Backwashing system and automatic backwashing filtering device

Abstract

The invention relates to a backwashing system and an automatic backwashing filtering device.The backwashing system comprises a first backwashing pipeline used for conveying a first backwashing medium, and the first backwashing pipeline is connected with a backwashing inlet of a filter; the second backwashing pipeline is used for conveying a second backwashing medium, and the second backwashing pipeline is connected with a backwashing inlet of the filter; the controller is used for controlling the first backwashing pipeline and the second backwashing pipeline to carry out a backwashing process, the backwashing process comprises at least one emptying process, and the emptying process comprises the step of controlling the first backwashing pipeline to input the first backwashing medium so as to empty the second backwashing medium, the first backwashing medium is in a medium relation with the working medium, and the second backwashing medium is in an interference relation with the working medium. By adopting the backwashing system disclosed by the invention, the problem that a backwashing medium interferes with a working medium in the prior art is solved.

Description

Technical Field

[0001] The present application relates to the technical field of filtering equipment, and in particular to a backwashing system and an automatic backwashing filtering device. Background Art

[0002] In the related art, after the filtration equipment has been running for a period of time, a large amount of impurities accumulate in the filter element and other structures, resulting in a decrease in the filtration capacity. The backwashing system uses the backwashing medium to reversely wash the filter element and filter screen to remove the impurities and dirt deposited on their surface. In this way, the filtration capacity of the filtration equipment can be effectively restored. The backwashing medium can be, for example, desalted water, compressed air, etc.

[0003] In some special media filtration scenarios, although inputting backwash media into the filtration equipment can play a role in removing impurities, in the subsequent filtration process, the backwash media may affect the working medium. Summary of the invention

[0004] Based on this, a backwashing system and an automatic backwashing filter device are provided to improve the problem of interference of the backwashing medium with the working medium in the prior art.

[0005] In one aspect, a backwashing system is provided, which is applied to a filtration system comprising at least one filter; the backwashing system comprises:

[0006] A first backwash pipeline, used for conveying a first backwash medium, wherein the first backwash pipeline is connected to a backwash inlet of the filter;

[0007] a second backwashing pipeline, used for conveying a second backwashing medium, wherein the second backwashing pipeline is connected to a backwashing inlet of the filter;

[0008] A controller is used to control the first backwash pipeline and the second backwash pipeline to perform a backwash process, wherein the backwash process includes at least one emptying process, and the emptying process includes controlling the first backwash pipeline to input the first backwash medium to empty the second backwash medium, wherein the first backwash medium is in a neutral relationship with the working medium, and the second backwash medium is in an interference relationship with the working medium.

[0009] In one embodiment, one of the first backwashing medium and the second backwashing medium is a gas phase medium, and the other is a liquid phase medium, and the emptying process further includes at least one alternating backwashing process.

[0010] In one embodiment, the first backwash pipeline comprises a first one-way valve and a first normally closed controlled valve, the first normally closed controlled valve is connected to the inlet of the first one-way valve, and the outlet of the first one-way valve is connected to the backwash inlet of the filter;

[0011] The second backwash pipeline comprises a second one-way valve and a second normally closed controlled valve, the second normally closed controlled valve is connected to the inlet of the second one-way valve, and the outlet of the second one-way valve is connected to the backwash inlet of the filter;

[0012] The controller connects the first normally closed controlled valve and the second normally closed controlled valve.

[0013] In one embodiment, the backwash system further comprises a sewage discharge pipe, wherein the sewage discharge pipe is connected to the backwash outlet of the filter via a backwash outlet valve;

[0014] The first backwash pipeline further includes a first normally open controlled valve, which connects the inlet of the first one-way valve and the outlet of the backwash outlet valve; the second backwash pipeline further includes a second normally open controlled valve, which connects the inlet of the second one-way valve and the outlet of the backwash outlet valve;

[0015] The controller connects the first normally open controlled valve, the second normally open controlled valve, and the backwash outlet valve.

[0016] In one embodiment, the backwashing system further comprises a pressure difference monitoring unit for monitoring the pressure loss value before and after the working medium passes through the filter;

[0017] The controller is connected to the pressure difference monitoring unit;

[0018] When the pressure loss value is greater than or equal to the upper limit of the loss, it is determined that the filter is clogged, and a clog alarm instruction is executed to perform a backwashing process;

[0019] When the pressure loss value is less than or equal to the lower limit of the loss, it is determined that the filter is damaged, and a damage alarm instruction is executed;

[0020] The upper loss limit and the lower loss limit are determined according to the inlet pressure of the filter.

[0021] In one embodiment, the backwash system further comprises a discharge monitoring unit for monitoring the physical and chemical parameters of the medium in the discharge pipeline;

[0022] The controller is connected to the emission monitoring unit, and is also used to determine the physical and chemical parameter thresholds corresponding to the current operating conditions in the emission pipeline based on the current operating conditions corresponding to the filter, and determine the faulty valve under the current operating conditions based on the comparison between the physical and chemical parameters and the physical and chemical parameter thresholds.

[0023] In one embodiment, the filtration system comprises a plurality of the filters, the filtration inlet of the filter is connected to the filtration inlet valve, the filtration outlet is connected to the filtration outlet valve, and the controller is connected to the filtration inlet valve and the filtration outlet valve;

[0024] The controller is also used to respond to a switching instruction, determine a target shutdown filter and a target enabled filter from the multiple filters, open the filter inlet valve and the filter outlet valve corresponding to the target enabled filter; close the filter inlet valve and the filter outlet valve corresponding to the target shutdown filter to complete the filter switching, and allow the filter to perform a backwash process in a closed state.

[0025] In one embodiment, the closing of the filter inlet valve and the filter outlet valve corresponding to the target closed filter; and the opening of the filter inlet valve and the filter outlet valve corresponding to the target enabled filter include:

[0026] Open the filter inlet valve corresponding to the target enabled filter, and wait for a first time delay to confirm that the filter inlet valve corresponding to the target enabled filter is fully opened:

[0027] In response to the filter inlet valve corresponding to the target enabled filter being fully opened, the filter outlet valve corresponding to the target enabled filter is opened, and a delay wait is made for a second time period to confirm that the filter outlet valve corresponding to the target enabled filter is fully opened;

[0028] In response to the filter outlet valve corresponding to the target enabled filter being fully opened, closing the filter outlet valve corresponding to the target disabled filter, and waiting for a third time period to confirm that the filter outlet valve corresponding to the target disabled filter is fully closed;

[0029] In response to the filter outlet valve corresponding to the target closed filter being closed, the filter inlet valve corresponding to the target closed filter is closed, and a fourth time delay is waited to confirm that the filter inlet valve corresponding to the target closed filter is closed.

[0030] In one embodiment, the backwash inlet of each filter is provided with a backwash inlet valve, the first backwash pipeline and the second backwash pipeline are both connected to the backwash inlet valve, and the controller is connected to the backwash inlet valve.

[0031] On the other hand, an automatic backwashing filtration device is provided, comprising at least one filter and a backwashing system.

[0032] The above-mentioned backwashing system includes a first backwashing pipeline and a second backwashing pipeline, which are respectively used to input a first backwashing medium and a second backwashing medium, wherein the first backwashing medium and the working medium are in a neutral relationship, and the second backwashing medium and the working medium are in an interference relationship. When backwashing is performed, the first backwashing medium in a neutral relationship is used to empty the second backwashing medium, thereby avoiding the interference effect of the second backwashing medium on the working medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A schematic diagram of the structure of a backwashing system in one embodiment;

[0034] Figure 2 A schematic diagram of the structure of a backwashing system in another embodiment;

[0035] Figure 3 A schematic diagram of a flow chart of judging the state of a filter based on a pressure loss value in one embodiment;

[0036] Figure 4 A schematic diagram of a process of switching filters in one embodiment;

[0037] Figure 5 A schematic diagram of a process for determining a fault state based on physical and chemical parameters in one embodiment;

[0038] Figure 6 A schematic diagram of a process for backwashing a filter in one embodiment;

[0039] Figure 7 It is a schematic diagram of the process of performing alternating backwashing process and emptying process in one embodiment.

[0040] Reference numerals:

[0041] The first backwash pipeline 100, the second backwash pipeline 200, the first one-way valve V01, the second one-way valve V02, the first normally closed controlled valve V03, the second normally closed controlled valve V04, the first backwash inlet valve V05, the second backwash inlet valve V06, the first backwash outlet valve V07, the second backwash outlet valve V08, the first normally open controlled valve V09, the second normally open controlled valve V10, the first filter inlet valve V11, the second filter inlet valve V12, the first filter outlet valve V13, the second filter outlet valve V14, the first manual valve V15, the second manual valve V16, and the third manual valve V17. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0043] The filtration system is an indispensable equipment in contemporary industrial production. The filtration system is used to filter impurities in the medium and protect subsequent equipment and stable production operation.

[0044] After long-term operation, a large amount of impurities accumulate in the filter element of the filtration system. The presence of these impurities leads to a decrease in filtration capacity and may even cause damage to the filtration equipment.

[0045] By setting up a backwash system for the filtration equipment, dirt and impurities on the surface of the filter medium can be effectively removed and its filtration capacity can be restored. Regular backwashing can reduce the clogging and damage of the filter medium by dirt, extend the service life of the filter medium, reduce the replacement frequency and cost, and protect the equipment from damage.

[0046] The backwashing process requires the use of backwashing media, such as industrial water, desalted water, compressed air, etc. However, in some special filtration scenarios, there is an interference relationship between the backwashing medium and the working medium. The backwashing medium may be introduced into the working medium, causing the working medium to be affected.

[0047] The present application provides a backwashing system, which utilizes a variety of backwashing media for backwashing, and empties the backwashing media that have an interfering relationship, thereby minimizing the impact of the backwashing media on the working medium.

[0048] In one embodiment, the backwash system is used in Figure 1 The filtration system shown includes a filter. During normal filtration, the working medium, i.e., the material to be filtered, enters from the filter inlet and flows out from the filter outlet after filtration; during backwashing, the backwashing medium enters from the backwashing inlet, flushes the inside of the filter, and flows out from the backwashing outlet carrying impurities.

[0049] The backwashing system provided in this embodiment includes a first backwashing pipeline 100, a second backwashing pipeline 200 and a controller.

[0050] The first backwashing pipeline 100 is used to transport a first backwashing medium; the second backwashing pipeline 200 is used to transport a second backwashing medium. The first backwashing pipeline 100 and the second backwashing pipeline 200 are connected to the backwashing inlet of the filter.

[0051] In actual implementation, different media are used for the first backwash medium and the second backwash medium. Backwashing with multiple media can avoid specific problems caused by a single medium. For example, some media may not be effective in treating certain impurities, while another medium may be more effective, thereby improving the stability and durability of the equipment as a whole.

[0052] In this embodiment, the first backwashing medium and the working medium are in a neutral relationship, and the second backwashing medium and the working medium are in an interfering relationship.

[0053] A neutral relationship means that there is no influence between the two or the influence is acceptable. For example, for most working media, the properties of desalted water are stable and will not affect the working medium. In this embodiment, desalted water is used as the first backwash medium.

[0054] Interference relationship means that if the two are in contact or mixed, it will bring unacceptable effects. For example, some working media need to strictly control the contact with gases such as air. When gas is used as the backwashing medium, gas residue may cause the quality of the working medium to deteriorate.

[0055] In this embodiment, automatic backwashing is achieved based on an automated control process. Specifically, a controller is deployed to control the first backwashing pipeline 100 and the second backwashing pipeline 200 to transport a backwashing medium to the filter for backwashing.

[0056] The controller may adopt various modules that can realize adjustable signals, such as various single-chip microcomputers, microcontrollers, DSPs (digital signal processors), FPGAs (Field-Programmable Gate Arrays), host computers or central processing units (CPUs). In this embodiment, the controller may adopt PLCs (Programmable Logic Controllers). Various control functions may be realized by programming the PLCs. For example, in this embodiment, the collection, processing and demodulation functions of pipeline control signals and switch arrival signals are realized.

[0057] Exemplarily, the first backwash pipeline 100 and the second backwash pipeline 200 are started and stopped by setting controllable valves. When the valve on the first backwash pipeline 100 is opened, the first backwash medium flows from the medium source (e.g., a desalted water storage device) to the filter; when the valve on the second backwash pipeline 200 is opened, the second backwash medium flows from the medium source (e.g., a compressed air storage device) to the filter. The first backwash pipeline 100 and the second backwash pipeline 200 can operate simultaneously or separately.

[0058] The backwashing process includes at least one emptying process, and the emptying process refers to removing specific substances from the filter. In this embodiment, the emptying process includes controlling the first backwashing pipeline 100 to input the first backwashing medium into the filter to empty the second backwashing medium.

[0059] During the actual implementation process, one of the first backwashing medium and the second backwashing medium is a gas phase medium and the other is a liquid phase medium. During backwashing, the gas phase medium and the liquid phase medium are used for alternating backwashing. Through the alternating impact of high-speed gas and liquid flow, the filter can be cleaned more quickly and thoroughly.

[0060] Exemplarily, desalted water is used as the first backwashing medium and compressed air is used as the second backwashing medium. The working medium needs to avoid contact with compressed air to reduce the entry of air into the working medium. During the backwashing process, desalted water and compressed air are used to alternately flush the filter. After the filtering capacity of the filter meets the requirements, the compressed air is emptied with desalted water, that is, desalted water is added to the filter. After the filling is completed, the filter is waited for to be activated again.

[0061] It is understandable that in some filtration scenarios, the working medium may need to avoid contact with the liquid medium. In this case, compressed air can be used as the first backwash medium and desalted water can be used as the second backwash medium. After the alternating backwashing is completed, the desalted water is emptied using compressed air.

[0062] The backwashing system provided in the above embodiment uses a filter to automatically complete the backwashing process, and uses two backwashing media for backwashing, avoiding specific problems when backwashing with a single medium, and uses a backwashing medium that has no effect on the working medium for emptying treatment, thereby ensuring the quality of the working medium.

[0063] The following is an example of the structure of the backwash pipeline:

[0064] like Figure 1 In the embodiment, the first backwashing pipeline 100 includes a first one-way valve V01 and a first normally closed controlled valve V03, the first normally closed controlled valve V03 is connected to the inlet of the first one-way valve V01, and the outlet of the first one-way valve V01 is connected to the backwashing inlet of the filter; the second backwashing pipeline 200 includes a second one-way valve V02 and a second normally closed controlled valve V04, the second normally closed controlled valve V04 is connected to the inlet of the second one-way valve V02, and the outlet of the second one-way valve V02 is connected to the backwashing inlet of the filter; the controller connects the first normally closed controlled valve V03 and the second normally closed controlled valve V04.

[0065] A normally closed controlled valve is a valve that is in a closed state under normal circumstances and will only open under trigger control conditions. The control method of the normally closed controlled valve is, for example, electric control or pneumatic control. In this embodiment, the normally closed controlled valve is, for example, a normally closed pneumatic ball valve with open and close position signal feedback. The controller controls the pneumatic output of the pneumatic device to control the opening of the normally closed pneumatic ball valve, and the controller also receives the feedback signal of the normally closed pneumatic ball valve. When the power is off or the controller does not output an opening signal, the normally closed controlled valve remains closed.

[0066] Using a normally closed controlled valve as the control valve for the backwash medium can effectively avoid the valve from opening accidentally, and by setting a one-way valve, it can effectively prevent the working medium from flowing back into the backwash pipeline. It is particularly suitable for filter systems that assist in the management of toxic, harmful, and corrosive working media.

[0067] In actual process, the one-way valve needs a certain reverse pressure to form a lock. If the backflow is very small, the one-way valve often loses its function. Therefore, the one-way valve cannot effectively prevent backflow. The present application also installs a normally open controlled valve on the backwash pipeline to prevent the working medium from flowing back into the backwash pipeline with a large flow rate. For example:

[0068] A sewage discharge pipe is provided, and the sewage discharge pipe is connected to the backwash outlet of the filter through a backwash outlet valve. When backwashing is performed, the backwash outlet valve is opened, and the backwash medium carrying impurities flows out through the sewage discharge pipe.

[0069] The first backwash pipeline 100 also includes a first normally open controlled valve V09, which connects the inlet of the first check valve V01 and the outlet of the backwash outlet valve; the second backwash pipeline 200 also includes a second normally open controlled valve V10, which connects the inlet of the second check valve V02 and the outlet of the backwash outlet valve.

[0070] The controller connects the first normally open controlled valve V09, the second normally open controlled valve V10 and the backwash outlet valve.

[0071] The normally open controlled valve is in the open state when there is no closing command (including power outage and gas outage). During normal backwashing, the first normally open controlled valve V09 and the second normally open controlled valve V10 remain closed, and the backwashing medium can enter the filter through the one-way valve; after the backwashing is completed, the normally open controlled valve opens. If the working medium flows back, due to the pressure difference, the backflowing working medium will enter the discharge pipe through the first normally open controlled valve V09 and the second normally open controlled valve V10, and will not enter the backwashing medium pipeline.

[0072] In one embodiment, the backwashing system determines the conditions for starting the backwashing process based on the pressure difference. The filter causes the working medium to generate pressure loss during operation. The reduced passing area indicates that the pressure loss is too large and the filter element inside the filter is clogged. The enlarged passing area and the damage of the filter element indicate that the pressure loss is too small. The backwashing system provided in this embodiment also includes a pressure difference monitoring unit for monitoring the pressure loss value before and after the working medium passes through the filter. For example:

[0073] The pressure difference monitoring unit is, for example, two pressure sensors P1 and P2 disposed at the filter inlet and the filter outlet of the filter, and the pressure loss value of the working medium passing through the filter is ΔP=P1-P2.

[0074] The controller is connected to the pressure difference monitoring unit, calculates ΔP in real time, and compares it with the threshold value P set in the program. H and P L For comparison, P H is the upper limit of loss, P L This is the lower limit of loss.

[0075] When ΔP ≥ P H When the filter is determined to be clogged, a clogging alarm instruction is executed to prompt the staff to actively perform a backwashing process, or the controller responds to the clogging alarm instruction to automatically start the backwashing process.

[0076] When ΔP≤P L When the filter is determined to be damaged, a damage alarm instruction is executed, such as prompting the staff to shut down the filter.

[0077] The normal pressure loss of different types of filters may not be the same, and the pressure loss of the same type of filters under different working conditions may not be the same. The system needs to set P according to the actual operating status during debugging. H and P L .

[0078] For the filter that has been determined in the filtration system, P H and P L According to the filter inlet pressure P1 corresponding to the determination, in the actual implementation process, through the calibration test test normal filtration state, the filter pressure loss under different inlet pressure conditions, it is recommended that different inlet pressure conditions and P H and P L The mapping relationship is obtained and stored in the storage module corresponding to the controller. During the operation of the filter, the search call is made based on the inlet pressure.

[0079] In some key locations, in order to ensure the continuity of production, multiple filters are often installed in parallel, with one part used online and the other part offline for standby or backwashing. They can be switched when needed. Currently, operators are required to indirectly judge the working status of the filter based on other parameters after the filter, such as flow rate, temperature, etc., to decide whether to switch the filter. The operation of switching the filter requires the operator to manually operate on site. After the filter is switched, the switched filter also requires the operator to manually backwash the filter to complete the preparation of the filter and bring the filter to standby status. If the operator fails to detect the abnormal working status of the filter in time or fails to switch the filter in time, it often causes production delays or product degradation. In addition, the operations of switching filters and backwashing filters on site are also accompanied by safety risks for personnel.

[0080] In one embodiment of the present application, when multiple filters are used as backup for each other, the filters are automatically switched when some of them need to be backwashed offline.

[0081] For example, Figure 2 As shown, two filters are installed in parallel: a first filter (1# filter) and a second filter (2# filter), the filter inlet of the first filter is connected to the first filter inlet valve V11, and the filter outlet is connected to the first filter outlet valve V13; the filter inlet of the second filter is connected to the second filter inlet valve V12, and the filter outlet is connected to the second filter outlet valve V14, and the controller is connected to the first filter inlet valve V11, the first filter outlet valve V13, the second filter inlet valve V12, and the second filter outlet valve V14.

[0082] The first filter inlet valve V11, the first filter outlet valve V13, the second filter inlet valve V12, and the second filter outlet valve V14 are also controlled automatic valves, such as the aforementioned normally closed pneumatic ball valves with open and closed position signal feedback.

[0083] During actual operation, the controller is also used to respond to a switching instruction, determine a target shutdown filter and a target enabled filter from the multiple filters, open the filter inlet valve and the filter outlet valve corresponding to the target enabled filter; close the filter inlet valve and the filter outlet valve corresponding to the target shutdown filter to complete the filter switching, and allow the filter to perform a backwash process in the closed state.

[0084] The switching instruction is, for example, a manual switching instruction from a staff member, or an automatic switching instruction when the aforementioned pressure loss value is too large. The controller uses the filter designated by the staff to close or the filter with too large pressure loss value as the target filter to close, and uses the filter designated by the staff to open or the filter in a standby state after backwashing as the target filter to enable. The controller enables or shuts down the filter by operating the filter inlet valve and filter outlet valve before and after the filter.

[0085] like Figure 3 As shown, an exemplary flow chart of automatic switching based on pressure loss value is provided. In this process, alarms that prevent automatic operation are provided, such as alarms for valves that are not fully opened or closed, alarms for compressed air and desalted water supply pressures that are normal, etc.

[0086] The backwash inlet of each filter is provided with a backwash inlet valve, for example, the first filter is provided with a first backwash inlet valve V05, and the second filter is provided with a second backwash inlet valve V06. The first backwash pipeline 100 and the second backwash pipeline 200 are both connected to the backwash inlet valve. The first backwash inlet valve V05 and the second backwash inlet valve V06 are connected to the controller and opened when the filter needs to be backwashed.

[0087] For example, the process of shutting down the first filter and enabling the second filter is described as follows:

[0088] ①The controller recognizes that the pressure loss of the first filter is too large and backwashing is required;

[0089] ② Control the second filter inlet valve V12 and the second filter outlet valve V14 before and after the second filter to open;

[0090] ③ Control the first filter inlet valve V11 and the first filter outlet valve V13 to close;

[0091] ④ Control the first backwash inlet valve V05 to remain open and the second backwash inlet valve V06 to remain closed to complete the filter switching;

[0092] ⑤ Control the first backwash outlet valve V07 corresponding to the first filter to open and the second backwash outlet valve V08 corresponding to the second filter to close;

[0093] ⑥ Control the backwashing medium to enter the first filter for the backwashing process.

[0094] Through the automatic control of the controller, the workload of operators is greatly reduced, their work efficiency is improved, and the risk of safety accidents is reduced.

[0095] In the filter system of toxic, harmful, corrosive and other working media, high leakage prevention requirements are required. If the valve switching sequence in the pipeline is wrong or the switch is not in place, it is very likely to cause a safety accident. In one embodiment, the valve switching sequence during the filter switching process is described:

[0096] Open the filter inlet valve corresponding to the target enabled filter, and wait for a first time delay to confirm that the filter inlet valve corresponding to the target enabled filter is fully opened:

[0097] In response to the filter inlet valve corresponding to the target enabled filter being fully opened, the filter outlet valve corresponding to the target enabled filter is opened, and a delay wait is made for a second time period to confirm that the filter outlet valve corresponding to the target enabled filter is fully opened;

[0098] In response to the filter outlet valve corresponding to the target enabled filter being fully opened, closing the filter outlet valve corresponding to the target disabled filter, and waiting for a third time period to confirm that the filter outlet valve corresponding to the target disabled filter is fully closed;

[0099] In response to the filter outlet valve corresponding to the target closed filter being closed, the filter inlet valve corresponding to the target closed filter is closed, and a fourth time delay is waited to confirm that the filter inlet valve corresponding to the target closed filter is closed.

[0100] During the actual implementation process, the first duration, the second duration, the third duration and the fourth duration are determined based on the actual operation process.

[0101] For example, Figure 4 As shown, the switching process of the first filter (filter #1) and the second filter (filter #2) is described:

[0102] First, confirm the spare filter number. If filter #1 is in standby status and filter #2 is in use status at the beginning, filter #1 will be used as the target filter to be enabled. First, open the first filter inlet valve V11 of filter #1, wait for t1 seconds, and determine whether the first filter inlet valve V11 is fully opened (according to the switch feedback signal); after fully opened, open the first filter outlet valve V13, wait for t2 seconds, and determine whether the first filter outlet valve V13 is fully opened. In this step, since the inlet valve is opened before the outlet valve, no backflow will be formed in filter #1.

[0103] After the first filter outlet valve V13 is fully opened, the second filter outlet valve V14 of the 2# filter is closed, and t3 seconds are waited to determine whether the second filter outlet valve V14 is fully closed; after being fully closed, the second filter inlet valve V12 of the 2# filter is closed, and t4 seconds are waited to determine whether the second filter inlet valve V12 is fully closed. In this step, since the outlet valve is closed before the inlet valve, no backflow will be formed in the 2# filter.

[0104] After the second filter inlet valve V12 is fully closed, the second backwash outlet valve V08 corresponding to the 2# filter is opened to discharge sewage, and then wait for t5 seconds to determine whether the second backwash outlet valve V08 is fully opened.

[0105] During the sewage discharge process, the physical and chemical parameters of the sewage pipe are tested to determine whether the valve is blocked. The specific implementation method is described below.

[0106] During the above process, if any valve is not opened or closed in place, the alarm instruction of the corresponding valve can be executed.

[0107] Similarly, if filter #2 is in standby mode and filter #1 is in use mode at the beginning, filter #2 is used as the target filter to be enabled, and filter #1 is used as the target filter to be disabled.

[0108] Switching the filter according to the valve switching sequence disclosed in the above process can effectively avoid backflow and leakage of the working medium.

[0109] The backwashing system provided in the present application also provides physical and chemical parameter detection and automatic judgment of valve abnormal status alarm functions. The backwashing system also includes a discharge monitoring unit for monitoring the physical and chemical parameters of the medium in the discharge pipeline, effectively judging the working status of the valve and the pipeline, and giving alarms and prompts for abnormal conditions.

[0110] Assuming that the valves in the filter system are well sealed, there should be no working medium flowing in the sewage pipe of the filter in the non-backwashing state; on the contrary, if there is working medium flowing, it indicates that a valve may have failed in sealing. Using this feature, combined with the distribution of working medium pressure under different working conditions, it is possible to determine which valve has failed in sealing.

[0111] The controller is also used to determine the physical and chemical parameter thresholds corresponding to the current operating conditions in the discharge pipe based on the current operating conditions corresponding to the filter, and determine the faulty valve under the current operating conditions based on the comparison between the physical and chemical parameters and the physical and chemical parameter thresholds.

[0112] The monitored physical and chemical parameters include temperature, pH, flow rate, etc. For example, a temperature sensor can be selected for high-temperature media; a pH sensor can be selected for acid-base media; a flow meter can be selected for general media, etc. The program can determine whether there is working medium flowing in the pipeline based on the value detected by the sensor.

[0113] Taking temperature monitoring as an example, a temperature sensor S1 is installed in the sewage pipe, and the controller is connected to the temperature sensor to obtain the temperature sensing value.

[0114] Assume that the current working condition is that the 1# filter is online and the 2# filter is in standby state. At this time, if the temperature sensing value S1 ≥ the temperature threshold a, it is judged that one or more of the second filter inlet valve V12, the second filter outlet valve V14, the first backwash outlet valve V07, the second backwash outlet valve V08, the first backwash inlet valve V05, and the second backwash inlet valve V06 are not tightly sealed. At this time, the system gives an alarm and prompt. The operator or maintenance personnel can easily find the valve with loose sealing according to the difference in the on-site pipeline temperature.

[0115] Assume that the current working condition is that the 1# filter switches from the online use state to the offline backwashing state, and the first backwashing outlet valve V07 is opened for draining. At this time, if S1≤a, the system determines that the first backwashing outlet valve V07 or the subsequent pipeline is blocked, and the system gives an alarm and prompt.

[0116] like Figure 4 , Figure 5 The physical and chemical parameter detection process A and the physical and chemical parameter detection process B shown, after switching from the 2# filter to the 1# filter, enter the physical and chemical parameter detection process A, open the second backwash outlet valve V08, wait t5 seconds, and make sure that the second backwash outlet valve V08 is fully opened, wait t6 seconds, and judge whether the physical and chemical parameter S1 is greater than or equal to a. If so, close the second backwash outlet valve V08 after discharging sewage, and wait t7 seconds to confirm whether it is fully closed when closing. After it is fully closed, it prompts that the filter is automatically switched, sends a signal to the back system (backwash system), changes the status of the 1# filter to the online status, the usage count of the 1# filter is +1, and sends a signal to the system that the status of the 2# filter is changed to the waiting backwash status.

[0117] After switching from filter #1 to filter #2, enter the physical and chemical parameter detection process B.

[0118] In some embodiments, a first manual valve V15, a second manual valve V16, and a third manual valve V17 are respectively provided at the inlet of the working medium, the inlet of the first backwash medium, and the inlet of the second backwash medium, to ensure that the valves can continue to be operated under special circumstances and to improve the reliability and safety of the system. For example, during pipeline maintenance or overhaul, the manual valves can be conveniently closed or adjusted to avoid affecting the normal operation of other parts.

[0119] like Figure 6As shown, a flow chart of an automatic backwashing process in an embodiment is provided. In the figure, the first normally open controlled valve V09 and the second normally open controlled valve V10 are first closed, and it is detected whether both are closed in place.

[0120] like Figure 7 As shown, an exemplary schematic diagram of the alternating backwashing process and emptying process for backwashing the 1# filter is provided. In the figure, desalted water backwashing and compressed air backwashing are performed in sequence, and can be alternated multiple times according to needs. Then, when the first backwashing outlet valve V07 is closed, desalted water is used for emptying.

[0121] It can be understood that the waiting time t1-t21 in the diagram provided in the embodiment of the present application can be determined according to actual conditions.

[0122] It should be understood that although Figures 3 to 7 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figures 3 to 7 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0123] The present application also provides an automatic backwashing filtration device, comprising at least one filter, wherein the filter is backwashed by the backwashing system of the aforementioned embodiment.

[0124] For the specific definition of the automatic backwashing filter device, please refer to the definition of the backwashing system above, which will not be repeated here.

[0125] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0126] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A backwash system, characterized in that: Applicable to a filtration system comprising at least one filter; the backwashing system comprises: A first backwashing pipeline (100) for conveying a first backwashing medium, wherein the first backwashing pipeline (100) is connected to a backwashing inlet of the filter; A second backwash pipeline (200) for conveying a second backwash medium, wherein the second backwash pipeline (200) is connected to a backwash inlet of the filter; A controller is used to control the first backwash pipeline (100) and the second backwash pipeline (200) to perform a backwash process, wherein the backwash process includes at least one emptying process, and the emptying process includes controlling the first backwash pipeline (100) to input the first backwash medium to empty the second backwash medium, wherein the first backwash medium is in a neutral relationship with the working medium, and the second backwash medium is in an interference relationship with the working medium.

2. The backwashing system according to claim 1, characterized in that: One of the first backwashing medium and the second backwashing medium is a gas phase medium, and the other is a liquid phase medium. The emptying process also includes at least one alternating backwashing process.

3. The backwashing system according to claim 1, characterized in that: The first backwash pipeline (100) comprises a first one-way valve (V01) and a first normally closed controlled valve (V03), wherein the first normally closed controlled valve (V03) is connected to the inlet of the first one-way valve (V01), and the outlet of the first one-way valve (V01) is connected to the backwash inlet of the filter; The second backwash pipeline (200) comprises a second one-way valve (V02) and a second normally closed controlled valve (V04), wherein the second normally closed controlled valve (V04) is connected to the inlet of the second one-way valve (V02), and the outlet of the second one-way valve (V02) is connected to the backwash inlet of the filter; The controller connects the first normally closed controlled valve (V03) and the second normally closed controlled valve (V04).

4. The backwashing system according to claim 1, characterized in that: The backwash system further comprises a sewage discharge pipe, wherein the sewage discharge pipe is connected to the backwash outlet of the filter via a backwash outlet valve; The first backwash pipeline (100) further comprises a first normally open controlled valve (V09), wherein the first normally open controlled valve (V09) is connected to the inlet of the first check valve (V01) and the outlet of the backwash outlet valve; the second backwash pipeline (200) further comprises a second normally open controlled valve (V10), wherein the second normally open controlled valve (V10) is connected to the inlet of the second check valve (V02) and the outlet of the backwash outlet valve; The controller connects the first normally open controlled valve ( V09 ), the second normally open controlled valve ( V10 ), and the backwash outlet valve.

5. The backwash system according to claim 1, characterized in that: The backwashing system further comprises a pressure difference monitoring unit for monitoring the pressure loss value of the working medium before and after passing through the filter; The controller is connected to the pressure difference monitoring unit; When the pressure loss value is greater than or equal to the upper limit of the loss, it is determined that the filter is clogged, and a clog alarm instruction is executed to perform a backwashing process; When the pressure loss value is less than or equal to the lower limit of the loss, it is determined that the filter is damaged, and a damage alarm instruction is executed; The upper loss limit and the lower loss limit are determined according to the inlet pressure of the filter.

6. The backwashing system according to claim 1, characterized in that: The backwash system further comprises a discharge monitoring unit for monitoring the physical and chemical parameters of the medium in the discharge pipeline; The controller is connected to the emission monitoring unit, and is also used to determine the physical and chemical parameter thresholds corresponding to the current operating conditions in the emission pipeline based on the current operating conditions corresponding to the filter, and determine the faulty valve under the current operating conditions based on the comparison between the physical and chemical parameters and the physical and chemical parameter thresholds.

7. The backwash system according to claim 1, characterized in that: The filtration system comprises a plurality of filters, wherein the filter inlet of the filter is connected to the filter inlet valve, the filter outlet is connected to the filter outlet valve, and the controller is connected to the filter inlet valve and the filter outlet valve; The controller is also used to respond to a switching instruction, determine a target shutdown filter and a target enabled filter from the multiple filters, open the filter inlet valve and the filter outlet valve corresponding to the target enabled filter; close the filter inlet valve and the filter outlet valve corresponding to the target shutdown filter to complete the filter switching, and allow the filter to perform a backwash process in a closed state.

8. The backwashing system according to claim 7, characterized in that: The closing of the filter inlet valve and the filter outlet valve corresponding to the target closed filter; and the opening of the filter inlet valve and the filter outlet valve corresponding to the target enabled filter include: Open the filter inlet valve corresponding to the target enabled filter, and wait for a first time delay to confirm that the filter inlet valve corresponding to the target enabled filter is fully opened: In response to the filter inlet valve corresponding to the target enabled filter being fully opened, the filter outlet valve corresponding to the target enabled filter is opened, and a delay wait is made for a second time period to confirm that the filter outlet valve corresponding to the target enabled filter is fully opened; In response to the filter outlet valve corresponding to the target enabled filter being fully opened, closing the filter outlet valve corresponding to the target disabled filter, and waiting for a third time period to confirm that the filter outlet valve corresponding to the target disabled filter is fully closed; In response to the filter outlet valve corresponding to the target closed filter being closed, the filter inlet valve corresponding to the target closed filter is closed, and a fourth time delay is waited to confirm that the filter inlet valve corresponding to the target closed filter is closed.

9. The backwashing system according to any one of claims 1 to 8, characterized in that: The backwash inlet of each filter is provided with a backwash inlet valve, the first backwash pipeline (100) and the second backwash pipeline (200) are both connected to the backwash inlet valve, and the controller is connected to the backwash inlet valve.

10. An automatic backwashing filter device, characterized in that: The invention comprises at least one filter and a backwashing system as claimed in any one of claims 1 to 9.

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