Device and method for advanced water treatment

Abstract

Disclosed are a device and a method for advanced water treatment, and the device comprises a plate-and-frame membrane reactor having a water inlet pipe and a water outlet pipe, a raw water delivery system communicating with the water inlet pipe of the plate-and-frame membrane reactor, and a clear water reservoir communicating with the water outlet pipe of the plate-and-frame membrane reactor; the advanced water treatment device further comprises an oxidant dosing system communicating with the water inlet pipe of the plate-and-frame membrane reactor or the raw water delivery system, the plate-and-frame membrane reactor further comprises a carbon nano-material composite membrane, the carbon nano-material composite membrane comprises carbon nano-material layers sequentially disposed between the water inlet pipe and the water outlet pipe, and a base membrane layer supporting the carbon nano-material layers, and the raw material of the carbon nano-material layers comprises mono-layer reduced graphene oxide and multiwalled carbon nanotubes.

Claims

1. An advanced water treatment device, comprising: a plate-and-frame membrane module having a water inlet pipe and a water outlet pipe, the late-and-frame membrane module comprising: a thrust plate disposed at a first end of the plate-and-frame membrane module; a pressing plate disposed at a second end of the plate-and-frame membrane module, the second end opposing the first end; a front partition plate directly adjacent to the thrust plate, located between the first end and the second end; a rear partition plate directly adjacent to the pressing plate, located between the first end and the second end; a plurality of filter plates located between the front partition plate and the rear partition plate; a plurality of middle partition plates, which are different than the plurality of filter plates, located between the front partition plate and the rear partition plate; wherein, between the front partition plate and the rear partition plate, the plurality of middle partition plates are disposed between two adjacent filter plates so that each filter plate is directly adjacent to a middle partition plate; wherein a flow guide screen plate and an orifice plate are disposed between each filter plate and middle partition plate arranged between the front partition plate and the rear partition plate; wherein the water outlet pipe extends through an upper portion of the front partition plate, an upper portion of the plurality of filter plates, an upper portion of the plurality of middle partition plates, and an upper portion of the rear partition plate; wherein the water inlet pipe extends through a bottom portion of the front partition plate, a bottom portion of the plurality of filter plates, a bottom portion of the plurality of middle partition plates, and a bottom portion of the rear partition plate; a raw water delivery system communicating with the water inlet pipe of the plate-and-frame membrane module a clear water reservoir communicating with the water outlet pipe of the plate-and-frame membrane module; and an oxidant dosing system communicating with the water inlet pipe of the plate-and-frame membrane module or the raw water delivery system; wherein the plate-and-frame membrane module further comprises one or more carbon nanomaterial composite membranes, the one or more carbon nanomaterial composite membranes comprise carbon nanomaterial layers and base membrane layers supporting the carbon nanomaterial layers which are sequentially disposed between the water inlet pipe and the water outlet pipe, and raw materials of the carbon nanomaterial layers comprise mono-layer reduced graphene oxide and multiwalled carbon nanotubes, a mass ratio of the reduced graphene oxide to the multiwalled carbon nanotubes in the carbon nanomaterial layer is (2-4):1; wherein a loading amount of the carbon nanomaterial layers on surfaces of the base membrane layers in each of the one or more carbon nanomaterial composite membranes is 8-32 g/m.sup.2, the loading amount being a mass of the carbon nanomaterial layer supported on a surface of a base membrane layer per unit area; wherein the raw water delivery system is used to store raw water to be treated, in the raw water to be treated, a concentration of organic micro-pollutants is below 0.5 mg/L, a total organic carbon concentration is less than 1 mg/L, there is no suspended matter, and pH is 6-9; wherein the oxidant dosing system is used to store oxidant; wherein a mixed liquid of the raw water to be treated and the oxidant zigzags in a microlayer structure of the one or more carbon nanomaterial composite membranes, and at the same time, a catalytic oxidation and a separation and retainment happen, thus the organic micro-pollutants in the raw water to be treated are effectively removed.

2. The advanced water treatment device according to claim 1, wherein the flow guide screen plate is disposed between the water inlet pipe and the carbon nanomaterial layer, and a silica gel seal ring is disposed between the flow guide screen plate and the carbon nanomaterial layer.

3. The advanced water treatment device according to claim 2, wherein the orifice plate comprises a base plate, a plurality of flow guide trenches provided on the base plate, and a plurality of flow guide holes provided in the flow guide trenches.

4. The advanced water treatment device according to claim 2, wherein one flow guide screen plate, one silica gel seal ring, one carbon nanomaterial composite membrane and one orifice plate form a membrane separation assembly, and the plate-and-frame membrane module comprises a plurality of membrane separation assemblies arranged side by side.

5. The advanced water treatment device according to claim 4, wherein the front partition plate, the plurality of middle partition plates, the rear partition plate and the plurality of filter plates respectively have internal cavities, and a side of the front partition plate close to the plurality of filter plates and a side of the rear partition plate close to the plurality of filter plates are respectively provided with an opening communicating with the internal cavities, and both sides of the plurality of middle partition plates and both sides of the plurality of filter plates are provided with openings communicating with the internal cavities; the lower portions of the front partition plate, the plurality of middle partition plates and the rear partition plate respectively connect the internal cavities with the water inlet pipe via first communicating pipes; and the upper portions of the plurality of filter plates connect the internal cavities with the water outlet pipe via second communicating pipes.

6. The advanced water treatment device according to claim 5, wherein a cross-sectional area of the internal cavities is the same as the filtration area of each of the carbon nanomaterial composite membranes; dimensions of the front partition plate, the plurality of middle partition plates and the rear partition plate are the same, and a thickness of the plurality of filter plates is 1.2 to 1.5 times a thickness of the plurality of middle partition plates.

7. The advanced water treatment device according to claim 1, wherein the raw water delivery system comprises a raw water tank, a first pipeline communicating with the raw water tank, a pressure pump communicating with the first pipeline, a second pipeline respectively communicating with the pressure pump and the water inlet pipe, a first valve and a first flow meter arranged on the first pipeline, and a second valve arranged on the second pipeline; the oxidant dosing system comprises an oxidant storage tank, a third pipeline communicating with the oxidant storage tank, a dosing pump communicating with the third pipeline, a fourth pipeline respectively communicating with the dosing pump and the first pipeline, a third valve arranged on the third pipeline, and a second flow meter arranged on the fourth pipeline.

8. The advanced water treatment device according to claim 1, further comprising a pressure gauge arranged on the water inlet pipe.

9. The advanced water treatment device according to claim 1, wherein the advanced water treatment device further comprises a membrane function regeneration system, and the membrane function regeneration system comprises an ammonia stirring and sealed storage tank, a fifth pipeline communicating with the ammonia stirring and sealed storage tank, a circulating water pump communicating with the fifth pipeline, a sixth pipeline communicating with the circulating water pump, a heat exchanger communicating with the sixth pipeline, a seventh pipeline respectively communicating with the heat exchanger and the water inlet pipe, an eighth pipeline respectively communicating with the water outlet pipe and a bottom portion of the ammonia stirring and sealed storage tank, a fourth valve and a third flow meter arranged on the fifth pipeline, a fifth valve arranged on the seventh pipeline, and a sixth valve arranged on the eighth pipeline; and/or, the advanced water treatment device further comprises a seventh valve arranged on the water outlet pipe between the junction of the eighth pipeline and the water outlet pipe and the clean water reservoir.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) For more clearly explaining the technical solutions in the embodiments of the present disclosure or the prior art, the accompanying drawings used to describe the embodiments or the prior art are simply introduced in the following. Apparently, the below described drawings merely show a part of the embodiments of the present disclosure, and those skilled in the art can obtain other drawings according to the accompanying drawings without creative work.

(2) FIG. 1 is a schematic structure diagram of an advanced water treatment device in a specific implementation;

(3) FIG. 2 is an electronic picture of a carbon nano-material composite membrane;

(4) FIG. 3 is a scanning electron microscope picture of a carbon nano-material layer;

(5) FIG. 4 is a cross-section diagram of a plate-and-frame membrane module in a specific implementation;

(6) FIG. 5 is a side view of a middle partition plate in a specific implementation;

(7) FIG. 6 is a side view of a filter plate in a specific implementation;

(8) FIG. 7 is a side view of a flow guide screen plate in a specific implementation;

(9) FIG. 8 is a side view of an orifice plate in a specific implementation;

(10) FIG. 9 is a diagram showing the relationship between the removal rate of low-concentration sulfamethoxazole and the single running time of the advanced water treatment device in Embodiment 1;

(11) FIG. 10 is a diagram showing the relationship between the removal rate of low-concentration sulfamethoxazole and the regeneration times of the advanced water treatment device in Embodiment 1;

(12) FIG. 11 is a diagram showing the relationship between the removal rate of low-concentration phenols and the single running time of the advanced water treatment device in Embodiment 2;

(13) FIG. 12 is a diagram showing the relationship between the removal rate of low-concentration phenols and the regeneration times of the advanced water treatment device in Embodiment 2;

(14) wherein, 1—plate-and-frame membrane module; 2—clean water reservoir; 3—seventh valve; 4—pressure gauge; 11—thrust plate; 12—front partition plate; 13—filter plate; 14—silica gel seal ring; 15—flow guide screen plate; 16—carbon nano-material composite membrane; 17—orifice plate; 18—middle partition plate; 19—rear partition plate; 20—pressing plate; 21—water inlet pipe; 22—water outlet pipe; 23—tight plate; 24—fastener; 25—internal cavity; 26—first communicating pipe; 27—second communicating pipe; 31—raw water tank; 32—first pipeline; 33—pressure pump; 34—second pipeline; 35—first valve; 36—first flow meter; 37—second valve; 41—oxidant storage tank; 42—third pipeline; 43—dosing pump; 44—fourth pipeline; 45—third valve; 46—second flow meter; 51—ammonia stirring and sealed storage tank; 52—fifth pipeline; 53—circulating water pump; 54—sixth pipeline; 55—heat exchanger; 56—seventh pipeline; 57—eighth pipeline; 58—fourth valve; 59—third flow meter; 60—fifth valve; 61—sixth valve; 171—base plate; 172—flow guide trench; 173—flow guide hole.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

(15) In the following, the present disclosure is further explained in detail combining with the accompanying drawings and specific embodiments, but the present disclosure is not limited to the following embodiments. The specific experimental methods that are not indicated in the embodiments are carried out in accordance with the national standard methods and conditions.

(16) An advanced water treatment device as shown in FIG. 1 comprises a plate-and-frame membrane module 1, a raw water delivery system, an oxidant dosing system, a membrane function regeneration system, a clear water reservoir 2, and the like. The raw water delivery system and the oxidant dosing system are connected via pipelines, and are connected to a water inlet pipe 21 of the plate-and-frame membrane module 1 after being connected with the membrane function regeneration system in parallel, and a water inlet pipe 21 of the plate-and-frame membrane module 1 is connected to the clear water reservoir 2.

(17) The raw water delivery system comprises a raw water tank 31, a first pipeline 32 communicating with the raw water tank 31, a pressure pump 33 communicating with the first pipeline 32, a second pipeline 34 respectively communicating with the pressure pump 33 and the water inlet pipe 21, a first valve 35 and a first flow meter 36 arranged on the first pipeline 32, and a second valve 37 arranged on the second pipeline 34. The first flow meter 36 is located between the first valve 35 and the pressure pump 33.

(18) The oxidant dosing system comprises an oxidant storage tank 41, a third pipeline 42 communicating with the oxidant storage tank 41, a dosing pump 43 communicating with the third pipeline 42, a fourth pipeline 44 respectively communicating with the dosing pump 43 and the first pipeline 32, a third valve 45 arranged on the third pipeline 42, and a second flow meter 46 arranged on the fourth pipeline 44. The oxidant dosed by the oxidant dosing system is a persulfate solution or an ozone aqueous solution.

(19) The junction of the fourth pipeline 44 and the first pipeline 32 is located between the first flow meter 36 and the pressure pump 33. The raw water from the first pipeline 32 and the oxidant from the fourth pipeline 44 run into the pressure pump 33, and after being pressurized by the pressure pump 33, run into the water inlet pipe 21 via the second pipeline 34.

(20) The membrane function regeneration system comprises an ammonia stirring and sealed storage tank 51, a fifth pipeline 52 communicating with the ammonia stirring and sealed storage tank 51, a circulating water pump 53 communicating with the fifth pipeline 52, a sixth pipeline 54 communicating with the circulating water pump 53, a heat exchanger 55 communicating with the sixth pipeline 54, a seventh pipeline 56 respectively communicating with the heat exchanger 55 and the water inlet pipe 21, an eighth pipeline 57 respectively communicating with the water outlet pipe 22 and a bottom portion of the ammonia stirring and sealed storage tank 51, a fourth valve 58 and a third flow meter 59 arranged on the fifth pipeline 52, a fifth valve 60 arranged on the seventh pipeline 56, and a sixth valve 61 arranged on the eighth pipeline 57. The third flow meter 59 is located between the fourth valve 58 and the circulating water pump 53. Wherein, the flow direction of the heat source (such as hot water, hot air, hot oil) of the heat exchanger 55 is opposite to the flow direction of the ammonia so as to facilitate the heating of the ammonia.

(21) The advanced water treatment device further comprises a seventh valve 3 arranged on the water outlet pipe 22 between the junction of the eighth pipeline 57 and the water outlet pipe 22 and the clean water reservoir 2.

(22) The advanced water treatment device further comprises a pressure gauge 4 arranged on the water inlet pipe 21. The raw water and the oxidant run into the plate-and-frame membrance module 1 through the pressure gauge 4 after being pressurized by the pressure pump 33, and the ammonia run into the plate-and-frame membrane module 1 through the pressure gauge 4 after being heated by the heat exchanger 55.

(23) The raw water tank 31, the oxidant storage tank 41 and the ammonia stirring and sealed storage tank 51 are respectively provided with stirrers.

(24) The water inlet pipe 21, the water outlet pipe 22, the first pipeline 32, the second pipeline 34, the third pipeline 42, the fourth pipeline 44, the fifth pipeline 52, the sixth pipeline 54, the seventh pipeline 56, and the eighth pipeline 57 are all used 304 stainless steel pipe.

(25) As shown in FIG. 4, the plate-and-frame membrane module 1 comprises one thrust plate 1, one front partition plate 12, a plurality of filter plates 13, a plurality of silica gel seal rings 14, a plurality of flow guide screen plates 15, a plurality of carbon nano-material composite membranes 16, a plurality of orifice plates 17, a plurality of middle partition plates 18, one rear partition plate 19, one pressing plate 20, one water inlet pipe 21, one water outlet pipe 22, one tight plate 23 and one fastener 24.

(26) The thrust plate 11 is placed at the front end, followed by the front partition plate 12, and then the filter plates 13 (made of 304 stainless steel) and the middle partition plates 18 (made of 304 stainless steel) are placed alternately, and the rear partition plate 19 is placed behind the last filter plate 13, and the pressing plate 20, the tight plate 23 and the fastener 24 fix the components to ensure sealing.

(27) The water inlet pipe 21 and the water outlet pipe 22 are respectively arranged at the lower and upper portions of the plate-and-frame membrane module 1 and pass through the entire reactor.

(28) The front partition plate 12 and the rear partition plate 19 are respectively provided with an internal cavity 25 with a circular cross-section (the cross-sectional area of the internal cavity 25=the filtration area of the carbon nano-material composite membrane 16), and the sides adjacent to the filter plates 13 are respectively provided with an opening communicating with the internal cavities 25 and covered with the flow guide screen plate 15, and the other sides thereof are closed, and at the lower end the internal cavities 25 are communicated with the water inlet pipe 21 through the first communicating pipe 26.

(29) As shown in FIG. 5, the appearance and cavity size of the middle partition plates 18 are the same as that of the front partition plate 12 and the rear partition plate 19, while both sides of the middle partition plates 18 are respectively provided with an opening communicating with the internal cavities 25 and covered with the flow guide screen plate 15, and at the lower end the internal cavities 25 are communicated with the water inlet pipe 21 through the first communicating pipe 26.

(30) As shown in FIG. 6, the thickness of the filter plates 13 is 1.5 times the thickness of the middle partition plates 18, the filter plates 13 are respectively provided with an internal cavity 25 with a circular cross-section (the cross-sectional area of the internal cavity 25=the filtration area of the carbon nano-material composite membrane 16), and both sides of the filter plates 13 are respectively provided with an opening communicating with the internal cavities 25 and covered with the orifice plate 17, and at the upper end the internal cavities 25 are communicated with the water outlet pipe 22 through the second communicating pipe 27.

(31) As shown in FIG. 8, the orifice plate 17 comprises a base plate 171, a plurality of flow guide trenches 172 provided on the base plate 171, a plurality of flow guide holes 173 provided in each flow guide trench 172, and the flow guide trenches 172 are annular to facilitate the collection of filtrate. The carbon nano-material composite membranes 16 are placed on the orifice plates 17, and the flow guide screen plates 15 are inlaid with the silica gel seal rings 14 (as shown in FIG. 7), and the silica gel seal rings 14 are located between the flow guide screen plates 15 and the carbon nano-material composite membranes 16, and the carbon nano-material composite membranes 16 are located between the flow guide screen plates 15 and the orifice plates 17. When the respective components are fixed and pressed tightly, one flow guide screen plate 15, one silica gel seal ring 14, one carbon nano-material composite membrane 16 and one orifice plate 17 form a membrane separation assembly, so that multiple membrane separation assemblies are side by side arranged in the plate-and-frame membrane module 1.

(32) The carbon nanomaterial composite membranes 16 are prepared by uniformly loading reduced graphene oxide (rGO) and multiwalled carbon nanotubes (MWCNT) on the surfaces of base membranes at a mass ratio of (2-4):1, thereby forming carbon nano-material layers composed of reduced graphite oxide (rGO) and multiwalled carbon nanotubes (MWCNT) and base membrane layers, wherein an electronic picture of the carbon nano-material composite membranes 16 is shown in FIG. 2, and a scanning electron microscope picture of the carbon nano-material layers is shown in FIG. 3. Wherein, the carbon nano-material layers are located between the flow guide screen plates 15 and the base membrane layers, so that the mixture coming in from the water inlet pipe 21 enters the front partition plate 12, the plurality of middle partition plates 18, and the rear partition plate 19 through the first communicating pipe 26, and in the bottom-up flow process, is evenly distributed to the surfaces of the carbon nano-material layers after being guided by the flow guide screen plates 15; the mixture zigzags in the micro layer structure of the carbon nano-material composite membranes 16, and simultaneously undergoes catalytic oxidation and separation and retainment, which effectively removes organic micro-pollutants in water, after the treated water is collected by the orifice plates 17, it flows to the internal cavities 25 of the plurality of filter plates 13, and then runs into the water outlet pipe 22 through the second communicating pipe 27, and is transported to the clean water reservoir 2 by the water outlet pipe 22.

(33) The reduced graphene oxide is in a flake shape, with a diameter of 2-5 μm, a thickness of 0.8-1.2 nm, an atomic ratio of carbon to oxygen of (3-4):1, and a mono-layer rate of >95%. Wherein, the reduced graphene oxide is prepared by taking commercially purchased graphene oxide as raw material, obtaining an graphene oxide dispersion liquid by ultrasonic-assisted dispersion method, wherein the ultrasonic power density is 4-6 W.Math.mL.sup.−1, and the ultrasonic time is 20-30 min, and then adjusting pH to >10 by adding an ammonia solution with a mass fraction of 10%, and heated under confinement at 120° C. for 3-4 h. The multiwalled carbon nanotubes have an inner diameter of 2-5 nm, an outer diameter of <8 nm, a length of 1-2 μm, and a specific surface area of >500 m.sup.2/g. The base membrane of the base membrane layer is selected from the group consisting of a nylon membrane, poly(vinylidene fluoride) membrane, a hydrophilic modified polytetrafluoroethylene membrane, and combinations thereof; a filter pore diameter of the base membrane is below 0.45 μm.

(34) The loading amount of the carbon nano-material layer on the surfaces of the base membrane layers in the carbon nano-material composite membranes 16 is 8-32 g/m.sup.2, the pure water flux of the carbon nano-material composite membranes 16 is 30-90 L.Math.(m.sup.2.Math.h.Math.bar).sup.−1, the specific resistance is 1.0-2.0×10.sup.18 m.sup.−2, and the filtration area is not less than 0.1 m.sup.2.

(35) A water treatment method utilizing the above device comprises the following steps: (1) closing the fourth valve 58, the fifth valve 60, the sixth valve 61 and the circulating water pump 53, and opening the first valve 35, the second valve 37, the second valve 45, the seventh valve 3, the dosing pump 43 and the pressure pump 33; (2) storing the raw water to be treated in the raw water tank 31, stirring it by a stirrer to maintain a homogeneous state, and then transporting to the pressure pump 33 through the first pipeline 32, adjusting the first valve 35 to control the flow rate of the raw water, and controlling the flow rate of the raw water to be treated corresponds to a membrane flux of 0.5-5.0 L.Math.min.sup.−1.Math.m.sup.−2; (3) storing the oxidant in the oxidant storage tank 41, covering the oxidant storage tank 41, stirring it by a stirrer to maintain a homogeneous state, transporting the oxidant to the dosing pump 43 through the third pipeline 42 and then through the fourth pipeline 44 to the first pipeline 32 to mix up with the raw water in the first pipeline 32 and run into the pressure pump 33, adjusting the rotation speed of the dosing pump 43 to control the dosage of the oxidant, and controlling the flow rate of the oxidant to be not greater than 5% of the flow rate of the raw water to be treated; when the oxidant is a persulfate solution, controlling the temperature of the oxidant to be lower than 30° C.; when the oxidant is an ozone solution, controlling the temperature of the oxidant to be 0-4° C.; (4) transporting the mixture of the raw water and the oxidant through the second pipeline 34 to the water inlet pipe 21 of the plate-and-frame membrane module 1 after being pressurized by the pressure pump 33, when the oxidant is a persulfate solution, an initial molar concentration ratio of persulfate to organic micro-pollutants in the mixture is controlled to be (50-200):1; when the oxidant is an ozone solution, an initial mass concentration ratio of ozone to organic micro-pollutants in the mixture is controlled to be (10-50):1; (5) evenly distributing the mixture from the water inlet pipe 21 to the internal cavities of the front partition plate 12, the middle partition plates 18 and the rear partition plate 19 through the first communicating pipe 26, and in the bottom-up flow process, evenly distributing it to the surfaces of the carbon nano-material layers after being guided by the flow guide screen plates 15, the mixture zigzags in the micro layer structure of the carbon nano-material composite membranes 16, and simultaneously undergoing catalytic oxidation and separation and retainment, which effectively removes organic micro-pollutants in water, after collecting the treated water by the orifice plates 17, converging it to the internal cavities 25 of the filter plates 13, and then running into the water outlet pipe 22 through the second communicating pipe 27, and transporting it to the clean water reservoir 2 by the water outlet pipe 22; (6) closing the first valve 35, the second valve 37, the second valve 45, the seventh valve 3, the dosing pump 43 and the pressure pump 33 and opening the fourth valve 58, the fifth valve 60, the sixth valve 61 and the circulating water pump 53 when the reading of pressure gauge 4 is close to 5 bar, storing the ammonia with a mass concentration of 4%-10% and pH not lower than 10 stored in the ammonia stirring and sealed storage tank 51, transporting the ammonia through the fifth pipeline 52 to the circulating water pump 53, then through the sixth pipeline 54 to the heat exchanger 55 and heating, through the seventh pipeline 56 to the water inlet pipe 21, and then evenly distributing the ammonia to the cavities 25 of the front partition plate 12, the middle partition plates 18 and the rear partition plate 19 via the first communicating pipe 26 from the water inlet pipe 21, and in the bottom-up flow process, evenly distributing the ammonia to the surfaces of the carbon nano-material layers after being guided by the flow guide screen plates 15, which zigzags in the micro layer structure of the carbon nano-material composite membranes 16 to in-situ repair the carbon nano-material, collecting the flow by the orifice plates 17, converging it to the internal cavities 25 of the filter plates 13, and then running into the water outlet pipe 22 through the second communicating pipe 27, and transporting it to the ammonia stirring and sealed storage tank 51 by the eighth pipeline 57; wherein, controlling the flow rate of the ammonia corresponds to a membrane flux of 0.1-0.4 L.Math.min.sup.−1.Math.m.sup.−2, the thermal media used by the heat exchanger 55 is heat transfer oil, and the heat transfer oil is in countercurrent contact with the ammonia to ensure that the ammonia at the outlet of the heat exchanger 55 has a temperature of 120-150° C.; and stopping the in-situ regeneration when the reading of the pressure gauge is below 1.5 bar or after running for 4 to 8 hours.

(36) The treatment device and treatment method in the present specific implementation is particularly suitable for the raw water to be treated with a concentration of organic micro-pollutants below 0.5 mg/L, the total organic carbon concentration less than 1 mg/L, no suspended matter, and pH 6-9.

Embodiment 1

(37) The specific parameter settings of the foregoing treatment device used in this embodiment are as follows: carbon nano-material composite membrane 16: the carbon nano-material loading amount was 16 g.Math.m.sup.−2, the mass ratio of rGO and MWCNT was 3:1, the pure water flux was about 39 L.Math.(m.sup.2.Math.h.Math.bar).sup.−1, the specific resistance was preferably 1.8×10.sup.18 m.sup.−2, and the filtration area of a single membrane was 0.1 m.sup.2; rGO flakes had a diameter of 2-5 μm, a thickness of 0.8-1.2 nm, an atomic ratio of carbon to oxygen of 3.3:1, and a mono-layer rate of >95%; MWCNT had an inner diameter of 2-5 nm, an outer diameter of <8 nm, a length of 1-2 μm, and a specific surface area of >500 m.sup.2.Math.g.sup.−1; the base membrane used a nylon membrane with a diameter of 400 nm, and the filter pore diameter was preferably 0.22 μm; the plate-and-frame membrane module 1: the number of the filter plates 13 was 6, the number of the middle partition plates 18 was 5, and a total filtration area was about 1.2 m.sup.2; raw water treated in the present embodiment: the concentration of sulfamethoxazole was 0.05 mg/L, the background total organic carbon concentration was about 0.3 mg/L, no suspended matter, and the pH was about 6.8; oxidant: sodium persulfate aqueous solution; regenerant: 4% ammonia aqueous solution.

(38) The specific treatment steps comprise micro-pollutant removal and composite membrane function regeneration, specifically as follows: (1) micro-pollutant removal: the raw water flow rate was about 0.6 L.Math.min.sup.−1, the corresponding membrane flux was about 0.5 L.Math.min.sup.−1.Math.m.sup.−2; the temperature of the sodium persulfate concentrated solution was controlled at 25° C., and the oxidant flow rate was controlled about 2% of the raw water flow rate, the initial molar concentration ratio of sodium persulfate to sulfamethoxazole was 100:1; and the initial reading of pressure gauge 4 was 1.7 bar. With the extension of the treatment time, the reading of the pressure gauge 4 gradually increased, reaching 4.6 bar after 72 h of treatment. (2) composite membrane function regeneration: the circulation flow rate of ammonia was about 0.24 L.Math.min.sup.−1, and the corresponding membrane flux was 0.2 L.Math.min.sup.−1.Math.m.sup.−2; the temperature of the ammonia aqueous solution at the outlet of the heat exchanger 55 was about 122° C. The initial reading of pressure gauge 4 was 3.9 bar, then gradually decreased, and after running for 6 h, the reading of pressure gauge 4 stabilized at 1.1 bar, and the in-situ regeneration operation was stopped.

(39) Using this embodiment, the treatment-regeneration was repeated 7 times, and the operation conditions are shown in FIGS. 9 and 10. The results of Embodiment 1 show that the removal effect of sulfamethoxazole is still very good after 7 times of treatment and regeneration.

Embodiment 2

(40) The specific parameter settings of the foregoing treatment device used in this embodiment are as follows: carbon nano-material composite membrane 16: the carbon nano-material loading amount was 32 g.Math.m.sup.−2, the mass ratio of rGO and MWCNT was 2:1, the pure water flux was about 52 L.Math.(m.sup.2.Math.h.Math.bar).sub.−1, the specific resistance was preferably 1.5×10.sup.18 m.sub.−2, and the filtration area of a single membrane was 0.1 m.sup.2; rGO flakes had a diameter of 2-5 μm, a thickness of 0.8-1.2 nm, an atomic ratio of carbon to oxygen of 3.7:1, and a mono-layer rate of >95%; MWCNT had an inner diameter of 2-5 nm, an outer diameter of <8 nm, a length of 1-2 and a specific surface area of >500 m.sup.2.Math.g.sup.−1; the base membrane used a PVDF membrane with a diameter of 400 nm, and the filter pore diameter was preferably 0.45 μm; the plate-and-frame membrane module 1: the number of the filter plates 13 was 8, the number of the middle partition plates 18 was 7, and a total filtration area was about 1.6 m.sup.2; raw water treated in the present embodiment: the concentration of phenols was 0.03 mg/L, the background total organic carbon concentration was about 0.6 mg/L, no suspended matter, and the pH was about 7.4; oxidant: ozone aqueous solution; regenerant: 8% ammonia aqueous solution.

(41) The specific treatment steps comprise micro-pollutant removal and composite membrane function regeneration, specifically as follows: (1) micro-pollutant removal: the raw water flow rate was about 1.6 L.Math.min.sup.−1, the corresponding membrane flux was about 1.0 L.Math.min.sup.−1.Math.m.sup.−2; the temperature of the ozone concentrated solution was controlled at 0° C., and the oxidant flow rate was controlled about 5% of the raw water flow rate, the initial molar concentration ratio of ozone to phenols was 50:1; and the initial reading of pressure gauge 4 was 1.4 bar. With the extension of the treatment time, the reading of the pressure gauge 4 gradually increased, reaching 4.9 bar after 48 h of treatment.