CN212548464U - Duplex filter - Google Patents

Abstract

The present application relates to a duplex filter comprising: two filters; the liquid outlet of the buffer tank is connected with the liquid inlet end of the liquid inlet pipe, and the buffer tank is provided with a foam overflow port for discharging foam, a cleaning port for introducing cleaning liquid and a liquid level detector for detecting the liquid level inside; the liquid outlet of buffer tank is equipped with the valve that can open or close according to the level detection meter signal. The utility model has the advantages that: the two filters can be switched to clean, so that the phenomenon that the machine is stopped due to blockage of medicine residues is avoided; the buffer tank of setting has been avoided bringing the no-load problem of filter liquid pump because of centrifuge goes out the liquid velocity of flow unstability, and the buffer tank is given the liquid pump and is restarted and reserve the buffer time, has solved the problem that the foam got into the excessive foam of filter effectively, and the problem of the not enough discharge of filter buffer when also effectual solution centrifuge washs simultaneously.

Description

Duplex filter

Technical Field

The application belongs to the technical field of filters, and particularly relates to a duplex filter.

Background

The duplex switching filter is characterized in that two single-cylinder filters are assembled on one machine base, and the two single-cylinder filters are switched and cleaned, so that continuous filtration can be ensured, the machine does not need to be stopped, and the non-stop conversion and cleaning can be realized.

In the prior art, the no-load problem of a filter liquid outlet pump caused by unstable liquid outlet flow rate of a centrifugal machine, the conditions of flow break, overflow, foam and the like of a duplex filter occur, and simultaneously, the foam is easily formed due to secondary impact before liquid medicine enters the filter.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is: the duplex filter is provided for solving the problems of cutoff, overflow, foam generation and the like of the duplex filter in the prior art.

The utility model provides a technical scheme that its technical problem adopted is:

a duplex filter comprising:

the liquid inlet ends of the two filters are connected with a liquid inlet pipe through a first three-way pipe, and the liquid outlet ends of the two filters are connected with a liquid outlet pipe through a second three-way pipe; the bottoms of the two filters are respectively provided with a sewage discharge outlet, the tops of the two filters are respectively provided with a cleaning port, the inner cavity of each filter is provided with a filter screen and a spraying ball, and the spraying balls are connected with the cleaning ports;

the liquid outlet of the buffer tank is connected with the liquid inlet end of the liquid inlet pipe, and the buffer tank is provided with a foam overflow port for discharging foam, a cleaning port for introducing cleaning liquid and a liquid level detector for detecting the liquid level inside; and a liquid outlet of the buffer tank is provided with a valve which can be opened or closed according to the signal of the liquid level detection meter.

Preferably, the utility model discloses a pair of filter, first three-way pipe is connected to two through first mouth of pipe and second mouth of pipe respectively inside the filter, first mouth of pipe and second mouth of pipe orientation with the inner wall of filter becomes acute angle of incidence.

Preferably, the utility model discloses a duplex filter, feed liquor pipe department is equipped with the feed liquor valve, the below of feed liquor valve is equipped with the blowback mouth that is used for utilizing compressed air to blow off the dregs of a decoction.

Preferably, the utility model discloses a duplex filter, drain pipe department is equipped with sight glass, sample connection, and sample connection department sets up the sample valve.

Preferably, the utility model discloses a duplex filter, drain pipe department is equipped with the pipe-line filter, and the pipe-line filter below is equipped with the discharge port that is used for discharging the dregs of a decoction, and discharge port department sets up the hand valve.

Preferably, the utility model discloses a pair filter, pipeline filter's rear end is equipped with the electromagnetic flowmeter.

Preferably, the utility model discloses a pair of filter, spray the ball lead to pipe with the washing mouth is connected, arranges along the circumference spray the ball total three, adjacent arrange along the circumference spray the ball about the axis of filter becomes the rotational symmetry of degree contained angle and arranges.

Preferably, the utility model discloses a duplex filter, the filter screen includes: the filter screen comprises a filter screen main body and a filter screen frame, wherein the filter screen main body is vertically fixed and clamped on the filter screen frame by adopting a hoop.

Preferably, the duplex filter of the present invention, one side of the filter is provided with an eyepiece.

Preferably, the utility model discloses a pair filter, the top of filter is equipped with magnetic levitation ball level switch.

The utility model has the advantages that: the two filters can be switched to clean, so that the phenomenon that the machine is stopped due to blockage of medicine residues is avoided; the buffer tank of setting has been avoided bringing the no-load problem of filter liquid pump because of centrifuge goes out the liquid velocity of flow unstability, and the buffer tank is given the liquid pump and is restarted and reserve the buffer time, has solved the problem that the foam got into the excessive foam of filter effectively, and the problem of the not enough discharge of filter buffer when also effectual solution centrifuge washs simultaneously.

Drawings

The technical solution of the present application is further explained below with reference to the drawings and the embodiments.

FIG. 1 is a schematic diagram of a filter inlet and outlet structure of a duplex filter according to an embodiment of the present disclosure;

FIG. 2 is a schematic view of a surge tank structure of a duplex strainer according to an embodiment of the present disclosure;

fig. 3 is a schematic diagram of a screen structure of a duplex strainer according to an embodiment of the present disclosure.

The reference numbers in the figures are:

1 Filter

2 liquid inlet pipe

3 liquid outlet pipe

4 buffer tank

5 Pump

10 first three-way pipe

11 sewage draining outlet

12 cleaning opening

13 filter screen

14 spray ball

15 second three-way pipe

16 vent

17 floating ball mounting port

21 liquid inlet valve

32 view mirror

33 sampling port

34 pipeline filter

41 foam overflow port

42 cleaning liquid inlet

43 liquid level detecting meter

44 shock absorber

101 first nozzle

102 second nozzle

131 filter screen main body

132 a strainer tray.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

In the description of the present application, it is to be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the orientation or positional relationship indicated in the drawings for convenience in describing the present application and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated in a particular manner, and are not to be considered limiting of the scope of the present application. Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the invention, unless otherwise specified, "a plurality" means two or more.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art through specific situations.

In this embodiment, the term "front" and "rear" means that the liquid inlet side is front and the liquid outlet side is rear when the liquid medicine flows.

The technical solutions of the present application will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

Examples

The present embodiment provides a duplex filter, as shown in fig. 1-3, comprising:

the liquid inlet ends of the two filters 1 are connected with a liquid inlet pipe 2 through a first three-way pipe 10, and the liquid outlet ends of the two filters 1 are connected with a liquid outlet pipe 3 through a second three-way pipe 15; the bottoms of the two filters 1 are respectively provided with a sewage discharge outlet 11, the tops of the two filters are respectively provided with a cleaning port 12, the inner cavity of each filter is provided with a filter screen 13 and a spray ball 14, and the spray balls 14 are connected with the cleaning ports 12;

the liquid outlet of the buffer tank 4 is connected to the liquid inlet end of the liquid inlet pipe 2, and the buffer tank 4 is provided with a foam overflow port 41 for discharging foam, a cleaning liquid inlet 42 for introducing cleaning liquid and a liquid level detector 43 for detecting the internal liquid level; the liquid outlet of the buffer tank 4 is provided with a valve which can be opened or closed according to the signal of the liquid level detection meter 43.

The duplex filter of the embodiment deals with the situations of flow break, overflow, foam and the like of the duplex filter, the buffer tank 4 is added above the two filters 1, and the buffer tank 4 has certain capacity, so that the problem of insufficient buffer of the filter and overflow during the cleaning of the centrifuge is effectively solved; the liquid level detector 43 and the associated valve are matched to feed liquid and discharge liquid at intervals, so that the problem of no-load of a liquid discharge pump of a filter caused by unstable liquid discharge flow rate of a centrifugal machine is avoided, and buffer time is reserved for restarting the liquid discharge pump; the buffer tank 4 is provided with a foam overflow port 41 for discharging foam, thereby effectively solving the problem that the foam enters the filter 1 and overflows.

In a specific embodiment, the buffer tank 4 is provided with three liquid levels, namely a high liquid level, a low liquid level and a medium liquid level, the liquid outlet valve is opened when the liquid level of the buffer tank 4 reaches the medium level, the liquid outlet pump is started after a delay of 15S, the liquid outlet valve is closed when the liquid level of the buffer tank is lower than the low liquid level, and the liquid outlet pump is stopped after a delay of 10S; the procedure was repeated until a medium level was reached. By the control method, the problem of no load of the liquid outlet pump of the filter caused by unstable liquid outlet flow rate of the centrifugal machine can be avoided.

According to the duplex filter, the two filters can be switched to be cleaned, and the phenomenon that the machine is stopped due to blockage of medicine dregs is avoided.

The duplex filter of the present embodiment, as shown in particular in figure 1,

(1) the cleaning opening 12 is respectively provided with an automatic ball valve, a manual ball valve is added on a public pipeline to prevent accidents, the cleaning pipeline and the upper cover of the filter 1 are fixed together by a chuck and extend to the bottom, the left and the right spray balls 14 are three, and the lower spray ball 14 can be fully sprayed to the periphery to clean the inner cavity.

(2) The top of the filter 1 is provided with a vent 16, manual ball valves are respectively added on the vent 16, and the valve of the vent 16 is always opened in the production process to prevent pressurized liquid medicine from entering.

(3) A liquid inlet three-way switching valve is arranged on the first three-way pipe 10, a duplex filter liquid inlet pneumatic ball valve and a manual ball valve are respectively arranged above the liquid inlet three-way switching valve, the pneumatic ball valve controls liquid outlet, and the manual ball valve adjusts liquid inlet flow; a back-flushing opening (manual ball valve) is added below the liquid inlet valve, and when the liquid inlet pipeline is blocked by the dregs of a decoction, the liquid inlet pipeline is subjected to back flushing and dredging by utilizing compressed air.

(4) A left and right double outer cavity blowoff valve is arranged at the blowoff port 11 to discharge all the filtered dregs.

(5) The second three-way pipe 15 is provided with a liquid outlet three-way switching valve, a pipeline is respectively added between the left and right double liquid outlets and the switching valve and connected to the outer cavity for sewage disposal, meanwhile, a pneumatic ball valve is added on the pipeline to be used as an inner cavity sewage disposal valve, when the double filter is automatically cleaned, the inner cavity sewage disposal valve and the outer cavity sewage disposal valve are opened simultaneously, and the slag liquid in the tank is ensured to be thoroughly discharged and wait for cleaning. A sight glass and a sampling valve are added behind the liquid outlet valve, so that whether liquid medicine flows in the liquid outlet or not and liquid medicine samples are collected conveniently.

(6) Increase the main line blowdown between drain pipe 3 and liquid outlet pump, increase pneumatic ball valve as the trunk line blowoff valve on the pipeline, wash each pipeline when being convenient for clear yard, the blowdown.

(7) The liquid outlet adopts a delivery pump to deliver the liquid medicine into a storage tank.

(8) The upper cover of the duplex filter 1 can be detached, so that the filter screen 13 in the inner cavity can be conveniently taken out for replacement, and a sealing ring is respectively added between the upper cover and the tank opening and is fixedly sealed by a plurality of hinges. The shell of the filter is provided with a circle of ultrasonic vibrators, and the ultrasonic vibrators are wrapped and protected by a layer of stainless steel iron sheet so as not to be exposed.

Preferably, in the duplex filter of the present embodiment, the first tee 10 is connected to the insides of two of the filters 1 through a first nozzle 101 and a second nozzle 102, respectively, and the first nozzle 101 and the second nozzle 102 face an acute angle of incidence with the inner wall of the filters 1. Before the liquid medicine in the buffer tank 4 enters the filter 1, an acute angle (preferably 45-degree slope pipeline) is adopted, so that the liquid medicine is prevented from being impacted for the second time to form foam. In a specific embodiment, the first nozzle 101 and the second nozzle 102 have elliptical apertures, which substantially disperse the incoming liquid, reducing direct impact on the lumen screen.

Preferably, in the duplex filter of this embodiment, a liquid inlet valve 21 is disposed at the liquid inlet pipe 2, and a back-flushing port for blowing away the dregs by using compressed air is disposed below the liquid inlet valve 21. When the liquid inlet pipeline is blocked by the dregs of a decoction, the liquid inlet pipeline is subjected to back flushing and dredging by utilizing compressed air.

Preferably, in the duplex filter of the present embodiment, the liquid outlet pipe 3 is provided with a viewing mirror 32 and a sampling port 33, and the sampling port 33 is provided with a sampling valve. It is convenient to observe whether the liquid medicine flows and collect the liquid medicine sample.

Preferably, in the duplex filter of this embodiment, as shown in fig. 1, a pipeline filter 34 is disposed at the liquid outlet pipe 3, a discharge port for discharging medicine residues is disposed below the pipeline filter, and a hand valve is disposed at the discharge port. As shown in figure 1, a pipeline filter 34 is added behind the pump 5 for judging whether the filter screen of the inner cavity is damaged, and a hand valve is added below the pipeline filter 34 for conveniently discharging medicine dregs in the pipeline filter.

Preferably, the duplex filter of the present embodiment, as shown in fig. 1, is provided with an electromagnetic flow meter at the rear end of the pipe filter 34. The device is used for measuring the flow rate and the accumulation amount of liquid medicine outflow and judging whether the duplex filter is blocked or not in the automatic liquid outflow process according to the flow rate.

Preferably, in the duplex filter of the present embodiment, as shown in fig. 3, the spraying balls 14 are connected to the cleaning opening 12 through water pipes, the number of the spraying balls 14 arranged along the circumference is three, and the adjacent spraying balls 14 arranged along the circumference are rotationally symmetrically arranged with an included angle of 120 degrees with respect to the axis of the filter 1.

Preferably, in the duplex filter of the present embodiment, as shown in fig. 3, the filter mesh 13 includes: filter screen main part 131, filter screen frame 132, filter screen main part 131 adopts the staple bolt to fix the chucking from top to bottom on the filter screen frame 132. Specifically, a single-layer 150-mesh stainless steel filter screen can be used for filtering the liquid medicine, and the filter screen belongs to a consumable product and needs to be replaced irregularly due to time and the reason that the filter screen blocks up pressure and impact force caused by the liquid medicine on the filter screen. The filter screen adopts the staple bolt to fix the chucking on the filter screen frame from top to bottom, and the position of fixed filter screen has the pressure groove, because of staple bolt and filter screen support are all harder, for avoiding filter screen and its unnecessary loss that wearing and tearing caused, adds the round silica gel pad between filter screen and staple bolt and protects. The screen frame 132 is in a grid shape, pressure on the screen is reduced, and the support is made of alloy, firm, light and easy to detach. The liquid outlet end of the filter 1 is provided with a liquid outlet male head and a liquid outlet female head at the joint of the liquid outlet end and the pipeline, the difference between the outer diameter of the male head and the inner diameter of the female head is 3mm, three grooves with the diameter of 1.5mm are arranged on the male head, and a leather ring with the diameter of 3mm is sleeved on the male head, so that the design is to prevent the liquid medicine from directly entering the liquid outlet pipeline from the outer cavity (the outer side of the.

Preferably, in the duplex filter of the present embodiment, an eyepiece is provided at one side of the filter 1. The front surface of the filter 1 is provided with an ocular lens, so that the basic conditions (liquid level, the cleaning degree of a filter screen and the like) in the duplex filter can be visually observed.

Preferably, in the duplex filter of the present embodiment, a magnetic float ball liquid level switch is disposed at the top of the filter 1. As shown in figure 1, a magnetic floating ball liquid level switch with the length of 600mm is respectively arranged at the floating ball mounting port 17, when the liquid level reaches the floating ball, the floating ball floats with a signal, the dual liquid inlet valve can be automatically closed, and the liquid medicine is prevented from overflowing from the emptying port when the tank is full.

Preferably, the duplex filter of the present embodiment, as shown in fig. 2, has a shock absorber 44 at the connection between the buffer tank 4 and the centrifuge. The vibration damper 44 is used to damp the vibration transmitted from the centrifuge to the surge tank 4.

The present embodiment provides the above-described operating protocol for the duplex filter:

initial state:

1. the duplex filter is in a manual state, the corresponding automatic control valves (the liquid inlet pipeline automatic control valve, the duplex filter cleaning valve and the blow-down valve) and the motor are all in a closed state, and the hand valves (except the back flushing port valve) of the duplex filter are all in an open state.

2. The filter screen of the duplex filter meets the filtering condition (the cleanness degree of the filter screen is observed from a sight glass port), and the buffer tank has no slag liquid.

Liquid outlet flow:

firstly, before liquid discharge:

1. before the liquid is discharged from the extraction tank, the centrifugal machine is started 10 minutes in advance, and the liquid is discharged after the centrifugal machine operates stably.

2. After the centrifuge runs stably and meets the liquid outlet condition, the duplex filter is put into a self-control state: clicking 'duplex automatic control', popping up a 'duplex automatic control' window, clicking 'automatic cutting' popping up 'to confirm that the window is put into the automatic' window, clicking 'yes', and duplex entering an automatic state.

3. After the duplex enters an automatic state, opening a valve from liquid outlet to a centrifugal machine to start normal liquid outlet.

II, discharging liquid:

1. after the liquid level of the buffer tank is slowly raised to the middle liquid level, automatically opening a duplex liquid inlet pipeline automatic control valve, and starting to feed liquid by using a duplex filter; the liquid outlet pump starts timing after the automatic control valve of the duplex liquid inlet pipeline is opened, and the liquid outlet pump is automatically started after the time for starting the pump is delayed to start to pump liquid into the storage tank.

2. In the normal liquid discharging process, after the automatic control valve of the duplex liquid inlet pipeline is opened, the liquid level of the buffer tank can be lowered to be lower than the middle liquid level; and after the liquid level of the buffer tank is lower than the low liquid level, the automatic control valve of the duplex liquid inlet pipeline is automatically closed. At the moment, the buffer tank normally feeds liquid, the liquid outlet pump normally operates, after the liquid level of the buffer tank reaches the medium liquid level, the duplex liquid inlet pipeline automatic control valve is opened again, liquid inlet is started in duplex mode, and the circulation is repeated.

3. When the liquid level of the duplex filter is too high, the floating ball liquid level switch is triggered to be switched on, and the duplex liquid inlet pipeline automatic control valve is automatically closed; if the liquid outlet flow rate is larger than the judging blockage flow value, the liquid outlet pump normally operates, and if the liquid outlet flow rate is lower than the judging blockage flow value, the liquid outlet pump is immediately restarted; when the liquid level of the duplex filter is reduced, the float ball liquid level switch signal disappears, and after the liquid level of the buffer tank reaches the middle liquid level, the duplex liquid inlet pipeline automatic control valve is automatically opened, so that the circulation is repeated.

4. After the liquid outlet pump is firstly higher than 5000, when the flow rate is lower than 500 and kept for 3 seconds, the liquid outlet pump is judged to be evacuated, the liquid cannot be pumped normally, the liquid outlet pump is automatically closed, and the rest steps refer to the step 1.

5. And (3) judging and blocking conditions of duplex switching:

the liquid level of the buffer tank reaches the middle liquid level and above;

secondly, the liquid outlet pump is in an open state;

and thirdly, the effluent flow rate is lower than the judging and blocking flow value and is kept for 15 seconds.

And when the three conditions are simultaneously met, duplex automatic switching is performed.

6. After duplex blockage judgment is switched, the liquid outlet pump is automatically closed, liquid medicine enters the duplex on the other side, the pump starts to be started after the duplex-cutting pump-stopping time is met, and the blockage judgment condition is the same as the above. Meanwhile, the duplex on the blockage judging side starts to be automatically cleaned, and can be used for next blockage judging switching after cleaning is finished; if the duplex on one side meets the blockage judging condition during the cleaning process and the duplex on the other side meets the blockage judging condition, the duplex filter judges the whole blockage, the duplex liquid inlet pipeline automatic control valve is automatically closed, liquid is discharged to the centrifugal machine valve to stop discharging, the liquid is recovered after one side is cleaned, and the other side starts automatic cleaning.

Thirdly, after liquid is discharged:

1. duplex automatic cleaning: after liquid discharge is finished, the liquid level of the buffer tank is lower than the low liquid level, the liquid discharge pump is evacuated, the automatic control valve of the duplex liquid inlet pipeline and the liquid discharge pump can be automatically closed, the duplex is still in an automatic state, a mouse clicks to press left cleaning or right cleaning for a long time, and when a button turns green and then is loosened, the duplex filter starts automatic cleaning. Can only be cleaned one by one and does not support simultaneous cleaning.

2. Automatic cleaning process: the blowdown valve (outer cavity + inner cavity) is opened automatically and is kept normally open state all the time in the cleaning process (at this moment, in order to protect the blowdown pipeline not to be scalded by high-temperature liquid medicine, the 8-line cleaning valve is opened by force and is kept normally open state all the time along with the opening of 7-line blowdown). Opening the cleaning valve 30 seconds later (ensuring no liquid in the duplex filter), closing the cleaning valve 5 seconds later, and opening the cleaning valve again 25 seconds later; the process is circulated for five times, and then the drain valve is closed. The same is true for the automatic cleaning step during dual block judgment switching.

3. After the left and right sides are cleaned in duplex mode, the duplex filter is switched back to manual mode.

4. After stopping centrifuge 30 ~ 40 minutes, centrifuge stopping steady and to have in many sediment liquid discharges advance the buffer tank, needs field personnel (centrifuge stopping steady and not having sound) or well accuse personnel (looking over buffer tank liquid level and rising) to observe, at this moment manually opens pair blowoff valve (advance which pair just opens which blowdown), then opens pair inlet conduit automatic control valve, drains the sediment in the buffer tank to open the purge valve of buffer tank and ensure that the buffer tank is clean. After the buffer tank is drained completely, the duplex liquid inlet pipeline automatic control valve and the duplex blowdown valve are closed, the duplex filter is switched to an automatic state, then the duplex filter is automatically cleaned, and after the duplex filter is cleaned, the duplex filter is switched back to a manual state.

In light of the foregoing description of the preferred embodiments according to the present application, it is to be understood that various changes and modifications may be made without departing from the spirit and scope of the invention. The technical scope of the present application is not limited to the contents of the specification, and must be determined according to the scope of the claims.

Claims (10)

1. A duplex filter, comprising:

the liquid inlet ends of the two filters (1) are connected with the liquid inlet pipe (2) through a first three-way pipe (10), and the liquid outlet ends of the two filters (1) are connected with the liquid outlet pipe (3) through a second three-way pipe (15); the bottoms of the two filters (1) are respectively provided with a sewage outlet (11), the tops of the two filters are respectively provided with a cleaning port (12), the inner cavity of each filter is provided with a filter screen (13) and a spray ball (14), and the spray balls (14) are connected with the cleaning ports (12);

the liquid outlet of the buffer tank (4) is connected to the liquid inlet end of the liquid inlet pipe (2), and the buffer tank (4) is provided with a foam overflow port (41) for discharging foam, a cleaning liquid inlet (42) for introducing cleaning liquid and a liquid level detector (43) for detecting the internal liquid level; and a liquid outlet of the buffer tank (4) is provided with a valve which can be opened or closed according to a signal of the liquid level detection meter (43).

2. The duplex filter according to claim 1, characterized in that the first tee (10) is connected to the inside of both filters (1) by a first nozzle (101) and a second nozzle (102), respectively, the first nozzle (101) and the second nozzle (102) being directed towards an acute angle of incidence with the inner wall of the filters (1).

3. The duplex filter according to claim 2, wherein a liquid inlet valve (21) is arranged at the liquid inlet pipe (2), and a back-blowing opening for blowing away the dregs by using compressed air is arranged below the liquid inlet valve (21).

4. The duplex filter according to claim 1, wherein a sight glass (32) and a sampling port (33) are arranged at the liquid outlet pipe (3), and a sampling valve is arranged at the sampling port (33).

5. The duplex filter according to any one of claims 1-4, wherein a pipeline filter (34) is arranged at the liquid outlet pipe (3), a discharge port for discharging medicine residue is arranged below the pipeline filter, and a hand valve is arranged at the discharge port.

6. The duplex filter according to claim 5, wherein the back end of the pipe filter (34) is provided with an electromagnetic flow meter.

7. The duplex filter according to any of claims 1-4, wherein the spray balls (14) are connected to the cleaning opening (12) by water pipes, the number of circumferentially arranged spray balls (14) being three, and adjacent circumferentially arranged spray balls (14) being rotationally symmetrically arranged with an angle of (120) degrees with respect to the axis of the filter (1).

8. Duplex filter according to any of claims 1-4, characterized in that the screen (13) comprises: the filter screen comprises a filter screen main body (131) and a filter screen frame (132), wherein the filter screen main body (131) is vertically fixed and clamped on the filter screen frame (132) by adopting a hoop.

9. Duplex filter according to any of claims 1-4, characterized in that one side of the filter (1) is provided with an eyepiece.

10. Duplex filter according to any of claims 1-4, characterized in that the top of the filter (1) is provided with a magnetic float level switch.

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