Indoor water purification equipment

Abstract

The utility model relates to indoor water purification equipment which comprises a machine shell, a pre-filtering system, a filtering system, a control system and a water production system are arranged in the machine shell, and a water supply system is arranged outside the machine shell. Wherein the pre-filtration system is used for filtering particles with the particle size of 20-150 microns in tap water, the filtration system is used for producing drinking water containing mineral substances, the water production system is used for storing the drinking water produced by the filtration system, the water supply system comprises a water supply pipeline, and the inlet end of the water supply pipeline is communicated with the outlet end of the water production system; a variable-frequency water pump and a stop valve are sequentially arranged on the water supply pipeline, a water taking opening is formed in the tail end of the water supply pipeline, and the control system is used for circulation and closing of all the pipelines. The utility model mainly aims to provide indoor water purification equipment, which can shorten the filtering process and can keep the balance of mineral substances in drinking water at the same time.

Description

Technical Field

[0001] This utility model relates to a water treatment device, specifically an indoor water purification device. Background Technology

[0002] Household water purifiers can effectively remove bacteria, heavy metals, chemical pollutants, and impurities from tap water, ensuring drinking water safety and reducing long-term health risks. They also improve the taste of water, eliminate residual chlorine, off-colors, and odors, reduce reliance on bottled water to save costs, and reduce plastic pollution. They are a key choice for improving quality of life and health protection, especially for families with infants, the elderly, or those in areas with poor water quality.

[0003] Existing water purification equipment involves a complex process: sand filtration → activated carbon filtration → microfiltration → ultrafiltration → chemical dosing → pH adjustment → high-pressure pump → reverse osmosis membrane → pH adjustment → disinfection → ion exchange → effluent. This results in large-scale water purification systems that require significant floor space when used in homes or large indoor spaces. Furthermore, these filtration methods remove beneficial minerals from the water, necessitating the supplementation of these mineral-deficient waters through other means. Therefore, ultrafiltration membranes are used for subsequent water purification. Ultrafiltration membranes utilize a sieving principle, separating large molecules, colloids, bacteria, and viruses through micropores in the membrane. These pores, typically between 0.01 and 0.1 micrometers, effectively remove large particulate contaminants while allowing minerals and smaller ions to pass through. Therefore, ultrafiltration membranes are often used to retain beneficial minerals in water. However, they cannot filter small molecules (such as heavy metal ions and dissolved salts). Thus, ultrafiltration focuses on basic purification, and the mineral balance in drinking water filtered through ultrafiltration membranes may still be compromised. Utility Model Content

[0004] The main purpose of this invention is to provide an indoor water purification device that can shorten the filtration process while maintaining the mineral balance in drinking water.

[0005] To achieve the above objectives, this utility model provides a feature comprising a housing, with an inlet and an outlet on the side of the housing; and an interior of the housing containing:

[0006] The pre-filtration system is used to filter particles with a diameter of 20μm-150μm in tap water. The pre-filtration system includes an inlet pipeline, on which an electric inlet control valve, a filter and an inlet flow meter are installed in sequence.

[0007] The filtration system is used to produce drinking water containing minerals. The end of the inlet pipeline is connected to the inlet end located at the bottom of the filtration system. The top of the filtration system is equipped with a concentrate pipeline, which is connected to the first outlet of the filtration system. The concentrate pipeline discharges the filtered water produced by the filtration system to the outside of the water purification equipment. The concentrate pipeline is equipped with a concentrate electric control valve.

[0008] The water production system is used to store the drinking water produced by the filtration system. The water production system includes a water production pipeline. The inlet end of the water production pipeline is connected to the second outlet of the filtration system, and the outlet end of the water production pipeline is connected to the water production system. A water production flow meter, a water production electric control valve, and a carbon filter element are installed sequentially on the water production pipeline.

[0009] The machine casing is equipped with a water supply system, which includes a water supply pipeline. The inlet end of the water supply pipeline is connected to the outlet end of the water production system. A variable frequency water pump and a shut-off valve are installed in sequence on the water supply pipeline, and a water intake is provided at the end of the water supply pipeline.

[0010] The control system is electrically connected to the inlet electric control valve, the product water electric control valve, the concentrate electric control valve, and the variable frequency water pump.

[0011] Preferably, the filtration system is a hollow fiber nanofiltration membrane; the water production system is located in the water production tank.

[0012] In a further preferred embodiment, the product water tank is located on the back side inside the casing, while the hollow fiber nanofiltration membrane and the control system are both located in front of the product water tank and arranged side by side.

[0013] Furthermore, the casing is equipped with a backwash line. The inlet of the backwash line is connected to the outlet of the product water tank, and the outlet of the backwash line is connected to the second outlet of the hollow fiber nanofiltration membrane. The backwash line is equipped with a backwash electric control valve, which is electrically connected to the control system. The backwash line is used to balance the water concentration inside the hollow fiber nanofiltration membrane when the water purification equipment is not in operation.

[0014] Furthermore, the casing is equipped with a positive flushing pipeline. The inlet end of the positive flushing pipeline is connected to the outlet end of the product water tank, and the outlet end of the positive flushing pipeline is connected to the inlet end of the hollow fiber nanofiltration membrane. A positive flushing electric control valve is installed on the positive flushing pipeline, which is electrically connected to the control system. The positive flushing pipeline is used to balance the water concentration inside the hollow fiber nanofiltration membrane when the water purification equipment is not in operation.

[0015] In a further preferred embodiment, the casing is also equipped with a venting line. The inlet end of the venting line is connected to the inlet end of the hollow fiber nanofiltration membrane, and the outlet end of the venting line is connected to the concentrate line. The venting line is used to vent the water stored in the hollow fiber nanofiltration membrane, and a venting valve is provided on the venting line.

[0016] In a further preferred embodiment, the machine casing is also equipped with a water production discharge pipeline. The inlet end of the water production discharge pipeline is connected to the second outlet of the hollow fiber nanofiltration membrane. The water production discharge pipeline is equipped with an electric discharge control valve, which is electrically connected to the control system.

[0017] In a further preferred embodiment, the machine casing is also equipped with a return water pipeline. The inlet end of the return water pipeline is connected to the outlet end of the product water tank, and the outlet end of the return water pipeline is connected to the inlet water pipeline. The return water pipeline is used to discharge the water stored in the supply water pipeline into the product water tank, where it is disinfected a second time by an ultraviolet disinfection device inside the product water tank.

[0018] In a further preferred embodiment, the outer casing is also equipped with two pipelines, the inlet end of which is connected to the water inlet pipeline, and the outlet end of which is connected to the water supply pipeline.

[0019] Further preferably, the membrane shell of the hollow fiber nanofiltration membrane is cylindrical.

[0020] The beneficial effects of this utility model are as follows:

[0021] This invention features a streamlined water purification process: ordinary filter → nanofiltration membrane → carbon filtration → disinfection → water output, significantly reducing the overall flow. The pre-filtration system filters particles in tap water with a diameter of 20μm-150μm, reducing the burden on subsequent filtration systems and extending their lifespan. The filtration system uses a hollow fiber nanofiltration membrane, producing drinking water containing minerals. While removing harmful substances, it retains beneficial minerals, improving drinking water quality. Utilizing backwash and forward flushing lines, when the water purification equipment is not in operation, the backwash line balances the water concentration inside the hollow fiber nanofiltration membrane. Controlled by an electric backwash valve, water is drawn from the product water tank to backwash the hollow fiber nanofiltration membrane, helping to prevent membrane fouling, extend membrane lifespan, and ensure filtration effectiveness.

[0022] Meanwhile, the hollow fiber nanofiltration membrane in this invention has a conical membrane shell, and the second outlet enters the membrane shell tangentially. This design helps to form a special water flow state during the filtration process, promotes the improvement of filtration effect, and makes the water flow form a rotating flow inside the membrane shell, which enhances the scouring effect on the membrane surface, reduces the deposition of impurities on the membrane surface, and further improves the filtration efficiency and service life of the membrane. Attached Figure Description

[0023] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0024] Figure 1 This is a three-dimensional structural diagram of the indoor water purification device of this utility model;

[0025] Figure 2 This is a schematic diagram of the internal structure of the indoor water purification device of this utility model;

[0026] Figure 3 This is a schematic diagram of the internal structure of the indoor water purification device of this utility model from another angle;

[0027] Figure 4 A schematic diagram of the pipeline connection for the indoor water purification equipment of this utility model.

[0028] Explanation of reference numerals in the attached figures

[0029] 1. Hollow fiber nanofiltration membrane; 2. Control system; 3. Product water tank; 4. Housing;

[0030] 10. Water inlet; 20. Water outlet; 30. Front flush inlet; 40. Drinking water outlet;

[0031] 50. Circulating return water inlet;

[0032] 100. Water inlet pipeline; 110. Electric water inlet control valve; 120. Filter;

[0033] 130. Inlet flow meter;

[0034] 200. Product water pipeline; 210. Product water flow meter; 220. Product water electric control valve;

[0035] 230. Carbon filter element;

[0036] 300. Water supply pipeline; 310. Variable frequency water pump; 320. Shut-off valve;

[0037] 330. Water point;

[0038] 400. Backwash line; 410. Backwash electric control valve;

[0039] 500. Concentrate pipeline; 510. Concentrate electric control valve;

[0040] 600. Positive-jet pipeline; 610. Positive-jet electric control valve;

[0041] 700. Wastewater discharge pipeline; 710. Electric discharge control valve;

[0042] 800. Return water pipeline; 810. Return water electric control valve;

[0043] 900, Second Pipeline. Detailed Implementation

[0044] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Many specific details are set forth in the following description to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0045] like Figures 1 to 4 As shown, this embodiment provides an indoor water purification device, including a housing 4, on which an openable door is provided, through which the internal equipment can be maintained.

[0046] The internal equipment of the casing 4 includes a pre-filtration system, a filtration system, a water production system, and a control system 2. The pre-filtration system filters particles with a diameter of 20μm-150μm from tap water. The larger the particle size in the pre-filtration system, the lower the filtration precision, and vice versa. Choosing a filtration precision that is too high or too low will affect the system; too high a precision will cause clogging of the pre-filtration system, and too low a precision will cause clogging of the filtration system. This embodiment uses particles of 30μm-75μm, which can effectively intercept 30-75μm particles in tap water (such as sediment and rust), extending the service life of the filtration system and effectively reducing the risk of clogging.

[0047] In this embodiment, the pre-filtration system includes an inlet pipeline 100, on which an inlet electric control valve 110, a filter 120, and an inlet flow meter 130 are sequentially installed. It should be noted that the installation positions of the various instruments in this embodiment are based on the direction of water flow in each pipeline. The inlet electric control valve 110 and the inlet flow meter 130 are electrically connected to the control system 2. An inlet 10 is provided on the side of the casing 4. External tap water enters the inlet pipeline 100 through the inlet 10, and after preliminary filtration by the filter 120, the tap water enters the filtration system.

[0048] The filtration system further filters the pre-filtered tap water to produce drinking water containing minerals. The end of the inlet pipe 100 is connected to the inlet located at the bottom of the filtration system. A concentrate pipe 500 is located at the top of the filtration system and is connected to the first outlet of the filtration system. The concentrate pipe 500 discharges the filtered water produced by the filtration system through the outlet 20 to the outside of the water purification equipment. A concentrate electric control valve 510, electrically connected to the control system 2, is installed on the concentrate pipe 500. In this embodiment, the filtration system is a hollow fiber nanofiltration membrane 1, which selectively filters divalent and higher ions (such as heavy metals, calcium and magnesium ions) and organic matter in the water, while retaining some monovalent minerals (such as potassium and sodium), thereby producing drinking water containing minerals.

[0049] The water produced by the filtration system is stored through a water production system. Specifically, the water production system includes a water production pipeline 200, whose inlet is connected to the second outlet of the filtration system, and whose outlet is connected to the water production system. A water production flow meter 210, a water production electric control valve 220, and a carbon filter element 230 are sequentially installed on the water production pipeline 200. Thus, the carbon filter element 230 serves as a supplementary purification step after hollow fiber nanofiltration, addressing residual chlorine, odor, and small molecule organic matter. This embodiment utilizes a combination of hollow fiber nanofiltration membrane 1 and carbon filter element 230 to achieve dual purification through "physical sieving (nanofiltration) + chemical adsorption (activated carbon)," covering a wider range of pollutants while balancing mineral retention and deep purification needs. This combination overcomes the limitations of nanofiltration technology, ultimately ensuring safe water quality, excellent taste, and meeting the high standards for direct drinking water in homes.

[0050] In this embodiment, the water production system is a water production tank 3. An ultraviolet sterilization device is also provided on one side of the water production tank 3 to kill microorganisms in the water production tank 3 and ensure the safety of the stored water.

[0051] In this embodiment, the water supply system is located outside the casing 4. The water supply system includes a water supply pipeline 300, the inlet of which is connected to the outlet of the water production system. The water supply pipeline 300 exits through a drinking water outlet 40 located at the bottom of the casing 4. A variable frequency water pump 310 and a shut-off valve 320, both electrically connected to the control system 2, are sequentially installed on the water supply pipeline 300. A water intake is located at the end of the water supply pipeline 300. Simultaneously, the outlet of the water supply pipeline 300 flows into the water production tank 3 inside the casing 4 through a circulating return water inlet 50 located at the top of the casing 4. Furthermore, a water supply electric control valve 340, electrically connected to the control system 2, is also installed on the water supply pipeline 300. The water supply electric control valve 340 is located between the water intake point 330 and the circulating return water inlet 50.

[0052] In this embodiment, as Figure 2 and Figure 3 As shown, the product water tank 3 is located on the back side inside the casing 4, and the hollow fiber nanofiltration membrane 1 and the control system 2 are both located in front of the product water tank 3, and the two are arranged side by side.

[0053] In addition, in this embodiment, a backwash line 400 is also provided inside the housing 4. The inlet end of the backwash line 400 is connected to the outlet end of the product water tank 3, and the outlet end of the backwash line 400 is connected to the second outlet of the hollow fiber nanofiltration membrane 1. A backwash electric control valve 410 electrically connected to the control system 2 is provided on the backwash line 400. The backwash electric control valve 410 is electrically connected to the control system 2. The backwash line 400 is used to balance the water concentration inside the hollow fiber nanofiltration membrane 1 when the water purification equipment is not in operation. At the same time, the backwash line 400 is also used to rinse impurities on the surface of the membrane core of the hollow fiber nanofiltration membrane 1. In this embodiment, the membrane shell of the hollow fiber nanofiltration membrane 1 is cylindrical.

[0054] In other embodiments, the membrane shell of the hollow fiber nanofiltration membrane 1 can also be designed as a cone shape, with the water entering the membrane shell tangentially at the second outlet of the hollow fiber nanofiltration membrane 1. This helps to create a special water flow state during the membrane core cleaning process, causing the water to form a rotating flow within the membrane shell, enhancing the scouring effect on the membrane surface, reducing the deposition of impurities on the membrane surface, and thus further improving the membrane's filtration efficiency and service life. The backwash line 400 needs to provide a certain working pressure during the backwashing process to complete the backwashing operation. Increasing the backwash pressure is to balance the pressure difference inside and outside the membrane. This is because during normal operation of the water purification equipment, there is a certain pressure difference between the inside and outside of the hollow fiber nanofiltration membrane 1, allowing water to pass through the membrane core for filtration. When backwashing is performed, this pressure difference needs to be broken, allowing water to flow in the opposite direction into the membrane core. The additional working pressure helps to balance the pressure inside and outside the membrane core, promoting the reverse flow of water, thereby achieving cleaning of the inside of the membrane core and ensuring that contaminants inside the membrane core are effectively flushed away, guaranteeing the overall performance of the membrane core.

[0055] In this embodiment, a forward flushing pipeline 600 is also provided inside the housing 4. The inlet end of the forward flushing pipeline 600 is connected to the outlet end of the product water tank 3. The forward flushing pipeline 600 enters the housing 4 through the forward flushing port 30 provided on the housing 4. The outlet end of the forward flushing pipeline 600 is connected to the inlet end of the hollow fiber nanofiltration membrane 1. A forward flushing electric control valve 610 is provided on the forward flushing pipeline 600, which is electrically connected to the control system 2. The forward flushing pipeline 600 is mainly used to balance the water concentration inside the hollow fiber nanofiltration membrane 1 when the water purification equipment is not in operation. Both the forward flushing pipeline 600 and the backwashing pipeline 400 draw water directly from the product water tank 3 to flush the hollow fiber nanofiltration membrane 1. The forward flushing pipeline 600 does not need to provide additional working pressure during operation, indicating that their working requirements are different. The forward flushing pipeline 600 is only capable of cleaning impurities on the surface of the membrane core.

[0056] In this embodiment, a venting line is also provided inside the housing 4. The inlet end of the venting line is connected to the inlet end of the hollow fiber nanofiltration membrane 1, and the outlet end of the venting line is connected to the end of the concentrate line 500. The venting line is used to vent the water stored in the hollow fiber nanofiltration membrane 1, and an electric venting control valve is provided on the venting line. This avoids problems such as bacterial growth or water deterioration caused by prolonged standing, and is beneficial to the maintenance and upkeep of the equipment.

[0057] In this embodiment, the casing 4 is further equipped with a water discharge pipeline 700. The inlet end of the water discharge pipeline 700 is connected to the second outlet of the hollow fiber nanofiltration membrane 1. The water discharge pipeline 700 is equipped with a discharge electric control valve 710, which is electrically connected to the control system 2. The purpose of the water discharge pipeline 700 is to discharge the flushing water to the floor drain, ensuring that the water inside the water tank is clean and hygienic, as the newly installed hollow fiber nanofiltration membrane 1 needs to be flushed.

[0058] In this embodiment, a return water pipeline 800 is also provided inside the casing 4. The inlet end of the return water pipeline 800 is connected to the end of the water intake point 330, and the outlet end of the return water pipeline 800 is connected to the product water tank 3. The return water pipeline 800 is used to discharge the water stored in the water supply pipeline 300 into the product water tank 3. The purpose of the return water pipeline 800 is to prevent excessive microorganisms from growing in the water stored between the product water tank 3 and the water intake point 330 due to prolonged disuse. Therefore, the water stored in the water supply pipeline 300 needs to be disinfected twice, thereby improving water utilization, avoiding water waste, and also helping to ensure the quality of the produced water.

[0059] In addition, in this embodiment, in addition to the water purification equipment, two pipelines 900 are also installed between the water intake point 330 and the tap water. The purpose of the two pipelines 900 is to ensure that the water intake point 330 can continue to supply water when the water purification equipment is damaged or under repair.

[0060] The specific water purification process in this embodiment is as follows:

[0061] S100: The water purification equipment is powered on and running.

[0062] Control system 2 confirms whether it is the first time to start up. If it is the first time to start up, it cleans the hollow fiber nanofiltration membrane 1. If not, it starts to execute step S200.

[0063] In this step, if it is the first time to start up, the control system 2 opens the inlet electric control valve 110, the concentrate electric control valve 510 and the drain electric control valve 710, closes the electric control valves on other pipelines, cleans the hollow fiber nanofiltration membrane 1, and after the preset cleaning time, closes the drain electric control valve 710 and opens the product water electric control valve 220.

[0064] S200: Control system 2 detects whether the electric control valves on each pipeline are in working condition: keep the inlet electric control valve 110, concentrate electric control valve 510, product water electric control valve 220 and supply electric ball valve 340 in the open state, and keep the electric control valves on other pipelines in the closed state.

[0065] S300: Tap water is introduced into the inlet pipeline 100. After initial filtration by the filter 120, the tap water undergoes secondary filtration through the hollow fiber nanofiltration membrane 1, and then undergoes tertiary filtration through the carbon filter element 230 on the product water pipeline 200 before entering the product water tank 3 for storage. The generated concentrate is discharged through the concentrate pipeline 500.

[0066] In this step, a water quality analyzer and a conductivity analyzer are installed on the water supply pipeline 300 and the water production pipeline 200, respectively. The water quality analyzer is used to detect the pH value of the water, and the conductivity analyzer is used to detect the conductivity of the water. When the detection results of the water quality analyzer and / or conductivity analyzer on the water supply pipeline 300 or the water production pipeline 200 exceed the preset range, the control system 2 issues an alarm. In this embodiment, the preset values ​​of the water quality analyzer and conductivity analyzer on the water production pipeline 200 are higher than the preset values ​​of the water quality analyzer and conductivity analyzer on the water supply pipeline 300.

[0067] In addition, in this embodiment, the discharge rate of the concentrate pipeline 500 is kept between 10% and 30%. A low discharge rate will cause a decline in the quality of the produced water, while a high discharge rate will improve the quality of the produced water but waste water resources. Therefore, the economic discharge rate is between 10% and 30%, which ensures the quality of the produced water while saving water resources.

[0068] S400: Once the drinking water in the production tank 3 reaches the preset storage level, the hollow fiber filter membrane 1 stops producing water.

[0069] In this step, when the drinking water in the water production tank 3 is reduced to the preset storage level, the control system 2 executes step S300.

[0070] S500: After the hollow fiber nanofiltration membrane 1 finishes producing water, the control system 2 opens the forward flushing electric control valve 610 on the forward flushing line 600, keeps the concentrate electric control valve 510 and the product water electric control valve 220 in the open state, and simultaneously closes the electric control valves on other pipelines to perform a forward flushing operation on the hollow fiber nanofiltration membrane 1. In this step, the shut-off valve 320 remains open, and the water in the forward flushing line 600 is drawn from the product water tank 3 using drinking water for forward flushing. The water after forward flushing is discharged through the concentrate line 500.

[0071] In this step, when the control system 2 receives the results from the conductivity detector on the concentrate line 500 and the conductivity detector on the product water line 200 (which indicates that the surface of the hollow fiber nanofiltration membrane 1 in both lines has been cleaned), the forward flushing is stopped and the operation is completed.

[0072] S600: When the hollow fiber nanofiltration membrane 1 reaches the preset flow rate of water, the control system 2 opens the backwash electric control valve 410, keeps the concentrate electric control valve 510 in the open state, and closes the electric control valves on other pipelines to backwash the hollow fiber nanofiltration membrane 1.

[0073] In this step, shut-off valve 320 remains open. The backwash water flow rate inside the hollow fiber nanofiltration membrane 1 is 200-1200 L / H, and the pressure is 2-5 bar. The backwash water flow rate increases with the number of membranes, while the pressure remains constant.

[0074] In this step, when the control system 2 detects that the water filtered by the hollow fiber nanofiltration membrane 1 has reached the threshold, if the water purification equipment is still in a state of frequent use, the control system 2 will record this and postpone the backwashing. When the control system 2 reaches the state of infrequent use of the water purification equipment, the control system 2 will start the backwashing working mode and begin to execute this step. When the control system 2 receives the results of the conductivity detector on the concentrate pipeline 500 and the conductivity detector on the product water pipeline 200, and they are consistent (after consistency, the hollow fiber nanofiltration membrane on the surface is rinsed clean), the backwashing operation is completed.

[0075] Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

Claims

1. An indoor water purification device, characterized in that, The unit includes a housing, with an inlet and an outlet on its side; the housing contains: A pre-filtration system is used to filter particles with a diameter of 20μm-150μm in tap water. The pre-filtration system includes an inlet pipeline, on which an electric inlet control valve, a filter, and an inlet flow meter are sequentially installed. A filtration system is provided to produce drinking water containing minerals. The end of the inlet pipeline is connected to the inlet end located at the bottom of the filtration system. A concentrate pipeline is provided at the top of the filtration system and is connected to the first outlet of the filtration system. The concentrate pipeline discharges the filtered water produced by the filtration system to the outside of the water purification equipment. A concentrate electric control valve is provided on the concentrate pipeline. A water production system is provided for storing drinking water produced by the filtration system. The water production system includes a water production pipeline. The inlet end of the water production pipeline is connected to the second outlet of the filtration system, and the outlet end of the water production pipeline is connected to the water production system. A water production flow meter, a water production electric control valve, and a carbon filter element are sequentially installed on the water production pipeline. The machine casing is equipped with a water supply system, which includes a water supply pipeline. The inlet end of the water supply pipeline is connected to the outlet end of the water production system. A variable frequency water pump and a shut-off valve are sequentially installed on the water supply pipeline, and a water intake is provided at the end of the water supply pipeline. The control system is electrically connected to the inlet electric control valve, the product water electric control valve, the concentrate electric control valve, and the variable frequency water pump.

2. The indoor water purification device according to claim 1, characterized in that, The filtration system is a hollow fiber nanofiltration membrane; the water production system is located in the water production tank.

3. The indoor water purification device according to claim 2, characterized in that, The water production tank is located on the back side inside the casing, while the hollow fiber nanofiltration membrane and the control system are both located in front of the water production tank and arranged side by side.

4. An indoor water purification device according to claim 3, characterized in that, The casing is also equipped with a backwash pipeline. The inlet end of the backwash pipeline is connected to the outlet end of the product water tank, and the outlet end of the backwash pipeline is connected to the second water outlet of the hollow fiber nanofiltration membrane. The backwash pipeline is equipped with a backwash electric control valve, which is electrically connected to the control system. The backwash pipeline is used to balance the water concentration inside the hollow fiber nanofiltration membrane when the water purification equipment is not in operation.

5. An indoor water purification device according to claim 3, characterized in that, The casing is also equipped with a positive flushing pipeline. The inlet end of the positive flushing pipeline is connected to the outlet end of the water production tank, and the outlet end of the positive flushing pipeline is connected to the inlet end of the hollow fiber nanofiltration membrane. A positive flushing electric control valve is installed on the positive flushing pipeline, and the positive flushing electric control valve is electrically connected to the control system. The positive flushing pipeline is used to balance the water concentration inside the hollow fiber nanofiltration membrane when the water purification equipment is not in operation.

6. An indoor water purification device according to claim 3, characterized in that, The casing is also equipped with a venting pipeline. The inlet end of the venting pipeline is connected to the inlet end of the hollow fiber nanofiltration membrane, and the outlet end of the venting pipeline is connected to the concentrate pipeline. The venting pipeline is used to vent the water stored in the hollow fiber nanofiltration membrane, and a venting valve is provided on the venting pipeline.

7. An indoor water purification device according to claim 3, characterized in that, The casing is also equipped with a water discharge pipeline. The inlet end of the water discharge pipeline is connected to the second outlet of the hollow fiber nanofiltration membrane. The water discharge pipeline is equipped with an electric discharge control valve, which is electrically connected to the control system.

8. An indoor water purification device according to claim 3, characterized in that, The casing is also equipped with a return water pipeline. The inlet end of the return water pipeline is connected to the outlet end of the product water tank, and the outlet end of the return water pipeline is connected to the inlet water pipeline. The return water pipeline is used to discharge the water stored in the supply water pipeline into the product water tank, where it is disinfected a second time by an ultraviolet disinfection device inside the product water tank.

9. An indoor water purification device according to claim 3, characterized in that, The casing is also equipped with two pipelines. The inlet end of the two pipelines is connected to the water inlet pipeline, and the outlet end of the two pipelines is connected to the water supply pipeline.

10. An indoor water purification device according to any one of claims 3-9, characterized in that, The hollow fiber nanofiltration membrane has a cylindrical membrane shell.

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