Filter cloth backwashing system for sludge filter pressing

Abstract

The present application relates to filter cloth cleaning technology field of filter pressing, especially in kind of filter cloth backflushing system for sludge filter pressing, the present application establishes the space adjacency information of each sub-region of filter cloth through the identification module, constructs at least two sequence operation execution sets through the subsequence execution module, and carries out backflushing to the sub-region in each operation execution set according to sequence, and whether the backflushing effect of sub-region is qualified is determined according to the comparison situation of flushing distension characteristic quantity through the process monitoring module, and the sludge stripping dominant sub-region is screened in the operation execution set of unqualified backflushing effect through the screening module;The backflushing strategy of sludge stripping dominant sub-region is determined according to the number of sludge stripping dominant sub-region through the control module.Furthermore, the strategy is dynamically adjusted according to the flushing effect of each region, which reduces the influence of flushing on the service life of filter cloth, and guarantees the flushing effect.

Description

Technical Field

[0001] This invention relates to the field of filter cloth cleaning technology, and in particular to a backwashing system for filter cloth used in sludge filter pressing. Background Technology

[0002] In the sludge dewatering process, the filter cloth, as the core component for solid-liquid separation, easily adsorbs sludge particles, colloids, and other impurities on its surface. If it is not cleaned in a timely and effective manner, it will cause blockage of the filter cloth pores, significantly reducing the dewatering efficiency and even affecting the moisture content of the filter cake and the subsequent treatment effect. Backwashing is a key means of cleaning the filter cloth, achieving sludge removal by impacting the filter cloth surface with high-pressure fluid. Existing filter cloth backwashing technologies mostly adopt an overall synchronous washing mode, that is, backwashing water is sprayed onto the entire filter cloth through the outlet holes on the filter plate, and the impact force of the water flow causes the filter cloth to expand to remove sludge. However, during overall backwashing, the filter cloth is affected by the fluid pressure distribution characteristics, and the force is concentrated in the middle area, resulting in the most significant expansion effect. Long-term accumulation can easily lead to damage and shorten the life of the filter cloth in the middle area due to excessive stretching. In addition, the sludge removal in the edge area of ​​the filter cloth is not thorough due to the constraint of the filter plate frame, forming stubborn blockages, which seriously affects the backwashing effect.

[0003] For example, Chinese invention patent CN118290000A, published on July 5, 2024, discloses a backwashing system for sludge filter cloths. Addressing the issue that existing sludge filter cloth backwashing systems suffer from poor efficiency due to fine sludge particles clogging the pores of the filter cloth after prolonged use, hindering effective sludge removal, the following solution is proposed: A mounting frame with two symmetrical support frames fixedly connected to its bottom, and a filter cloth mounted on the frame. A sludge inlet is fixedly connected to the upper side of the mounting frame, located above the filter cloth. This invention utilizes a sloping flushing module to stretch and tighten the filter cloth, expanding the filter pores and effectively cleaning the clogged sludge.

[0004] The following problems still exist in the existing technology:

[0005] Existing technologies do not consider the concentrated stress in the middle area during overall backwashing of the filter cloth, which can easily lead to damage to the filter cloth in the middle area due to excessive stretching. Existing technologies cannot dynamically adjust strategies according to the rinsing effect of each area, making it difficult to balance reducing the impact of rinsing on the service life of the filter cloth and ensuring the rinsing effect. Summary of the Invention

[0006] To address this issue, the present invention provides a backwashing system for filter cloths used in sludge dewatering, which overcomes the problem that existing technologies cannot dynamically adjust strategies based on the washing effect in each area, making it difficult to balance minimizing the impact of washing on the service life of the filter cloth and ensuring the washing effect.

[0007] To achieve the above objectives, the present invention provides a filter cloth backwashing system for sludge dewatering, comprising:

[0008] The backwashing module includes a water supply pipe installed inside the filter plate and several outlet holes for exporting backwash water from the water supply pipe. Each outlet hole is also equipped with a control valve for controlling the opening and closing of the outlet hole.

[0009] The identification module is used to divide the filter cloth surface into several sub-regions and establish the spatial adjacency information of each sub-region;

[0010] The sequential execution module, which is connected to the identification module, is used to construct at least two sequences of job execution sets based on the spatial adjacency information, and to backwash the sub-regions within each job execution set according to the sequence.

[0011] The process monitoring module is connected to the backwashing module, the identification module, and the sequential execution module, respectively. It is used to determine the flushing bulging characterization of each sub-area within the same sequence of operation execution sets during the process monitoring period, and to determine whether the backwashing effect of the sub-area is qualified based on the comparison of the flushing bulging characterization.

[0012] The process monitoring module acquires the point cloud data of the filter cloth surface in each sub-region of the first sequence of operation execution set in real time during the process monitoring period, and determines the maximum value of the bulging height at each time point during the monitoring period as the washing bulging characterization quantity of that sub-region.

[0013] A screening module, which is connected to the process monitoring module, is used to screen sludge stripping visible sub-regions based on the flushing bulging characterization of each sub-region within the set of operations where the backwashing effect is unqualified.

[0014] The control module, which is connected to the screening module and the backwashing module respectively, is used to determine the backwashing strategy for the sludge stripping visible sub-regions based on the result of calculation of the number of sludge stripping visible sub-regions and the total number of sub-regions in the first sequence of operation execution sets. The backwashing strategy is to adjust the number of times the sludge stripping visible sub-regions are washed, or to control the control valves in the sludge stripping visible sub-regions and the sub-regions in the next sequence of operation execution sets to open synchronously for synchronous backwashing.

[0015] Furthermore, the identification module is used to establish spatial adjacency information for each sub-region, wherein,

[0016] The identification module divides the filter cloth surface into several sub-regions of the same shape and determines the region edge of each sub-region.

[0017] The identification module determines the overlap of the edges of any two sub-regions and marks two sub-regions whose edges do not overlap as non-adjacent sub-regions.

[0018] Furthermore, the sequential execution module is used to construct a job execution set, wherein,

[0019] The sequential execution module selects non-adjacent sub-regions to form a first sequence of job execution sets based on spatial adjacency information, and forms a second sequence of job execution sets from the sub-regions not included in the first sequence of job execution sets.

[0020] Furthermore, the process monitoring period is a preset duration starting from the opening time of the control valve in the sub-region.

[0021] Furthermore, the process monitoring module is used to determine whether the backwashing effect of each sub-area is qualified, wherein,

[0022] The process monitoring module calculates the standard deviation of the flushing and swelling characterization of all sub-regions within the first sequence of operation execution set, and compares the standard deviation with a preset standard deviation threshold.

[0023] If the standard deviation is greater than the standard deviation threshold, the process monitoring module determines that the backwashing effect of the sub-region within the first sequence of job execution sets is unqualified.

[0024] Furthermore, the screening module is used to screen for sludge stripping dominant sub-regions, wherein,

[0025] The screening module is used to calculate the difference between the backwashing swelling characterization value and the swelling reference value of each sub-region within the first sequence of operation execution set based on the judgment result that the backwashing effect of each sub-region within the first sequence of operation execution set is unqualified, and to screen the sub-regions with the difference value greater than the preset difference threshold as sludge stripping visible sub-regions.

[0026] Furthermore, the control module is used to calculate the ratio of the number of sludge stripping visible sub-regions to the total number of sub-regions within the first sequence of job execution sets.

[0027] Furthermore, the control module is used to determine the backwashing strategy for the sludge stripping of the visible sub-regions, wherein,

[0028] If the ratio is greater than or equal to a preset ratio reference value, the control module adjusts the number of flushing cycles for the sludge stripping visible sub-region.

[0029] If the ratio is less than a preset ratio reference value, the control module controls the control valves in the sludge stripping visible sub-region and the sub-region of the next sequence of operation execution set to open synchronously for backwashing.

[0030] Furthermore, the control module is used to adjust the number of flushing cycles for the sludge stripping visible sub-regions according to the ratio, and the increase in the number of flushing cycles is positively correlated with the ratio.

[0031] Furthermore, the control module controls the control valves in the sludge stripping visible sub-region and the sub-region in the second sequence of operation execution set to open synchronously, so as to perform synchronous backwashing in the sludge stripping visible sub-region and the sub-region in the second sequence of operation execution set.

[0032] Compared with existing technologies, the advantages of this invention are as follows: This invention establishes spatial adjacency information for each sub-region of the filter cloth through an identification module; constructs at least two sequence execution sets through a sequential execution module; backwashes the sub-regions within each execution set according to the sequence; determines the backwashing effect of a sub-region is qualified based on a comparison of backwashing swelling characteristics through a process monitoring module; and filters sludge-shedding visible sub-regions from the execution sets with unqualified backwashing effects through a screening module. Furthermore, the control module determines the backwashing strategy for sludge-shedding visible sub-regions based on the number of such sub-regions—either by adjusting the number of washes or by controlling the control valves in the sludge-shedding visible sub-regions to open synchronously with the sub-regions in the next sequence of execution sets for synchronous backwashing. Thus, this invention achieves dynamic adjustment of the strategy based on the washing effect of each region, reducing the impact of washing on the filter cloth's service life while ensuring the washing effect.

[0033] Furthermore, based on the established spatial adjacency information of sub-regions, this invention identifies the results of non-adjacent sub-regions. The sequential execution module prioritizes screening all sub-regions that meet the conditions to form a first sequence of operation execution sets, ensuring that no two sub-regions within this set are adjacent, thus avoiding the superposition of swelling stress in adjacent areas during synchronous rinsing and preventing local filter cloth from being damaged due to excessive stretching. Since the first sequence has screened out all non-adjacent sub-regions, although the remaining sub-regions may have adjacent relationships, they are all adjacent to the sub-regions in the first sequence. By performing backwashing on the two sequence of operation execution sets in sequence, it can be ensured that the sub-regions in the same sequence do not interfere with each other when swelling, and the backwashing of the entire surface of the filter cloth can be achieved through the complete coverage of the two sequences, ultimately achieving the goal of balancing the integrity of the filter cloth and the thoroughness of backwashing.

[0034] Furthermore, in this invention, the standard deviation of the backwashing swelling characterization of all sub-regions is calculated to correspond to the differences in the degree of swelling of each sub-region: if the standard deviation is small, it indicates that the degree of filter cloth swelling in each sub-region tends to be consistent, which means that the backwash water penetration resistance is similar, the filter cloth pore blockage is uniform, and the sludge removal effect is balanced; if the standard deviation is large, it indicates that the pore blockage in some sub-regions is severe, the backwashing effect of each sub-region is large, and it is necessary to subsequently screen the sludge removal visible sub-regions and make targeted adjustments, so as to avoid local cleaning omissions or over-rinsing damage caused by uneven swelling, and ensure the consistency and reliability of the backwashing effect.

[0035] Furthermore, this invention quantifies the degree to which each sub-region deviates from the ideal swelling state by calculating the difference between the actual backwash swelling characterization value and the reference value for each sub-region. The backwash swelling characterization value is positively correlated with the degree of sludge clogging; the larger the difference, the greater the bulging of the filter cloth in that sub-region, meaning that the sludge particles in the filter cloth pores are more severely clogged, and the worse the sludge removal effect. By comparing this difference with a preset difference threshold, sub-regions with differences greater than the threshold are selected as sludge removal explicit sub-regions, accurately identifying the core areas that need to be focused on during backwashing, avoiding filter cloth damage or resource waste caused by blind treatment, and specifically solving the problem of severe local sludge residue.

[0036] Furthermore, in this invention, the control module quantifies the proportion of areas with severe sludge residue by calculating the ratio of the number of visible sludge stripping sub-regions to the total number of sub-regions within the first sequence of operation execution sets. This ratio directly reflects the extent of the problem of poor backwashing effect. If the ratio is greater than or equal to the preset ratio reference value, it indicates that the areas with severe sludge residue are widely distributed. Adjusting the flushing frequency of the visible sludge stripping sub-regions can provide targeted and enhanced cleaning for large-scale residue areas, while reducing additional flushing of already compliant areas and protecting the filter cloth from excessive damage. If the ratio is less than the preset ratio reference value, it indicates that the areas with severe sludge residue are relatively scattered. Backwashing these visible sub-regions and the sub-regions in the next sequence of operation execution sets can be performed by simultaneously opening the control valves. This utilizes the flushing water flow of adjacent sequence sub-regions to form a synergistic impact effect, expanding the local flushing coverage and impact force, effectively stripping away stubborn sludge, and avoiding the waste of resources caused by repeatedly flushing a small number of areas. This achieves a dynamic adjustment strategy based on the flushing effect of each area, reducing the impact of flushing on the service life of the filter cloth while ensuring the flushing effect.

[0037] Furthermore, when the proportion of visible sub-regions where sludge is stripped is relatively small, it indicates that sludge residue is concentrated in only a small local area. The control module controls the corresponding control valves to open synchronously for synchronous backwashing. Synchronous backwashing in a larger area can create a more concentrated water flow impact effect, improving the uniformity and coverage of local backwashing pressure. For visible sub-regions where sludge is difficult to wash, the shearing and stripping forces of the water flow on stubborn sludge are enhanced by expanding the backwashing action surface, effectively reducing the adhesion of sludge particles embedded in the filter cloth pores and compensating for the deficiency of insufficient backwashing force. Attached Figure Description

[0038] Figure 1 This is a system block diagram of the filter cloth backwashing system for sludge depressurization according to an embodiment of the present invention;

[0039] Figure 2 This is a simplified structural diagram of the backwashing module according to an embodiment of the present invention;

[0040] Figure 3 This is a flowchart illustrating the logic of determining whether the backwashing effect of each sub-region is qualified according to an embodiment of the present invention.

[0041] Figure 4 A flowchart illustrating the logic of determining the backwashing strategy in an embodiment of the present invention;

[0042] In the diagram: 1-Filter plate, 2-Water supply pipe, 3-Outlet hole. Detailed Implementation

[0043] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0044] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0045] It should be noted that in the description of this invention, the terms "upper," "lower," "inner," "outer," etc., which indicate the direction or positional relationship, are based on the direction or positional relationship shown in the drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0046] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0047] Please see Figure 1 as well as Figure 2 As shown, Figure 1 This is a system block diagram of the filter cloth backwashing system for sludge dewatering according to an embodiment of the present invention. Figure 2 This is a simplified structural diagram of the backwashing module according to an embodiment of the present invention. The sludge filter cloth backwashing system of the present invention includes:

[0048] The backwashing module includes a water supply pipe 2 installed in the filter plate 1 and several outlet holes 3 for exporting backwash water from the water supply pipe. Each outlet hole 3 is also equipped with a control valve for controlling the opening and closing of the outlet hole.

[0049] In this invention, the pressure range of the backwash water discharged through the outlet hole is 0.5-1 MPa, preferably 0.8 MPa.

[0050] The present invention does not limit the layout path of the water supply pipe, which can be arranged in parallel along the length or width of the filter plate. The outlet hole 3 on the filter plate 1 is used to outlet the backwash water in the water supply pipe 2. 2-4 outlet holes are arranged in each sub-area.

[0051] This invention does not limit the specific structure of the control valve. The control valve can be an electromagnetic control valve, and one control valve can control the opening and closing of one outlet port.

[0052] The identification module is used to divide the filter cloth surface into several sub-regions and establish the spatial adjacency information of each sub-region;

[0053] The present invention does not limit the structure of the recognition module, which can consist of a high-definition camera and an image processor. The high-definition camera is used to photograph the surface of the filter cloth, and the image processor is used to determine the regional edges of the sub-region and determine the spatial adjacency information.

[0054] In this invention, the shape of the sub-regions on the surface of the filter cloth is rectangular, and the size of the sub-region is determined based on the arrangement of 2-4 outlet holes in each sub-region.

[0055] The sequential execution module, which is connected to the identification module, is used to construct at least two sequences of job execution sets based on the spatial adjacency information, and to backwash the sub-regions within each job execution set according to the sequence.

[0056] The process monitoring module is connected to the backwashing module, the identification module, and the sequential execution module, respectively. It is used to determine the flushing bulging characterization of each sub-area within the same sequence of operation execution sets during the process monitoring period, and to determine whether the backwashing effect of the sub-area is qualified based on the comparison of the flushing bulging characterization.

[0057] The process monitoring module acquires the point cloud data of the filter cloth surface in each sub-region of the first sequence of operation execution set in real time during the process monitoring period, and determines the maximum value of the bulging height at each time point during the monitoring period as the washing bulging characterization quantity of that sub-region.

[0058] In practice, surface point cloud data can be acquired using a high-definition camera with laser scanning capabilities, which is existing technology and will not be elaborated here.

[0059] In implementation, the preset duration of the process monitoring period can be determined by technicians based on the required amount of data to be acquired. If the preset duration of the process monitoring period is too long, it will result in too much data and affect the calculation efficiency. If the preset duration of the process monitoring period is too short, it will result in too little data and affect the data accuracy. The preset duration in this invention is in the range of [3, 8], with the interval unit being s. Preferably, the preset duration of the process monitoring period is 5s.

[0060] In practice, by collecting point cloud data of the filter cloth surface in each sub-region in real time, the three-dimensional morphological changes of the filter cloth under the action of backwashing pressure can be accurately captured, and the morphological fluctuations during the swelling process can be completely restored. Then, the maximum swelling height is extracted as the washing swelling characterization quantity. The washing swelling characterization quantity can reflect the permeability of the filter cloth during the backwashing process. As can be understood by those skilled in the art, during the filter press process, sludge particles migrate from the front to the back of the filter cloth under the pressure drive. Fine particles will be embedded deep in the pores of the filter cloth fibers. The larger the washing swelling characterization quantity, the more firmly the sludge particles are embedded in the pores of the filter cloth fibers during the backwashing process, resulting in greater resistance for the backwashing water to pass through the filter cloth, and the more obvious the swelling degree of the filter cloth.

[0061] A screening module, which is connected to the process monitoring module, is used to screen sludge stripping visible sub-regions based on the flushing bulging characterization of each sub-region within the set of operations where the backwashing effect is unqualified.

[0062] The control module, which is connected to the screening module and the backwashing module respectively, is used to determine the backwashing strategy for the sludge stripping visible sub-regions based on the result of calculation of the number of sludge stripping visible sub-regions and the total number of sub-regions in the first sequence of operation execution sets. The backwashing strategy is to adjust the number of times the sludge stripping visible sub-regions are washed, or to control the control valves in the sludge stripping visible sub-regions and the sub-regions in the next sequence of operation execution sets to open synchronously for synchronous backwashing.

[0063] This invention does not limit the specific structure of the sequential execution module, process monitoring module, screening module, and control module. They or their units can be constructed using logic components, such as field-programmable logic devices, microprocessors, or processors used in computers, which will not be elaborated here.

[0064] Specifically, the identification module is used to establish spatial adjacency information for each sub-region, wherein,

[0065] The identification module divides the filter cloth surface into several sub-regions of the same shape and determines the region edge of each sub-region.

[0066] The identification module determines the overlap of the edges of any two sub-regions and marks two sub-regions whose edges do not overlap as non-adjacent sub-regions.

[0067] In this invention, determining sub-regions on the filter cloth model using image processing algorithms and recording the vertex coordinates of the sub-region's edge, as well as determining the coordinates of any point on the region's outline, is a common technique in image processing and will not be elaborated upon here.

[0068] In this invention, the identification module divides the filter cloth surface into sub-regions and establishes spatial adjacency information based on the standard physical dimensions of the filter cloth. The identification module pre-obtains the standard size parameters of the filter cloth, constructs a filter cloth model in the computer, divides the filter cloth model into sub-regions of the same shape, and records the vertex coordinates of each sub-region.

[0069] Specifically, to address the problem that simultaneous swelling of adjacent areas during backwashing of the filter cloth can easily lead to stress superposition and localized excessive stretching and damage, this invention divides the surface of the filter cloth into several sub-regions of the same shape to ensure that the stress and swelling state of each region are controllable. The coordinate positioning technology is used to accurately record the vertex coordinates of each sub-region. If the vertices coincide, it means that there is a direct edge connection between the two sub-regions. If the vertices do not coincide, it means that the two regions are not adjacent. Thus, the superposition of swelling stress caused by simultaneous rinsing of adjacent regions is avoided.

[0070] Specifically, the sequential execution module is used to construct a set of job executions, wherein,

[0071] The sequential execution module selects non-adjacent sub-regions to form a first sequence of job execution sets based on spatial adjacency information, and forms a second sequence of job execution sets from the sub-regions not included in the first sequence of job execution sets.

[0072] For example, the sequential execution module can use a row-by-row alternating selection method to filter non-adjacent sub-regions: starting from the sub-region in the first row and first column, select odd-numbered columns to include in the first sequence of job execution sets; select all even-numbered columns of sub-regions in the second row to include in the first sequence of job execution sets; select odd-numbered columns of sub-regions in the third row to include in the first sequence of job execution sets; select even-numbered columns of sub-regions in the fourth row to include in the first sequence of job execution sets; and so on, until all sub-regions in all rows have been traversed.

[0073] In implementation, based on the established spatial adjacency information of sub-regions, the results of identifying non-adjacent sub-regions are determined. The sequential execution module prioritizes screening all sub-regions that meet the conditions to form the first sequence of operation execution sets, ensuring that no two sub-regions within this set are adjacent, avoiding the superposition of swelling stress in adjacent areas during synchronous rinsing, and preventing local filter cloth from being damaged due to excessive stretching. Since the first sequence has screened out all non-adjacent sub-regions, although the remaining sub-regions may have adjacent relationships, they are all adjacent to the sub-regions in the first sequence. By performing backwashing on the two sequence operation execution sets in sequence, it is possible to ensure that the sub-regions in the same sequence do not interfere with each other when swelling, and to achieve backwashing of the entire surface of the filter cloth through the complete coverage of the two sequences, ultimately achieving the goal of balancing the integrity of the filter cloth and the thoroughness of backwashing.

[0074] Specifically, the process monitoring period is a preset duration starting from the opening time of the control valve in the sub-region.

[0075] Specifically, please refer to Figure 3 As shown, this is a flowchart illustrating the logic of determining whether the backwashing effect of each sub-region is qualified according to an embodiment of the present invention. The process monitoring module is used to determine whether the backwashing effect of each sub-region is qualified.

[0076] The process monitoring module calculates the standard deviation of the flushing and swelling characterization of all sub-regions within the first sequence of operation execution set, and compares the standard deviation with a preset standard deviation threshold.

[0077] If the standard deviation is less than or equal to the standard deviation threshold, the process monitoring module determines that the backwashing effect of the sub-region within the first sequence of operations is qualified.

[0078] If the standard deviation is greater than the standard deviation threshold, the process monitoring module determines that the backwashing effect of the sub-region within the first sequence of job execution sets is unqualified.

[0079] In implementation, the preset standard deviation threshold is determined based on the results of preliminary tests. The average standard deviation of the flushing bulging characterization of all sub-regions within the same sequence of operations under the same pressure filtration requirements is tested and recorded in advance. Under the condition that four outlet holes are arranged in each sub-region and the backwashing pressure is 0.8 MPa, the range of the standard deviation threshold is determined to be [2, 4] based on the recorded average standard deviation, with the unit of interval being mm. Preferably, the standard deviation threshold is 3 mm.

[0080] During implementation, the standard deviation of the backwash bulging characteristic of all sub-regions is calculated to correspond to the differences in the degree of bulging in each sub-region: if the standard deviation is small, it indicates that the degree of filter cloth bulging in each sub-region tends to be consistent, which means that the backwash water penetration resistance is similar, the filter cloth pore blockage is uniform, and the sludge removal effect is balanced; if the standard deviation is large, it indicates that the pore blockage in some sub-regions is severe, the backwashing effect of each sub-region is large, and it is necessary to screen the sludge removal visible sub-regions and make targeted adjustments to avoid local cleaning omissions or over-rinsing damage caused by uneven bulging, so as to ensure the consistency and reliability of the backwashing effect.

[0081] Specifically, the screening module is used to screen for sludge stripping dominant sub-regions, wherein,

[0082] The screening module is used to calculate the difference between the backwashing swelling characterization value and the swelling reference value of each sub-region within the first sequence of operation execution set based on the judgment result that the backwashing effect of each sub-region within the first sequence of operation execution set is unqualified, and to screen the sub-regions with the difference value greater than the preset difference threshold as sludge stripping visible sub-regions.

[0083] In implementation, the bulging reference value is calculated based on historical data. The average value of the bulging characterization of all sub-regions within the same sequence of operations is calculated during several backwashing processes. The average value of the bulging characterization recorded several times is used to determine the bulging reference value. The preset difference threshold is set by those skilled in the art based on the required monitoring accuracy. The larger the preset difference threshold, the fewer the number of sludge stripping sub-regions that are selected, which may lead to the omission of sub-regions with poor sludge stripping effect. The smaller the preset difference threshold, the more the number of sludge stripping sub-regions that are selected, which may lead to the selection of sub-regions with normal sludge stripping effect. Preferably, under the condition that 4 outlet holes are arranged in each sub-region and the backwashing pressure is 0.8MPa, the bulging reference value in this invention can be 15mm and the preset difference threshold can be 5mm.

[0084] For example, the filter cloth surface is divided into 25 sub-regions in 5 rows and 5 columns. The sequential execution module selects the first sequence of operation execution sets, including the odd-numbered sub-regions selected in rows 1, 3, and 5, namely 1-1, 1-3, 1-5, 3-1, 3-3, 3-5, 5-1, 5-3, 5-5, and the even-numbered sub-regions selected in rows 2 and 4, namely 2-2, 2-4, 4-2, 4-4. The final first sequence of operation execution sets contains a total of 13 sub-regions. Each sub-region has 4 outlet holes evenly distributed. The backwashing pressure is set to 0.8MPa. The process monitoring module calculates that the standard deviation of the backwashing swelling characterization of the 25 sub-regions is 3.6mm, which is greater than the preset standard deviation threshold. Therefore, the backwashing effect is deemed unqualified, and the sludge stripping visible sub-region needs to be located by the screening module.

[0085] The filtering module calculates the difference between the actual characterization value and the bulging reference value of each of the 13 sub-regions in the first sequence based on the flushing bulging characterization value.

[0086]

[0087] After comparison, the difference values ​​of 5 sub-regions in this backwashing met the screening criteria, namely 1-3, 2-2, 3-3, 4-2 and 5-3. The screening module marked these 5 sub-regions as sludge stripping explicit sub-regions.

[0088] In implementation, the degree to which each sub-region deviates from the ideal swelling state is quantified by calculating the difference between the actual backwash swelling characteristic value and the reference value. The backwash swelling characteristic value is positively correlated with the degree of sludge clogging; the larger the difference, the greater the bulging of the filter cloth in that sub-region, meaning that the sludge particles in the filter cloth pores are more severely clogged and the sludge removal effect is worse. By comparing this difference with a preset difference threshold, sub-regions with differences greater than the threshold are screened as sludge removal explicit sub-regions, accurately identifying the core areas that need to be focused on during backwashing, avoiding filter cloth damage or resource waste caused by blind treatment, and specifically solving the problem of severe local sludge residue.

[0089] Specifically, the control module is used to calculate the ratio of the number of visible sub-regions for sludge stripping to the total number of sub-regions within the first sequence of job execution sets.

[0090] Please see Figure 4 As shown, this is a logic flowchart of determining the backwashing strategy according to an embodiment of the present invention. The control module is used to determine the backwashing strategy for stripping the sludge from the visible sub-regions.

[0091] If the ratio is greater than or equal to a preset ratio reference value, the control module adjusts the number of flushing cycles for the sludge stripping visible sub-region.

[0092] If the ratio is less than a preset ratio reference value, the control module controls the control valves in the sludge stripping visible sub-region and the sub-region of the next sequence of operation execution set to open synchronously for backwashing.

[0093] In practice, the ratio reference value can be set by those skilled in the art. In this invention, the ratio reference value ranges from [0.25, 0.3], and preferably, the ratio reference value is 0.3.

[0094] In implementation, the control module quantifies the proportion of areas with severe sludge residue by calculating the ratio of the number of visible sludge stripping sub-regions to the total number of sub-regions in the first sequence of operation execution sets. This ratio directly reflects the extent of the problem of poor backwashing effect. If the ratio is greater than or equal to the preset ratio reference value, it indicates that the areas with severe sludge residue are widely distributed. Adjusting the flushing frequency of the visible sludge stripping sub-regions can provide targeted and enhanced cleaning for large-scale residue areas, while reducing additional flushing of areas that have already met the standards, thus protecting the filter cloth from excessive damage. If the ratio is less than the preset ratio reference value, it indicates that the areas with severe sludge residue are relatively scattered. Backwashing these visible sub-regions and the sub-regions in the next sequence of operation execution sets can be performed by simultaneously opening the control valves. This utilizes the flushing water flow of adjacent sequence sub-regions to form a synergistic impact effect, expanding the local flushing coverage and impact force, effectively stripping away stubborn sludge, and avoiding the waste of resources caused by repeatedly flushing a small number of areas. This achieves a dynamic adjustment strategy based on the flushing effect of each area, reducing the impact of flushing on the service life of the filter cloth while ensuring the flushing effect.

[0095] Specifically, the control module is used to adjust the number of flushing cycles for the sludge stripping visible sub-regions according to the ratio, and the increase in the number of flushing cycles is positively correlated with the ratio.

[0096] For example, if the ratio of the number of visible sub-regions to the total number of sub-regions in the first sequence of operations is greater than or equal to 0.3 and less than 0.4, then the number of flushing cycles will increase by 2.

[0097] If the ratio of the number of visible sub-regions of sludge stripping to the total number of sub-regions in the first sequence of operations is greater than or equal to 0.4 and less than 0.5, then the number of flushing cycles will increase by 4.

[0098] When the ratio of the number of visible sub-regions of sludge stripping to the total number of sub-regions in the first sequence of operations is greater than or equal to 0.5, the number of flushing cycles will increase by 6 times. In practice, 6 times is the maximum number of cycles.

[0099] In practice, the ratio of the number of flushing cycles to the number of visible sludge sub-regions to the total number of sub-regions in the first sequence of operations is set to be positively correlated. This is because a larger ratio indicates that more sub-regions have severe pore blockage, requiring stronger flushing to effectively remove sludge particles embedded deep in the filter cloth fibers. Through multiple impacts, the adhesion between stubborn sludge and the filter cloth is gradually broken down, further improving the targeted nature of the backwashing effect.

[0100] Specifically, the control module controls the control valves in the sludge stripping visible sub-region and the sub-region in the second sequence of operation execution set to open synchronously, so as to perform synchronous backwashing in the sludge stripping visible sub-region and the sub-region in the second sequence of operation execution set.

[0101] During implementation, when the number of visible sub-regions of sludge stripping is relatively small, it indicates that the sludge residue is concentrated in only a small local area. The control module controls the corresponding control valves to open synchronously for synchronous backwashing. Synchronous backwashing of a larger area can form a more concentrated water flow impact effect, improving the uniformity and coverage of local backwashing pressure. For visible sub-regions where sludge is difficult to wash, the shearing and stripping force of the water flow on stubborn sludge is enhanced by expanding the backwashing action surface, effectively reducing the adhesion of sludge particles embedded in the filter cloth pores and compensating for the deficiency of insufficient backwashing force.

[0102] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

[0103] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A filter cloth backwashing system for sludge filter pressing, characterized by, include: The backwashing module includes a water supply pipe installed inside the filter plate and several outlet holes for exporting backwash water from the water supply pipe. Each outlet hole is also equipped with a control valve for controlling the opening and closing of the outlet hole. The identification module is used to divide the filter cloth surface into several sub-regions and establish the spatial adjacency information of each sub-region; The sequential execution module, which is connected to the identification module, is used to construct at least two sequences of job execution sets based on the spatial adjacency information, and to backwash the sub-regions within each job execution set according to the sequence. The process monitoring module is connected to the backwashing module, the identification module, and the sequential execution module, respectively. It is used to determine the flushing bulging characterization of each sub-area within the same sequence of operation execution sets during the process monitoring period, and to determine whether the backwashing effect of the sub-area is qualified based on the comparison of the flushing bulging characterization. The process monitoring module acquires the point cloud data of the filter cloth surface in each sub-region of the first sequence of operation execution set in real time during the process monitoring period, and determines the maximum value of the bulging height at each time point during the monitoring period as the washing bulging characterization quantity of that sub-region. A screening module, which is connected to the process monitoring module, is used to screen sludge stripping visible sub-regions based on the flushing bulging characterization of each sub-region within the set of operations where the backwashing effect is unqualified. The control module, which is connected to the screening module and the backwashing module respectively, is used to determine the backwashing strategy for the sludge stripping visible sub-regions based on the result of calculation of the number of sludge stripping visible sub-regions and the total number of sub-regions in the first sequence of operation execution sets. The backwashing strategy is to adjust the number of times the sludge stripping visible sub-regions are washed, or to control the control valves in the sludge stripping visible sub-regions and the sub-regions in the next sequence of operation execution sets to open synchronously for synchronous backwashing.

2. The filter cloth backwashing system for sludge filter pressing according to claim 1, characterized by The identification module is used to establish spatial adjacency information for each sub-region, wherein... The identification module divides the filter cloth surface into several sub-regions of the same shape and determines the region edge of each sub-region. The identification module determines the overlap of the edges of any two sub-regions and marks two sub-regions whose edges do not overlap as non-adjacent sub-regions.

3. The filter cloth backwashing system for sludge filter pressing according to claim 2, characterized by, The sequential execution module is used to construct a set of job executions, wherein, The sequential execution module selects non-adjacent sub-regions to form a first sequence of job execution sets based on spatial adjacency information, and forms a second sequence of job execution sets from the sub-regions not included in the first sequence of job execution sets.

4. The filter cloth backwashing system for sludge filter pressing according to claim 1, characterized by The process monitoring period is a preset duration starting from the opening time of the control valve in the sub-region.

5. The filter cloth backwashing system for sludge filter pressing according to claim 4, characterized by The process monitoring module is used to determine whether the backwashing effect of each sub-area is qualified. The process monitoring module calculates the standard deviation of the flushing and swelling characterization of all sub-regions within the first sequence of operation execution set, and compares the standard deviation with a preset standard deviation threshold. If the standard deviation is greater than the standard deviation threshold, the process monitoring module determines that the backwashing effect of the sub-region within the first sequence of job execution sets is unqualified.

6. The filter cloth backwashing system for sludge filter pressing according to claim 5, characterized by The screening module is used to screen for sludge stripping dominant sub-regions, wherein... The screening module is used to calculate the difference between the backwashing swelling characterization value and the swelling reference value of each sub-region within the first sequence of operation execution set based on the judgment result that the backwashing effect of each sub-region within the first sequence of operation execution set is unqualified, and to screen the sub-regions with the difference value greater than the preset difference threshold as sludge stripping visible sub-regions.

7. The filter cloth backwashing system for sludge filter pressing according to claim 6, characterized by The control module is used to calculate the ratio of the number of visible sub-regions for sludge stripping to the total number of sub-regions within the first sequence of job execution sets.

8. The filter cloth backwashing system for sludge filter pressing according to claim 7, characterized by The control module is used to determine the backwashing strategy for the sludge stripping of the visible sub-regions, wherein... If the ratio is greater than or equal to a preset ratio reference value, the control module adjusts the number of flushing cycles for the sludge stripping visible sub-region. If the ratio is less than a preset ratio reference value, the control module controls the control valves in the sludge stripping visible sub-region and the sub-region of the next sequence of operation execution set to open synchronously for backwashing.

9. The filter cloth backwashing system for sludge dewatering according to claim 8, characterized in that, The control module is used to adjust the number of flushing cycles for the sludge stripping visible sub-regions according to the ratio, and the increase in the number of flushing cycles is positively correlated with the ratio.

10. The filter cloth backwashing system for sludge dewatering according to claim 8, characterized in that, The control module controls the control valves in the sludge stripping visible sub-region and the sub-region in the second sequence of operation execution set to open synchronously, so as to perform synchronous backwashing in the sludge stripping visible sub-region and the sub-region in the second sequence of operation execution set.

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