Water treatment system for efficiently removing perfluorinated compounds

Abstract

The utility model relates to a water treatment system for efficiently removing perfluorinated compounds. The water treatment system comprises a front filter element, a front carbon rod, a reverse osmosis assembly and a rear carbon rod, the reverse osmosis assembly comprises a shell, a flow divider, a water collecting pipe and a filter element, wherein the flow divider comprises a water inlet, two flow dividing openings respectively communicated with the water inlet, the water collecting pipe is arranged in the shell, and the filter element is formed by winding a filter screen, a first reverse osmosis membrane, filter cloth and a second reverse osmosis membrane on the surface of the water collecting pipe and rolling the filter screen, the first reverse osmosis membrane, the filter cloth and the second reverse osmosis membrane which are sequentially stacked from outside to inside; the shell comprises a water inlet end provided with two water inlets and a water outlet end provided with a wastewater outlet and a clean water outlet; the water collecting part comprises a closed end positioned on one side of the water inlet end and an open end communicated with the clean water outlet; the end face, located at the water inlet end, of the filter element abuts against the two flow dividing openings. The outlet of the front carbon rod is communicated with the water inlet, and the clean water outlet is communicated with the inlet of the rear carbon rod. According to the utility model, perfluorinated compounds can be efficiently removed, the sewage treatment efficiency and the service life of the reverse osmosis assembly can be improved, and the production cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of water purification, in particular to a water treatment system for efficiently removing perfluorinated compounds. Background Art

[0002] Perfluorinated compounds are a class of emerging persistent organic pollutants in the environment. Among them, PFOA (perfluorooctanoic acid) and PFOS (perfluorooctane sulfonate) are two perfluoroalkyl and polyfluoroalkyl substances (PFASs) that have received particular attention. PFOA is toxic to the liver, may reduce the activity of antioxidant enzymes, affect reproduction and development, and inhibit the immune system; PFOS has liver toxicity, affects lipid metabolism, may cause a decrease in sperm count and deformities, and affect thyroid hormone levels, etc. PFOA and PFOS have stable chemical properties, are difficult to decompose in the natural environment, can accumulate in aquatic organisms, and affect humans and other organisms through the food chain. Therefore, PFOA and PFOS have attracted attention due to their persistence, bioaccumulation, and toxicity. China's "Hygienic Standard for Drinking Water" (GB5749—2022) has included them in the water quality reference indicators and specified the limit values of PFOA and PFOS to ensure the safety of drinking water and public health.

[0003] Currently, the main methods for removing or transferring PFASs include advanced oxidation processes (AOPs), electrochemistry, and membrane filtration, etc. Among them, physical adsorption is considered a promising technology for removing PFASs in water due to its simplicity, economy, high efficiency, etc. For example, granular activated carbon (GAC) and powdered activated carbon (PAC) have a high adsorption capacity for PFOS and PFOA; membrane filtration technology, especially reverse osmosis (RO), has a significant effect on the removal of PFASs in water. However, on the one hand, the existing water purification systems using membrane filtration technology have the problem of low removal rate of perfluorinated compounds; on the other hand, under the reverse osmosis concentration effect, pollutants such as sludge, colloids, and macromolecular substances in the sewage deposit and adhere to the surface of the RO membrane, resulting in membrane element fouling, causing a decline in the performance of the system, and affecting the normal use of the water purification system. Summary of the Utility Model

[0004] Based on this, to solve the above problems, the purpose of the utility model is to provide a water treatment system for efficiently removing perfluorinated compounds. By combining activated carbon adsorption technology and membrane filtration technology, the system has an efficient removal effect on perfluorinated compounds, can improve the sewage treatment efficiency and service life of the reverse osmosis module at the same time, and has a low manufacturing cost.

[0005] A water treatment system for efficiently removing perfluorinated compounds, comprising a pre-filter, a pre-carbon rod, a reverse osmosis module, and a post-carbon rod arranged in sequence; the reverse osmosis module includes a housing, a diverter, a water collecting pipe, and a filter element; the housing includes a water inlet end and a water outlet end, the water inlet end is provided with two water inlets, and the water outlet end is provided with a wastewater outlet and a clean water outlet; the water collecting pipe is arranged inside the housing and is located between the two water inlets, the water collecting pipe includes a closed end and an open end, the closed end is located on one side of the water inlet end, and the open end is communicated with the clean water outlet, and the water collecting pipe is provided with a plurality of water collecting through holes; the diverter includes a water inlet, a first diverter port and a second diverter port respectively communicated with the water inlets; the filter element is wound on the surface of the water collecting pipe by a filter screen, a first reverse osmosis membrane, a filter cloth and a second reverse osmosis membrane stacked in sequence from outside to inside, and the filter element covers all the water collecting through holes of the water collecting pipe; the end face of the filter element at the water inlet end abuts against the first diverter port and the second diverter port; the outlet of the pre-carbon rod is communicated with the water inlet, and the clean water outlet is communicated with the inlet of the post-carbon rod.

[0006] Compared with the existing water treatment system for removing perfluorinated compounds, the utility model combines the activated carbon adsorption technology and the membrane filtration technology, so that it has an efficient removal effect on perfluorinated compounds; and the reverse osmosis filtration equipment is improved, and by designing the filter element, a filter screen and a filter cloth are arranged between the RO membranes, a water flow channel is formed in the space where the filter screen and the filter cloth are located, and two streams of sewage are used to generate turbulence by convective impact in the water flow channel, so as to impact the pollutants deposited on the surface of the RO membrane and carry them away for discharge, realizing the cleaning of the RO membrane; thereby realizing the removal of pollutants on the surface of the RO membrane while treating sewage, avoiding the performance degradation of the reverse osmosis module, improving its service life, and reducing the production cost.

[0007] Further, the first diverter port is provided with a first flow valve for controlling the water flow rate, and the second diverter port is provided with a second flow valve for controlling the water flow rate. By setting the diverter to control the sewage flow rate at the water inlet, the confluence and collision of sewage at different positions in the water flow channel are controlled to generate turbulence, so as to realize the removal of pollutants at different positions on the surface of the RO membrane.

[0008] Further, a partition board is further included, and the end face of the filter element and the housing enclose a water inlet cavity at the water inlet end. The partition board is hermetically connected between the closed end of the water collecting pipe and the inner wall of the housing, isolating the water inlet cavity into a first space and a second space, and the first diverter port and the second diverter port are respectively located in the first space and the second space. Avoid the mixing of the two streams of sewage before flowing into the filter element, resulting in a reduction in the impact force caused by the mixing of the two streams of sewage in the filter element, thereby weakening the cleaning effect on the surface of the RO membrane.

[0009] Furthermore, the front carbon rod and the rear carbon rod are made of activated carbon, the particle size of the activated carbon powder is less than 5 nm, and the BET specific surface area of the activated carbon powder > 1000 / m 2 ·g -1 . Through research by the applicant, it is found that by selecting the above-mentioned activated carbon powder, the activated carbon powder has the best adsorption effect on PFOS adsorbate molecules and PFOA adsorbate molecules, which can greatly improve the removal rate of perfluorinated compounds in the entire water treatment system.

[0010] Furthermore, the pores of the activated carbon powder of the front carbon rod and the rear carbon rod are less than 5 μm. The smaller the particle size of the carbon powder, the higher the forming precision of the carbon rod (i.e., the smaller the pores of the carbon rod). However, the higher the precision of the carbon rod, the stronger its interception ability. Therefore, it is necessary to increase the reverse osmosis membrane area of the reverse osmosis module to increase the water flow velocity of the system. Otherwise, the water flow velocity of the subsequent booster pump will be too small, resulting in greater noise. Through research by the applicant, it is found that on the basis of limiting the particle size and specific surface area of the above-mentioned activated carbon powder, the pores between the particles of the activated carbon powder are less than 5 μm. At this time, the carbon rod not only has a better adsorption effect on perfluorinated compounds, but also can make the pressure loss rate of the carbon rod (i.e., the proportion of the reduced fluid pressure) less than 10%, having the advantage of small interception ability and avoiding greater noise in the water removal system.

[0011] Furthermore, the activated carbon powder is coconut shell activated carbon powder.

[0012] Furthermore, the activated carbon powder for preparing the front carbon rod and the rear carbon rod includes carbon powder with a particle size of 2 nm and a volume percentage of 90 - 100%.

[0013] Furthermore, the first reverse osmosis membrane and the second reverse osmosis membrane include a desalination layer and a non-woven fabric base layer; the desalination rate of the desalination layer is at least 97%.

[0014] Furthermore, the first reverse osmosis membrane and / or the second reverse osmosis membrane further include a support layer between the desalination layer and the non-woven fabric base layer, and the support layer is a polysulfone support layer.

[0015] Furthermore, the pre-filter is a polyethylene filter element or a polypropylene filter element.

[0016] For better understanding and implementation, the present utility model will be described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic structural diagram of a water treatment system for efficiently removing perfluorinated compounds according to the present utility model;

[0018] Figure 2Schematic structural diagram of the reverse osmosis module described in this utility model;

[0019] Figure 3 Internal structural schematic diagram of the filter element and the water collecting pipe described in this utility model;

[0020] Figure 4 Cross-sectional schematic diagram of the filter element and the water collecting pipe described in this utility model. Detailed implementation manners

[0021] It should be clear that the described embodiments are only a part of the embodiments of this application, rather than all of them. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope protected by the embodiments of this application.

[0022] The terms used in the embodiments of this application are only for the purpose of describing specific embodiments, and are not intended to limit the embodiments of this application. The singular forms "a", "the" and "said" used in the embodiments of this application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0023] When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementation manners described in the following exemplary embodiments do not represent all implementation manners consistent with this application. On the contrary, they are only examples of the devices and methods consistent with some aspects of this application as detailed in the appended claims.

[0024] In the description of this application, it should be understood that the terms "first", "second", "third", etc. are only used to distinguish similar objects, and do not have to be used to describe a specific order or sequence, nor can they be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0025] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "left", "right", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to this utility model.

[0026] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0027] In addition, in the description of the present application, unless otherwise stated, "a plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally represents an "or" relationship between the associated objects before and after.

[0028] It should be understood that the embodiments of the present application are not limited to the precise structures already described and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the embodiments of the present application is only limited by the appended claims.

[0029] Please refer to Figure 1 , a water treatment system for efficiently removing perfluorinated compounds of the present utility model includes a pre-filter 1, a pre-activated carbon rod 2, a reverse osmosis module 3, and a post-activated carbon rod 4 arranged in sequence.

[0030] In this embodiment, the pre-filter 1 is a polyethylene filter or a polypropylene filter; the function of the pre-filter 1 is to intercept macromolecular solid substances and colloids in the sewage to avoid clogging the subsequent pre-activated carbon rod 2, reverse osmosis module 3, and post-activated carbon rod 4.

[0031] The pre-activated carbon rod 2 and the post-activated carbon rod 4 are mainly used to absorb PFOS adsorbate molecules and PFOA adsorbate molecules in the sewage. The diameter of PFOS adsorbate molecules is about 1.056 nm, and the diameter of PFOA adsorbate molecules is about 0.991 nm. The applicant found that the activated carbon powder with a particle size less than 5 nm has the best adsorption effect on PFOS adsorbate molecules and PFOA adsorbate molecules. Therefore, the pre-activated carbon rod 2 and the post-activated carbon rod 4 of the present utility model are made of activated carbon powder with a particle size less than 5 nm, and the BET specific surface area of the activated carbon powder > 1000 / m 2 ·g -1Preferably, the average particle size of the activated carbon powder is 2-3 nm, and the activated carbon powder is coconut shell activated carbon powder. In this embodiment, the activated carbon powder for preparing the front carbon rod 2 and the rear carbon rod 4 is composed of carbon powder with a particle size of 2 nm and a volume percentage of 90-100% and other carbon powder with a particle size less than 5 nm and a volume percentage of 0-10%.

[0032] Furthermore, the smaller the particle size of the carbon powder, the higher the forming precision of the carbon rod (i.e., the smaller the pores of the carbon rod). However, the higher the precision of the carbon rod, the stronger its interception ability. Therefore, it is necessary to increase the reverse osmosis membrane area of the reverse osmosis module to increase the water flow velocity of the system. Otherwise, the water flow velocity of the subsequent booster pump will be too small, resulting in a large noise. In this regard, the applicant found that when the pores between the carbon powder of the carbon rod are less than 5 μm, it can not only ensure the precision of the carbon rod to have a good adsorption effect, but also make the pressure loss rate of the carbon rod (i.e., the proportion of the reduced fluid pressure) less than 10%, having the advantage of small interception ability. Therefore, further, the pores between the activated carbon powder of the front carbon rod 2 and the rear carbon rod 4 are less than 5 μm.

[0033] Please refer to the atta Figure 2 , the reverse osmosis module 3 includes a housing 32, a diverter 33, a water collecting pipe 34, a filter element 35 and a partition plate 36.

[0034] Both ends of the housing 32 are respectively a water inlet end and a water outlet end. There are two water inlets provided on the left and right sides of the water inlet end, and there are two mutually connected wastewater outlets and a clean water outlet provided at the water outlet end.

[0035] The diverter 33 of this embodiment is arranged outside the housing 32. In this embodiment, the diverter 33 is a "Y"-shaped diverter; the diverter 33 includes a water inlet 331, a first diversion port 333 and a second diversion port 334 that are respectively connected to the two water inlets of the housing 32, and the water inlet 331, the first diversion port 333 and the second diversion port 334 are interconnected. A first flow valve 336 for controlling the water flow rate is provided at the first diversion port 333, and a second flow valve 337 for controlling the water flow rate is provided at the second diversion port 334. The outlet of the front carbon rod 2 is connected to the water inlet 331, and the clean water outlet is connected to the inlet of the rear carbon rod 4.

[0036] The water collecting pipe 34 is arranged inside the housing 32 and is located between the two water inlets; the water collecting pipe 34 includes a closed end and an open end, the closed end is located on the side of the water inlet end, and the open end is connected to the clean water outlet at the water outlet end of the housing 32; several water collecting through holes 342 communicating with the inner space of the pipe are provided on the surface of the water collecting pipe 34.

[0037] Please refer to the attaFigures 3 - 4 The filter element 35 includes a filter screen 351, a first reverse osmosis membrane 352, a filter cloth 353, and a second reverse osmosis membrane 354 that are stacked in sequence from outside to inside; the filter element 35 is wound around the surface of the water collecting pipe 34 to form a cylindrical structure, and the filter element 35 covers all the water collecting through holes 342 on the surface of the water collecting pipe 34; the end face of the filter element 35 at the water inlet end abuts against the first diversion port 333 and the second diversion port 334 of the diverter 33; the end face of the filter element 35 and the housing 2 enclose a water inlet chamber at the water inlet end; the space where the filter screen 351 and the filter cloth 353 are located forms a water flow channel between the first reverse osmosis membrane 352 and the second reverse osmosis membrane 354. Preferably, the filter screen 351 is a PP filter screen, and the filter cloth 353 is a PET filter cloth. The first reverse osmosis membrane 352 and the second reverse osmosis membrane 354 are composed of a desalination layer, a support layer, and a non-woven fabric base layer; in other embodiments, the first reverse osmosis membrane 352 and the second reverse osmosis membrane 354 can also be composed of a polyamide desalination layer and a non-woven fabric base layer. The desalination rate of the desalination layer is at least 97%. Preferably, the desalination layer is a polyamide desalination layer, the support layer is a polysulfone support layer, and the non-woven fabric base layer is a polypropylene non-woven fabric base layer. In other embodiments, the first reverse osmosis membrane 352 and the second reverse osmosis membrane 354 are protein membranes. The sewage treated by the pre-filter carbon rod 2 enters the reverse osmosis module 3 from the water inlet 331 and then flows out from the clean water outlet to the post-filter carbon rod 4.

[0038] A partition plate 36 is provided between the two water inlets of the housing 32. The partition plate 36 is hermetically connected between the closed end of the water collecting pipe 34 and the inner wall of the housing 32. The bottom of the partition plate 36 is hermetically connected to the closed end of the water collecting pipe, and the top and both ends of the partition member 36 are hermetically connected to the inner wall of the water inlet end of the housing 32; in other embodiments, the water collecting pipe 34 and the partition plate 36 can also be integrally injection-molded. The partition plate 36 divides the water inlet chamber into a first space and a second space, and the first diversion port 333 and the second diversion port 334 are respectively located in the first space and the second space. In other embodiments, the partition plate 36 can also be integrated with the housing 32. The partition plate 36 isolates the sewage entering the housing 32 from the two water inlets on the left and right sides of the housing 32, preventing the mixing of the two sewage streams.

[0039] On the one hand, the filter screen 351 and the filter cloth 353 can intercept macromolecular solid substances and colloids, avoiding blockage on the surfaces of the first reverse osmosis membrane 352 and the second reverse osmosis membrane 354. On the other hand, they can enable the sewage to flow along the filter screen 351 and the filter cloth 353, being evenly distributed on the surfaces of the first reverse osmosis membrane 352 and the second reverse osmosis membrane 354, avoiding the problem that the sewage is squeezed at a certain position on the surfaces of the first reverse osmosis membrane 352 and the second reverse osmosis membrane 354, resulting in the adhesion of pollutants on the membrane sheets, slow sewage flow rate, poor filtration effect, and even damage to the membrane sheets. The larger the mesh number and / or thickness of the filter screen 351 and the filter cloth 353, on the one hand, the better the pollutant removal effect, and on the other hand, the wider the water flow channel formed between the filter screen 351 and the filter cloth 353 between the first reverse osmosis membrane 352 and the second reverse osmosis membrane 354, which can not only accelerate the flow rate of the sewage towards the water outlet end, but also better guide the sewage towards the collecting pipe 34, accelerating the efficiency of sewage treatment.

[0040] The sewage enters the housing 32 from the first diversion port 333 and the second diversion port 334 and converges and collides in the water flow channel of the filter element 35 to generate turbulence. The turbulence will impact the pollutants deposited on the surfaces of the first reverse osmosis membrane 352 and the second reverse osmosis membrane 354 and carry them away to be discharged towards the waste water outlet, realizing the cleaning of the first reverse osmosis membrane 352 and the second reverse osmosis membrane 354, avoiding the residue of perfluorinated compounds on the RO membrane surface, reducing the membrane pollution and the occurrence of poor performance and increased concentration polarization phenomenon, and restoring its performance. The diverter 33 can adjust the water inflow amounts of the first diversion port 333 and the second diversion port 334 respectively through the first flow valve 336 and the second flow valve 337, enabling the two water streams to converge and collide at different positions in the water flow channel on the surfaces of the first reverse osmosis membrane 352 and the second reverse osmosis membrane 354 to generate turbulence, thereby realizing the removal of pollutants at different positions on the surfaces of the first reverse osmosis membrane 352 and the second reverse osmosis membrane 354, which is beneficial to improving the service life of the reverse osmosis module.

[0041] In this application, the same batch of sewage (the perfluorinated compound content in the sewage is 400 PPT) is treated by an existing water treatment system and the water treatment system of the present utility model for highly efficient removal of perfluorinated compounds respectively. The perfluorinated compound content at the inlet and outlet of each treatment unit is detected respectively, and the perfluorinated compound removal rate after the sewage flows through each treatment unit is calculated. The test results are shown in Table 1 below.

[0042] An efficient water treatment system for removing perfluorinated compounds of the present utility model first allows the sewage containing perfluorinated compounds to enter the pre-filter element 1 to filter out macromolecular solid substances and colloids in the sewage, and then passes through the pre-carbon rod 2 made of coconut shell activated carbon powder with a particle size less than 5 nm and a BET specific surface area > 1000 / m 2 ·g -1 to filter out most of the perfluorinated compounds in the sewage. Then, it passes through the reverse osmosis module 3. The sewage flows through the filter element 35 to the collecting pipe 34 and flows out to the post-carbon rod 4. Part of the perfluorinated compounds absorbed by the filter element 35 are flushed out and recycled. The post-carbon rod 4 made of coconut shell activated carbon powder with a particle size less than 5 nm and a BET specific surface area > 1000 / m 2 ·g -1 and with pores less than 5 μm finally conducts enhanced purification, and finally, the purified water with a perfluorinated compound removal rate as high as 99% flows out.

[0043] Table 1 Results of water treatment comparative tests

[0044]

[0045] The above embodiments only represent several implementation manners of the present utility model, and the description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the utility model patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present utility model, several modifications and improvements can still be made, and the present utility model also intends to include these changes and modifications.

Claims

1. An efficient water treatment system for removing perfluorinated compounds, characterized in that: It includes a pre-filter, a pre-carbon rod, a reverse osmosis module, and a post-carbon rod arranged in sequence; the reverse osmosis module includes a housing, a diverter, a water collecting pipe, and a filter element; the housing includes a water inlet end and a water outlet end, the water inlet end is provided with two water inlets, and the water outlet end is provided with a waste water outlet and a clean water outlet; the water collecting pipe is arranged inside the housing and is located between the two water inlets, the water collecting pipe includes a closed end and an open end, the closed end is located on one side of the water inlet end, the open end is communicated with the clean water outlet, and the water collecting pipe is provided with a plurality of water collecting through holes; the diverter includes a water inlet, a first diversion port and a second diversion port respectively communicated with the water inlets; the filter element is wound on the surface of the water collecting pipe and formed by laminating a filter screen, a first reverse osmosis membrane, a filter cloth and a second reverse osmosis membrane from outside to inside in sequence, and the filter element covers all the water collecting through holes of the water collecting pipe; the end face of the filter element at the water inlet end abuts against the first diversion port and the second diversion port; the outlet of the pre-carbon rod is communicated with the water inlet, and the clean water outlet is communicated with the inlet of the post-carbon rod.

2. The water treatment system for efficiently removing perfluorinated compounds according to claim 1, characterized in that: The first diversion port is provided with a first flow valve for controlling the water flow rate, and the second diversion port is provided with a second flow valve for controlling the water flow rate.

3. The water treatment system for efficiently removing perfluorinated compounds according to claim 1, wherein: It further includes a partition board. The end face of the filter element and the housing enclose a water inlet cavity at the water inlet end. The partition board is hermetically connected between the closed end of the water collecting pipe and the inner wall of the housing, and divides the water inlet cavity into a first space and a second space. The first diversion port and the second diversion port are respectively located in the first space and the second space.

4. The water treatment system for efficiently removing perfluorinated compounds according to any one of claims 1-3, characterized in that: The preposed carbon rod and the postposed carbon rod are made of activated carbon, the particle size of the activated carbon powder is less than 5 nm, and the BET specific surface area of the activated carbon powder > 1000 / m 2 ·g -1 .

5. The water treatment system for efficiently removing perfluorinated compounds according to claim 4, wherein: The pore size of the activated carbon powder of the pre-carbon rod and the post-carbon rod is less than 5 μm.

6. The water treatment system for efficiently removing perfluorinated compounds according to claim 5, wherein: The activated carbon powder is coconut shell activated carbon powder.

7. The water treatment system for efficiently removing perfluorinated compounds according to claim 6, characterized in that: The activated carbon powder for preparing the pre-carbon rod and the post-carbon rod includes carbon powder with a particle size of 2 nm and a volume percentage of 90-100%.

8. The water treatment system for efficiently removing perfluorinated compounds according to any one of claims 5-7, characterized in that: The first reverse osmosis membrane and the second reverse osmosis membrane include a desalination layer and a non-woven fabric base layer; the desalination rate of the desalination layer is at least 97%.

9. The water treatment system for efficiently removing perfluorinated compounds according to claim 8, wherein: The first reverse osmosis membrane and / or the second reverse osmosis membrane further includes a support layer between the desalination layer and the non-woven fabric base layer, and the support layer is a polysulfone support layer.

10. The water treatment system for efficiently removing perfluorinated compounds according to claim 9, characterized in that: The pre-filter is a polyethylene filter or a polypropylene filter.

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