A mine water inorganic membrane-organic membrane hybrid direct filtration purification method

Abstract

This invention provides a hybrid inorganic-organic membrane direct filtration method for purifying mine water. This method first calculates and obtains parameters related to water purification. Then, the mine water is filtered using the hybrid inorganic-organic membrane direct filtration system based on the calculated parameters. This hybrid inorganic-organic membrane direct filtration method for purifying mine water, by coupling organic and inorganic membranes, can reduce the operating energy consumption of mine water treatment, improve shock resistance, and ensure excellent and stable water quality across a wide range of suspended solids concentrations.

Description

Technical Field

[0001] The present invention belongs to the technical field of water purification, relates to a water purification method, and specifically relates to a mine water inorganic membrane-organic membrane hybrid direct filtration purification method. Background Art

[0002] With the improvement of mine water quality in recent years, the traditional coagulation sedimentation + sand filtration / multi-media filtration process has high treatment costs due to its long process, large floor space, and the need to add coagulants.

[0003] Organic membranes (such as polytetrafluoroethylene ultrafiltration membranes) and inorganic membranes (such as silicon carbide ceramic membranes) are the two most commonly used short-process direct filtration membranes. These two membranes can directly purify turbid mine water without adding coagulants. However, the two membrane systems are applicable to different suspended solids concentration ranges. When the suspended solids concentration is outside the applicable range, the energy consumption of water treatment will increase, the impact resistance will decrease, and the water quality of the produced water will be unstable and will decline. Summary of the Invention

[0004] In view of the defects and shortcomings of the existing technology, the purpose of the present invention is to provide a mine water inorganic membrane-organic membrane hybrid direct filtration purification method to solve the technical problem that the existing technology for purifying mine water is difficult to stably achieve high-quality water production within a wide concentration range.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A mine water inorganic membrane-organic membrane hybrid direct filtration purification method, the method adopts a mine water inorganic membrane-organic membrane hybrid direct filtration purification system; the method specifically comprises the following steps:

[0007] Step 1: Obtain critical suspended solids concentration:

[0008] Take a series of influent suspended solids concentration values, calculate the operating cost of the organic membrane filter corresponding to each influent suspended solids concentration value, then draw a scatter plot based on the calculation results and connect adjacent scatter plots with straight lines to obtain the influent suspended solids concentration value-organic membrane filter operating cost curve S1; calculate the operating cost of the inorganic membrane filter corresponding to each influent suspended solids concentration value, then draw a scatter plot based on the calculation results and connect adjacent scatter plots with straight lines to obtain the influent suspended solids concentration value-inorganic membrane filter operating cost curve S2; take the intersection of the influent suspended solids concentration value-organic membrane filter operating cost curve S1 and the influent suspended solids concentration value-inorganic membrane filter operating cost curve S2, and the influent suspended solids concentration value corresponding to the intersection is the critical suspended solids concentration value.

[0009] Step 2: Get the suspended solids concentration in the regulating tank:

[0010] Substitute the cross-flow multiple of the organic membrane filter, the multiple of the clean water output of the organic membrane filter to its own output, and the critical suspended solids concentration obtained in step 1 into Formula I to calculate and obtain the suspended solids concentration in the regulating tank; Formula I is:

[0011] Formula I.

[0012] Where:

[0013] Indicates the suspended solids concentration in the equalization tank.

[0014] Indicates the cross-flow multiple of the organic membrane filter.

[0015] It represents the multiple of the clean water output of the organic membrane filter to its own output, which is 1.

[0016] Step 3: Obtain the expression for the suspended solids concentration in the intermediate water tank:

[0017] Substitute the cross-flow multiple of the organic membrane filter, the multiple of the clean water output of the organic membrane filter to its own output, and the suspended solids concentration of the regulating tank obtained in step 2 into formula II to calculate and obtain the suspended solids concentration of the intermediate water tank; the formula II is:

[0018] Formula II.

[0019] Where:

[0020] Indicates the suspended matter concentration in the intermediate water tank.

[0021] Step 4: Get the amount of concentrated water entering the intermediate water tank:

[0022] Substitute formula I in step two into formula II in step three to obtain formula III for the suspended solids concentration in the intermediate water tank; consider the suspended solids concentration of the raw water and the initial suspended solids concentration in the intermediate water tank to be equal, then obtain formula IV; then substitute formula III into formula IV to obtain formula V; then substitute the suspended solids concentration of the raw water, the amount of water entering the organic membrane filter, the clean water output of the organic membrane filter, and the value of the critical suspended solids concentration in step one into formula V, calculate and obtain the multiple of the amount of concentrated water entering the intermediate water tank to the clean water output of the organic membrane filter, and multiply this multiple by the clean water output of the organic membrane filter to obtain the amount of concentrated water entering the intermediate water tank.

[0023] The formula III is:

[0024] Formula III.

[0025] The formula IV is:

[0026] Formula IV.

[0027] Where:

[0028] Indicates the suspended solids concentration of raw water.

[0029] It indicates the multiple of the concentrated water volume entering the intermediate water tank to the clean water output of the organic membrane filter.

[0030] The formula V is:

[0031] Formula V.

[0032] Step 5: Obtain the amount of concentrated water returned to the regulating tank:

[0033] Substitute the cross-flow multiple of the organic membrane filter and the multiple of the amount of concentrated water entering the intermediate water tank obtained in step 4 to the clean water output of the organic membrane filter into formula VI, calculate and obtain the multiple of the amount of concentrated water returned to the regulating tank to the clean water output of the organic membrane filter, and multiply this multiple by the clean water output of the organic membrane filter to obtain the amount of concentrated water returned to the regulating tank.

[0034] The formula VI is:

[0035] Formula VI.

[0036] Where:

[0037] It indicates the multiple of the concentrated water volume returned to the equalization tank to the clean water output of the organic membrane filter.

[0038] The inorganic membrane-organic membrane hybrid direct filtration purification system for mine water includes a mine water inlet pipe, the outlet end of the mine water inlet pipe is connected to the first water inlet end of the regulating tank, the first water outlet end of the regulating tank is connected to the water inlet end of the preliminary filtration pipe, the first water outlet end of the preliminary filtration pipe is connected to the first water inlet end of the organic membrane filter, the first water outlet end of the organic membrane filter is connected to the organic membrane water production pipe; the second water outlet end of the organic membrane filter is connected to the water inlet end of the organic membrane concentrated water supply pipe, the first water outlet end of the organic membrane concentrated water supply pipe is connected to the water inlet end of the intermediate water tank; the second water outlet end of the organic membrane concentrated water supply pipe is connected to the water inlet end of the organic membrane concentrated water return pipe, and the water outlet end of the organic membrane concentrated water return pipe is connected to the second water inlet end of the regulating tank.

[0039] The water outlet end of the intermediate water tank is connected to the water inlet end of the transition conveying pipeline, the water outlet end of the transition conveying pipeline is connected to the water inlet end of the inorganic membrane filter, the first water outlet end of the inorganic membrane filter is connected to the inorganic membrane water production pipeline, the second water outlet end of the inorganic membrane filter is connected to the water inlet end of the inorganic membrane concentrated water conveying pipeline, and the water outlet end of the inorganic membrane concentrated water conveying pipeline is connected to the coal slime concentration tank.

[0040] The preliminary filtration pipeline is provided with a constant flow pump, the organic membrane concentrated water delivery pipeline is provided with an intermediate water tank inlet regulating valve, and the organic membrane concentrated water return pipeline is provided with an organic membrane concentrated water cross-flow valve.

[0041] The present invention also has the following technical features:

[0042] Specifically, the method further includes step six; said step six specifically includes the following process:

[0043] Start the mine water inorganic membrane-organic membrane hybrid direct filtration purification system, adjust the intermediate water tank inlet regulating valve to control the amount of concentrated water entering the intermediate water tank, so that the amount of concentrated water entering the intermediate water tank reaches the value calculated in step four; adjust the organic membrane concentrated water cross-flow valve to control the amount of concentrated water returning to the regulating tank, so that the amount of concentrated water returning to the regulating tank reaches the value calculated in step five.

[0044] Specifically, the method further includes step seven; said step seven specifically includes the following process:

[0045] After completing the water volume adjustment in step six, the system starts to officially operate. The mine water first enters the regulating tank for sedimentation, then flows into the preliminary filtration pipe and enters the organic membrane filter driven by the constant flow pump. The clean water produced by the organic membrane filter flows into the organic membrane water production pipe, and the concentrated water produced by the organic membrane filter enters the inorganic membrane filter. The clean water produced by the inorganic membrane filter flows into the inorganic membrane water production pipe, and the concentrated water produced by the inorganic membrane filter flows into the coal slime concentration tank through the inorganic membrane concentrated water delivery pipe.

[0046] Specifically, the mine water inorganic membrane-organic membrane hybrid direct filtration purification system also includes a first backwash water tank, the water outlet end of the first backwash water tank is connected to the water inlet end of the first backwash pipe, the water outlet end of the first backwash pipe is connected to the second water inlet end of the organic membrane filter, and a first backwash water pump is provided on the first backwash pipe.

[0047] The mine water inorganic membrane-organic membrane hybrid direct filtration purification system also includes a high-pressure gas delivery pipeline, the gas outlet end of the high-pressure gas delivery pipeline is connected to the gas inlet end of the second backwash water tank, the water outlet end of the second backwash water tank is connected to the water inlet end of the second backwash pipeline, and the water outlet end of the second backwash pipeline is connected to the water inlet end of the inorganic membrane filter.

[0048] The method further includes step eight; said step eight specifically includes the following steps:

[0049] Step 8.1, backwashing of organic membrane filter:

[0050] When the difference between the inlet water pressure and the produced water pressure of the organic membrane filter reaches the design upper limit, the organic membrane filter is backwashed through the first backwash water tank, the first backwash pipe and the first backwash water pump. The concentrated water generated after the backwash is completed is discharged through the mud discharge pipe of the organic membrane filter.

[0051] Step 8.2, backwashing of inorganic membrane filter:

[0052] When the difference between the inlet water pressure and the produced water pressure of the inorganic membrane filter reaches the design upper limit, the inorganic membrane filter is backwashed through the high-pressure gas transmission pipeline, the second backwash water tank and the second backwash pipeline. The concentrated water generated after the backwash is discharged through the mud discharge pipe of the inorganic membrane filter.

[0053] Specifically, in step 8.1, the backwashing time for each time is 1 to 3 minutes, and the total backwashing time is 0.5 to 4 hours.

[0054] Specifically, in step 8.2, the inlet pressure of the high-pressure gas is controlled at 2 to 6 bar during backwashing, and the total backwashing time is 0.5 to 4 hours.

[0055] Specifically, the inorganic membrane-organic membrane hybrid direct filtration purification system for mine water also includes a clean water tank, an alkali washing tank and a pickling tank; the water outlet end of the clean water tank is connected to the water inlet end of the clean water tank outlet pipe, the water outlet end of the alkali washing tank is connected to the water inlet end of the alkali washing tank outlet pipe, and the water outlet end of the pickling tank is connected to the water inlet end of the pickling tank outlet pipe; the water outlet ends of the clean water tank outlet pipe, the alkali washing tank outlet pipe and the pickling tank outlet pipe are all connected to the water inlet end of the cleaning liquid delivery main pipe, the first water outlet end of the cleaning liquid delivery main pipe is connected to the water inlet end of the cleaning liquid first delivery branch pipe, the water outlet end of the cleaning liquid first delivery branch pipe is connected to the preliminary filtration pipe, the second water outlet end of the cleaning liquid delivery main pipe is connected to the water inlet end of the cleaning liquid second delivery branch pipe, and the water outlet end of the cleaning liquid second delivery branch pipe is connected to the transition delivery pipe.

[0056] The clean water tank outlet pipe, the alkali washing tank outlet pipe and the acid washing tank outlet pipe are respectively provided with liquid outlet control valves; the cleaning liquid delivery main pipe is provided with a cleaning pump, the cleaning liquid first delivery branch pipe is provided with a cleaning liquid first control valve, and the cleaning liquid second delivery branch pipe is provided with a cleaning liquid second control valve.

[0057] The method further includes step nine; said step nine specifically includes the following steps:

[0058] Step 9.1, chemical cleaning of organic membrane filter:

[0059] When the organic membrane pollution of the organic membrane filter reaches an irreversible level, first open the liquid outlet control valve and the first cleaning liquid control valve on the clean water tank outlet pipe and start the cleaning pump. Driven by the cleaning pump, the water in the clean water tank enters the organic membrane filter through the clean water tank outlet pipe, the cleaning liquid delivery main pipe and the cleaning liquid delivery branch pipe, and the organic membrane filter is washed for the first time.

[0060] After the first water washing is completed, close the liquid outlet control valve on the clean water tank outlet pipe, open the liquid outlet control valve on the alkali washing tank outlet pipe, and under the drive of the cleaning pump, the alkali washing liquid in the alkali washing tank enters the organic membrane filter through the alkali washing tank outlet pipe, the cleaning liquid delivery main pipe and the cleaning liquid first delivery branch pipe to perform alkali washing on the organic membrane filter.

[0061] After the alkaline washing is completed, the liquid outlet control valve on the alkaline washing tank outlet pipe is closed, and the liquid outlet control valve on the clean water tank outlet pipe is opened again for a second water washing. The second water washing time is 2 to 5 minutes. After the second water washing is completed, the liquid outlet control valve on the clean water tank outlet pipe is closed, and the liquid outlet control valve on the acid washing tank outlet pipe is opened. Driven by the cleaning pump, the pickling liquid in the pickling tank enters the organic membrane filter through the pickling tank outlet pipe, the cleaning liquid delivery main pipe and the cleaning liquid first delivery branch pipe to pickle the organic membrane filter.

[0062] Step 9.2, chemical cleaning of inorganic membrane filter:

[0063] When the organic membrane pollution of the inorganic membrane filter reaches an irreversible level, first open the liquid outlet control valve and the second control valve of the cleaning liquid on the clean water tank outlet pipe and start the cleaning pump. Driven by the cleaning pump, the water in the clean water tank enters the inorganic membrane filter through the clean water tank outlet pipe, the cleaning liquid delivery main pipe and the cleaning liquid delivery branch pipe, and the inorganic membrane filter is washed for the first time.

[0064] After the first water washing is completed, close the liquid outlet control valve on the clean water tank outlet pipe, open the liquid outlet control valve on the alkali washing tank outlet pipe, and under the drive of the cleaning pump, the alkali washing liquid in the alkali washing tank enters the inorganic membrane filter through the alkali washing tank outlet pipe, the cleaning liquid delivery main pipe and the cleaning liquid second delivery branch pipe to perform alkali washing on the inorganic membrane filter.

[0065] After the alkaline washing is completed, close the liquid outlet control valve on the alkaline washing tank outlet pipe, open the liquid outlet control valve on the clean water tank outlet pipe again, and carry out the second water washing. The second water washing time is 2 to 5 minutes. After the second water washing is completed, close the liquid outlet control valve on the clean water tank outlet pipe, open the liquid outlet control valve on the acid washing tank outlet pipe, and drive the cleaning pump. The pickling liquid in the pickling tank enters the inorganic membrane filter through the pickling tank outlet pipe, the cleaning liquid delivery main pipe and the cleaning liquid second delivery branch pipe to pickle the inorganic membrane filter.

[0066] Specifically, in steps 9.1 and 9.2, the first water washing time is 3 to 10 minutes.

[0067] Specifically, in steps 9.1 and 9.2, the alkaline washing time is 3 to 10 minutes; the alkaline washing solution is an aqueous solution of sodium hypochlorite and sodium hydroxide, and the mass fraction of sodium hypochlorite and sodium hydroxide is 0.1% to 1.5%.

[0068] Specifically, in steps 9.1 and 9.2, the pickling time is 3 to 10 minutes; the pickling solution is an aqueous solution of citric acid, and the mass fraction of citric acid is 0.2% to 0.6%.

[0069] Compared with the prior art, the present invention has the following beneficial technical effects:

[0070] (I) The inorganic membrane-organic membrane hybrid direct filtration purification method of mine water of the present invention couples the organic membrane and the inorganic membrane together, which can reduce the operating energy consumption of mine water treatment, improve the impact resistance, and ensure the excellent and stable water quality of the produced water over a wide range of suspended matter concentrations.

[0071] (II) The inorganic membrane-organic membrane hybrid direct filtration purification method for mine water of the present invention quantitatively considers the membrane material cost and operating costs, and provides a calculation formula for dynamically adjusting the two membrane purification systems to achieve the lowest operating cost. This method can give full play to the advantages of low treatment cost per ton of water of organic membrane under conditions of medium and low suspended matter concentrations and relatively low treatment cost per ton of water of inorganic membrane under conditions of high suspended matter, taking into account the overall treatment cost and high-quality water production.

[0072] (III) The present invention's hybrid inorganic membrane-organic membrane direct filtration purification system for mine water uses a regulating tank for initial sedimentation treatment of turbid mine water. This water then passes through a hair filter to further remove impurities. The water then enters an organic membrane filter for initial concentration. The water produced by the organic membrane filter enters a clear water tank, with some of the concentrated water returning to the tank, while another portion enters an intermediate water tank. The initial concentrated water from the intermediate water tank is further concentrated by an inorganic membrane filter. The concentrated slime water enters a concentrating tank for coagulation and sedimentation, and the clear water from the concentrating tank returns to the regulating tank. This process eliminates the need for adding coagulants, enabling direct purification of turbid mine water. This significantly reduces treatment costs while avoiding irreversible membrane fouling caused by improper reagent addition. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] Figure 1 This is a schematic diagram of the overall structure of the inorganic membrane-organic membrane hybrid direct filtration purification system for mine water.

[0074] Figure 2 The operating cost curve S1 of the influent suspended solids concentration-organic membrane filter and the operating cost curve S2 of the influent suspended solids concentration-inorganic membrane filter when the electricity fee is 1 yuan / kWh.

[0075] Figure 3 The operating cost curve S1 of the influent suspended solids concentration-organic membrane filter and the operating cost curve S2 of the influent suspended solids concentration-inorganic membrane filter when the electricity fee is 0.5 yuan / kWh.

[0076] Figure 4 When the electricity fee is 1 yuan / kWh and the concentration of suspended solids in raw water is Schematic diagram of the water purification process when the concentration is 300 mg / L.

[0077] Figure 5 When the electricity fee is 1 yuan / kWh and the concentration of suspended solids in raw water is Schematic diagram of the water purification process when the concentration is 600 mg / L.

[0078] The meanings of the numbers in the figure are: 1- mine water inlet pipeline, 2- regulating tank, 3- preliminary filtration pipeline, 4- organic membrane filter, 5- organic membrane water production pipeline, 6- organic membrane concentrated water delivery pipeline, 7- intermediate water tank, 8- organic membrane concentrated water return pipeline, 9- transition delivery pipeline, 10- inorganic membrane filter, 11- inorganic membrane water production pipeline, 12- inorganic membrane concentrated water delivery pipeline, 13- coal slime concentration tank, 14- constant flow pump, 15- intermediate water tank inlet regulating valve, 16- organic membrane concentrated water cross-flow valve, 17- first backwash water tank, 18- first backwash pipeline, 19- first backwash water pump, 20- high-pressure gas delivery pipeline, 21- second backwash water tank, 22- second backwash Cleaning pipeline, 23-clean water tank, 24-alkaline washing tank, 25-acid washing tank, 26-clean water tank outlet pipeline, 27-alkaline washing tank outlet pipeline, 28-acid washing tank outlet pipeline, 29-cleaning liquid delivery main pipeline, 30-cleaning liquid first delivery branch pipeline, 31-cleaning liquid second delivery branch pipeline, 32-liquid outlet control valve, 33-cleaning pump, 34-cleaning liquid first control valve, 35-cleaning liquid second control valve, 36-first cleaning water pipeline, 37-second cleaning water pipeline, 38-gas storage tank, 39-gas delivery pipeline, 40-air compressor, 41-air inlet valve, 42-impurity filter, 43-inorganic membrane concentrated water cross-flow valve, 44-sludge discharge pipe, 45-sludge discharge valve.

[0079] The technical solution of the present invention is further described below in conjunction with embodiments. DETAILED DESCRIPTION

[0080] In the present invention:

[0081] Critical suspended solids concentration The actual meaning is: the concentration of suspended solids in the inlet water when the operating costs of the organic membrane filter and the inorganic membrane filter are equal.

[0082] It should be noted that all components and devices used in the present invention, unless otherwise specified, are components and devices known in the art, for example:

[0083] The organic membrane filter 4 is a conventional organic membrane filter known in the prior art, such as a polytetrafluoroethylene membrane filter.

[0084] The inorganic membrane filter 10 adopts a conventional inorganic membrane filter known in the prior art, such as a silicon carbide ceramic membrane filter.

[0085] In accordance with the above technical solution, specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent changes made on the basis of the technical solution of this application fall within the protection scope of the present invention.

[0086] Example 1:

[0087] This embodiment provides a mine water inorganic membrane-organic membrane hybrid direct filtration purification system, such as Figure 1 As shown, it includes a mine water inlet pipeline 1, the outlet end of the mine water inlet pipeline 1 is connected to the first water inlet end of the regulating tank 2, the first water outlet end of the regulating tank 2 is connected to the water inlet end of the preliminary filtration pipeline 3, the first water outlet end of the preliminary filtration pipeline 3 is connected to the first water inlet end of the organic membrane filter 4, the first water outlet end of the organic membrane filter 4 is connected to the organic membrane water production pipeline 5; the second water outlet end of the organic membrane filter 4 is connected to the water inlet end of the organic membrane concentrated water supply pipeline 6, the first water outlet end of the organic membrane concentrated water supply pipeline 6 is connected to the water inlet end of the intermediate water tank 7; the second water outlet end of the organic membrane concentrated water supply pipeline 6 is connected to the water inlet end of the organic membrane concentrated water return pipeline 8, and the outlet end of the organic membrane concentrated water return pipeline 8 is connected to the second water inlet end of the regulating tank 2.

[0088] The water outlet of the intermediate water tank 7 is connected to the water inlet of the transition delivery pipeline 9, which is in turn connected to the water inlet of the inorganic membrane filter 10. The first water outlet of the inorganic membrane filter 10 is connected to the inorganic membrane water production pipeline 11, and the second water outlet of the inorganic membrane filter 10 is connected to the water inlet of the inorganic membrane brine delivery pipeline 12. The water outlet of the inorganic membrane brine delivery pipeline 12 is connected to the coal slime concentration tank 13. A constant flow pump 14 is provided on the primary filtration pipeline 3, an intermediate water tank inlet regulating valve 15 is provided on the organic membrane brine delivery pipeline 6, and an organic membrane brine cross-flow valve 16 is provided on the organic membrane brine return pipeline 8.

[0089] In this embodiment, the regulating tank 2 is used to precipitate the mine water to remove large particles of coal slime. The coal slime concentration tank 13 can precipitate the concentrated water produced by the inorganic membrane filter 10 again and recycle the upper clear water.

[0090] In this embodiment, the water inlet of the organic membrane filter 4 is controlled by the constant flow pump 14, so that the clean water output of the organic membrane filter can be kept basically constant. When the organic membrane in the organic membrane filter 4 is contaminated and blocked, the power of the constant flow pump 14 is increased and the water inlet pressure is increased. When the difference between the water inlet pressure and the produced water pressure reaches the design upper limit, the system enters backwashing.

[0091] As a specific solution of this embodiment, the system also includes a first backwash water tank 17, the water outlet end of the first backwash water tank 17 is connected to the water inlet end of the first backwash pipe 18, the water outlet end of the first backwash pipe 18 is connected to the second water inlet end of the organic membrane filter 4, and a first backwash water pump 19 is provided on the first backwash pipe 18.

[0092] In this embodiment, when the system enters backwashing, the water in the first backwash water tank 17, driven by the first backwash water pump 19, enters the organic membrane filter 4 through the first backwash pipe 18 to clean the organic membrane filter 4, thereby avoiding the phenomenon of system operation being terminated due to blockage of the organic membrane filter 4.

[0093] As a specific solution of this embodiment, the system also includes a high-pressure gas delivery pipeline 20, the gas outlet end of the high-pressure gas delivery pipeline 20 is connected to the gas inlet end of the second backwash water tank 21, the water outlet end of the second backwash water tank 21 is connected to the water inlet end of the second backwash pipeline 22, and the water outlet end of the second backwash pipeline 22 is connected to the water inlet end of the inorganic membrane filter 10.

[0094] In this embodiment, when the system enters backwashing, high-pressure gas enters the second backwash water tank 21 and mixes with the water to form a gas-liquid mixture. The gas-liquid mixture enters the inorganic membrane filter 10 through the second backwash pipe 22 to clean the inorganic membrane filter 10, thereby avoiding the phenomenon of system operation being terminated due to blockage of the inorganic membrane filter 10.

[0095] As a specific solution of this embodiment, the system also includes a clean water tank 23, an alkali washing tank 24 and a pickling tank 25; the water outlet end of the clean water tank 23 is connected to the water inlet end of the clean water tank outlet pipe 26, the water outlet end of the alkali washing tank 24 is connected to the water inlet end of the alkali washing tank outlet pipe 27, and the water outlet end of the pickling tank 25 is connected to the water inlet end of the pickling tank outlet pipe 28; the water outlet ends of the clean water tank outlet pipe 26, the alkali washing tank outlet pipe 27 and the pickling tank outlet pipe 28 are all connected to the water inlet end of the cleaning liquid delivery main pipe 29, the first water outlet end of the cleaning liquid delivery main pipe 29 is connected to the water inlet end of the cleaning liquid first delivery branch pipe 30, the water outlet end of the cleaning liquid first delivery branch pipe 30 is connected to the preliminary filtration pipe 3, the second water outlet end of the cleaning liquid delivery main pipe 29 is connected to the water inlet end of the cleaning liquid second delivery branch pipe 31, and the water outlet end of the cleaning liquid second delivery branch pipe 31 is connected to the transition delivery pipe 9.

[0096] In this embodiment, the clean water tank 23 , the alkaline cleaning tank 24 and the acid cleaning tank 25 are respectively filled with water, alkaline cleaning solution and acid cleaning solution for chemically cleaning the organic membrane filter 4 and the inorganic membrane filter 10 .

[0097] As a specific solution of this embodiment, liquid outlet control valves 32 are respectively provided on the clean water tank outlet pipe 26, the alkali washing tank outlet pipe 27 and the pickling tank outlet pipe 28; a cleaning pump 33 is provided on the cleaning liquid delivery main pipe 29, a cleaning liquid first control valve 34 is provided on the cleaning liquid first delivery branch pipe 30, and a cleaning liquid second control valve 35 is provided on the cleaning liquid second delivery branch pipe 31.

[0098] In this embodiment, the output and flow rate of water, alkaline washing liquid and acid washing liquid are controlled by the liquid outlet control valve 32 , and the cleaning pump 33 is used to pump water, alkaline washing liquid and acid washing liquid into the organic membrane filter 4 and the inorganic membrane filter 10 .

[0099] As a specific solution of this embodiment, the third water outlet of the organic membrane filter 4 is connected to the first cleaning water pipe 36 ; the third water outlet of the inorganic membrane filter 10 is connected to the second cleaning water pipe 37 .

[0100] In this embodiment, during the process of chemical cleaning of the organic membrane filter 4 and the inorganic membrane filter 10, the alkaline washing liquid and the acid washing liquid flowing out of the organic membrane filter 4 and the inorganic membrane filter 10 can be discharged through the first cleaning water pipe 36 and the second cleaning water pipe 37, or the water outlet ends of the first cleaning water pipe 36 and the second cleaning water pipe 37 can be connected to the alkaline washing tank 24 and the acid washing tank 25, so that the alkaline washing liquid and the acid washing liquid can flow back into the alkaline washing tank 24 and the acid washing tank 25, thereby realizing the recycling of the alkaline washing liquid and the acid washing liquid.

[0101] As a specific solution of this embodiment, the system also includes an air storage tank 38, the air outlet end of the air storage tank 38 is connected to the air inlet end of the gas delivery pipe 39, and the air outlet end of the gas delivery pipe 39 is connected to the air inlet end of the organic membrane filter 4; an air compressor 40 and an air intake valve 41 are provided on the gas delivery pipe 39, and the air intake valve 41 is located between the organic membrane filter 4 and the air compressor 40.

[0102] In this embodiment, the gas delivery pipe 39 is connected to the aeration hole set at the bottom of the organic membrane filter 4. The gas in the gas storage tank 38 enters the organic membrane filter 4 through the gas delivery pipe 39 and the aeration hole under the drive of the air compressor 40. The aeration of the organic membrane filter 4 is achieved through the above process.

[0103] As a specific solution of this embodiment, an impurity filter 42 is provided on the preliminary filtration pipe 3, and the impurity filter 42 is located between the regulating tank 2 and the constant flow pump 14. In this embodiment, the impurity filter 42 is used to remove smaller impurities such as hair or leaves in the mine water.

[0104] As a specific solution of this embodiment, an inorganic membrane concentrated water cross-flow valve 43 is provided on the inorganic membrane concentrated water delivery pipeline 12 .

[0105] As a specific solution of this embodiment, mud discharge pipes 44 are respectively provided at the bottom of the regulating tank 2, the organic membrane filter 4, the intermediate water tank 7, and the inorganic membrane filter 10. Mud discharge pipes 44 are provided with mud discharge valves 45. The mud discharge pipes 44 are used to discharge sludge or deposited concentrated water.

[0106] Example 2:

[0107] This embodiment provides a method for purifying mine water by inorganic membrane-organic membrane hybrid direct filtration. The method adopts the mine water inorganic membrane-organic membrane hybrid direct filtration purification system in Example 1. The method specifically comprises the following steps:

[0108] Step 1: Obtain critical suspended solids concentration:

[0109] Take a series of influent suspended solids concentration values, calculate the operating cost of the organic membrane filter corresponding to each influent suspended solids concentration value, then draw a scatter plot based on the calculation results and connect adjacent scatter plots with straight lines to obtain the influent suspended solids concentration value-organic membrane filter operating cost curve S1; calculate the operating cost of the inorganic membrane filter corresponding to each influent suspended solids concentration value, then draw a scatter plot based on the calculation results and connect adjacent scatter plots with straight lines to obtain the influent suspended solids concentration value-inorganic membrane filter operating cost curve S2; take the intersection of the influent suspended solids concentration value-organic membrane filter operating cost curve S1 and the influent suspended solids concentration value-inorganic membrane filter operating cost curve S2, and the influent suspended solids concentration value corresponding to the intersection is the critical suspended solids concentration value.

[0110] Step 2: Get the suspended solids concentration in the regulating tank:

[0111] Substitute the cross-flow multiple of the organic membrane filter, the multiple of the clean water output of the organic membrane filter to its own output, and the critical suspended solids concentration obtained in step 1 into Formula I to calculate and obtain the suspended solids concentration in the regulating tank; Formula I is:

[0112] Formula I.

[0113] Where:

[0114] Indicates the suspended solids concentration in the equalization tank.

[0115] It indicates the cross-flow multiple of the organic membrane filter. This parameter can take a conventional value, generally 0.3 to 2.

[0116] It represents the multiple of the clean water production of the organic membrane filter to itself, which is 1. In this embodiment, the clean water production of the organic membrane filter is obtained according to the membrane flux, membrane area, operating time and water production rate coefficient according to the conventional calculation method known in the prior art.

[0117] Step 3: Obtain the expression for the suspended solids concentration in the intermediate water tank:

[0118] Substitute the cross-flow multiple of the organic membrane filter, the multiple of the clean water output of the organic membrane filter to its own output, and the suspended solids concentration of the regulating tank obtained in step 2 into formula II to calculate and obtain the suspended solids concentration of the intermediate water tank; the formula II is:

[0119] Formula II.

[0120] Where:

[0121] Indicates the suspended matter concentration in the intermediate water tank.

[0122] Step 4: Get the amount of concentrated water entering the intermediate water tank:

[0123] Substitute formula I in step two into formula II in step three to obtain formula III for the suspended solids concentration in the intermediate water tank; consider the suspended solids concentration of the raw water and the initial suspended solids concentration in the intermediate water tank, i.e., the suspended solids concentration of the water flowing in the organic membrane concentrated water delivery pipeline 6, to be equal, and then obtain formula IV; then substitute formula III into formula IV to obtain formula V; then substitute the suspended solids concentration of the raw water, the amount of water entering the organic membrane filter, the clean water output of the organic membrane filter, and the value of the critical suspended solids concentration in step one into formula V, calculate and obtain the multiple of the amount of concentrated water entering the intermediate water tank to the clean water output of the organic membrane filter, and multiply this multiple by the clean water output of the organic membrane filter to obtain the amount of concentrated water entering the intermediate water tank.

[0124] The formula III is:

[0125] Formula III.

[0126] The formula IV is:

[0127] Formula IV.

[0128] Where:

[0129] It represents the suspended matter concentration of raw water, that is, the suspended matter concentration of mine water flowing into the mine water inlet pipe 1.

[0130] It indicates the multiple of the concentrated water volume entering the intermediate water tank to the clean water output of the organic membrane filter.

[0131] The formula V is:

[0132] Formula V.

[0133] Step 5: Obtain the amount of concentrated water returned to the regulating tank:

[0134] Substitute the cross-flow multiple of the organic membrane filter and the multiple of the amount of concentrated water entering the intermediate water tank obtained in step 4 to the clean water output of the organic membrane filter into formula VI, calculate and obtain the multiple of the amount of concentrated water returned to the regulating tank to the clean water output of the organic membrane filter, and multiply this multiple by the clean water output of the organic membrane filter to obtain the amount of concentrated water returned to the regulating tank.

[0135] The formula VI is:

[0136] Formula VI.

[0137] Where:

[0138] It indicates the multiple of the concentrated water volume returned to the equalization tank to the clean water output of the organic membrane filter.

[0139] Step 6: Adjust the water volume:

[0140] Start the system, adjust the intermediate water tank inlet regulating valve 15 to control the amount of concentrated water entering the intermediate water tank, so that the amount of concentrated water entering the intermediate water tank reaches the value calculated in step four; adjust the organic membrane concentrated water cross-flow valve 16 to control the amount of concentrated water returning to the regulating tank, so that the amount of concentrated water returning to the regulating tank reaches the value calculated in step five.

[0141] Step 7: Run the system:

[0142] After completing the water volume adjustment in step six, the system starts to officially operate. The mine water first enters the regulating tank 2 for sedimentation, then flows into the preliminary filtration pipe 3 and enters the organic membrane filter 4 driven by the constant flow pump 14. The clean water produced by the organic membrane filter 4 flows into the organic membrane water production pipe 5. The concentrated water produced by the organic membrane filter 4 enters the inorganic membrane filter 10. The clean water produced by the inorganic membrane filter 10 flows into the inorganic membrane water production pipe 11. The concentrated water produced by the inorganic membrane filter 10 flows into the coal slime concentration tank 13 through the inorganic membrane concentrated water delivery pipe 12.

[0143] Step 8: Backwashing:

[0144] Step 8.1, backwashing of organic membrane filter:

[0145] When the difference between the inlet water pressure and the produced water pressure of the organic membrane filter 4 reaches the design upper limit, the organic membrane filter 4 is backwashed through the first backwash water tank 17, the first backwash pipe 18 and the first backwash water pump 19. The time for each backwash is 1 to 3 minutes, and the total backwash time is 0.5 to 4 hours. The concentrated water generated after the backwash is completed is discharged through the mud discharge pipe 44 of the organic membrane filter 4.

[0146] Step 8.2, backwashing of inorganic membrane filter:

[0147] When the difference between the inlet water pressure of the inorganic membrane filter 10 and the produced water pressure reaches the design upper limit, the inorganic membrane filter 10 is backwashed through the high-pressure gas delivery pipeline 20, the second backwash water tank 21 and the second backwash pipeline 22. During backwashing, the inlet pressure of the high-pressure gas is controlled at 2 to 6 bar, and the total backwashing time is 0.5 to 4 hours. The concentrated water generated after the backwashing is discharged through the mud discharge pipe 44 of the inorganic membrane filter 10.

[0148] Step nine, chemical cleaning:

[0149] Step 9.1, chemical cleaning of organic membrane filter:

[0150] When the organic membrane contamination of the organic membrane filter 4 reaches an irreversible level, first open the liquid outlet control valve 32 and the first cleaning liquid control valve 34 on the clean water tank outlet pipe 26 and start the cleaning pump 33. Driven by the cleaning pump 33, the water in the clean water tank 23 enters the organic membrane filter 4 through the clean water tank outlet pipe 26, the cleaning liquid delivery main pipe 29 and the cleaning liquid first delivery branch pipe 30, and the organic membrane filter 4 is washed for the first time. The time for the first water washing is 3 to 10 minutes.

[0151] After the first water washing is completed, the liquid outlet control valve 32 on the clean water tank outlet pipe 26 is closed, and the liquid outlet control valve 32 on the alkali washing tank outlet pipe 27 is opened. Under the drive of the cleaning pump 33, the alkali washing liquid in the alkali washing tank 24 enters the organic membrane filter 4 through the alkali washing tank outlet pipe 27, the cleaning liquid delivery main pipe 29 and the cleaning liquid first delivery branch pipe 30, and performs alkali washing on the organic membrane filter 4. The alkali washing time is 3 to 10 minutes; the alkali washing liquid is an aqueous solution of sodium hypochlorite and sodium hydroxide, and the mass fraction of sodium hypochlorite and sodium hydroxide is 0.1% to 1.5%.

[0152] After the alkali washing is completed, the liquid outlet control valve 32 on the alkali washing tank outlet pipe 27 is closed, and the liquid outlet control valve 32 on the clean water tank outlet pipe 26 is opened again to perform a second water washing, and the second water washing time is 2 to 5 minutes. After the second water washing is completed, the liquid outlet control valve 32 on the clean water tank outlet pipe 26 is closed, and the liquid outlet control valve 32 on the pickling tank outlet pipe 28 is opened. Under the drive of the cleaning pump 33, the pickling liquid in the pickling tank 25 enters the organic membrane filter 4 through the pickling tank outlet pipe 28, the cleaning liquid delivery main pipe 29 and the cleaning liquid first delivery branch pipe 30, and the organic membrane filter 4 is pickled for 3 to 10 minutes. The pickling liquid is an aqueous solution of citric acid, and the mass fraction of citric acid is 0.2% to 0.6%.

[0153] Step 9.2, chemical cleaning of inorganic membrane filter:

[0154] When the organic membrane contamination of the inorganic membrane filter 10 reaches an irreversible level, first open the liquid outlet control valve 32 and the cleaning liquid second control valve 35 on the clean water tank outlet pipe 26 and start the cleaning pump 33. Driven by the cleaning pump 33, the water in the clean water tank 23 enters the inorganic membrane filter 10 through the clean water tank outlet pipe 26, the cleaning liquid delivery main pipe 29 and the cleaning liquid second delivery branch pipe 31, and the inorganic membrane filter 10 is washed for the first time. The time for the first water washing is 3 to 10 minutes.

[0155] After the first water washing is completed, the liquid outlet control valve 32 on the clean water tank outlet pipe 26 is closed, and the liquid outlet control valve 32 on the alkali washing tank outlet pipe 27 is opened. Under the drive of the cleaning pump 33, the alkali washing liquid in the alkali washing tank 24 enters the inorganic membrane filter 10 through the alkali washing tank outlet pipe 27, the cleaning liquid delivery main pipe 29 and the cleaning liquid second delivery branch pipe 31, and the inorganic membrane filter 10 is alkali washed. The alkali washing time is 3 to 10 minutes; the alkali washing liquid is an aqueous solution of sodium hypochlorite and sodium hydroxide, and the mass fraction of sodium hypochlorite and sodium hydroxide is 0.1% to 1.5%.

[0156] After the alkali washing is completed, the liquid outlet control valve 32 on the alkali washing tank outlet pipe 27 is closed, and the liquid outlet control valve 32 on the clean water tank outlet pipe 26 is opened again to carry out a second water washing, and the second water washing time is 2 to 5 minutes; after the second water washing is completed, the liquid outlet control valve 32 on the clean water tank outlet pipe 26 is closed, and the liquid outlet control valve 32 on the pickling tank outlet pipe 28 is opened. Under the drive of the cleaning pump 33, the pickling liquid in the pickling tank 25 enters the inorganic membrane filter 10 through the pickling tank outlet pipe 28, the cleaning liquid delivery main pipe 29 and the cleaning liquid second delivery branch pipe 31, and the inorganic membrane filter 10 is pickled for 3 to 10 minutes; the pickling liquid is an aqueous solution of citric acid, and the mass fraction of citric acid is 0.2% to 0.6%.

[0157] Effect verification:

[0158] A series of influent suspended solids concentrations were taken: 100 mg / L, 500 mg / L, 1000 mg / L, 1500 mg / L, 2000 mg / L, 3000 mg / L, 4000 mg / L, and 5000 mg / L. Coal slime from the bottom of the regulating tank in the mine water treatment plant was added to the water. According to the above influent suspended solids concentrations, a series of solutions with different influent suspended solids concentrations were prepared and obtained to simulate mine water with influent suspended solids concentrations.

[0159] The service life of the organic membrane is calculated based on an average of 5 years, 20 hours a day, and 365 days of operation. In the actual coal mine water operation project, the unit membrane flux is 100 L / m 2·h calculation, unit price is 500 yuan / m 2 Calculate and obtain the cost of membrane materials for water treatment as RMB 0.14 / m 3 .

[0160] The simulation experiment was conducted using four organic membrane modules with a membrane area of ​​16 square meters. The water flux was about 6.4t / h and the design unit flux was 100 L / m 2 h, set the cross-flow multiple of the organic membrane filter to 2 (i.e., the concentrated water output of the organic membrane filter is twice the clean water output), the water output rate of the organic membrane filter is between 30% and 35%, run for 15 days, the backwash operating pressure is 0.1 MPa, and the raw water inlet flow rate is 100 t / h. The above series of values ​​of inlet suspended solids concentration and the corresponding operating costs of the organic membrane filter are as follows: Figure 2 and as shown in Table 1.

[0161] Table 1. Operating costs of organic membrane filters corresponding to different influent suspended solids concentration values

[0162]

[0163] The service life of inorganic membrane is calculated based on an average of 8 years, running 20 hours a day, 365 days a year. In the actual coal mine water operation project, the unit membrane flux is 200 L / m 2 ·h calculation, unit price is 5000 yuan / m 2 , it can be calculated that the cost of water treatment membrane materials is 0.43 yuan / m 3 .

[0164] The simulation experiment was conducted using an inorganic membrane module. A single membrane module consists of 61 membranes with an area of ​​0.55m 2 The tubular membrane has an average pore size of 40nm, a water production flux of 6.7t / h, and a designed unit flux of 200L / m2·h. Since the ceramic membrane equipment can tolerate high suspended solids, high cross-flow is not required. The cross-flow multiple of the inorganic membrane filter is set to 0.3 (that is, the concentrated water output of the inorganic membrane filter is 0.3 times the clean water output) and is run for 15 days. The operating pressure of the backwash is 0.1MPa, and the inlet flow rate of the raw water is 100t / h. The values ​​of the above series of inlet suspended solids concentration values ​​and the corresponding operating costs of the inorganic membrane filter are as follows: Figure 3 and as shown in Table 2.

[0165] Table 2. Operating costs of inorganic membrane filters corresponding to different influent suspended solids concentration values

[0166] Influent suspended solids concentration (mg / L) Suspended matter content of clean water from inorganic filter (mg / L) Total backwashing time (h) Energy consumption per ton of water (kW·h) Assuming electricity cost is 1 yuan / kWh, the operating cost of inorganic membrane filter (yuan / ton) Assuming the electricity fee is 0.5 yuan / kWh, the operating cost of the inorganic membrane filter (yuan / ton) 100 ＜1 4 0.19 0.62 0.525 500 ＜1 4 0.22 0.65 0.54 1000 ＜1 3 0.27 0.7 0.565 1500 ＜1 3 0.33 0.76 0.595 2000 ＜1 3 0.37 0.8 0.615 3000 ＜1 2 0.42 0.85 0.64 4000 ＜1 2 0.52 0.95 0.69 5000 ＜1 1 0.59 1.02 0.725

[0167] Depend on Figure 2 and Figure 3It can be seen that the operating cost of organic membrane filters is low at low suspended solids concentrations, while the operating cost of inorganic membrane filters is low at high suspended solids concentrations; in addition, the lower the electricity price, the wider the applicable concentration of the organic membrane filter.

[0168] To more intuitively demonstrate the advantages of combining organic and inorganic membrane filters compared to single-type filters, the system operating costs for two values ​​of suspended solids concentration in raw water are given here:

[0169] When the electricity fee is 1 yuan / kWh, according to the operating cost curve S1 of the influent suspended solids concentration-organic membrane filter and the operating cost curve S2 of the influent suspended solids concentration-inorganic membrane filter, it can be seen that the critical suspended solids concentration is 950 mg / L; the cross-flow multiple of the organic membrane filter is Take it as 2, and use formula I to calculate and obtain the suspended solids concentration in the regulating tank The suspended solids concentration in the intermediate water tank is 760 mg / L. Formula III is used to calculate and obtain the suspended solids concentration in the intermediate water tank. It is 1140 mg / L.

[0170] (A) The suspended solids concentration of raw water Take 300 mg / L, the cross-flow multiple of the organic membrane filter Take 2 as the output of clean water from the organic membrane filter Take 73.7t / h, critical suspended solids concentration is 950 mg / L, use formula V to calculate and obtain the amount of concentrated water entering the intermediate water tank The process flow obtained by calculating the above values ​​and using the steps of Example 2 is as follows: Figure 4 As shown by Figure 4 It can be seen that the average value of the influent suspended solids concentration of the two different membrane systems under this process is the critical influent suspended solids concentration. Compared with the operation of a single system, the operating cost of this hybrid membrane system is lower.

[0171] (B) The suspended solids concentration of raw water Take 600 mg / L, the cross-flow multiple of the organic membrane filter Take 2 as the output of clean water from the organic membrane filter Take 47.4t / h, critical suspended solids concentration is 950 mg / L, use formula V to calculate and obtain the amount of concentrated water entering the intermediate water tank The process flow obtained by using the above values ​​and the steps of Example 2 is as follows: Figure 5 As shown by Figure 5It can be seen that when the inlet suspended solids concentration is high, the less concentrated water returns to the regulating tank, and the greater the flow rate entering the intermediate water tank as the inlet water of the silicon carbide ceramic membrane. Since the number of membranes and components is fixed when the two systems are designed, the average inlet suspended solids concentration value within a certain period of time can be used as the design reference value of the inlet suspended solids concentration value.

Claims

1. A mine water inorganic membrane-organic membrane hybrid direct filtration purification method, characterized in that: The method adopts a mine water inorganic membrane-organic membrane hybrid direct filtration purification system; the method specifically comprises the following steps: Step 1: Obtain critical suspended solids concentration: Take a series of influent suspended solids concentration values, calculate the operating cost of the organic membrane filter corresponding to each influent suspended solids concentration value, then draw a scatter plot based on the calculation results and connect adjacent scatter plots with straight lines to obtain the influent suspended solids concentration value-organic membrane filter operating cost curve S1; calculate the operating cost of the inorganic membrane filter corresponding to each influent suspended solids concentration value, then draw a scatter plot based on the calculation results and connect adjacent scatter plots with straight lines to obtain the influent suspended solids concentration value-inorganic membrane filter operating cost curve S2; take the intersection of the influent suspended solids concentration value-organic membrane filter operating cost curve S1 and the influent suspended solids concentration value-inorganic membrane filter operating cost curve S2, and the influent suspended solids concentration value corresponding to the intersection is the critical suspended solids concentration X L The value of Step 2: Get the suspended solids concentration in the regulating tank: Substitute the cross-flow multiple of the organic membrane filter, the multiple of the clean water output of the organic membrane filter to its own output, and the critical suspended solids concentration obtained in step 1 into Formula I to calculate and obtain the suspended solids concentration in the regulating tank; Formula I is: Where: X0 represents the suspended solids concentration in the regulating tank; R S Indicates the cross-flow multiple of the organic membrane filter; R C It represents the multiple of the clean water output of the organic membrane filter to its own output, which is 1; Step 3: Obtain the expression for the suspended solids concentration in the intermediate water tank: Substitute the cross-flow multiple of the organic membrane filter, the multiple of the clean water output of the organic membrane filter to its own output, and the suspended solids concentration of the regulating tank obtained in step 2 into formula II to calculate and obtain the suspended solids concentration of the intermediate water tank; the formula II is: Where: X Z Indicates the suspended solids concentration in the intermediate water tank; Step 4: Get the amount of concentrated water entering the intermediate water tank: Substitute Formula I from Step 2 into Formula II from Step 3 to obtain Formula III for the suspended solids concentration in the intermediate water tank; assume that the suspended solids concentration of the raw water and the initial suspended solids concentration in the intermediate water tank are equal to obtain Formula IV; then substitute Formula III into Formula IV to obtain Formula V; then substitute the suspended solids concentration of the raw water, the amount of water entering the organic membrane filter, the clean water output of the organic membrane filter, and the critical suspended solids concentration value from Step 1 into Formula V to calculate and obtain the multiple of the amount of brine entering the intermediate water tank to the clean water output of the organic membrane filter; and multiply this multiple by the clean water output of the organic membrane filter to obtain the amount of brine entering the intermediate water tank; The formula III is: The formula IV is: Where: X R Indicates the suspended solids concentration of raw water; R Z Indicates the multiple of the concentrated water volume entering the intermediate water tank to the clean water output of the organic membrane filter; The formula V is: Step 5: Obtain the amount of concentrated water returned to the regulating tank: Substitute the cross-flow multiple of the organic membrane filter and the multiple of the amount of brine entering the intermediate water tank obtained in step 4 to the clean water output of the organic membrane filter into formula VI to calculate and obtain the multiple of the amount of brine returned to the regulating tank to the clean water output of the organic membrane filter. Multiply this multiple by the clean water output of the organic membrane filter to obtain the amount of brine returned to the regulating tank. The formula VI is: R H =R S -R Z Formula VI; Where: R H Indicates the multiple of the concentrated water volume returned to the regulating tank to the clean water output of the organic membrane filter; The inorganic membrane-organic membrane hybrid direct filtration purification system for mine water comprises a mine water inlet pipe (1), the outlet end of the mine water inlet pipe (1) is connected to the first inlet end of the regulating tank (2), the first outlet end of the regulating tank (2) is connected to the inlet end of the preliminary filtration pipe (3), the first outlet end of the preliminary filtration pipe (3) is connected to the first inlet end of the organic membrane filter (4), the first outlet end of the organic membrane filter (4) is connected to the organic membrane water production pipe (5); the second outlet end of the organic membrane filter (4) is connected to the inlet end of the organic membrane concentrated water delivery pipe (6), the first outlet end of the organic membrane concentrated water delivery pipe (6) is connected to the inlet end of the intermediate water tank (7); the second outlet end of the organic membrane concentrated water delivery pipe (6) is connected to the inlet end of the organic membrane concentrated water return pipe (8), and the outlet end of the organic membrane concentrated water return pipe (8) is connected to the second inlet end of the regulating tank (2); The water outlet end of the intermediate water tank (7) is connected to the water inlet end of the transition conveying pipe (9), the water outlet end of the transition conveying pipe (9) is connected to the water inlet end of the inorganic membrane filter (10), the first water outlet end of the inorganic membrane filter (10) is connected to the inorganic membrane water production pipe (11), the second water outlet end of the inorganic membrane filter (10) is connected to the water inlet end of the inorganic membrane concentrated water conveying pipe (12), and the water outlet end of the inorganic membrane concentrated water conveying pipe (12) is connected to the coal slime concentration tank (13); The preliminary filtration pipeline (3) is provided with a constant flow pump (14), the organic membrane concentrated water delivery pipeline (6) is provided with an intermediate water tank inlet regulating valve (15), and the organic membrane concentrated water return pipeline (8) is provided with an organic membrane concentrated water cross-flow valve (16).

2. The mine water inorganic membrane-organic membrane hybrid direct filtration purification method according to claim 1, characterized in that: The method further includes step 6, wherein the step 6 specifically includes the following process: Start the mine water inorganic membrane-organic membrane hybrid direct filtration purification system, adjust the intermediate water tank inlet regulating valve (15) to control the amount of concentrated water entering the intermediate water tank, so that the amount of concentrated water entering the intermediate water tank reaches the value calculated in step four; adjust the organic membrane concentrated water cross-flow valve (16) to control the amount of concentrated water returning to the regulating tank, so that the amount of concentrated water returning to the regulating tank reaches the value calculated in step five.

3. The mine water inorganic membrane-organic membrane hybrid direct filtration purification method according to claim 2, characterized in that: The process also includes step seven, wherein the step seven specifically includes the following process: After completing the water volume adjustment in step six, the system is officially put into operation. The mine water first enters the regulating tank (2) for sedimentation, then flows into the preliminary filtration pipe (3) and then enters the organic membrane filter (4) driven by the constant flow pump (14). The clean water produced by the organic membrane filter (4) flows into the organic membrane water production pipe (5). The concentrated water produced by the organic membrane filter (4) enters the inorganic membrane filter (10). The clean water produced by the inorganic membrane filter (10) flows into the inorganic membrane water production pipe (11). The concentrated water produced by the inorganic membrane filter (10) flows into the coal slime concentration tank (13) through the inorganic membrane concentrated water delivery pipe (12).

4. The mine water inorganic membrane-organic membrane hybrid direct filtration purification method according to claim 3, characterized in that: The inorganic membrane-organic membrane hybrid direct filtration purification system for mine water further comprises a first backwash water tank (17), the water outlet of the first backwash water tank (17) is connected to the water inlet of a first backwash pipe (18), the water outlet of the first backwash pipe (18) is connected to the second water inlet of the organic membrane filter (4), and a first backwash water pump (19) is provided on the first backwash pipe (18); The inorganic membrane-organic membrane hybrid direct filtration purification system for mine water further comprises a high-pressure gas delivery pipeline (20), the gas outlet end of the high-pressure gas delivery pipeline (20) is connected to the gas inlet end of the second backwash water tank (21), the water gas outlet end of the second backwash water tank (21) is connected to the water gas inlet end of the second backwash pipeline (22), and the water gas outlet end of the second backwash pipeline (22) is connected to the water gas inlet end of the inorganic membrane filter (10); The method further includes step eight; said step eight specifically includes the following steps: Step 8.1, backwashing of organic membrane filter: When the difference between the water inlet pressure and the water production side pressure of the organic membrane filter (4) reaches the design upper limit, the organic membrane filter (4) is backwashed through the first backwash water tank (17), the first backwash pipe (18) and the first backwash water pump (19), and the concentrated water generated after the backwash is discharged through the mud discharge pipe (44) of the organic membrane filter (4); Step 8.2, backwashing of inorganic membrane filter: When the difference between the water inlet pressure and the water production side pressure of the inorganic membrane filter (10) reaches the design upper limit, the inorganic membrane filter (10) is backwashed through the high-pressure gas delivery pipeline (20), the second backwash water tank (21) and the second backwash pipeline (22), and the concentrated water generated after the backwash is discharged through the mud discharge pipe (44) of the inorganic membrane filter (10).

5. The mine water inorganic membrane-organic membrane hybrid direct filtration purification method according to claim 4, characterized in that: In step 8.1, the backwashing time for each time is 1 to 3 minutes, and the total backwashing time is 0.5 to 4 hours.

6. The mine water inorganic membrane-organic membrane hybrid direct filtration purification method according to claim 4, characterized in that: In step 8.2, the inlet pressure of the high-pressure gas is controlled at 2 to 6 bar during backwashing, and the total backwashing time is 0.5 to 4 hours.

7. The mine water inorganic membrane-organic membrane hybrid direct filtration purification method according to claim 4, characterized in that: The inorganic membrane-organic membrane hybrid direct filtration purification system for mine water also includes a clean water tank (23), an alkali washing tank (24) and an acid washing tank (25); the water outlet end of the clean water tank (23) is connected to the water inlet end of the clean water tank outlet pipe (26), the water outlet end of the alkali washing tank (24) is connected to the water inlet end of the alkali washing tank outlet pipe (27), and the water outlet end of the acid washing tank (25) is connected to the water inlet end of the acid washing tank outlet pipe (28); the clean water tank outlet pipe (26), the alkali washing tank outlet pipe (27) and the acid washing tank outlet pipe are connected. The water outlet ends of the pipeline (28) are connected to the water inlet end of the cleaning liquid delivery main pipeline (29), the first water outlet end of the cleaning liquid delivery main pipeline (29) is connected to the water inlet end of the cleaning liquid delivery branch pipeline (30), the water outlet end of the cleaning liquid delivery branch pipeline (30) is connected to the preliminary filtering pipeline (3), the second water outlet end of the cleaning liquid delivery main pipeline (29) is connected to the water inlet end of the cleaning liquid delivery branch pipeline (31), and the water outlet end of the cleaning liquid delivery branch pipeline (31) is connected to the transition delivery pipeline (9); The clean water tank outlet pipe (26), the alkali cleaning tank outlet pipe (27) and the acid cleaning tank outlet pipe (28) are respectively provided with a liquid outlet control valve (32); the cleaning liquid delivery main pipe (29) is provided with a cleaning pump (33); the cleaning liquid first delivery branch pipe (30) is provided with a cleaning liquid first control valve (34); and the cleaning liquid second delivery branch pipe (31) is provided with a cleaning liquid second control valve (35); The method further includes step nine; said step nine specifically includes the following steps: Step 9.1, chemical cleaning of organic membrane filter: When the organic membrane of the organic membrane filter (4) is contaminated to an irreversible degree, the liquid outlet control valve (32) and the first cleaning liquid control valve (34) on the clean water tank outlet pipe (26) are first opened and the cleaning pump (33) is started. Under the drive of the cleaning pump (33), the water in the clean water tank (23) enters the organic membrane filter (4) through the clean water tank outlet pipe (26), the cleaning liquid delivery main pipe (29) and the cleaning liquid delivery branch pipe (30), thereby performing a first water washing on the organic membrane filter (4); After the first water washing is completed, the liquid outlet control valve (32) on the clean water tank outlet pipe (26) is closed, and the liquid outlet control valve (32) on the alkali washing tank outlet pipe (27) is opened. Under the drive of the cleaning pump (33), the alkali washing liquid in the alkali washing tank (24) enters the organic membrane filter (4) through the alkali washing tank outlet pipe (27), the cleaning liquid delivery main pipe (29) and the cleaning liquid first delivery branch pipe (30), thereby performing alkali washing on the organic membrane filter (4); After the alkali washing is completed, the liquid outlet control valve (32) on the alkali washing tank outlet pipe (27) is closed, and the liquid outlet control valve (32) on the clean water tank outlet pipe (26) is opened again to perform a second water washing, and the second water washing time is 2 to 5 minutes; after the second water washing is completed, the liquid outlet control valve (32) on the clean water tank outlet pipe (26) is closed, and the liquid outlet control valve (32) on the acid washing tank outlet pipe (28) is opened. Under the drive of the cleaning pump (33), the pickling liquid in the pickling tank (25) enters the organic membrane filter (4) through the pickling tank outlet pipe (28), the cleaning liquid delivery main pipe (29) and the cleaning liquid first delivery branch pipe (30), and the organic membrane filter (4) is pickled; Step 9.2, chemical cleaning of inorganic membrane filter: When the inorganic membrane of the inorganic membrane filter (10) is contaminated to an irreversible degree, the liquid outlet control valve (32) and the cleaning liquid second control valve (35) on the clean water tank outlet pipe (26) are first opened and the cleaning pump (33) is started. Under the drive of the cleaning pump (33), the water in the clean water tank (23) enters the inorganic membrane filter (10) through the clean water tank outlet pipe (26), the cleaning liquid delivery main pipe (29) and the cleaning liquid delivery branch pipe (31), thereby performing the first water washing on the inorganic membrane filter (10); After the first water washing is completed, the liquid outlet control valve (32) on the clean water tank outlet pipe (26) is closed, and the liquid outlet control valve (32) on the alkali washing tank outlet pipe (27) is opened. Under the drive of the cleaning pump (33), the alkali washing liquid in the alkali washing tank (24) enters the inorganic membrane filter (10) through the alkali washing tank outlet pipe (27), the cleaning liquid delivery main pipe (29) and the cleaning liquid second delivery branch pipe (31), thereby performing alkali washing on the inorganic membrane filter (10); After the alkali washing is completed, the liquid outlet control valve (32) on the alkali washing tank outlet pipe (27) is closed, and the liquid outlet control valve (32) on the clean water tank outlet pipe (26) is opened again to perform a second water washing, and the second water washing time is 2 to 5 minutes; after the second water washing is completed, the liquid outlet control valve (32) on the clean water tank outlet pipe (26) is closed, and the liquid outlet control valve (32) on the acid washing tank outlet pipe (28) is opened. Under the drive of the cleaning pump (33), the pickling liquid in the pickling tank (25) enters the inorganic membrane filter (10) through the pickling tank outlet pipe (28), the cleaning liquid delivery main pipe (29) and the cleaning liquid second delivery branch pipe (31), and the inorganic membrane filter (10) is pickled.

8. The mine water inorganic membrane-organic membrane hybrid direct filtration purification method according to claim 7, characterized in that: In steps 9.1 and 9.2, the first water washing time is 3 to 10 minutes.

9. The method for purifying mine water by inorganic membrane-organic membrane hybrid direct filtration according to claim 7, characterized in that: In steps 9.1 and 9.2, the alkaline washing time is 3 to 10 minutes; the alkaline washing solution is an aqueous solution of sodium hypochlorite and sodium hydroxide, and the mass fraction of sodium hypochlorite and sodium hydroxide is 0.1% to 1.5%.

10. The method for purifying mine water by inorganic membrane-organic membrane hybrid direct filtration according to claim 7, characterized in that: In steps 9.1 and 9.2, the pickling time is 3 to 10 minutes; the pickling solution is an aqueous solution of citric acid, and the mass fraction of citric acid is 0.2% to 0.6%.

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