CN222900727U - Can deal with water purification system of abominable water source - Google Patents

Abstract

The utility model discloses a water purification system capable of coping with adverse water sources, comprising a pre-filter element, a membrane filter element, a water pump and a connecting pipeline, the pre-filter element comprising a first water inlet and a water outlet, the first water inlet being connected with a water inlet pipe and a sewage pipe, the water inlet pipe being provided with a first valve, the sewage pipe being provided with a second valve, the membrane filter element comprising a second water inlet, a clean water outlet and a waste water outlet, the clean water outlet being connected with a water storage tank, the inlet of the water pump being connected with the water outlet, the outlet of the water pump being connected with the second water inlet, so as to connect the membrane filter element with the pre-filter element through the connecting pipeline, and the connecting pipeline being provided with a fourth valve, so as to allow the clean water in the water storage tank to flush the membrane filter element and the pre-filter element and discharge them through the sewage pipe when the second valve and the fourth valve are opened, and the clean water backwashing can flush out the impurities and microorganisms intercepted in the pre-filter element, so as to effectively prevent the problem of secondary pollution caused by the reproduction and fermentation of these substances in the filter element.

Description

Can deal with water purification system of abominable water source

Technical Field

The utility model relates to the technical field of water purifiers, in particular to a water purifying system capable of coping with severe water sources.

Background

At present, although the water purifier has been moved into many families, but still faces a lot of difficult problems, generally the water purifier is multi-stage filtration, and raw water first needs to be intercepted by sediment impurity microorganism etc. through the pre-filter element, then is filtered through the membrane filter element, and the purified water or pure water that comes out just can drink directly like this, but in the in-service use of traditional water purifier, can have four pain points:

1. The front filter element is easy to block, and the water quality is slightly poor in areas, so that the front filter element needs to be replaced frequently, and the consumable cost is high and troublesome;

2. The intercepted sediment impurity microorganisms and the like can propagate and ferment in the filter element, so that the filter element can be fishy and smelly after not being used for a long time, secondary pollution is generated, and the water health is affected;

3. After the water purifier is stopped, high-concentration ions on the concentrated water side of the reverse osmosis membrane can permeate to the purified water side, so that water with high ion concentration can be drunk next time, namely so-called aged water, and the water health is affected;

4. For severe water quality, sediment and impurities in water are more, and the front end of the water pump is not protected by the filter element and is easy to fail.

Disclosure of utility model

The utility model aims to provide a water purification system capable of coping with severe water sources, and aims to at least solve one of the technical problems in the prior art.

In order to achieve the above object, the present utility model provides a water purification system capable of coping with severe water source, comprising:

the front filter element comprises a first water inlet and a water outlet, the first water inlet is communicated with a water inlet pipe and a drain pipe, the water inlet pipe is provided with a first valve, and the drain pipe is provided with a second valve;

The membrane filter element comprises a second water inlet, a water purifying port and a waste water port, wherein the water purifying port is communicated with a water storage barrel, and the water storage barrel is used for receiving and storing purified water flowing out of the water purifying port of the membrane filter element;

A water pump, the inlet of the water pump is communicated with the water outlet, the outlet of the water pump is communicated with the second water inlet, and

The communication pipeline is used for communicating the membrane filter element with the preposed filter element through the communication pipeline, and the communication pipeline is provided with a fourth valve;

And when the second valve and the fourth valve are opened, the clean water in the water storage barrel washes the membrane filter core and the preposed filter core and is discharged through the drain pipe.

Further, the valve further comprises a controller, wherein the controller is electrically connected with the first valve, the second valve and the fourth valve respectively, so that the first valve, the second valve and the fourth valve are controlled to be opened or closed through the controller.

Further, the water storage device further comprises a pressure sensor, wherein the pressure sensor is used for detecting the water pressure value in the water storage barrel, so that the controller can control the second valve and the fourth valve to be opened and the first valve to be closed when detecting that the water pressure value in the water storage barrel reaches a preset value according to the pressure sensor.

Further, the water tank further comprises a back flushing pipeline, one end of the back flushing pipeline is communicated with the water purifying port, the other end of the back flushing pipeline is communicated with the waste water port, and the back flushing pipeline is provided with a one-way valve so as to convey the purified water in the water storage barrel to the waste water port of the membrane filter core through the back flushing pipeline, thereby back flushing the membrane filter core and the front filter core and discharging the purified water through the sewage draining pipe.

Further, the waste water treatment device further comprises a waste water pipe, wherein the waste water pipe is communicated with the waste water port, and the waste water pipe is provided with a waste water ratio.

Further, the waste pipe is provided with a third valve.

Further, the water purifying device further comprises a fifth valve, the water purifying port of the membrane filter core is communicated with the water storage barrel through a water purifying pipeline, one end of the back flushing pipeline is communicated with the water purifying port through the water purifying pipeline, the communicating position between one end of the back flushing pipeline and the water purifying pipeline is used as a first junction, the fifth valve is arranged on the water purifying pipeline, and the fifth valve is located between the first junction and the water storage barrel.

Further, the pressure sensor is arranged on the water purifying pipeline, and the pressure sensor is positioned between the fifth valve and the water purifying port.

Further, when the water purification system is in a water production state, the first valve and the third valve are both opened, the second valve and the fourth valve are both closed, and when the water purification system is in a flushing state, the second valve and the fourth valve are both opened, and the first valve and the third valve are both closed.

In addition, the technical scheme of the utility model provides a water purification system capable of coping with severe water sources, which comprises:

the front filter element comprises a first water inlet and a water outlet, the first water inlet is communicated with a water inlet pipe and a drain pipe, the water inlet pipe is provided with a first valve, and the drain pipe is provided with a second valve;

The membrane filter element comprises a second water inlet, a water purifying port and a waste water port, wherein the water purifying port is communicated with a water storage barrel, and the water storage barrel is used for receiving and storing purified water flowing out of the water purifying port of the membrane filter element;

The inlet of the water pump is communicated with the water outlet, and the outlet of the water pump is communicated with the second water inlet;

The communication pipeline is used for communicating the membrane filter element with the preposed filter element through the communication pipeline, and the communication pipeline is provided with a fourth valve;

One end of the back flush pipeline is communicated with the water purifying port, the other end of the back flush pipeline is communicated with the waste water port, and the back flush pipeline is provided with a one-way valve so that the purified water in the water storage barrel flows into the waste water port of the membrane filter element through the back flush pipeline;

One end of the waste water pipe is communicated with the other end of the back flushing pipeline, and the other end of the waste water pipe is provided with a waste water ratio and/or a third valve;

a pressure sensor for detecting a water pressure value in the water storage tub, and

And the controller is respectively and electrically connected with the second valve and the fourth valve, so that the second valve and the fourth valve are controlled to be opened by the controller, and purified water in the water storage barrel is backwashed on the membrane filter core and the preposed filter core and is discharged through the drain pipe.

According to the water purifying system capable of coping with severe water sources, the first water inlet of the front filter element is communicated with the drain pipe, when the membrane filter element and the front filter element are required to be flushed back, the second valve and the fourth valve are opened to enable purified water in the water storage barrel to flush back the membrane filter element, and the purified water flows into the front filter element through the communication pipeline to be backwashed and discharged through the drain pipe, so that impurity microorganisms and the like intercepted in the front filter element can be flushed out without being remained in the filter element, the problem that the filter element is blocked and replaced frequently is solved, the problem that secondary pollution is caused by reproduction and fermentation in the filter element is prevented, and after the purified water is flushed back, the membrane filter element and the front filter element are soaked in the purified water, nutrients can be provided for microorganisms basically, the water health of users can be effectively inhibited, and due to the low ion concentration of the purified water, the high concentration ion crystals adhered on the membrane filter element can be dissolved down, the membrane filter element is prevented from being blocked, the membrane and the filter element is prevented from being damaged by the impurities in the front filter element, and the front filter element is prevented from being damaged by the water pump, and the front filter element is basically damaged, and the filter element is protected.

In order to make the technical conception and other objects, advantages, features and functions of the present utility model more obvious and understandable, preferred embodiments will be described in detail below with reference to the accompanying drawings.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present utility model, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic diagram of a water purification system capable of coping with severe water sources according to an embodiment of the present application.

Wherein the above figures include the following reference numerals:

100. 110 parts of the front filter element, 120 parts of the first water inlet and 120 parts of the water outlet;

200. a membrane cartridge; 210, a second water inlet, 220, a water purifying port, 230, a waste water port;

300. 310, inlet, 320, outlet;

400. a communication pipeline 410, a fourth valve;

500. 510, the second valve;

600. 610, a first valve;

700. Back flushing pipeline, 710, one-way valve, 720, first junction, 730, second junction;

800. Water purifying pipeline 810, water storage barrel 820, pressure sensor 830, fifth valve;

900. waste water pipe 910, waste water ratio 920 and third valve.

Detailed Description

In order that those skilled in the art will better understand the technical solutions of the present utility model, the technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model, and it is apparent that the described embodiments are only some embodiments of the present utility model, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

Referring to fig. 1, the present embodiment provides a water purification system capable of coping with severe water source, comprising:

The front filter element 100 comprises a first water inlet 110 and a water outlet 120, wherein the first water inlet 110 is communicated with a water inlet pipe 600 and a drain pipe 500, the water inlet pipe 600 is provided with a first valve 610, and the drain pipe 500 is provided with a second valve 510;

The membrane filter element 200 comprises a second water inlet 210, a water purifying port 220 and a waste water port 230, wherein the water purifying port 220 is communicated with a water storage bucket 810, and the water storage bucket 810 is used for receiving and storing purified water flowing out of the water purifying port 220 of the membrane filter element 200;

A water pump 300, an inlet 310 of the water pump 300 being communicated with the water outlet 120, an outlet 320 of the water pump 300 being communicated with the second water inlet 210, the water pump 300 being located between the pre-filter cartridge 100 and the membrane filter cartridge 200, and

A communication pipe 400 to communicate the membrane cartridge 200 with the pre-cartridge 100 through the communication pipe 400, and the communication pipe 400 is provided with a fourth valve 410;

Wherein, the membrane cartridge 200 and the pre-cartridge 100 are backwashed with the purified water in the water storage tub 810 when the second valve 510 and the fourth valve 410 are opened and discharged outside of the water purification system through the drain pipe 500, thereby implementing the backwash of the membrane cartridge 200 and the pre-cartridge 100 with the purified water.

It can be seen that, in the water purification system capable of coping with severe water sources of this embodiment, through the drain pipe 500 communicated with the first water inlet 110 of the pre-filter element 100, when the membrane filter element 200 and the pre-filter element 100 need to be back-flushed, the second valve 510 and the fourth valve 410 are opened to enable the purified water in the water storage barrel 810 to back-flush the membrane filter element 200, and the water flows into the pre-filter element 100 through the communication pipeline 400 to be back-flushed and discharged through the drain pipe 500, the purified water back-flushing can flush out the impurity microorganisms and the like intercepted in the pre-filter element 100, but not remain in the filter element, the problem that the filter element is blocked and replaced frequently is solved, the problem that secondary pollution is caused by propagation and fermentation in the filter element is prevented, and after the back-flushing of the purified water is finished, the membrane filter element 200 and the pre-filter element 100 are soaked in the purified water, the purity of the purified water is high, the microorganism can not be provided with nutrients basically, the microorganism breeding can be effectively inhibited, the water health of users is guaranteed, and the ion concentration of the purified water is low, the membrane 200 can be further lifted to have high concentration of the crystal attached to the membrane filter element, the filter element is prevented from being blocked by the membrane 200, and the severe water source is prevented from being damaged by the pre-filter element 300, and the filter element is prevented from being blocked by the water source, and the filter element is protected.

In this embodiment, as shown in fig. 1, the water purification system further includes a controller electrically connected to the first valve 610, the second valve 510 and the fourth valve 410, respectively, so that the first valve 610, the second valve 510 and the fourth valve 410 are controlled to be opened or closed by the controller, when the water purification system produces water, the first valve 610 and the water pump 300 are opened, the second valve 510 and the fourth valve 410 are closed, and when the water purification is backflushed, the first valve 610 and the water pump 300 are closed, the second valve 510 and the fourth valve 410 are opened, so that the membrane filter cartridge 200 and the pre-filter cartridge 100 are backflushed and discharged through the drain pipe 500.

Wherein, alternatively, the first valve 610, the second valve 510 and the fourth valve 410 may all be solenoid valves.

Specifically, as shown in fig. 1, the water purification system further includes a pressure sensor 820 for detecting a water pressure value in the water storage tub 810, such that the controller controls the second valve 510 and the fourth valve 410 to be opened and the first valve 610 and the water pump 300 to be closed according to the detection of the water pressure value in the water storage tub 810 by the pressure sensor 820 to backwash the membrane cartridge 200 and the pre-cartridge 100 and discharge the water purification system outside through the drain pipe 500.

Further, as shown in fig. 1, the water purification system further includes a back flush line 700, one end of the back flush line 700 is communicated with the water purification port 220, the other end thereof is communicated with the water discharge port 230, and the back flush line 700 is provided with a check valve 710 to deliver purified water in the water storage tub 810 to the water discharge port 230 of the membrane cartridge 200 through the back flush line 700, thereby back flushing the membrane cartridge 200 and the pre-cartridge 100 and discharging the same through the drain pipe 500.

In this embodiment, as shown in fig. 1, the water purification system further includes a waste pipe 900, the waste pipe 900 is communicated with the waste water port 230, and the waste pipe 900 is provided with a waste water ratio 910, the waste water ratio 910 being a waste water proportional valve for adjusting the waste water discharge amount.

Specifically, as shown in fig. 1, the waste pipe 900 is provided with a third valve 920, and the third valve 920 may be an electromagnetic valve, and when the water purifier produces water, the controller controls the third valve 920 to be opened so that the waste water in the membrane filter cartridge 200 is discharged through the waste pipe 900.

Further, as shown in fig. 1, the water purification system further includes a fifth valve 830, the water purifying port 220 of the membrane filter element 200 is communicated with the water storage tank 810 through the water purifying pipeline 800, one end of the back flushing pipeline 700 is communicated with the water purifying port 220 through the water purifying pipeline 800, the communicating position between one end of the back flushing pipeline 700 and the water purifying pipeline 800 is used as the first junction 720, the fifth valve 830 is disposed on the water purifying pipeline 800, and the fifth valve 830 is located between the first junction 720 and the water storage tank 810, wherein the fifth valve 830 can adopt an electromagnetic valve, and when the water purification system produces water, the controller controls the fifth valve 830 to be opened, so that the purified water flowing out of the water purifying port 220 of the membrane filter element 200 flows into the water storage tank 810 through the water purifying pipeline 800 for storage.

In this embodiment, as shown in fig. 1, the other end of the backwash pipeline 700 is communicated with the waste gate 230 through the waste pipe 900, and a communication position between the other end of the backwash pipeline 700 and the waste pipe 900 is taken as a second junction 730, the second junction 730 is located between the waste gate 230 and the waste water ratio 910, and as an alternative embodiment, the third valve 920 is disposed between the second junction 730 and the waste water ratio 910 or the waste water ratio 910 is disposed between the second junction 730 and the third valve 920.

Specifically, as shown in fig. 1, a pressure sensor 820 is provided on the water purifying pipe 800, and the pressure sensor 820 is located between the fifth valve 830 and the water purifying port 220.

Further, as shown in fig. 1, when the water purification system is in a water producing state, the first valve 610, the third valve 920 and the water pump 300 are all opened, the second valve 510 and the fourth valve 410 are all closed, and when the water purification system is in a flushing state, the second valve 510 and the fourth valve 410 are all opened, and the first valve 610, the third valve 920 and the water pump 300 are all closed.

As shown in fig. 1, when the water purification system produces water, the controller controls the first valve 610, the third valve 920 and the fifth valve 830 to be opened, the water pump 300 is started, raw water flows into the pre-filter cartridge 100 through the water inlet pipe 600 to be filtered, then flows into the membrane filter cartridge 200 after being pressurized by the water pump 300, purified water filtered by the membrane filter cartridge 200 flows into the water storage barrel 810 through the purified water pipeline 800 to be stored for daily use by a user, waste water in the membrane filter cartridge 200 is discharged through the waste water pipe 900, the pressure of the waste water is generally greater than the pressure of the purified water, but the back flushing pipeline 700 is provided with the one-way valve 710, so that the waste water does not flow into the purified water pipeline 800 through the back flushing pipeline 700, the water storage barrel 810 gradually rises along with the injection pressure of the purified water, when the pressure sensor 820 detects that the pressure of the water storage barrel 810 reaches a preset value, the controller controls the first valve 610, the third valve 920 and the water pump 300 to be closed, the second valve 510 and the fourth valve 410 to be opened, at this time, purified water in the water storage barrel 810 flows into the membrane filter core 200 through the purified water port 220 and the waste water port 230 respectively in two ways to be backwashed, the membrane filter core 200 is simultaneously washed in two directions, residues on the membrane filter core 200 can be well stripped, membrane blockage is prevented, the flushing effect of the membrane filter core 200 is effectively improved, then the purified water flows into the pre-filter core 100 through the communication pipeline 400 to be backwashed and is discharged out of the water purification system through the drain pipe 500, sediment impurity microorganisms intercepted in the pre-filter core 100 and old water in the membrane filter core 200 can be discharged through the drain pipe 500 in the whole purified water backwash process, the second valve 510 and the fourth valve 410 are controlled to be closed after the water pressure of the water storage barrel 810 reaches the preset condition, the purified water backwash is stopped, at this time, the pre-cartridge 100 and the membrane cartridge 200 are completely soaked with the purified water, and the remaining purified water in the water storage tub 810 is available for the user's daily life.

From the above description, it can be seen that the above embodiments of the present utility model achieve the following technical effects:

According to the water purification system capable of coping with a severe water source, the first water inlet 110 of the front filter element 100 is communicated with the drain pipe 500, when the membrane filter element 200 and the front filter element 100 are required to be backwashed, the second valve 510 and the fourth valve 410 are opened, so that the membrane filter element 200 is backwashed by clean water in the water storage barrel 810, and the clean water flows into the front filter element 100 through the communication pipeline 400 to be backwashed and discharged through the drain pipe 500, so that the clean water backwashed can wash out impurity microorganisms and the like intercepted in the front filter element 100 without being remained in the filter element, the problem that the filter element is blocked and replaced frequently is solved, the problem that secondary pollution is caused by reproduction and fermentation in the filter element is prevented, and after the clean water backwashed is finished, the membrane filter element 200 and the front filter element 100 are soaked in the clean water, the clean water is basically free from providing nutrients for microorganisms, the clean water can be effectively inhibited from growing, and the clean water of users is ensured.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the present application. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.

The relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present application unless it is specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective parts shown in the drawings are not drawn in actual scale for convenience of description. Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail, but should be considered part of the specification where appropriate. In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of the exemplary embodiments may have different values.

It should be noted that, in the description of the present application, unless explicitly stated or limited otherwise, the terms "disposed, connected, and communicated" should be construed broadly, and may be, for example, fixedly connected, detachably connected, or connected in an abutting or integral manner, or may be directly connected or indirectly connected through an intermediate medium, and it will be understood that the specific meaning of the terms in the present application will be specifically understood by those skilled in the art.

In addition, in the description of the present utility model, the terms "first" and "second" are used to define the components, and are only used to facilitate distinguishing between the corresponding components, and the terms have no special meaning unless otherwise stated, and therefore should not be construed as limiting the scope of the present utility model.

While the foregoing is directed to the preferred embodiments of the present utility model, it will be appreciated by those skilled in the art that changes and modifications may be made without departing from the principles of the utility model, such changes and modifications are also intended to be within the scope of the utility model.

Claims (10)

1. A water purification system capable of coping with severe water sources, comprising:

the front filter element comprises a first water inlet and a water outlet, the first water inlet is communicated with a water inlet pipe and a drain pipe, the water inlet pipe is provided with a first valve, and the drain pipe is provided with a second valve;

The membrane filter element comprises a second water inlet, a water purifying port and a waste water port, wherein the water purifying port is communicated with a water storage barrel, and the water storage barrel is used for receiving and storing purified water flowing out of the water purifying port of the membrane filter element;

A water pump, the inlet of the water pump is communicated with the water outlet, the outlet of the water pump is communicated with the second water inlet, and

The communication pipeline is used for communicating the membrane filter element with the preposed filter element through the communication pipeline, and the communication pipeline is provided with a fourth valve;

And when the second valve and the fourth valve are opened, the clean water in the water storage barrel washes the membrane filter core and the preposed filter core and is discharged through the drain pipe.

2. The system of claim 1, further comprising a controller electrically connected to the first, second and fourth valves, respectively, for controlling the first, second and fourth valves to open or close by the controller.

3. The system of claim 2, further comprising a pressure sensor for detecting a water pressure in the water storage tank, such that the controller controls the second and fourth valves to be opened and the first valve to be closed when the pressure sensor detects that the water pressure in the water storage tank reaches a preset value.

4. A water purification system capable of coping with a severe water source according to claim 3, further comprising a back flush line, one end of the back flush line being in communication with the water purification port and the other end thereof being in communication with the waste water port, and the back flush line being provided with a one-way valve to convey the purified water in the water storage tub to the waste water port of the membrane filter cartridge through the back flush line, thereby back flushing the membrane filter cartridge and the pre-filter cartridge and discharging the purified water through the drain pipe.

5. The system of claim 4, further comprising a waste pipe in communication with the waste port, the waste pipe being provided with a waste to water ratio.

6. The system according to claim 5, wherein the waste pipe is provided with a third valve.

7. The system of claim 6, further comprising a fifth valve, wherein the water purifying port of the membrane filter is communicated with the water storage tank through a water purifying pipeline, one end of the back flushing pipeline is communicated with the water purifying port through the water purifying pipeline, a communication position between one end of the back flushing pipeline and the water purifying pipeline is used as a first junction, the fifth valve is disposed on the water purifying pipeline, and the fifth valve is disposed between the first junction and the water storage tank.

8. The system according to claim 7, wherein the pressure sensor is disposed on the water purifying pipe and is located between the fifth valve and the water purifying port.

9. The system of claim 7, wherein the first valve and the third valve are both opened and the second valve and the fourth valve are both closed when the system is in a water-producing state, and wherein the second valve and the fourth valve are both opened and the first valve and the third valve are both closed when the system is in a flushing state.

10. A water purification system capable of coping with severe water sources, comprising:

the front filter element comprises a first water inlet and a water outlet, the first water inlet is communicated with a water inlet pipe and a drain pipe, the water inlet pipe is provided with a first valve, and the drain pipe is provided with a second valve;

The membrane filter element comprises a second water inlet, a water purifying port and a waste water port, wherein the water purifying port is communicated with a water storage barrel, and the water storage barrel is used for receiving and storing purified water flowing out of the water purifying port of the membrane filter element;

The inlet of the water pump is communicated with the water outlet, and the outlet of the water pump is communicated with the second water inlet;

The communication pipeline is used for communicating the membrane filter element with the preposed filter element through the communication pipeline, and the communication pipeline is provided with a fourth valve;

One end of the back flush pipeline is communicated with the water purifying port, the other end of the back flush pipeline is communicated with the waste water port, and the back flush pipeline is provided with a one-way valve so that the purified water in the water storage barrel flows into the waste water port of the membrane filter element through the back flush pipeline;

One end of the waste water pipe is communicated with the other end of the back flushing pipeline, and the other end of the waste water pipe is provided with a waste water ratio and/or a third valve;

a pressure sensor for detecting a water pressure value in the water storage tub, and

And the controller is respectively and electrically connected with the second valve and the fourth valve, so that the second valve and the fourth valve are controlled to be opened by the controller, and purified water in the water storage barrel is backwashed on the membrane filter core and the preposed filter core and is discharged through the drain pipe.