Muddy water concentration system, concentration method and control method thereof

Abstract

The invention discloses a muddy water concentration system, a concentration method and a control method thereof, and relates to the technical field of muddy water treatment.The system comprises a concentration tank and a membrane filtration device, the concentration tank is used for storing muddy water, the membrane filtration device is provided with a membrane water inlet, a membrane concentrated water opening and a membrane purified water opening, and the membrane water inlet is communicated with the concentration tank through a muddy water inlet pipe; the membrane water inlet is used for allowing muddy water to enter the membrane filtration device for filtration, the membrane water purification port is used for allowing part of water in the muddy water to flow out, and the membrane concentrated water port is communicated with the concentration tank through a muddy water return pipe and used for allowing the muddy water with part of water removed to flow back to the concentration tank to realize circulation. The muddy water concentration method is implemented by adopting the muddy water concentration system, and the muddy water concentration system control method is applied to the muddy water concentration system. The land use area is saved, the concentration process is rapid and efficient, and the control precision of the muddy water concentration system is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of muddy water treatment, and in particular to a muddy water concentration system, a concentration method and a control method thereof. Background Art

[0002] During the operation of a water treatment plant, the generation of sludge is inevitable. The sludge contains a large amount of water and organic matter. If it is not effectively treated, it will not only occupy a large amount of land resources, but may also pollute the surrounding environment and cause a waste of water resources. Therefore, it is necessary to treat the sludge water containing sludge.

[0003] The existing complete sludge water treatment in water treatment plants usually includes five processes: concentration, conditioning, dehydration, drying, and landfill (or incineration); among them, the sludge water generally has a moisture content of 98% to 99.9%, which is high. The subsequent dehydration process generally uses mechanical dehydration, which requires the moisture content of the sludge water to be around 97%, so the sludge water needs to be concentrated. The moisture content of the concentrated sludge water directly affects the dosage of the reagents in the conditioning process and the dehydration effect, and affects the operating stability of other subsequent processes. Therefore, sludge water concentration is a key link in the sludge treatment of water treatment plants.

[0004] At present, most areas in my country use gravity thickening tanks to concentrate sludge water, which has low operating costs and simple and convenient maintenance; however, this method also has certain disadvantages. The thickening sedimentation tank will occupy a large amount of civil engineering area, and the concentration period is long. The sludge water volume and water quality have a great impact on the concentration effect.

[0005] Therefore, it is urgent to provide a sludge water concentration method to solve the above problems existing in the prior art. Summary of the invention

[0006] The purpose of the present invention is to provide a mud water concentration system, a concentration method and a control method thereof to solve the problems existing in the above-mentioned prior art, save land use area, and make the concentration process fast and efficient.

[0007] To achieve the above object, the present invention provides the following solutions:

[0008] In a first aspect, the present invention provides a mud water concentration system, comprising a concentration tank and a membrane filtration device, wherein the concentration tank is used to store mud water, and the membrane filtration device is provided with a membrane water inlet, a membrane concentrated water inlet and a membrane clean water inlet, the membrane water inlet is connected with the concentration tank through a mud water inlet pipe, and is used for mud water to enter the membrane filtration device for filtration, the membrane clean water inlet is used for part of the water in the mud water to flow out, and the membrane concentrated water inlet is connected with the concentration tank through a mud water return pipe, and is used for mud water after part of the water is removed to flow back to the concentration tank to achieve circulation.

[0009] Optionally, the membrane filtration device is a ceramic membrane filtration device.

[0010] Optionally, a membrane water inlet pump, a membrane water inlet valve, a one-way valve, a water inlet flowmeter and a water inlet pressure transmitter are sequentially arranged on the mud water inlet pipe along the water inlet direction, and a membrane concentrated water valve is arranged on the mud water return pipe; the membrane clean water outlet is connected to a clean water tank through a clean water outlet pipe, and a water production pressure transmitter, a membrane water production valve and a water production flowmeter are sequentially arranged on the clean water outlet pipe along the water outlet direction.

[0011] Optionally, a flushing mechanism is further included, and the flushing mechanism is used to flush the ceramic membrane filtration device;

[0012] Wherein, the flushing mechanism includes an air washing mechanism, and the air washing mechanism includes an air supply device, and the air supply device is connected with the membrane water inlet of the ceramic membrane filter device through an air supply pipe, and is used to introduce compressed air into the ceramic membrane filter device to flush the ceramic membrane of the ceramic membrane filter device, and a compressed air valve and a one-way valve are sequentially arranged on the air supply pipe along the gas flow direction; the membrane concentrated water outlet of the ceramic membrane filter device is also connected to a mud discharge regulating tank through an upper discharge pipe, and is used to supply muddy water and air in the ceramic membrane filter device to enter the mud discharge regulating tank, and an upper discharge valve is arranged on the upper discharge pipe;

[0013] The flushing mechanism also includes a clean water flushing mechanism, which includes a water supply pipe, the water inlet end of the water supply pipe is connected to the clean water tank, and a membrane backwashing water inlet valve, a backwashing pump and a one-way valve are sequentially arranged on the water supply pipe along the water flow direction, the outlet end of the water supply pipe is connected to the membrane concentrated water outlet through a membrane circulation water inlet pipe, which is used to supply clean water to enter the ceramic membrane filtration device to flush the ceramic membrane, and a membrane circulation water inlet valve is arranged on the membrane circulation water inlet pipe; the membrane water inlet of the ceramic membrane filtration device is also connected to the mud discharge regulating tank through a lower discharge pipe, which is used to supply muddy water formed after cleaning the ceramic membrane into the mud discharge regulating tank, and a lower discharge valve is arranged on the lower discharge pipe;

[0014] The outlet end of the water supply pipe is also connected to the membrane water purification port through a membrane backwash pipe, so as to supply clean water to reversely enter the ceramic membrane filtration device to wash the ceramic membrane. A membrane backwash valve is provided on the membrane backwash pipe. The muddy water formed after washing the ceramic membrane is discharged through the membrane concentrated water port and the membrane water inlet, and enters the mud discharge regulating tank through the upper discharge pipe and the lower discharge pipe respectively. The membrane backwash pipe is arranged in parallel with the membrane circulation water inlet pipe.

[0015] The flushing mechanism also includes a circulating alkali washing mechanism, which includes an alkali solution storage tank, which is connected to the membrane water inlet of the ceramic membrane filtration device through an alkali solution inlet pipe, and is used to supply alkali solution to the ceramic membrane filtration device to clean the ceramic membrane. An alkali solution dosing pump, an alkali solution valve and a one-way valve are sequentially arranged on the alkali solution inlet pipe along the alkali solution flow direction; the membrane water inlet is also connected to the water supply pipe between the backwash pump and the membrane backwash water inlet valve through a liquid medicine circulation pipeline, and the membrane water purification port is also connected to the liquid medicine circulation pipeline through a liquid medicine outlet pipe, a first membrane circulation water outlet valve is arranged on the liquid medicine circulation pipeline, and a second membrane circulation water outlet valve is arranged on the liquid medicine outlet pipe, and the backwash pump can drive the alkali solution to circulate in the ceramic membrane filtration device;

[0016] The flushing mechanism also includes a circulating pickling mechanism, which includes an acid storage tank. The acid storage tank is connected to the membrane water inlet of the ceramic membrane filtration device through an acid inlet pipe, and is used to supply acid to enter the ceramic membrane filtration device to clean the ceramic membrane. An acid dosing pump, an acid valve and a one-way valve are sequentially arranged on the acid inlet pipe along the acid flow direction.

[0017] Optionally, a temperature transmitter is also provided on the liquid medicine circulation pipeline.

[0018] In a second aspect, the present invention further provides a muddy water concentration method, which is implemented using the above-mentioned muddy water concentration system, comprising the steps of:

[0019] The muddy water in the concentration tank is passed through the membrane filtration device for filtration, so that part of the water in the muddy water flows out through the membrane water purification port, and the muddy water after removing part of the water flows out through the membrane concentrated water port, and flows back to the concentration tank through the muddy water return pipe to achieve circulation;

[0020] The above cycle process is repeated until the muddy water is concentrated to a water content reaching a set value.

[0021] In a third aspect, the present invention further provides a muddy water concentration system control method, which is applied to the above-mentioned muddy water concentration system, and the muddy water concentration system control method comprises:

[0022] Obtaining a working mode selection instruction; the working mode selection instruction is a timing control mode instruction or a variable control mode instruction;

[0023] When the working mode selection instruction is a timing control mode instruction, the mud water concentration system is controlled according to the timing control principle;

[0024] When the working mode selection instruction is a variable control mode instruction, the mud water concentration system is controlled according to the variable control principle.

[0025] Optionally, the timing control principle is:

[0026] When receiving the timing control mode instruction, the backwash times N1 is initialized to 0;

[0027] Initialize the basic loop times N=0;

[0028] Sending a mud water concentration process instruction to control the mud water concentration system to be in the mud water concentration process, and obtaining the mud water concentration process duration t0, until the mud water concentration process duration t0 reaches the mud water concentration process duration threshold T0, and initializing the mud water concentration process duration t0 = 0;

[0029] Send out an air flushing process instruction to control the mud water concentration system to be in the air flushing process, and obtain the air flushing process duration t1, until the air flushing process duration t1 reaches the air flushing process duration threshold T1, and initialize the air flushing process duration t1 = 0;

[0030] A clean water flushing process instruction is issued to control the mud water concentration system to be in the clean water flushing process, and the clean water flushing process duration t2 is obtained, until the clean water flushing process duration t2 reaches the clean water flushing process duration threshold T2, and the clean water flushing process duration t2 is initialized to 0;

[0031] Increase the value of the basic cycle number N by 1;

[0032] Determine whether the value of the basic cycle number N reaches the basic cycle number threshold value, and obtain a first determination result;

[0033] If the first judgment result is no, return to the step of "issuing a mud water concentration process instruction to control the mud water concentration system to be in the mud water concentration process, and obtaining the mud water concentration process duration t0, until the mud water concentration process duration t0 reaches the mud water concentration process duration threshold T0, and initializing the mud water concentration process duration t0 = 0";

[0034] If the first judgment result is yes, a water backwash process instruction is issued to control the mud water concentration system to be in the water backwash process, and the water backwash process duration t3 is obtained, until the water backwash process duration t0 reaches the water backwash process duration threshold T3, and the water backwash process duration t3 is initialized to 0;

[0035] Increase the value of the backwash times N1 by 1;

[0036] Determine whether the value of the backwashing times N1 reaches the working cycle times NY of the cyclic chemical washing interval, and obtain a second determination result;

[0037] If the second judgment result is no, then return to step "initialize basic cycle times N = 0";

[0038] If the second judgment result is yes, a circulating chemical washing process instruction is issued to control the mud and water concentration system to be in the circulating chemical washing process, and the circulating chemical washing process duration t4 is obtained until the circulating chemical washing process duration t0 reaches the circulating chemical washing process duration threshold T4, and the circulating chemical washing process duration t4 is initialized to 0, and the step of "initializing backwash times N1 = 0" is returned.

[0039] Optionally, the variable control principle is:

[0040] When receiving the variable control mode instruction, a mud water concentration process instruction is issued to control the mud water concentration system to be in the mud water concentration process, and obtain the real-time transmembrane pressure difference P until the real-time transmembrane pressure difference P reaches the transmembrane pressure difference P1 of the gas flushing process;

[0041] Send out an air flushing process instruction to control the mud water concentration system to be in the air flushing process, and obtain the air flushing process duration t1, until the air flushing process duration t1 reaches the air flushing process duration threshold T1, and initialize the air flushing process duration t1 = 0;

[0042] A clean water flushing process instruction is issued to control the mud water concentration system to be in the clean water flushing process, and the clean water flushing process duration t2 is obtained. When the clean water flushing process duration t2 reaches the clean water flushing process duration threshold T2, the transmembrane pressure difference P' at the end of the clean water flushing process is obtained, and the clean water flushing process duration t2 is initialized to 0;

[0043] Determine whether the transmembrane pressure difference P' at the end of the clean water flushing process reaches the transmembrane pressure difference P2 during the water backwashing and chemical washing process, and obtain a third determination result;

[0044] If the third judgment result is no, then return to the step of "issuing a mud water concentration process instruction to control the mud water concentration system to be in the mud water concentration process, and obtaining the real-time transmembrane pressure difference P, until the real-time transmembrane pressure difference P reaches the transmembrane pressure difference P1 of the gas flushing process;

[0045] If the third judgment result is yes, a water backwash process instruction is issued to control the mud water concentration system to be in the water backwash process, and the water backwash process duration t3 is obtained, until the water backwash process duration t0 reaches the water backwash process duration threshold T3, the transmembrane pressure difference P" at the end of the water backwash process is obtained, and the water backwash process duration t3 is initialized to 0;

[0046] Determine whether the transmembrane pressure difference P" at the end of the water backwash process reaches the transmembrane pressure difference P2 during the water backwash and chemical washing process, and obtain a fourth determination result;

[0047] If the fourth judgment result is no, then return to the step of "issuing a mud water concentration process instruction to control the mud water concentration system to be in the mud water concentration process, and obtaining the real-time transmembrane pressure difference P, until the real-time transmembrane pressure difference P reaches the transmembrane pressure difference P1 of the gas flushing process;

[0048] If the fourth judgment result is yes, a circulating chemical washing process instruction is issued to control the mud water concentration system to be in the circulating chemical washing process, and the duration t4 of the circulating chemical washing process is obtained, until the duration t0 of the circulating chemical washing process reaches the duration threshold T4 of the circulating chemical washing process, the transmembrane pressure difference P'' at the end of the circulating chemical washing process is obtained, and the duration t4 of the circulating chemical washing process is initialized to 0;

[0049] Determine whether the transmembrane pressure difference P'' at the end of the circulating chemical washing process reaches the transmembrane pressure difference P2 during the water backwashing chemical washing process, and obtain a fifth determination result;

[0050] If the result of the fifth judgment is no, then return to the step of "issuing a mud water concentration process instruction to control the mud water concentration system to be in the mud water concentration process, and obtaining the real-time transmembrane pressure difference P, until the real-time transmembrane pressure difference P reaches the transmembrane pressure difference P1 of the gas flushing process;

[0051] If the fifth judgment result is yes, an alarm signal is issued.

[0052] Optionally, before obtaining the working mode selection instruction, it also includes: using a time optimization algorithm to optimize the duration threshold of the cleaning process; the cleaning process is one of a mud water concentration process, an air flushing process, a clean water flushing process, a water backwashing process or a circulating chemical washing process;

[0053] Use time optimization algorithm to optimize the cleaning process duration threshold, including:

[0054] Obtaining a preset working time T, a first optimization range ΔT and a first step distance Δt;

[0055] Initialize the first decision threshold

[0056] Initialization time update times k = 0;

[0057] Let the value of the time update number k increase by 1, and use the formula t(k)=T-ΔT+kΔt to determine the current cleaning time; t(k) is the cleaning time after the kth update;

[0058] Control the mud water concentration system to be in the cleaning process for the current cleaning time and obtain the transmembrane pressure difference P before cleaning s and the transmembrane pressure difference after cleaning P e ;

[0059] The current cleaning time, the transmembrane pressure difference before cleaning P s and the transmembrane pressure difference after cleaning P e Substitute into the first optimization function to obtain the first optimization function value at the kth update; the first optimization function is: Wherein, ζ1 is the first optimization function, k1 is the first weight coefficient, and k2 is the second weight coefficient;

[0060] Determine whether the time update number k reaches the first determination threshold N2, and obtain a sixth determination result;

[0061] If the sixth judgment result is no, then return to the step of "increasing the value of the time update number k by 1, and determining the current cleaning time using the formula t(k)=T-ΔT+kΔt";

[0062] If the sixth judgment result is yes, the cleaning time corresponding to the maximum first optimization function value is determined as the cleaning process duration threshold.

[0063] Optionally, before obtaining the working mode selection instruction, the method further includes: optimizing the transmembrane pressure difference by using a transmembrane pressure difference optimization algorithm;

[0064] The transmembrane pressure difference optimization algorithm is:

[0065] Get the preset cleaning transmembrane pressure difference P' s , a second optimization range ΔP and a second step distance Δp;

[0066] Initialize the second decision threshold

[0067] Initialization time update times k = 0;

[0068] Let the value of the time update number k increase by 1, and use the formula P(k)=P' s -ΔP+kΔp determines the current cleaning transmembrane pressure difference; P(k) is the cleaning transmembrane pressure difference after the kth update;

[0069] Taking the current cleaning transmembrane pressure difference as the pre-cleaning transmembrane pressure difference, determine the post-cleaning transmembrane pressure difference P when the cleaning transmembrane pressure difference of the mud water concentration system reaches the cleaning transmembrane pressure difference after the kth update. e , total time of mud water concentration process ∑T1, total cleaning time ∑T2;

[0070] Substitute the pre-cleaning transmembrane pressure difference, the total time of the mud water concentration process ∑T1 and the total cleaning time ∑T2 into the second

[0071] In the optimization function, the second optimization function value at the kth update is obtained; the second optimization function is:

[0072] Among them, ζ2 is the second optimization function, k3 is the third weight coefficient, k4 is the

[0073] Four weight coefficients;

[0074] Determine whether the time update number k reaches the second determination threshold N3, and obtain a seventh determination result;

[0075] If the seventh judgment result is no, then return to step "increase the value of the time update number k by 1, and use the formula P(k)=P' s -ΔP+kΔp determines the current cleaning transmembrane pressure difference; P(k) is the cleaning transmembrane pressure difference after the kth update";

[0076] If the seventh judgment result is yes, then the cleaning transmembrane pressure difference corresponding to the maximum second optimization function value is determined to be the optimal transmembrane pressure difference.

[0077] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0078] The present invention provides a mud water concentration system and a concentration method. By passing the mud water in a concentration tank into a membrane filtration device for filtration, part of the water in the mud water can flow out through a membrane water purification port, thereby achieving mud water concentration; the mud water after part of the water is removed flows out through a membrane concentrated water port, and flows back to the concentration tank through a mud water return pipe to achieve circulation; by repeating the above circulation process, the mud water can be concentrated to a water content reaching a set value (about 97%); on the basis of a concentration tank, the present invention utilizes a cross-flow filtration process of a membrane filtration device to concentrate high-water-content mud water, does not require a large-area concentration sedimentation tank, saves land use area, and the concentration process is fast and efficient, and does not require the addition of drugs during the concentration process, thereby reducing energy consumption and drug consumption.

[0079] The present invention also provides a mud and water concentration system control method, comprising: obtaining a working mode selection instruction; when the working mode selection instruction is a timing control mode instruction, controlling the mud and water concentration system according to the timing control principle; when the working mode selection instruction is a variable control mode instruction, controlling the mud and water concentration system according to the variable control principle; the present invention improves the control accuracy of the mud and water concentration system by designing the timing control principle and the variable control principle. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0081] Figure 1 A schematic diagram of a muddy water concentration system according to an embodiment of the present invention;

[0082] Figure 2 This is a flow chart of the timing control principle in one embodiment of the present invention;

[0083] Figure 3 This is a flow chart of the variable control principle in one embodiment of the present invention;

[0084] Figure 4 A flow chart of a time optimization algorithm in one embodiment of the present invention;

[0085] Figure 5 This is a flow chart of a transmembrane pressure difference optimization algorithm in one embodiment of the present invention.

[0086] In the figure: 1-alkali solution storage tank, 2-alkali solution dosing pump, 3-alkali solution valve, 4-check valve, 5-acid solution storage tank, 6-acid solution dosing pump, 7-acid solution valve, 8-concentration tank, 9-membrane water inlet pump, 10-membrane water inlet valve, 11-water inlet flowmeter, 12-ceramic membrane filtration device, 121-membrane water inlet, 122-membrane water purification outlet, 123-membrane concentrated water outlet, 13-membrane concentrated water valve, 14-air compressor, 15-compressed air valve, 16-water inlet pressure variable transmitter, 17-water inlet pressure connecting valve, 18-upper discharge valve, 19-lower discharge valve, 20-sludge regulating tank, 21-first membrane circulation outlet valve, 22-second membrane circulation outlet valve, 23-membrane backwash valve, 24-membrane circulation inlet valve, 25-backwash pump, 26-membrane backwash inlet valve, 27-temperature transmitter, 28-membrane water production valve, 29-water production flowmeter, 30-clean water tank, 31-water production pressure transmitter, 32-water production pressure connecting valve. DETAILED DESCRIPTION

[0087] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0088] The purpose of the present invention is to provide a mud water concentration system, a concentration method and a control method thereof to solve the problems existing in the above-mentioned prior art, save land use area, and make the concentration process fast and efficient.

[0089] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0090] In an exemplary embodiment, the present invention provides a muddy water concentration system, such as Figure 1As shown, it mainly includes a concentration tank 8 and a membrane filtration device. The concentration tank 8 is used to store muddy water. The membrane filtration device is provided with a membrane water inlet 121, a membrane concentrated water inlet 123 and a membrane clean water inlet 122. The membrane water inlet 121 is connected with the concentration tank 8 through a muddy water inlet pipe, and is used for muddy water to enter the membrane filtration device for filtration. The membrane clean water inlet 122 is used for part of the water in the muddy water to flow out. The membrane concentrated water inlet 123 is connected with the concentration tank 8 through a muddy water return pipe, and is used for the muddy water after part of the water is removed to flow back to the concentration tank 8 to realize circulation.

[0091] In this embodiment, a concentration tank 8 and a membrane filtration device are provided. The muddy water in the concentration tank 8 is passed into the membrane filtration device for filtration, so that part of the water in the muddy water can flow out through the membrane water purification port 122 to achieve muddy water concentration; and the muddy water after part of the water is removed flows out through the membrane concentrated water port 123, and flows back to the concentration tank 8 through the muddy water return pipe to achieve circulation; by repeating the above-mentioned circulation process, the muddy water can be concentrated to a water content reaching a set value (about 97%); on the basis of the concentration tank 8, this embodiment utilizes the cross-flow filtration process of the membrane filtration device to concentrate the high-water content muddy water, does not require a large-area concentration sedimentation tank, saves land use area, and the concentration process is fast and efficient, and the concentration process does not require the addition of drugs, reducing energy consumption and drug consumption.

[0092] In this embodiment, the membrane filtration device is preferably a ceramic membrane filtration device 12, or other membrane filtration devices may be selected as needed.

[0093] In this embodiment, the membrane water inlet pump 9, membrane water inlet valve 10, check valve 4, water inlet flowmeter 11 and water inlet pressure transmitter 16 are sequentially arranged on the muddy water inlet pipe along the water inlet direction; wherein, the membrane water inlet pump 9 is preferably a booster pump, which can provide power for the circulation of muddy water, the membrane water inlet valve 10 is used to control the muddy water inlet switch, the check valve 4 prevents muddy water from flowing back, the water inlet flowmeter 11 is used to detect the muddy water inlet flow, and the water inlet pressure transmitter 16 can be arranged on the muddy water inlet pipe through the water inlet pressure connecting valve 17 to detect the muddy water inlet pressure. The membrane concentrated water valve 13 is arranged on the muddy water return pipe to control the muddy water return switch after removing part of the water. The membrane water purification port 122 is connected to the clean water tank 30 through the clean water outlet pipe, which is used to transport part of the removed water to the clean water tank 30; wherein, the clean water outlet pipe is provided with a water production pressure transmitter 31, a membrane water production valve 28 and a water production flow meter 29 in sequence along the water outlet direction, the water production pressure transmitter 31 is arranged on the clean water outlet pipe through the water production pressure connecting valve 32, which is used to detect the clean water outlet pressure, the membrane water production valve 28 is used to control the switch of the clean water outlet, and the water production flow meter 29 is used to detect the clean water outlet flow.

[0094] Furthermore, it needs to be explained that the above-mentioned valves, pressure transmitters, flow meters and membrane water inlet pump 9 can be connected to the controller signal. The controller receives and processes the data detected by the pressure transmitter, flow meter, etc., and then controls the valves and pumps to work, thereby realizing automatic control and intelligent management.

[0095] In this embodiment, in order to solve the problem that muddy water easily pollutes the ceramic membrane of the ceramic membrane filtration device 12, a flushing mechanism is further provided, and the flushing mechanism is used to flush the ceramic membrane.

[0096] Specifically, the flushing mechanism may include an air washing mechanism, which includes an air supply device, which is connected to the membrane water inlet 121 of the ceramic membrane filter device 12 through an air supply pipe, and is used to pass compressed air into the ceramic membrane filter device 12 to flush the surface of the ceramic membrane of the ceramic membrane filter device 12, thereby cleaning the ceramic membrane; wherein, the air supply device can be selected according to specific work needs, preferably an air compressor 14, or a compressed gas tank, etc., can also be selected. In addition, a compressed air valve 15 and a one-way valve 4 are sequentially arranged on the air supply pipe along the gas flow direction to control the air intake switch and prevent the compressed air from flowing back; the membrane concentrated water outlet 123 of the ceramic membrane filter device 12 is also connected to a mud discharge regulating tank 20 through an upper discharge pipe, which is used to discharge the mud water and air in the ceramic membrane filter device 12 into the mud discharge regulating tank 20, and an upper discharge valve 18 is arranged on the upper discharge pipe to control the switch.

[0097] The flushing mechanism described in this embodiment may also include a clean water flushing mechanism, which includes a water supply pipe, the water inlet end of the water supply pipe is connected to the clean water tank 30, and a membrane backwashing water inlet valve 26, a backwashing pump 25 and a one-way valve 4 are sequentially arranged on the water supply pipe along the water flow direction, the backwashing pump 25 provides power for the water flow, the water supply switch is controlled by the membrane backwashing water inlet valve 26, and the water backflow is prevented by the one-way valve 4; and the outlet end of the water supply pipe is connected to the membrane concentrated water port 123 through a membrane circulation water inlet pipe, which is used to supply clean water to enter the ceramic membrane filtration device 12 to flush the ceramic membrane, and a membrane circulation water inlet valve 24 is provided on the membrane circulation water inlet pipe to control the switch; the membrane water inlet 121 of the ceramic membrane filtration device 12 is also connected to the mud discharge regulating tank 20 through a lower discharge pipe, which is used to supply muddy water formed after cleaning the ceramic membrane to enter the mud discharge regulating tank 20, and a lower discharge valve 19 is also provided on the lower discharge pipe to control the switch.

[0098] Furthermore, the outlet end of the water supply pipe is also connected to the membrane water purification port 122 through a membrane backwash pipe, so as to supply clean water to reversely enter the ceramic membrane filtration device 12 to flush the ceramic membrane. A membrane backwash valve 23 is provided on the membrane backwash pipe to control the switch; the muddy water formed after cleaning the ceramic membrane is discharged through the membrane concentrated water port 123 and the membrane water inlet 121, and enters the mud regulating tank 20 through the upper discharge pipe and the lower discharge pipe respectively; wherein the membrane backwash pipe is arranged in parallel with the membrane circulation water inlet pipe.

[0099] In this embodiment, the flushing mechanism may also include a circulating alkali washing mechanism, which includes an alkali solution storage tank 1, in which alkali solution is stored. The alkali solution storage tank 1 is connected to the membrane water inlet 121 of the ceramic membrane filtration device 12 through an alkali solution inlet pipe, and is used to supply alkali solution to enter the ceramic membrane filtration device 12 to clean the ceramic membrane; wherein, an alkali solution dosing pump 2, an alkali solution valve 3 and a one-way valve 4 are sequentially arranged on the alkali solution inlet pipe along the alkali solution flow direction, the alkali solution dosing pump 2 is used to provide power for the alkali solution flow, the alkali solution valve 3 is used to control whether the alkali solution is passed in, and the one-way valve 4 is used to prevent the alkali solution from flowing back. Furthermore, the membrane water inlet 121 is also connected to the water supply pipe between the backwash pump 25 and the membrane backwash inlet valve 26 through the liquid medicine circulation pipeline, and the membrane water purification port 122 is also connected to the liquid medicine circulation pipeline through the liquid medicine outlet pipe. A first membrane circulation outlet valve 21 is provided on the liquid medicine circulation pipeline, and a second membrane circulation outlet valve 22 is provided on the liquid medicine outlet pipe. The backwash pump 25 can drive the alkali solution to circulate in the ceramic membrane filtration device 12; specifically, driven by the backwash pump 25, the alkali solution flows out from the membrane water inlet 121, passes through the first membrane circulation outlet valve 21, the backwash pump 25, and the membrane circulation inlet valve 24, and enters the ceramic membrane from the membrane concentrated water port 123 to form a circulating flow; part of the alkali solution flows out from the membrane water purification port 122 after being filtered by the ceramic membrane, and enters the liquid medicine circulation pipeline through the second membrane circulation outlet valve 22.

[0100] In this embodiment, the flushing mechanism also includes a circulating acid washing mechanism, which is similar to the circulating alkaline washing mechanism and mainly includes an acid storage tank 5, which is used to store acid. The acid storage tank 5 is connected to the membrane water inlet 121 of the ceramic membrane filtration device 12 through an acid inlet pipe, which is used to supply acid to enter the ceramic membrane filtration device 12 to clean the ceramic membrane. An acid dosing pump 6, an acid valve 7 and a one-way valve 4 are sequentially arranged on the acid inlet pipe along the acid flow direction.

[0101] In this embodiment, a temperature transmitter 27 is also provided on the liquid medicine circulation pipeline for measuring the liquid medicine temperature during the circulating liquid medicine washing.

[0102] Furthermore, it needs to be explained that the above-mentioned various flushing mechanisms in this embodiment can be used individually or in combination, so as to realize various cleaning methods, such as clean water backwashing, combined forward flushing (air flushing + clean water flushing), combined chemical washing (clean water flushing + acid or alkali circulating chemical washing + clean water flushing), etc., which have better cleaning effects.

[0103] In another exemplary embodiment of the present invention, a muddy water concentration method is provided, which is implemented using the above-mentioned muddy water concentration system and mainly includes the following steps:

[0104] The muddy water in the concentration tank 8 is passed through the membrane filtration device for filtration, so that part of the water in the muddy water flows out through the membrane water purification port 122, and the muddy water after removing part of the water flows out through the membrane concentrated water port 123, and flows back to the concentration tank 8 through the muddy water return pipe to achieve circulation;

[0105] The above cycle process is repeated until the muddy water is concentrated to a water content reaching a set value.

[0106] Moreover, in order to solve the problem that sludge water easily pollutes the ceramic membrane, the above-mentioned multiple flushing mechanisms are also used to achieve multiple flushing methods. The specific flushing process is detailed below.

[0107] In another exemplary embodiment of the present invention, a muddy water concentration system control method is provided. The muddy water concentration system control method is applied to a muddy water concentration system. The muddy water concentration system control method includes:

[0108] Step 1: Get the working mode selection instruction. The working mode selection instruction is a timing control mode instruction or a variable control mode instruction.

[0109] Step 2: When the working mode selection instruction is the timing control mode instruction, the mud water concentration system is controlled according to the timing control principle.

[0110] Step 3: When the working mode selection instruction is the variable control mode instruction, the mud water concentration system is controlled according to the variable control principle.

[0111] The system working process is based on the "mud and water concentration process + air flushing process + clean water flushing process" as a basic working cycle, which is counted as 1 working cycle. The working mode can be divided into "timing control principle" and "variable control principle". "Timing control principle" performs membrane cleaning according to the set basic cycle times. "Variable control principle" performs membrane cleaning according to the transmembrane pressure difference.

[0112] like Figure 2 As shown, the timing control principle is:

[0113] When the timing control mode instruction is received, the backwash times N1=0 are initialized.

[0114] Initialize the basic loop number N=0.

[0115] A mud water concentration process instruction is issued to control the mud water concentration system to be in the mud water concentration process, and the mud water concentration process duration t0 is obtained, until the mud water concentration process duration t0 reaches the mud water concentration process duration threshold T0, and the mud water concentration process duration t0 is initialized to 0.

[0116] An air flushing process instruction is issued to control the mud and water concentration system to be in the air flushing process, and the air flushing process duration t1 is obtained, until the air flushing process duration t1 reaches the air flushing process duration threshold T1, and the air flushing process duration t1 is initialized to 0.

[0117] A clean water flushing process instruction is issued to control the mud water concentration system to be in the clean water flushing process, and the clean water flushing process duration t2 is obtained, until the clean water flushing process duration t2 reaches the clean water flushing process duration threshold T2, and the clean water flushing process duration t2 is initialized to 0.

[0118] Increase the value of the basic loop number N by 1.

[0119] Determine whether the value of the basic cycle number N reaches the basic cycle number threshold, and obtain the first judgment result

[0120] If the first judgment result is no, return to the step of "issuing a mud water concentration process instruction to control the mud water concentration system to be in the mud water concentration process, and obtaining the mud water concentration process duration t0, until the mud water concentration process duration t0 reaches the mud water concentration process duration threshold T0, and initialize the mud water concentration process duration t0 = 0".

[0121] If the first judgment result is yes, a water backwash process instruction is issued to control the mud water concentration system to be in the water backwash process, and the water backwash process duration t3 is obtained until the water backwash process duration t0 reaches the water backwash process duration threshold T3, and the water backwash process duration t3 is initialized to 0.

[0122] Increase the value of the backwash number N1 by 1.

[0123] It is determined whether the value of the backwashing times N1 reaches the working cycle times NY of the cyclic chemical washing interval to obtain a second determination result.

[0124] If the second judgment result is no, return to the step of "initializing the basic cycle number N=0".

[0125] If the second judgment result is yes, a circulating chemical washing process instruction is issued to control the mud and water concentration system to be in the circulating chemical washing process, and the circulating chemical washing process duration t4 is obtained until the circulating chemical washing process duration t0 reaches the circulating chemical washing process duration threshold T4, and the circulating chemical washing process duration t4 is initialized to 0, and the step of "initializing backwash times N1 = 0" is returned.

[0126] The timing control principle is:

[0127] Step 1: Set the working time of mud and water concentration process T0, the working time of air flushing process T1, the working time of clean water flushing T2, the working time of water backwashing process T3, the working time of circulating chemical washing T4, and set the working cycle number NF of water backwashing interval and the working cycle number NY of circulating chemical washing interval. The basic cycle number N=0, the backwashing number N1=0.

[0128] Step 2: Mud and water concentration process (working time T0).

[0129] Step 3: Air flushing process (working time T1).

[0130] Step 4: Rinse with clean water (working time T2).

[0131] Step 5: Calculate the basic cycle working times N=N+1.

[0132] Step 6: Determine whether N=NF?

[0133] No: →Step5.

[0134] Yes: → Water backwash process (working time T3) → N = 0, calculate the number of backwash times N1 = N1 + 1 → Step 2

[0135] Step7: Determine whether N1=NY?

[0136] No: →Step 2.

[0137] Yes: → Circulate chemical washing process (working time T4) → N1 = 0 → Step 2.

[0138] Among them, the mud water concentration process is:

[0139] The first step: open the membrane water inlet valve 10, the membrane water production valve 28 and the membrane concentrated water valve 13.

[0140] Step 2: Start the membrane water inlet pump 9, so that the sludge water enters the membrane water inlet 121 of the ceramic membrane filter device 12 from the concentration tank 8 under the action of the membrane water inlet pump 9. Under the action of pressure, part of the water flows out from the membrane water outlet 122 of the ceramic membrane filter device 12 and enters the clean water tank 30 through the membrane water production valve 28. The sludge water with some water removed flows out from the membrane concentrated water outlet 123 of the ceramic membrane filter device 12 and returns to the concentration tank through the membrane concentrated water valve 13. Through continuous circulation, the sludge water is concentrated to a water content of about 97%, and then sent to the next sludge treatment process-sludge dehydration.

[0141] Step 3: When the set concentration working time T0 is reached, or the transmembrane pressure difference is detected to be greater than P1, the membrane water inlet pump 9 is turned off and the membrane water inlet valve 10 is closed.

[0142] The gas flushing process is:

[0143] The first step: shut down the membrane water inlet pump 9, close the membrane water inlet valve 10, the membrane water production valve 28, the membrane concentrated water valve 13, and open the upper discharge valve 18.

[0144] Step 2: Open the compressed air valve 15, and the compressed air generated by the air compressor 14 enters from the membrane water inlet 121 of the ceramic membrane filter device 12. The compressed air flushes the surface of the ceramic membrane to clean the ceramic membrane; then, the water and air in the cavity flow out from the membrane concentrated water outlet 123 together, and enter the sludge regulating tank 20 through the upper discharge valve 18.

[0145] Step 3: After the set air flushing time T1, close the compressed air valve 15.

[0146] The clean water flushing process is:

[0147] Step 1: Shut down the membrane water inlet pump 9, close the membrane water inlet valve 10, membrane water production valve 28 and membrane concentrated water valve 13. Close the upper discharge valve 18 and open the lower discharge valve 19. Open the membrane circulation water inlet valve 24 and the membrane backwash water inlet valve 26.

[0148] Step 2: Start the backwash pump 25. Clean water from the clean water tank 30 passes through the membrane backwash inlet valve 26, the backwash pump 25, and the membrane circulation inlet valve 24 into the membrane concentrate water port 123 of the ceramic membrane filtration device 12, and then flows out from the membrane inlet 121, and enters the mud discharge regulating tank 20 through the lower discharge valve 19. The clean water flushes the surface of the ceramic membrane to clean the ceramic membrane.

[0149] Step 3: After the set clean water flushing time T2, turn off the backwash pump 25.

[0150] The circulating chemical washing (alkaline solution) process is:

[0151] The first step: shut down the membrane water inlet pump 9, close the membrane water inlet valve 10, membrane water production valve 28 and membrane concentrated water valve 13. Open the upper discharge valve 18, close the lower discharge valve 19, and open the alkali solution valve 3.

[0152] Step 2: Start the alkali solution dosing pump 2 , and the alkali solution flows from the alkali solution storage tank 1 through the alkali solution dosing pump 2 and the alkali solution valve 3 , and enters the ceramic membrane from the membrane water inlet 121 of the ceramic membrane filtration device 12 .

[0153] Step 3: After the alkali solution dosing pump 2 runs for a set time (the set time is determined by calculating the volume of the ceramic membrane cavity and the flow rate of the dosing pump), the alkali solution fills the ceramic membrane cavity, and the alkali solution dosing pump 2 is shut down.

[0154] Step 4: Close the upper discharge valve 18 and the alkali solution valve 3, and open the first membrane circulation water outlet valve 21, the second membrane circulation water outlet valve 22, and the membrane circulation water inlet valve 24.

[0155] Step 5: Start the backwash pump 25, the liquid medicine flows out from the membrane water inlet 121, passes through the first membrane circulation water outlet valve 21, the backwash pump 25, the membrane circulation water inlet valve 24, and enters the ceramic membrane from the membrane concentrated water outlet 123, forming a circulation flow. Part of the liquid medicine is filtered through the ceramic membrane and flows out from the membrane water outlet 122, and enters the liquid medicine circulation pipeline through the second membrane circulation water outlet valve 22.

[0156] Step 6: After the set chemical washing cycle time T4, the backwash pump 25 is turned off.

[0157] Step 7: Open the lower drain valve 19, close the first membrane circulation water outlet valve 21 and the second membrane circulation water outlet valve 22, and open the membrane backwash water inlet valve 26.

[0158] Step 8: Start the backwash pump 25, and the clean water from the clean water tank 30 passes through the membrane backwash inlet valve 26, the backwash pump 25, and the membrane circulation inlet valve 24 into the membrane concentrate outlet 123 of the ceramic membrane filtration device 12, and the liquid medicine is pressed out from the membrane inlet 121 and enters the sludge regulating tank 20 through the lower discharge valve 19.

[0159] Step 9: After the backwash pump 25 runs for a set time T5 (the set time is determined by calculating the volume of the ceramic membrane cavity and the backwash pump flow rate), the ceramic membrane cavity is filled with clean water, the chemical solution is completely discharged, and the backwash pump 25 is shut down.

[0160] The circulating chemical washing (acid solution) process is:

[0161] The acid storage tank 5, the acid dosing pump 6 and the acid valve 7 respectively replace the alkali storage tank 1, the alkali dosing pump 2 and the alkali valve 3 in the circulating chemical washing (alkali solution) process, and the rest is the same as the circulating chemical washing (alkali solution) process.

[0162] The water backwash process is:

[0163] Step 1: Shut down the membrane water inlet pump 9, close the membrane water inlet valve 10, membrane water production valve 28 and membrane concentrated water valve 13. Open the upper discharge valve 18 and lower discharge valve 19. Open the membrane backwash valve 23 and membrane backwash water inlet valve 26.

[0164] Step 2: Start the backwash pump 25. Clean water from the clean water tank 30 passes through the membrane backwash water inlet valve 26, the backwash pump 25, and the membrane backwash valve 23, enters the membrane clean water port 122 of the ceramic membrane filtration device 12, passes through the ceramic membrane in the reverse direction, flows out from the membrane water inlet 121 and the membrane concentrated water port 123, and enters the sludge regulating tank 20 through the lower discharge valve 19 and the upper discharge valve 18.

[0165] Step 3: After the set backwashing time T3 is reached, the backwashing pump 25 is turned off.

[0166] like Figure 3 As shown, the variable control principle is:

[0167] When the variable control mode instruction is received, a mud water concentration process instruction is issued to control the mud water concentration system to be in the mud water concentration process, and obtain the real-time transmembrane pressure difference P until the real-time transmembrane pressure difference P reaches the transmembrane pressure difference P1 of the gas flushing process.

[0168] An air flushing process instruction is issued to control the mud and water concentration system to be in the air flushing process, and the air flushing process duration t1 is obtained, until the air flushing process duration t1 reaches the air flushing process duration threshold T1, and the air flushing process duration t1 is initialized to 0.

[0169] A clean water flushing process instruction is issued to control the mud water concentration system to be in the clean water flushing process, and the clean water flushing process duration t2 is obtained. When the clean water flushing process duration t2 reaches the clean water flushing process duration threshold T2, the transmembrane pressure difference P' at the end of the clean water flushing process is obtained, and the clean water flushing process duration t2=0 is initialized.

[0170] It is determined whether the transmembrane pressure difference P' at the end of the clean water flushing process reaches the transmembrane pressure difference P2 during the water backwashing and chemical washing process to obtain a third determination result.

[0171] If the third judgment result is no, then return to the step of "issuing a mud water concentration process instruction to control the mud water concentration system to be in the mud water concentration process, and obtaining the real-time transmembrane pressure difference P until the real-time transmembrane pressure difference P reaches the transmembrane pressure difference P1 of the gas flushing process.

[0172] If the third judgment result is yes, a water backwash process instruction is issued to control the mud water concentration system to be in the water backwash process, and the water backwash process duration t3 is obtained. When the water backwash process duration t0 reaches the water backwash process duration threshold T3, the transmembrane pressure difference P" at the end of the water backwash process is obtained, and the water backwash process duration t3 is initialized to 0.

[0173] It is determined whether the transmembrane pressure difference P" at the end of the water backwash process reaches the transmembrane pressure difference P2 during the water backwash and chemical washing process to obtain a fourth determination result.

[0174] If the result of the fourth judgment is negative, return to the step of "issuing a muddy water concentration process instruction to control the muddy water concentration system to be in the muddy water concentration process, and obtaining the real-time transmembrane pressure difference P until the real-time transmembrane pressure difference P reaches the transmembrane pressure difference P1 for the air flushing process."

[0175] If the result of the fourth judgment is positive, issue a cyclic chemical cleaning process instruction to control the muddy water concentration system to be in the cyclic chemical cleaning process, and obtain the duration t4 of the cyclic chemical cleaning process until the duration t0 of the cyclic chemical cleaning process reaches the duration threshold T4 of the cyclic chemical cleaning process, and then obtain the transmembrane pressure difference P''' at the end of the cyclic chemical cleaning process. Initialize the duration t4 of the cyclic chemical cleaning process to 0.

[0176] Judge whether the transmembrane pressure difference P''' at the end of the cyclic chemical cleaning process reaches the transmembrane pressure difference P2 for the water backwashing chemical cleaning process, and obtain the result of the fifth judgment.

[0177] If the result of the fifth judgment is negative, return to the step of "issuing a muddy water concentration process instruction to control the muddy water concentration system to be in the muddy water concentration process, and obtaining the real-time transmembrane pressure difference P until the real-time transmembrane pressure difference P reaches the transmembrane pressure difference P1 for the air flushing process."

[0178] If the result of the fifth judgment is positive, issue an alarm signal.

[0179] Variable control method:

[0180] Step1:

[0181] Set the working time T1 for the air flushing process, the working time T2 for the clean water flushing process, the working time T3 for the water backwashing process, the working time T4 for the cyclic chemical cleaning process, and set the transmembrane pressure difference P1 for the air flushing process and the transmembrane pressure difference P2 for the water backwashing process;

[0182] Step2: Muddy water concentration process (detect the transmembrane pressure difference P, when P≥P1 → Step3).

[0183] Step3: Air flushing process (working time T2).

[0184] Step4: Clean water flushing process (working time T2).

[0185] Step5: Detect the transmembrane pressure difference P'.

[0186] When P'≥P2 → Step6).

[0187] When P'<P2 → Step2).

[0188] Step6: Water backwashing process (flushing time T3).

[0189] Step7: Detect the transmembrane pressure difference P''.

[0190] When P”≥P2 → Step8).

[0191] When P”<P2 → Step2).

[0192] Step8: Recirculating chemical cleaning process (rinsing time T4).

[0193] Step9: Detect transmembrane pressure difference P”'.

[0194] When P”'≥P2 → Step10).

[0195] When P”'<P2 → Step2).

[0196] Step10: Alarm, manual intervention, maintenance and processing.

[0197] The selection of the chemical solution in the recirculating chemical cleaning is determined according to the metal ions in the water, such as iron, manganese, as well as content, hardness and other index parameters. At the same time, a regular chemical solution change rule can be set, such as performing 1 caustic cleaning after several acid cleanings. It is also possible to change the chemical solution for chemical cleaning when the transmembrane pressure difference does not recover well (setting a recovery threshold) after chemical cleaning. The control parameter optimization adopts a local optimization method to reduce the calculation amount.

[0198] Before step 1, it also includes: adopting a time optimization algorithm to optimize the duration threshold of the cleaning process. The cleaning process is one of the mud water concentration process, air flushing process, clear water flushing process, water backwashing process or recirculating chemical cleaning process.

[0199] As Figure 4 shown, adopting a time optimization algorithm to optimize the duration threshold of the cleaning process includes:

[0200] Obtain the preset working time T, the first optimization range ΔT and the first step Δt.

[0201] Initialize the first determination threshold

[0202] Initialize the time update count k = 0.

[0203] Increase the value of the time update count k by 1, and use the formula t(k)=T - ΔT + kΔt to determine the current cleaning time t(k) as the cleaning time after the kth update.

[0204] Control the mud water concentration system to be in the cleaning process for the current cleaning time, and obtain the transmembrane pressure difference P before cleaning s and the transmembrane pressure difference P after cleaning e .

[0205] The current cleaning time, the transmembrane pressure difference P before cleaning s and the transmembrane pressure difference P after cleaning eSubstitute it into the first optimization function to get the first optimization function value at the kth update. The first optimization function is: Among them, ζ1 is the first optimization function, k1 is the first weight coefficient, and k2 is the second weight coefficient.

[0206] It is determined whether the time update number k reaches the first determination threshold N2 to obtain a sixth determination result.

[0207] If the sixth judgment result is no, return to the step of "increase the value of the time update number k by 1, and use the formula t(k)=T-ΔT+kΔt to determine the current cleaning time".

[0208] If the sixth judgment result is yes, the cleaning time corresponding to the maximum first optimization function value is determined as the cleaning process duration threshold.

[0209] Optimization of cleaning time:

[0210] Under the premise of the working time T set according to experience, the optimization range ΔT is preset, the cleaning time t is in the range of T-ΔT to T+ΔT, and the local optimal time is found with a step distance Δt. The optimization target parameter ζ is:

[0211]

[0212] Where k1 and k2 are weight coefficients, ranging from 0 to 1.

[0213] Cleaning time optimization process:

[0214] Step 1: Given the cleaning time T, optimization range ΔT, weight coefficients k1 and k2, and the first step distance Δt.

[0215] Step 2: Calculation

[0216] Step 3: Change the cleaning time: k = 1 to N2, cleaning time t(k) = T-ΔT+kΔt, obtain the transmembrane pressure difference P before cleaning s and the transmembrane pressure difference after cleaning P e , calculate the first optimization function value.

[0217] Step 4: After N2 cleaning, find the maximum value of ζ1 ζ1max and the corresponding cleaning time t(m).

[0218] ζ1max=MAX(ζ1(1), ζ1(2), ..., ζ1(N2)).

[0219] When ζ1max=ζ1(m), the corresponding cleaning time t(m) is the local optimal time Tmax.

[0220] Tmax=t(m).

[0221] Before step 1, the method further includes: optimizing the transmembrane pressure difference by using a transmembrane pressure difference optimization algorithm.

[0222] like Figure 5 , the transmembrane pressure difference optimization algorithm is:

[0223] Get the preset cleaning transmembrane pressure difference P' s , the second optimization range ΔP and the second step size Δp.

[0224] Initialize the second decision threshold

[0225] Initialization time update number k=0.

[0226] Let the value of the time update number k increase by 1, and use the formula P(k)=P' s -ΔP+kΔp determines that the current cleaning transmembrane pressure difference P(k) is the cleaning transmembrane pressure difference after the kth update.

[0227] Taking the current cleaning transmembrane pressure difference as the pre-cleaning transmembrane pressure difference, determine the post-cleaning transmembrane pressure difference P when the cleaning transmembrane pressure difference of the mud water concentration system reaches the cleaning transmembrane pressure difference after the kth update. e , total time of mud and water concentration process ∑T1, total cleaning time ∑T2.

[0228] Substitute the pre-cleaning transmembrane pressure difference, the total time of the mud water concentration process ∑T1 and the total cleaning time ∑T2 into the second optimization function, and the second optimization function value at the kth update is obtained. The first optimization function is: Among them, ζ2 is the second optimization function, k3 is the third weight coefficient, and k4 is the fourth weight coefficient.

[0229] It is determined whether the time update number k reaches the second determination threshold N3 to obtain a seventh determination result.

[0230] If the seventh judgment result is no, then return to step "increase the value of the time update number k by 1, and use the formula P(k)=P' s -ΔP+kΔp determines that the current cleaning transmembrane pressure difference P(k) is the cleaning transmembrane pressure difference after the kth update."

[0231] If the seventh judgment result is yes, then the cleaning transmembrane pressure difference corresponding to the maximum second optimization function value is determined to be the optimal transmembrane pressure difference.

[0232] Transmembrane pressure difference control parameter optimization: In the variable control method, the membrane cleaning is determined according to the set transmembrane pressure difference, and the set transmembrane pressure difference is locally optimized. Under the premise of the transmembrane pressure difference Ps set based on experience, given the optimization range ΔP, the transmembrane pressure difference P in P's -ΔP to P' s +ΔP range, the local optimal transmembrane pressure difference is found with a step size of Δp. The second optimization target parameter ζ2 is:

[0233]

[0234] Where k3 and k4 are weight coefficients, ranging from 0 to 1.

[0235] Cleaning time optimization process:

[0236] Step 1: Given the cleaning transmembrane pressure difference P' s , optimization range ΔP, weight coefficients k3 and k4, and second step length Δp.

[0237] Step 2: Calculation

[0238] Step 3: Cleaning transmembrane pressure difference: k = 1 to N3, cleaning transmembrane pressure difference P (k) = P' s -ΔP+kΔp, detect the transmembrane pressure difference P(k) and P before and after cleaning e , calculate the total time of the mud water concentration process and the total cleaning time ∑T1, ∑T2.

[0239] Calculate the second optimization function value.

[0240] Step 4: After N3 cleaning, find the maximum value of ζ2 ζ2max and the corresponding cleaning transmembrane pressure difference P(m).

[0241] ζ2max=MAX(ζ2(1), ζ2(2),..., ζ2(N3)).

[0242] When ζ2max=ζ2(m), the corresponding cleaning transmembrane pressure difference P(m) is the local optimal transmembrane pressure difference Pmax, Pmax=P(m).

[0243] 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.

[0244] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A mud water concentration system, characterized in that: It includes a concentration tank and a membrane filtration device. The concentration tank is used to store muddy water. The membrane filtration device is provided with a membrane water inlet, a membrane concentrated water inlet and a membrane clean water inlet. The membrane water inlet is connected with the concentration tank through a muddy water inlet pipe, and is used for muddy water to enter the membrane filtration device for filtration. The membrane clean water inlet is used for part of the water in the muddy water to flow out. The membrane concentrated water inlet is connected with the concentration tank through a muddy water return pipe, and is used for muddy water after part of the water is removed to flow back to the concentration tank to achieve circulation.

2. The muddy water concentration system according to claim 1, characterized in that: A membrane water inlet pump, a membrane water inlet valve, a one-way valve, a water inlet flowmeter and a water inlet pressure transmitter are arranged in sequence on the mud water inlet pipe along the water inlet direction, and a membrane concentrated water valve is arranged on the mud water return pipe; the membrane water purification port is connected to a clean water tank through a clean water outlet pipe, and a water production pressure transmitter, a membrane water production valve and a water production flowmeter are arranged in sequence on the clean water outlet pipe along the water outlet direction.

3. The muddy water concentration system according to claim 2, characterized in that: The membrane filtration device is a ceramic membrane filtration device, and the mud water concentration system further includes a flushing mechanism, which is used to flush the ceramic membrane filtration device; Wherein, the flushing mechanism includes an air washing mechanism, and the air washing mechanism includes an air supply device, and the air supply device is connected with the membrane water inlet of the ceramic membrane filter device through an air supply pipe, and is used to introduce compressed air into the ceramic membrane filter device to flush the ceramic membrane of the ceramic membrane filter device, and a compressed air valve and a one-way valve are sequentially arranged on the air supply pipe along the gas flow direction; the membrane concentrated water outlet of the ceramic membrane filter device is also connected to a mud discharge regulating tank through an upper discharge pipe, and is used to supply muddy water and air in the ceramic membrane filter device to enter the mud discharge regulating tank, and an upper discharge valve is arranged on the upper discharge pipe; The flushing mechanism also includes a clean water flushing mechanism, which includes a water supply pipe, the water inlet end of the water supply pipe is connected to the clean water tank, and a membrane backwashing water inlet valve, a backwashing pump and a one-way valve are sequentially arranged on the water supply pipe along the water flow direction, the outlet end of the water supply pipe is connected to the membrane concentrated water outlet through a membrane circulation water inlet pipe, which is used to supply clean water to enter the ceramic membrane filtration device to flush the ceramic membrane, and a membrane circulation water inlet valve is arranged on the membrane circulation water inlet pipe; the membrane water inlet of the ceramic membrane filtration device is also connected to the mud discharge regulating tank through a lower discharge pipe, which is used to supply muddy water formed after cleaning the ceramic membrane into the mud discharge regulating tank, and a lower discharge valve is arranged on the lower discharge pipe; The outlet end of the water supply pipe is also connected to the membrane water purification port through a membrane backwash pipe, so as to supply clean water to reversely enter the ceramic membrane filtration device to wash the ceramic membrane. A membrane backwash valve is provided on the membrane backwash pipe. The muddy water formed after washing the ceramic membrane is discharged through the membrane concentrated water port and the membrane water inlet, and enters the mud discharge regulating tank through the upper discharge pipe and the lower discharge pipe respectively. The membrane backwash pipe is arranged in parallel with the membrane circulation water inlet pipe. The flushing mechanism also includes a circulating alkali washing mechanism, which includes an alkali solution storage tank, which is connected to the membrane water inlet of the ceramic membrane filtration device through an alkali solution inlet pipe, and is used to supply alkali solution to the ceramic membrane filtration device to clean the ceramic membrane. An alkali solution dosing pump, an alkali solution valve and a one-way valve are sequentially arranged on the alkali solution inlet pipe along the alkali solution flow direction; the membrane water inlet is also connected to the water supply pipe between the backwash pump and the membrane backwash water inlet valve through a liquid medicine circulation pipeline, and the membrane water purification port is also connected to the liquid medicine circulation pipeline through a liquid medicine outlet pipe, a first membrane circulation water outlet valve is arranged on the liquid medicine circulation pipeline, and a second membrane circulation water outlet valve is arranged on the liquid medicine outlet pipe, and the backwash pump can drive the alkali solution to circulate in the ceramic membrane filtration device; The flushing mechanism also includes a circulating pickling mechanism, which includes an acid storage tank. The acid storage tank is connected to the membrane water inlet of the ceramic membrane filtration device through an acid inlet pipe, and is used to supply acid to enter the ceramic membrane filtration device to clean the ceramic membrane. An acid dosing pump, an acid valve and a one-way valve are sequentially arranged on the acid inlet pipe along the acid flow direction.

4. The muddy water concentration system according to claim 3, characterized in that: The liquid medicine circulation pipeline is also provided with a temperature transmitter.

5. A method for concentrating muddy water, characterized in that: The method is implemented by using the mud water concentration system according to any one of claims 1 to 4, comprising the steps of: The muddy water in the concentration tank is passed through the membrane filtration device for filtration, so that part of the water in the muddy water flows out through the membrane water purification port, and the muddy water after removing part of the water flows out through the membrane concentrated water port, and flows back to the concentration tank through the muddy water return pipe to achieve circulation; The above cycle process is repeated until the muddy water is concentrated to a water content reaching a set value.

6. A method for controlling a mud water concentration system, characterized in that: The muddy water concentration system control method is applied to the muddy water concentration system according to any one of claims 1 to 4, and the muddy water concentration system control method comprises: Obtaining a working mode selection instruction; the working mode selection instruction is a timing control mode instruction or a variable control mode instruction; When the working mode selection instruction is a timing control mode instruction, the mud water concentration system is controlled according to the timing control principle; When the working mode selection instruction is a variable control mode instruction, the mud water concentration system is controlled according to the variable control principle.

7. The mud water concentration system control method according to claim 6, characterized in that: The timing control principle is: When receiving the timing control mode instruction, the backwash times N1 is initialized to 0; Initialize the basic loop times N=0; Sending a mud water concentration process instruction to control the mud water concentration system to be in the mud water concentration process, and obtaining the mud water concentration process duration t0, until the mud water concentration process duration t0 reaches the mud water concentration process duration threshold T0, and initializing the mud water concentration process duration t0 = 0; Send out an air flushing process instruction to control the mud water concentration system to be in the air flushing process, and obtain the air flushing process duration t1, until the air flushing process duration t1 reaches the air flushing process duration threshold T1, and initialize the air flushing process duration t1 = 0; A clean water flushing process instruction is issued to control the mud water concentration system to be in the clean water flushing process, and the clean water flushing process duration t2 is obtained, until the clean water flushing process duration t2 reaches the clean water flushing process duration threshold T2, and the clean water flushing process duration t2 is initialized to 0; Increase the value of the basic cycle number N by 1; Determine whether the value of the basic cycle number N reaches the basic cycle number threshold value, and obtain a first determination result; If the first judgment result is no, then return to the step of "issuing a mud water concentration process instruction to control the mud water concentration system to be in the mud water concentration process, and obtaining the mud water concentration process duration t0, until the mud water concentration process duration t0 reaches the mud water concentration process duration threshold T0, and initializing the mud water concentration process duration t0 = 0"; If the first judgment result is yes, a water backwash process instruction is issued to control the mud water concentration system to be in the water backwash process, and the water backwash process duration t3 is obtained, until the water backwash process duration t0 reaches the water backwash process duration threshold T3, and the water backwash process duration t3 is initialized to 0; Increase the value of the backwash times N1 by 1; Determine whether the value of the backwashing times N1 reaches the working cycle times NY of the cyclic chemical washing interval, and obtain a second determination result; If the second judgment result is no, then return to step "initialize basic cycle times N = 0"; If the second judgment result is yes, a circulating chemical washing process instruction is issued to control the mud and water concentration system to be in the circulating chemical washing process, and the circulating chemical washing process duration t4 is obtained until the circulating chemical washing process duration t0 reaches the circulating chemical washing process duration threshold T4, the circulating chemical washing process duration t4 is initialized to 0, and the step "initialize backwash times N1 = 0" is returned.

8. The mud water concentration system control method according to claim 7, characterized in that: The variable control principle is: When receiving the variable control mode instruction, a mud water concentration process instruction is issued to control the mud water concentration system to be in the mud water concentration process, and obtain the real-time transmembrane pressure difference P until the real-time transmembrane pressure difference P reaches the transmembrane pressure difference P1 of the gas flushing process; Send out an air flushing process instruction to control the mud water concentration system to be in the air flushing process, and obtain the air flushing process duration t1, until the air flushing process duration t1 reaches the air flushing process duration threshold T1, and initialize the air flushing process duration t1 = 0; A clean water flushing process instruction is issued to control the mud water concentration system to be in the clean water flushing process, and the clean water flushing process duration t2 is obtained. When the clean water flushing process duration t2 reaches the clean water flushing process duration threshold T2, the transmembrane pressure difference P' at the end of the clean water flushing process is obtained, and the clean water flushing process duration t2 is initialized to 0; Determine whether the transmembrane pressure difference P' at the end of the clean water flushing process reaches the transmembrane pressure difference P1 during the gas flushing process, and obtain a third determination result; If the third judgment result is no, then return to the step of "issuing a mud water concentration process instruction to control the mud water concentration system to be in the mud water concentration process, and obtaining the real-time transmembrane pressure difference P until the real-time transmembrane pressure difference P reaches the transmembrane pressure difference P1 of the gas flushing process"; If the third judgment result is yes, a water backwash process instruction is issued to control the mud water concentration system to be in the water backwash process, and the water backwash process duration t3 is obtained, until the water backwash process duration t0 reaches the water backwash process duration threshold T3, the transmembrane pressure difference P" at the end of the water backwash process is obtained, and the water backwash process duration t3 is initialized to 0; Determine whether the transmembrane pressure difference P" at the end of the water backwash process reaches the transmembrane pressure difference P2 during the water backwash and chemical washing process, and obtain a fourth determination result; If the fourth judgment result is no, then return to the step of "issuing a mud water concentration process instruction to control the mud water concentration system to be in the mud water concentration process, and obtaining the real-time transmembrane pressure difference P until the real-time transmembrane pressure difference P reaches the transmembrane pressure difference P1 during the gas flushing process"; If the fourth judgment result is yes, a circulating chemical washing process instruction is issued to control the mud water concentration system to be in the circulating chemical washing process, and the duration t4 of the circulating chemical washing process is obtained, until the duration t0 of the circulating chemical washing process reaches the duration threshold T4 of the circulating chemical washing process, the transmembrane pressure difference P'' at the end of the circulating chemical washing process is obtained, and the duration t4 of the circulating chemical washing process is initialized to 0; Determine whether the transmembrane pressure difference p'' at the end of the circulating chemical washing process reaches the transmembrane pressure difference P2 during the water backwashing chemical washing process, and obtain a fifth determination result; If the result of the fifth judgment is no, then return to the step of "issuing a muddy water concentration process instruction to control the muddy water concentration system to be in the muddy water concentration process, and obtaining the real-time transmembrane pressure difference p, until the real-time transmembrane pressure difference P reaches the transmembrane pressure difference P1 of the gas flushing process"; If the fifth judgment result is yes, an alarm signal is issued.

9. The mud water concentration system control method according to claim 8, characterized in that: Before obtaining the work mode selection instruction, the method further includes: using a time optimization algorithm to optimize a cleaning process duration threshold; the cleaning process is one of a mud water concentration process, an air flushing process, a clean water flushing process, a water backwashing process or a circulating chemical washing process; Use time optimization algorithm to optimize the cleaning process duration threshold, including: Obtaining a preset working time T, a first optimization range ΔT and a first step distance Δt; Initialize the first decision threshold Initialization time update times k = 0; Let the value of the time update number k increase by 1, and use the formula t(k)=T-ΔT+kΔt to determine the current cleaning time; t(k) is the cleaning time after the kth update; Control the mud water concentration system to be in the cleaning process for the current cleaning time and obtain the transmembrane pressure difference P before cleaning s and the transmembrane pressure difference after cleaning P e ; The current cleaning time, the transmembrane pressure difference before cleaning P s and the transmembrane pressure difference after cleaning P e Substitute into the first optimization function to obtain the first optimization function value at the kth update; the first optimization function is: Wherein, ζ1 is the first optimization function, k1 is the first weight coefficient, and k2 is the second weight coefficient; Determine whether the time update number k reaches the first determination threshold N2, and obtain a sixth determination result; If the sixth judgment result is no, then return to step "increase the value of the time update number k by 1, and use the formula t(k)=T-ΔT+kΔt to determine the current cleaning time"; If the sixth judgment result is yes, the cleaning time corresponding to the maximum first optimization function value is determined as the cleaning process duration threshold.

10. The mud water concentration system control method according to claim 9, characterized in that: Before obtaining the working mode selection instruction, the method further includes: optimizing the transmembrane pressure difference by using a transmembrane pressure difference optimization algorithm; The transmembrane pressure difference optimization algorithm is: Get the preset cleaning transmembrane pressure difference P' s , a second optimization range ΔP and a second step distance Δp; Initialize the second decision threshold Initialization time update times k = 0; Let the value of the time update number k increase by 1, and use the formula P(k)=P' s -ΔP+kΔp determines the current cleaning transmembrane pressure difference; P(k) is the cleaning transmembrane pressure difference after the kth update; Taking the current cleaning transmembrane pressure difference as the pre-cleaning transmembrane pressure difference, determine the post-cleaning transmembrane pressure difference P when the cleaning transmembrane pressure difference of the mud water concentration system reaches the cleaning transmembrane pressure difference after the kth update. e , total time of mud water concentration process ∑T1, total cleaning time ∑T2; Substitute the pre-cleaning transmembrane pressure difference, the total time ∑T1 of the mud water concentration process and the total cleaning time ∑T2 into the second optimization function to obtain the second optimization function value at the kth update; the first optimization function is: Wherein, ζ2 is the second optimization function, k3 is the third weight coefficient, and k4 is the fourth weight coefficient; Determine whether the time update number k reaches the second determination threshold N3, and obtain a seventh determination result; If the seventh judgment result is no, then return to step "increase the value of the time update number k by 1, and use the formula P(k)=P' s -ΔP+kΔp determines the current cleaning transmembrane pressure difference; P(k) is the cleaning transmembrane pressure difference after the kth update"; If the seventh judgment result is yes, then the cleaning transmembrane pressure difference corresponding to the maximum second optimization function value is determined to be the optimal transmembrane pressure difference.

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