difference between adjacent moments is less than a preset difference threshold, the corresponding adjacent moments are regarded as similar fluctuation moments; and multiple fluctuation moment ranges consisting of continuous similar fluctuation moments on the water temperature curve are obtained;

[0076] For other moments except the fluctuation time range, each other moment is merged with the adjacent fluctuation time range according to the time sequence. If other moments are adjacent to two fluctuation time ranges, the mean of the corresponding data of each moment within the fluctuation time range is calculated as the overall data level; the difference between the data value corresponding to each other moment and the overall data level is obtained, and the one with the smallest difference result is selected to merge the corresponding fluctuation time range with other moments;

[0077] According to the combined fluctuation time range, the curves of different dimensions are equally segmented to obtain the curve time periods.

[0078] It should be noted that, in one embodiment of the present invention, the preset difference threshold is 0.3; in other embodiments of the present invention, the size of the preset difference threshold can be set according to specific circumstances, which is not limited or elaborated here.

[0079] Due to the extended use of the ultrafiltration membrane and the influence of factors such as the impurity content of the influent and the water temperature, the pollutants on the surface of the ultrafiltration membrane will accumulate again, affecting the filtration performance of the ultrafiltration membrane and causing changes in the dimensional data at different time periods. By analyzing the distribution characteristics of the data points in each curve time period in different dimensions, the changing trend of the ultrafiltration membrane contamination degree over time can be reflected. According to the distribution characteristics of the data points in each curve time period of the data curves of different dimensions, the ultrafiltration membrane contamination degree of each curve time period can be obtained.

[0080] Preferably, in one embodiment of the present invention, the method for obtaining the degree of ultrafiltration membrane contamination includes:

[0081] For any dimensional data curve, the mean of all data in each curve period is obtained as the data mean; the mean of the degree of difference of data fluctuations between all adjacent moments in each curve period is obtained as the degree mean;

[0082] According to the data mean and degree mean of data curves of different dimensions in each curve period, the degree of ultrafiltration membrane contamination in each curve period is obtained. The data mean is negatively correlated with the degree of ultrafiltration membrane contamination, and the degree mean is positively correlated with the degree of ultrafiltration membrane contamination.

[0083] Among them, the larger the data mean, the better the data performance in each dimension, the stronger the water permeability of the ultrafiltration membrane, and the smaller the degree of ultrafiltration membrane pollution, which is a negative correlation; the smaller the degree mean, the smaller the degree of data fluctuation difference, that is, the smaller the fluctuation trend of the data, the smaller the degree of ultrafiltration membrane pollution, which is a positive correlation.

[0084] In one embodiment of the present invention, the formula for the degree of ultrafiltration membrane contamination is expressed as:

[0085] ;

[0086] in, Indicates The degree of ultrafiltration membrane contamination during each curve period; Indicates The dimensional data curve is in The data mean of all data points within a curve period; Indicates The dimensional data curve is in The mean of the degree of the difference in data fluctuations between adjacent moments within a curve period; Indicates the number of dimensional data curves.

[0087] In the formula for ultrafiltration membrane fouling, Middle Pair Add 0.01 to avoid the situation where the denominator of the formula is 0 and the formula is meaningless; Indicates the calculation of different dimensional data curves in the The cumulative value of the ratio of the data mean and the degree mean of each curve period, the larger the cumulative value of the ratio, the larger the ratio, that is, the larger the data mean, the smaller the degree mean, indicating that the larger the dimensional data of the ultrafiltration membrane, the better the filtering performance, the smaller the degree of data fluctuation difference, and the smaller the degree of ultrafiltration membrane pollution.

[0088] Step S3: Determine whether to perform backwashing at the real time according to the degree of ultrafiltration membrane contamination in the real-time curve period; if it is determined to perform backwashing, obtain the increased flushing intensity of the real-time backwashing according to the degree of ultrafiltration membrane contamination in the curve period corresponding to the real-time backwashing, the degree of ultrafiltration membrane contamination in the adjacent curve period corresponding to the previous backwashing, and the time distance between the real-time backwashing and the previous backwashing; obtain the flushing intensity of the real-time backwashing according to the increased flushing intensity of all backwashing within the real-time time range and the flushing intensity of the initial backwashing.

[0089] During operation, the ultrafiltration membrane will continuously intercept pollutants in the water, causing the membrane pollution to gradually increase. In order to obtain stable and good water quality, the more serious the pollution, the more backwashing is needed. According to the ultrafiltration membrane pollution degree during the real-time curve period, it is judged whether to backwash at real time.

[0090] Preferably, in one embodiment of the present invention, judging whether to perform backwashing at the real time according to the degree of ultrafiltration membrane contamination during the real-time curve period includes:

[0091] The pollution degree of the ultrafiltration membrane in all curve periods is normalized. If the pollution degree of the ultrafiltration membrane in the real-time curve period after normalization is greater than the preset pollution threshold, it is determined that backwashing is performed at the real time.

[0092] It should be noted that, in one embodiment of the present invention, the size of the preset pollution threshold is 0.6. In other embodiments of the present invention, the size of the preset pollution threshold is a technical means well known to those skilled in the art and is not limited or elaborated herein.

[0093] As the number of flushing times of the ultrafiltration membrane increases, the ultrafiltration membrane fiber structure may be damaged or the integrity of the membrane may be affected. As the working time increases, the accumulation of stubborn pollutants becomes more and more serious. The more serious the ultrafiltration membrane pollution is, the more the backwashing intensity required for the ultrafiltration membrane under the corresponding state should increase accordingly. If it is determined to backwash, the flushing increase intensity of the real-time backwash is obtained based on the ultrafiltration membrane pollution level in the curve period corresponding to the real-time backwash, the ultrafiltration membrane pollution level in the adjacent curve period corresponding to the previous backwash, and the time distance between the real-time backwash and the previous backwash.

[0094] Preferably, in one embodiment of the present invention, the method for obtaining the flushing increase intensity is as follows Figure 3 , which shows a flow chart of a method for obtaining flushing intensity increase, including:

[0095] Step S301: obtaining the difference between the ultrafiltration membrane contamination degree in the curve period corresponding to the real-time backwashing and the ultrafiltration membrane contamination degree in the adjacent curve period corresponding to the previous backwashing as the contamination degree difference.

[0096] As time goes by, the impact of pollutants becomes more serious. By comparing the ultrafiltration membrane pollution degree in the curve period corresponding to the real-time backwashing and the ultrafiltration membrane pollution degree in the adjacent curve period corresponding to the previous backwashing, the growth or decrease of the ultrafiltration membrane pollution between the two backwashings can be intuitively understood. The larger the difference, the greater the ultrafiltration membrane pollution degree in the curve period corresponding to the real-time backwashing is relative to the ultrafiltration membrane pollution degree corresponding to the previous backwashing, indicating that the ultrafiltration membrane pollution degree in the curve period after the previous backwashing is smaller, and the recovery effect of the ultrafiltration membrane performance is better; but the smaller the difference, the closer the ultrafiltration membrane pollution degree in the curve period corresponding to the real-time backwashing and the ultrafiltration membrane pollution degree corresponding to the previous backwashing are, indicating that the ultrafiltration membrane pollution degree in the curve period after the previous backwashing is larger, and the recovery effect of the ultrafiltration membrane performance is worse.

[0097] Step S302: obtain the ratio of the pollution degree difference and the pollution degree of the ultrafiltration membrane in the adjacent curve period corresponding to the previous backwash as the degree ratio; obtain the difference between the real-time backwashing and the previous backwashing as the time distance; calculate the product between the degree ratio and the time distance as the effectiveness of the previous backwashing.

[0098] The degree ratio is used to further quantify the ratio of the difference in pollution degree to the membrane pollution degree after the previous backwashing, which helps to more accurately evaluate the impact of backwashing on ultrafiltration membrane pollution. If the degree ratio is larger, that is, the difference in pollution degree is larger, the ultrafiltration membrane pollution degree in the adjacent curve period corresponding to the previous backwashing is smaller, the degree of recovery of ultrafiltration membrane performance by backwashing is greater, and the greater the effectiveness.

[0099] The time distance reflects the frequency of backwashing operation. The shorter the time distance, the more frequent the backwashing operation, the faster the ultrafiltration membrane pollution rate, and the lower the effectiveness; the longer the time distance, the longer the effect of the backwashing operation lasts and the greater the effectiveness.

[0100] Step S303: Obtain the ratio of the ultrafiltration membrane contamination degree in the time period corresponding to the real-time backwashing curve to the effectiveness degree of the previous backwashing, and normalize it as the flushing increase intensity of the real-time backwashing.

[0101] In one embodiment of the present invention, the formula for increasing the intensity of flushing is expressed as:

[0102] ;

[0103] ;

[0104] in, Indicates real-time backwash The flushing increases the intensity; Indicates real-time backwash The degree of ultrafiltration membrane contamination in the corresponding curve period; Indicates The effectiveness of the backwash; Indicates The degree of ultrafiltration membrane contamination in the first curve period after the first backwash; Indicates Secondary backwash and real-time backwash The difference in time between Represents the normalization function.

[0105] In the formula for flushing to increase strength, Indicates calculation of real-time backwash The degree of ultrafiltration membrane pollution during the corresponding curve period and the The ratio of the effectiveness of the backwashing, that is, the greater the ratio of the flushing intensity increase, the greater the degree of ultrafiltration membrane pollution, the smaller the effectiveness, indicating that the data is more affected by pollution, and the more it is necessary to increase the flushing intensity; Indicates the degree ratio, The greater the degree of ultrafiltration membrane contamination in the first curve period after the first backwash, the Secondary backwash and real-time backwash The smaller the difference between the times, the The smaller the degree of recovery of ultrafiltration membrane performance after backwashing, the smaller the effectiveness; the longer the time interval and the more frequent the backwashing operation, the less effective the backwashing is.

[0106] As the filtration process continues, the ultrafiltration membrane will gradually accumulate pollutants, resulting in a decrease in membrane flux and filtration efficiency. The flushing increase intensity reflects the additional flushing intensity required during the backwashing process to effectively remove pollutants on the membrane; the initial flushing intensity provides a benchmark for the subsequent backwashing process. In the subsequent backwashing process, the flushing intensity can be adjusted according to the effect of the initial flushing intensity to ensure the efficiency and effect of the backwashing. By considering all previous backwashing effects and the initial flushing intensity, the real-time required flushing intensity can be determined more accurately; the real-time backwashing flushing intensity is obtained based on the flushing increase intensity and initial flushing intensity of all backwashes within the real-time time range.

[0107] Preferably, in one embodiment of the present invention, the method for obtaining flushing intensity includes:

[0108] Calculate the sum of the positive integer 1 and the flushing increase intensity of each backwashing as the flushing weight of each backwashing;

[0109] The flushing weights of all backwashes and the initial flushing intensity are multiplied to obtain the flushing intensity of the real-time backwash.

[0110] Among them, the initial flushing intensity is the flushing intensity when the ultrafiltration flushing system is put into use, which can be obtained in advance by the implementation personnel according to the specific situation.

[0111] It should be noted that, considering that there is a maximum flushing limit intensity for backwashing, if the flushing degree of real-time backwashing is greater than the maximum flushing limit intensity, the flushing intensity of real-time backwashing shall be set to the maximum flushing limit intensity; the maximum flushing limit intensity can be obtained in advance by the implementation personnel based on relevant reference materials and will not be elaborated here.

[0112] Step S4: judging whether chemical flushing is to be performed at the real time according to the flushing intensity of the real-time backwashing and the time interval between the real-time backwashing and the previous backwashing; and controlling the flushing of the ultrafiltration membrane at the real time according to the judgment result.

[0113] Since backwashing is a physical cleaning method, it can only remove some pollutants. As time goes by, pollutants will gradually accumulate, and the effectiveness of backwashing on the ultrafiltration membrane will become less and less, and it will be more necessary to add chemical reagents for flushing.

[0114] Preferably, in one embodiment of the present invention, determining whether to perform chemical flushing includes:

[0115] According to the flushing intensity of the real-time backwashing and the time distance between the real-time backwashing and the previous backwashing, the degree of need for chemical flushing is obtained;

[0116] If the degree of chemical flushing requirement is greater than a preset requirement threshold, it is determined that chemical flushing is required at the real time moment.

[0117] It should be noted that, in one embodiment of the present invention, the preset required threshold value is 0.5; in other embodiments of the present invention, the preset required threshold value may be set according to specific circumstances, which is not limited or elaborated herein.

[0118] Preferably, in one embodiment of the present invention, the method for obtaining the degree of chemical flushing requirement includes:

[0119] The product of the real-time backwashing intensity and the time distance is obtained and normalized as the degree of chemical flushing requirement.

[0120] In one embodiment of the present invention, the formula for the degree of chemical flushing requirement is expressed as:

[0121] ;

[0122] in, Indicates real-time backwash The degree of chemical flushing required; Indicates real-time backwash Flushing intensity; Indicates real-time backwash No. The difference between the backwashing moments, i.e. the time distance; represents the logistic function.

[0123] In the formula for the degree of chemical flushing required, The function will Perform normalized mapping; Indicates calculation of real-time backwash The ratio of flushing intensity to time distance. The larger the ratio, the greater the flushing intensity and the smaller the time distance, indicating that the degree of pollution in the corresponding curve period of real-time backwashing is greater, and the more frequent the flushing times, the more serious the accumulation of pollutants, and the greater the need for chemical flushing.

[0124] It should be noted that after determining whether backwashing and chemical flushing are performed at the real time moment, the ultrafiltration membrane at the real time moment is flushed according to the judgment result, including: if it is determined at the real time that backwashing is required, and it is further determined that chemical flushing is required, the ultrafiltration membrane at the real time moment is directly chemically flushed without backwashing; after the ultrafiltration membrane at the real time moment is flushed, the data of each dimension within the next moment range is obtained in real time for flushing control analysis, and continuous monitoring and analysis helps to adjust the filtration capacity of the ultrafiltration membrane in real time to ensure safe water quality.

[0125] In summary, the present invention analyzes the distribution of data points on the multi-dimensional data curve within each time range, and obtains the degree of ultrafiltration membrane contamination in each curve period; according to the degree of ultrafiltration membrane contamination in the real-time curve period, it is judged whether to backwash at the real time, and according to the degree of ultrafiltration membrane contamination in the curve period corresponding to the real-time backwash, the degree of ultrafiltration membrane contamination in the adjacent curve period corresponding to the previous backwash, and the time distance between the real-time backwash and the previous backwash, the flushing increase intensity of the real-time backwash is obtained; combined with the initial flushing intensity, the flushing intensity of the real-time backwash is obtained, and it is judged whether chemical flushing is performed at the real time; and the ultrafiltration membrane at the real time is flushed and controlled according to the judgment result. The present invention improves the effect of flushing ultrafiltration membrane pollution by obtaining an accurate flushing time.

[0126] It should be noted that the sequence of the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0127] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

Claims

1. A flushing control method for an ultrafiltration flushing system, characterized in that: The method comprises: A temperature sensor and a flow sensor are respectively installed at the water inlet end of the ultrafiltration system, and a flow sensor and a turbidity sensor are respectively installed at the water production end, so as to obtain in real time a multi-dimensional data curve of the ultrafiltration flushing system at each time range after the initial flushing, wherein the multi-dimensional data curve includes: a water temperature curve, a water production rate curve, and a water clarity curve; The method for obtaining the water temperature curve, the water production rate curve and the water clarity curve includes: After the initial flushing, the inlet water temperature data, inlet water flow data, produced water flow data, and produced water turbidity data of the ultrafiltration flushing system at each time range are obtained in real time; At any moment, the ratio between the produced water flow data and the inlet water flow data is obtained as the water production rate; the produced water turbidity data is negatively correlated and mapped as water clarity; With the time sequence as the horizontal axis, and the inlet water temperature data, water production rate and water clarity as the vertical axis, a water temperature curve, a water production rate curve and a water clarity curve are constructed; Analyze each time range in turn, and for any dimensional data curve, obtain the degree of data fluctuation difference between each adjacent time according to the distribution characteristics of data points between different adjacent time; obtain multiple curve time periods corresponding to the multi-dimensional data curve according to the degree of data fluctuation difference between different adjacent time periods on the water temperature curve; obtain the degree of ultrafiltration membrane pollution in each curve time period according to the distribution characteristics of data points in each curve time period of different dimensional data curves; According to the degree of ultrafiltration membrane contamination in the real-time curve period, it is judged whether to perform backwashing at the real-time moment; if it is judged to perform backwashing, the flushing increase intensity of the real-time backwashing is obtained according to the degree of ultrafiltration membrane contamination in the curve period corresponding to the real-time backwashing, the degree of ultrafiltration membrane contamination in the adjacent curve period corresponding to the previous backwashing, and the time distance between the real-time backwashing and the previous backwashing; according to the flushing increase intensity of all backwashing within the real-time time range and the initial flushing intensity, the flushing intensity of the real-time backwashing is obtained; According to the flushing intensity of the real-time backwashing and the time interval between the real-time backwashing and the previous backwashing, it is judged whether to perform chemical flushing at the real time; and the flushing of the ultrafiltration membrane at the real time is controlled according to the judgment result.

2. A flushing control method for an ultrafiltration flushing system according to claim 1, characterized in that: The method for obtaining the degree of data fluctuation difference includes: For any dimensional data curve, the tangent slope at each moment on the dimensional data curve is obtained, and the difference between the tangent slope at each moment and the next adjacent moment is obtained as the slope difference; Obtain the ratio of the corresponding data between each moment and the next adjacent moment on the dimensional data curve as the first ratio; calculate the difference between the positive integer 1 and the first ratio as the data difference; The slope difference and data difference between each moment and the next adjacent moment are fused and normalized as the data fluctuation difference between each moment and the next adjacent moment.

3. A flushing control method for an ultrafiltration flushing system according to claim 1, characterized in that: The method for obtaining the curve period includes: For the water temperature curve, if the data fluctuation difference between adjacent moments is less than a preset difference threshold, the corresponding adjacent moments are regarded as similar fluctuation moments; and multiple fluctuation moment ranges consisting of continuous similar fluctuation moments on the water temperature curve are obtained; For other moments except the fluctuation time range, each other moment is merged with the adjacent fluctuation time range according to the time sequence. If other moments are adjacent to two fluctuation time ranges, the mean of the corresponding data of each moment within the fluctuation time range is calculated as the overall data level; the difference between the data value corresponding to each other moment and the overall data level is obtained, and the one with the smallest difference result is selected to merge the corresponding fluctuation time range with other moments; According to the combined fluctuation time range, the curves of different dimensions are equally segmented to obtain the curve time periods.

4. A flushing control method for an ultrafiltration flushing system according to claim 1, characterized in that: The method for obtaining the degree of ultrafiltration membrane contamination includes: For any dimensional data curve, the mean of all data in each curve period is obtained as the data mean; the mean of the degree of difference of data fluctuations between all adjacent moments in each curve period is obtained as the degree mean; According to the data mean and degree mean of data curves of different dimensions in each curve period, the degree of ultrafiltration membrane contamination in each curve period is obtained. The data mean is negatively correlated with the degree of ultrafiltration membrane contamination, and the degree mean is positively correlated with the degree of ultrafiltration membrane contamination.

5. A flushing control method for an ultrafiltration flushing system according to claim 1, characterized in that: The method of judging whether to perform backwashing at a real time moment according to the degree of ultrafiltration membrane contamination during a real-time curve period includes: The pollution degree of the ultrafiltration membrane in all curve periods is normalized. If the pollution degree of the ultrafiltration membrane in the real-time curve period after normalization is greater than the preset pollution threshold, it is determined that backwashing is performed at the real time.

6. A flushing control method for an ultrafiltration flushing system according to claim 1, characterized in that: The method for obtaining the increased intensity of flushing includes: Obtaining the difference between the ultrafiltration membrane contamination degree in the curve period corresponding to the real-time backwashing and the ultrafiltration membrane contamination degree in the adjacent curve period corresponding to the previous backwashing as the contamination degree difference; The ratio of the pollution degree difference and the pollution degree of the ultrafiltration membrane in the adjacent curve period of the previous backwashing to the next backwashing is obtained as the degree ratio; the difference between the time of the real-time backwashing and the previous backwashing is obtained as the time distance; the product between the degree ratio and the time distance is calculated as the effectiveness of the previous backwashing; The ratio of the ultrafiltration membrane contamination degree in the time period corresponding to the real-time backwashing curve to the effectiveness degree of the previous backwashing is obtained and normalized as the flushing increase intensity of the real-time backwashing.

7. A flushing control method for an ultrafiltration flushing system according to claim 1, characterized in that: The method for obtaining the flushing intensity includes: Calculate the sum of the positive integer 1 and the flushing increase intensity of each backwashing as the flushing weight of each backwashing; The flushing weights of all backwashes and the initial flushing intensity are multiplied to obtain the flushing intensity of the backwash.

8. A flushing control method for an ultrafiltration flushing system according to claim 1, characterized in that: The determining whether to perform chemical flushing at the real time comprises: According to the flushing intensity of the real-time backwashing and the time distance between the real-time backwashing and the previous backwashing, the degree of need for chemical flushing is obtained; If the degree of chemical flushing requirement is greater than a preset requirement threshold, it is determined that chemical flushing is required at the real time moment.

9. A flushing control method for an ultrafiltration flushing system according to claim 8, characterized in that: The method for obtaining the degree of chemical flushing requirement includes: The product of the real-time backwashing intensity and the time distance is obtained and normalized to be the degree of chemical flushing requirement.

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