TWI511777B - Detection apparatus and method using membranes - Google Patents

Description

Detection device and method using diaphragm

The present invention relates generally to a detection device and method for using a diaphragm for monitoring the integrity of a filter diaphragm and the presence of dirt in a fluid, and more particularly, but not exclusively, for detection with integrated cleaning functionality. Apparatus and method.

The use of detection devices or detection methods in filter membrane systems that use one or more membranes to filter fluids is generally known. One such detection device and method is set forth by the Applicant in the PCT Publication No. WO 2007/129994, the disclosure of which is incorporated herein by reference. In such a device and method, the effluent from the filtration membrane is directed through a first permeable membrane and subsequently through a second permeable membrane. As used herein, the term "filter membrane" means one or more membrane filters of a filter membrane system upstream of the detection device, and the term "permeable membrane" means one or more membranes of the detection device. a first pressure P ₁ at the feed side of the first permeable membrane, a second pressure P ₂ between the first and second permeable membranes, and a second permeable membrane as the effluent passes through the permeable membrane The third pressure P ₃ at the permeate side is measured. Subsequently, the equation Π = (P _{1 -} P ₂ ) / (P _{2 -} P ₃ ) is used to determine a ratio 称为 called relative transmembrane pressure (TMP), which is used to determine the integrity of the filter membrane, Or the presence of dirt in the fluid. In the described embodiment, this is done by determining if the time derivative d Π / dt of the ratio Π or ratio is above a corresponding threshold.

While the above detection apparatus and methods provide a relatively simple and inexpensive way of monitoring the integrity of the filter membrane, or the presence of fouling in the fluid, the drawback of reduced life of the permeable membrane has been observed.

The invention is defined in the separate item of the scope of the appended claims. Some optional features of the invention are defined in the appended claims.

In a particular expression, the invention relates to a detection device comprising: a first permeable membrane, and a second permeable membrane; an intermediate section positioned between the first permeable membrane and the second permeable membrane And, at least two pressure sensors configured to generate a signal for determining a ratio between (P ₁ -P ₂ ) and (P ₂ -P ₃ ), and P ₁ is adjacent to the first Permeating the pressure on the outer surface of the membrane, P ₂ is the pressure between the first and second permeable membranes, and P ₃ is the pressure adjacent to the outer surface of the second permeable membrane; the device is configured to: In one mode of operation, fluid is allowed to permeate from the outer surface of the first permeable membrane to the intermediate section and to the second permeable membrane; and, in the second mode of operation, allows fluid to penetrate from the intermediate section to the first A permeable outer surface of the membrane.

Preferably, such a device is further configured to allow at least some of the fluid received on the outer surface of the second permeable membrane to penetrate through the permeable membrane and flow between the permeable membranes, And outside the first permeable membrane.

Preferably, such apparatus further includes at least one inlet and at least one outlet configured to reverse flow between the permeable membranes for switching between the first mode of operation and the second mode of operation. Preferably, the at least one inlet comprises a first inlet and a second inlet, and wherein the at least one outlet comprises a first outlet and a second outlet.

Preferably, the first permeable membrane is configured to allow fluid received at the first inlet to flow over the first permeable membrane to the first outlet and allow some of the fluid to permeate through the first and second Permeating the membrane and flowing out of the second outlet; and wherein the second permeable membrane is configured to allow fluid received at the second inlet to flow over the second permeable membrane to the second outlet, and wherein Some of the fluid permeates through the second and first permeable membranes and flows out of the first outlet.

Preferably, the first permeable membrane is disposed in a plane substantially parallel to a path between the first inlet and the first outlet, and the second permeable membrane is disposed substantially parallel to the one The plane of the path between the second inlet and the second outlet.

Preferably, the apparatus further includes a pressure controller disposed upstream of the first and second permeable membranes; the pressure controller configured to perform execution from the group consisting of the following One or more: reducing the pressure of the fluid to be delivered to the first and second permeable membranes, and easing the pressure of the fluid to be delivered to the first and second permeable membranes.

Preferably, the apparatus further includes a control valve disposed upstream of the first and second permeable membranes and downstream of the pressure controller; the control valve being controllable to direct fluid to the first and the first One of the two permeable membranes. Preferably, the control valve is a three-way control valve having a first open position configured to direct fluid to the first inlet, a second open position configured to direct fluid to the second inlet, and The configuration is a closed position that prevents fluid from reaching the first and second inlets.

Preferably, the apparatus further includes a regulating valve disposed downstream of each of the first and second permeable membranes; each regulating valve configured to regulate a fluid external to the respective permeable membrane pressure.

Preferably, the intermediate section includes an inlet configured to receive fluid directly from the source. Preferably, the device in this form further comprises an outlet valve disposed downstream of the second permeable membrane; the outlet valve being configured to force fluid from the inlet of the intermediate section to flow to the first when closed Permeable outside the diaphragm. Preferably, such a device further includes a pump configured to tap the fluid from the source to the inlet of the intermediate section.

Preferably, the first permeable membrane and the second permeable membrane are each supported by a perforated plate. Preferably, the multiwell plate has an average pore size of at least 45 μm, and preferably about 100 μm.

Preferably, such a device further comprises a venting tube configured to vent air trapped between the first and second permeable membranes.

Preferably, such a device further comprises a plurality of parallel vanes disposed on or adjacent to the outer surfaces of the first and second permeable membranes.

Preferably, the at least two pressure sensors comprise a first pressure sensor, a second pressure sensor, and a third pressure sensor, wherein the first and third pressure sensors are respectively configured A signal is generated that produces a pressure between the first inlet and the first outlet and a pressure between the second inlet and the second outlet.

Preferably, the at least two pressure sensors comprise a first differential pressure gauge and a second differential pressure gauge, wherein the first differential pressure gauge is configured to measure a pressure difference of (P ₁ -P ₂ ), and wherein The second differential pressure gauge is configured to measure the pressure difference (P ₂ -P ₃ ).

In another specific expression, the invention relates to a method of detecting, using a first permeable membrane, a second permeable membrane, and an intermediate section between the first permeable membrane and the second permeable membrane, And each permeable section has an outer surface; the method comprising: flowing fluid from the outer surface of the first permeable membrane to the intermediate section and to the second permeable membrane; determining (P ₁ -P ₂ And a ratio between (P ₂ -P ₃ ), and P ₁ is a pressure adjacent to an outer surface of the first permeable membrane, P ₂ is a pressure between the first and second permeable membranes, and, P ₃ is a pressure adjacent to an outer surface of the second permeable membrane; and flowing fluid from the intermediate section to an outer surface of the first permeable membrane.

Preferably, the method further comprises: flowing a fluid over the outer surface of the second permeable membrane and allowing at least some of the fluid to permeate through the second permeable membrane and flow between the permeable membranes, and To the outside of the first permeable membrane.

Preferably, the method further comprises: reversing the flow of fluid between the permeable membranes.

Preferably, the method further comprises: receiving fluid at the first inlet and flowing the fluid over the first permeable membrane to the first outlet, and at least some of the fluid permeating through the first and second permeable membranes, And flowing out of the second outlet; and receiving fluid at the second inlet and flowing the fluid over the second permeable membrane to the second outlet, and at least some of the fluid permeating through the second and first permeable membrane And flow outside the first exit.

Preferably, the step of reversing the flow comprises controllably directing the fluid to the first permeable membrane or the second permeable membrane.

Preferably, the method further comprises reducing or damaging the pressure of the fluid being directed to the first permeable membrane or the second permeable membrane.

Preferably, the method further comprises: adjusting the fluid pressure outside the first permeable membrane or the second permeable membrane.

Preferably, the method further comprises discharging air trapped between the first and second permeable membranes.

Preferably, the step of flowing fluid from the intermediate section to the outer surface of the first permeable membrane comprises: pumping fluid from the source to the inlet in the intermediate section. Preferably, the method in this form further comprises: restricting fluid flow outside the second permeable membrane to force a majority of the fluid flowing into the intermediate section via the inlet to flow out of the first permeable membrane.

In yet another particular expression, the invention relates to a treatment system comprising the above apparatus in fluid communication with an upstream filtration membrane system, wherein received on a first or second permeable membrane of the apparatus The fluid is the effluent of the upstream filtration membrane system.

Preferably, such a system further comprises a control unit configured to: receive a signal from a pressure sensor of the device; determine a ratio between (P ₁ -P ₂ ) and (P ₂ -P ₃ ) And correlating the ratio with one selected from the group consisting of: failure of the upstream filtration membrane system, and presence of fouling in the effluent.

Preferably, the control unit is further configured to alternately direct the fluid to the first based on a predetermined interval, or a preset value of a ratio between (P ₁ -P ₂ ) and (P ₂ -P ₃ ) One and second permeable membranes.

Preferably, the control unit is further configured to control the collection of fluid from the outlet of the device and to control a pump to draw the collected fluid into the intermediate section via an inlet in the intermediate section. Of course, this fluid need not be the fluid collected, but can be any cleaning fluid.

Reversing the flow between the first permeable membrane, or between the first and second permeable membranes, by using a device, method or system incorporating the features of the claimed patent or the specific expression of the above-described specific expression, is effective The floor allows backwashing and cleaning of the permeable membrane while the detection device or method is in use. In particular, by reversing the flow of fluid through the permeable membrane, dirt that has deposited on the pores or pores of the permeable membrane can be removed. This prevents premature fouling of the permeable membrane and thus extends the useful life of the permeable membrane without the need for downtime to clean the permeable membrane. Similar advantages apply to embodiments of the present invention by providing a central backwash by direct introduction or pumping of fluid into the chamber between the two permeable membranes, rather than providing between the permeable membranes The flow is reversed. This and other advantages obtained by the present invention will be apparent from the following description.

Preferred embodiments of such devices, methods and systems will now be described with reference to the drawings.

Referring to FIG. 1, the apparatus 100 of the preferred embodiment includes first and second permeable membranes in the form of a first membrane test strip 102 and a second membrane test strip 104. Each membrane test strip 102, 104 selectively allows certain materials to permeate through, but does not allow other materials to pass through. That is, each of the membrane test pieces 102, 104 is porous and allows permeate to pass through.

The diaphragm test strips 102, 104 are selected such that a given fouling will cause fouling of the diaphragm test piece when fed to the diaphragm test strip. The fouling is a process that results in a decrease in the performance of the diaphragm test piece, which is caused by the deposition of suspended solids on the outer or outer surface, on the membrane pores of the membrane test piece, or in the membrane pores of the membrane test piece. A typical soil is a particle having a size larger than the pore size of the separator test piece. Other types of potential soils will be known to those skilled in the art and may include other materials that are adsorbed on the surface of the membrane due to their chemical or physical properties, including but not limited to biofoulants.

Each of the first and second diaphragm test strips 102, 104 has an outer surface 102a, 104a and inner surfaces 102b, 104b and is configured to permit receipt on an outer surface of one of the diaphragm test strips At least some of the fluid permeates through the one of the membrane test pieces, flows between the membrane test pieces, and penetrates the other of the membrane test pieces. Details of the preferred form configuration will be described later with reference to Figures 2A and 2B.

Providing at least one inlet and at least one outlet allows the flow between the membrane test pieces 102, 104 to be reversible. In the illustrated embodiment, the first diaphragm test strip 102 is configured to allow fluid received at the first inlet 106 to flow over the outer surface 102a of the first membrane test strip 102 to the first outlet 108, and to allow some of them The fluid permeates through the first diaphragm test piece 102 and the second diaphragm test piece 104 to flow out of the second outlet 110. Similarly, the second diaphragm test strip 104 is configured to allow fluid received at the second inlet 112 to flow over the outer surface 104a of the second membrane test strip 104 to the second outlet 110 and allow some of the fluid to permeate through The second diaphragm test piece 104 and the first diaphragm test piece 102 flow to the outside of the first outlet 108.

In this embodiment, apparatus 100 also includes first, second, and third pressure sensors A, B, and C that are configured to be generated for determining (P ₁ -P ₂ ) and (P ₂ - a pressure signal of a ratio between P ₃ ); P ₁ is a pressure adjacent to the outer surface 102a of the first diaphragm test piece 102 (ie, a pressure between the first inlet 106 and the first outlet 108), P ₂ is The pressure between the diaphragm test piece 102 and the second diaphragm test piece 104, and P ₃ is the pressure adjacent to the outer surface 104a of the second diaphragm test piece 104 (ie, between the second inlet 112 and the second outlet 110) pressure). The operation of the sensors A, B, and C will be described later in this specification.

In this embodiment, the apparatus 100 also includes pressure control in the form of a pressure relief valve located upstream of the diaphragm test strips 102, 104 and connected to the first inlet 106 and the second inlet 112 by tubing or the like. 114. As will be described below, the pressure controller 114 is configured to reduce and/or moderate the pressure of the fluid to be delivered to the diaphragm coupons 102, 104.

The apparatus 100 also includes a control valve in the form of a three-way valve 116 disposed upstream of the first and second diaphragm test strips 102, 104 and downstream of the pressure controller 114. In a preferred form, the three-way valve 116 is located between the pressure controller 114 and the first and second inlets 106, 112. The three-way valve 116 has two open positions and one closed position. In the first open position, fluid is directed to the first inlet 106 (ie, to the first diaphragm test strip 102), and no fluid is directed to the second inlet 112; and in the second open position, the fluid is directed To the second inlet 112 (ie, to the second diaphragm test piece 104), and no fluid is directed to the first inlet 106. In the closed position, the three-way valve 116 is configured to prevent fluid flow to the first and second diaphragm test strips 102, 104.

Additional valves in the form of regulating valves 118 and 120, disposed downstream of each of the first and second diaphragm test strips 102, 104, or downstream of the first outlet 108 and the second outlet 110 or the like On the pipe to regulate fluid pressure and/or fluid flow outside the individual diaphragm test strips or outlets.

The perforated plates 122 and 124 are disposed to support the first and second diaphragm test pieces 102, 104 while allowing fluid to permeate through the surfaces of the diaphragm test pieces 102, 104. The perforated plates 122, 124 each have an average pore size that is larger than the pores of their membrane test pieces without limiting the flow through the membrane test piece. In a preferred form, the porous plates 122, 124 are porous steel sheets having an average pore size of at least 45 μm, and more preferably about 100 μm.

Device 100 also includes a plurality of parallel vanes 126, 128 disposed on or adjacent to outer surfaces 102a, 104a of first and second diaphragm test strips 102, 104. In a preferred form, the plurality of parallel blades 126, 128 are disposed between the first inlet 106 and the first outlet 108 and between the second inlet 112 and the second outlet 110. The vanes 126, 128 are configured to direct or direct fluid received on the outer surface of the diaphragm test strip to its outlet or, more generally, to direct fluid from the inlet to its corresponding outlet. The vanes 126, 128 are also used to provide support for the respective diaphragm test strips 102, 104 during a countercurrent cycle. A venting tube 130 having two exhaust passages 130a and 130b is also provided to vent air trapped between the first and second diaphragm test strips 102, 104, which may otherwise interfere with the first and second diaphragm test strips Fluid flow between or across 102, 104.

The operation of the above preferred form of apparatus will now be described with reference to Figures 2A and 2B. In Figure 2A, the display fluid (generally indicated by arrow F) is entering the device. Specifically, the feed from the source is directed through an upstream pressure controller 114, the incoming pressurized fluid to the flat (or, as it will be described later, the pressure P _1), and / or eliminating excess upstream pressure.

Once passed through the pressure controller 114, the fluid is directed to the first inlet 106 by a three-way control valve 116 set in the first open position. The first mode of operation is provided as follows: fluid at the first inlet 106 flows over the first diaphragm test strip 102 and is directed by a plurality of parallel vanes 126 to the first outlet 108. Some of the fluid (indicated by the dashed arrows) penetrates through the first diaphragm test strip 102 and the porous steel sheet 122 into the intermediate section 200. In the preferred embodiment, the intermediate section 200 is substantially intermediate the distance between the diaphragm coupons 102, 104, but this is not critical as it may alternatively be implemented as between the diaphragm coupons 102, 104. The asymmetric configuration of the intermediate section 200. Path from the perforated plates 122, 124 toward the middle section 200 as a sharpened shape, so as to support the perforated plate 122 and secured in place, while allowing effective pressure P ₂ of the capture, and simultaneously, a test strip membrane The maximum permeable surface area at 102, 104. The air trapped in the intermediate section 200, which may impede fluid permeation, is discharged through the deflation tube 130. All of the fluid in the intermediate section 200 is then infiltrated through the porous steel sheet 124 and the second membrane test piece 104 to flow out of the second outlet 110. It will be appreciated that the dashed arrows have been illustrated as penetrating through the middle of the membrane test strips 102, 104 for clarity only and are therefore not limiting. The actual fluid permeation occurs on the entire surface of the individual diaphragm test pieces.

During the above operation, the pressure readings are taken by the first, second and third pressure sensors A, B and C in the position shown in FIG. A sensor to obtain readings P _1, P reading sensor ₂ made of B and C to obtain sensor readings ₃ of P. The pressure sensor readings are then processed to determine the ratio Π across the diaphragm pressures. As will be appreciated from the PCT Publication No. WO 2007/129994, the ratio Π is determined by calculating (P ₁ -P ₂ )/(P ₂ -P ₃ ). This calculation can be performed by a data processing unit or similar control unit that can determine the ratio 相应 corresponding to receiving a pressure reading or at any given time. The ratio at time t is:

Π(t)=[(P ₁ (t)-P ₂ (t)]/[P ₂ (t)-P ₃ (t)]

Those skilled in the art will appreciate that [(P ₁ (t)-P ₂ (t)] is the diaphragm pressure of the first diaphragm test piece 102, and [P ₂ (t)-P ₃ (t)] is The pressure across the diaphragm of the second diaphragm test piece 104 is such that the enthalpy becomes the ratio of the two diaphragm pressures. As disclosed in the applicant's earlier PCT publication, the ratio Π can vary over time and can be received with the device. The presence of dirt in the fluid, and thus the failure of the upstream filter membrane.

At some point, the three-way control valve 116 is moved to the second open position based on a preset interval, a preset threshold, or a user command to achieve the second mode of operation illustrated in Figure 2B. Here, fluid from the upstream source is directed by the three-way control valve 116 to the second inlet 112, flowing over the second diaphragm test piece 104, and directed by a plurality of parallel vanes 128 to the second outlet 110. Some of the fluid (indicated by the dashed arrow) penetrates through the second membrane test piece 104 and the porous steel sheet 124 into the intermediate section 200. As with the first mode of operation, the air trapped in the intermediate section 200 is discharged through the deflation tube 130. All of the permeate fluid in the intermediate section 200 is subsequently infiltrated through the porous steel sheet 122 and the first membrane test piece 102 to flow out of the first outlet 108. At the same time, the roles of pressure sensors A and C are reversed - sensor A is used to determine the value of P ₃ , and sensor C is used to determine the value of P ₁ . Pressure readings are taken continuously and processed to determine enthalpy.

One difference between the first mode of operation and the second mode of operation is that in the first mode, the flow between the diaphragm test strips 102, 104 (ie, the flow in the intermediate section) is substantially in the second mode The reversal of the flow (ie, the flow in substantially the opposite direction). This allows backwashing or cleaning of the diaphragm test piece with fluid permeation. That is, in the second mode of operation of FIG. 2B, the first diaphragm test piece 102 is cleaned by means of a flow outside the first diaphragm test piece 102, and thus, after the operation of FIG. 2A, the removal is intercepted by the first diaphragm test. Any dirt on or in the holes of the sheet 102. Similarly, if the first mode of operation is repeated after the second mode of operation as shown in FIG. 2A, the second diaphragm test piece 104 will be cleaned by means of the flow outside the second diaphragm test piece 104, and thus, in FIG. 2B After the operation, any dirt trapped on the holes or holes in the second diaphragm test piece 104 is removed. In a preferred form, at any one time, only one of the above modes of operation is implemented and the diaphragm test piece is cleaned by alternating between the first and second modes of operation.

As can be seen from FIGS. 2A and 2B, the first diaphragm test piece 102 is disposed on a plane substantially parallel to the path between the first inlet 106 and the first outlet 108, and the second diaphragm test piece 104 is disposed in a substantial form. The upper surface is parallel to the plane of the path between the second inlet 112 and the second outlet 110. The fluid that is allowed to enter thus flows over the diaphragm coupons 102, 104 (i.e., flows horizontally rather than vertically or forced through), thus providing improved cross-flow on the diaphragm coupons 102, 104, and The life of the diaphragm test pieces 102, 104 is extended. In a preferred form, the planes of the membrane test strips 102, 104 are substantially parallel to each other.

Although the detecting device 100 (and thus the associated diaphragm test strips 102, 104) of Figures 1 and 2A and 2B is shown as being operated in a horizontal position, it is preferred to vertically position the device 100 such that the diaphragm The test strips 102, 104 are in a vertical position (or the diaphragm test strips 102, 104 themselves are positioned vertically). This is advantageous because the effect of gravity is eliminated, so that both of the diaphragm test pieces 102, 104 can be uniformly fouled. In the horizontal position, it has been found that the first diaphragm test piece 102 is fouled faster than the second diaphragm test piece 104. This is due to the gravitational influence of the horizontal positioning of the device 100.

Referring now to Figure 3, the method of the preferred embodiment of the present invention begins at step 300 by flowing a fluid over the outer surface of one of the permeable membranes and allowing some of the fluid to permeate through the permeable membranes. One of these, and flows between the permeable membranes and flows out of the other of the permeable membranes. For clarity, the following description assumes that step 300 encompasses the previously described first mode of operation in which fluid flows over the first diaphragm test strip. This operation will occur when the three-way control valve is in the first open position illustrated in Figure 2A.

At step 302, a ratio across the diaphragm pressure (ie, a ratio between (P ₁ -P ₂ ) and (P ₂ -P ₃ ) is determined; P ₁ is the pressure between the first inlet and the first outlet, P ₂ is the pressure between the first and second permeable membranes, and P ₃ is the pressure between the second inlet and the second outlet). Those skilled in the art will appreciate that the value of the ratio can be determined continuously (assuming continuous pressure measurements) or can be determined at intervals. The value or the value of the ratio thus determined may be used in the relevant process described in the applicant's earlier PCT publication, or may be stored for later processing. Those skilled in the art will also appreciate that differential pressure sensors can be used to measure the pressure across each of the permeable membranes 102 and 104.

At some point, based on the preset interval, the preset threshold, or the user's command, the method continues to step 304 where the flow of fluid between the permeable membranes is reversed. In a preferred form as described earlier, this step occurs in the second mode of operation, which occurs when the three-way control valve is moved to the second open position. This achieves a flow between the permeable membranes as illustrated in Figure 2B, which is substantially in the opposite direction to the flow between the permeable membranes as illustrated in Figure 2A. As described earlier, at least some of the fluid permeates through the second permeable membrane and the first permeable membrane to flow to the first outlet as fluid flows from the second inlet to the second permeable membrane to the second outlet Outside. The effect of the flow of this step is that the fluid penetrating the second diaphragm test piece and the first diaphragm test piece can remove any dirt from the first diaphragm test piece during the backwashing action and effectively clean the first diaphragm test piece.

Once the flow is reversed, the method returns to step 302 to determine the transmembrane pressure ratio, which is based on the reversal of the roles of sensors A and C as described earlier. Monitoring of the integrity of the upstream filter membrane is thus continued while the first permeable membrane is in the backwashing process.

At some point later, based on the preset interval, the preset threshold, or the user's command, the flow of fluid between the permeable membranes is again reversed in step 304. At this point, the second permeable membrane is backwashed while the device monitors the integrity of the upstream filter membrane. It will be appreciated that the above operation allows the device to monitor the integrity of the upstream filter membrane while a permeable membrane is being backwashed.

A processing system embodying the above apparatus and method is illustrated in FIG. Device 100 is shown in fluid communication with a catheter 500 (or more generally, a filtration membrane system) having a filtration membrane 502 upstream of device 100. It is apparent from the graphical content that the fluid received at the first inlet or the second inlet of the device 100 (or on the outer surfaces of the first and second membrane test strips) is the effluent of the filtration membrane 502. The system also includes a control unit 504 configured to receive pressure signals from the first, second, and third pressure sensors (shown as solid circles in the figure) to determine a ratio Π and to select the ratio One of the groups consisting of: failure of the filter membrane 502, and the presence of fouling in the effluent. Control unit 504 is also shown in communication with pressure controller 114, three-way control valve 116, and regulating valves 118 and 120 to control the various components. This allows the control unit 504 to preset a ratio based on the ratio between (P ₁ -P ₂ ) and (P ₂ -P ₃ ), in particular based on a preset interval (eg, every 2 hours) (ie, in the Π When the measured value is above the threshold, control unit 504 causes flow reversal between the permeable membranes, or alternately directs fluid to first permeable membrane and second permeable membrane of device 100 based on user commands. . The control unit 504 has also been configured to be the operating pressure P ₁ of the same value is maintained at a preset value, at preset intervals / time, or the user command to exhaust air, and a controller 114 of the set pressure.

It will be appreciated from the applicant's earlier PCT publication that when the effluent from the upstream filtration membrane 502 is substantially free of fouling, the fluid flowing into the apparatus 100 will also be substantially free of fouling. In this state, the value of the ratio Π will remain relatively constant, and its time derivative will be zero or close to zero. However, when the effluent (and thus the flow into the device 100) contains a significant amount of fouling, one of the first and second membrane test pieces (depending on the position of the three-way control valve 116) will begin to foul. In particular, when the upstream filter membrane 502 fails, dirt in the influent can pass through the filter membrane 502 and subsequently feed to the respective membrane test piece. The substantial amount of dirt being fed to the respective diaphragm test piece will result in fouling of the diaphragm test piece, which in turn causes an increase in flaws. The rate of change of enthalpy will also increase because slow fouling may exist when the upstream filter membrane 502 has not failed, but after the failure, the fouling rate will become significantly faster, resulting in a higher enthalpy Change the rate. Thus, the ratio Π or its time derivative d Π / dt may be associated with the presence of fouling and/or failure of the upstream filter membrane 502. In this system, the preferred embodiment of the present invention operates to reverse the flow between the diaphragm coupons of device 100 to allow the diaphragm test strip to be cleaned while the apparatus continues to operate as described above. This eliminates the need to disconnect or remove the device from the system to clean the diaphragm test piece or to change the diaphragm test piece.

Example results obtainable using the apparatus of the present invention will now be described with reference to Figures 5A and 5B, which are graphs showing test results for sensitivity of the apparatus. These graphs specifically demonstrate the ability of the device to restore the value of the ratio Π by reversing the direction of flow between the diaphragm coupons after fouling.

At point A of Figure 5A, the device is in the first mode of operation under normal operating conditions and the value of Π is set to approximately one. The normal value of Π is set by controlling one or both of the following: (i) using a pressure controller and/or a regulating valve downstream of the first outlet to control the value of P ₁ , or (ii) The value of P ₃ is controlled such that the value of (P ₁ -P ₂ )/(P ₂ -P ₃ ) is substantially 1 using a regulating valve downstream of the second outlet.

Subsequently, at point B1, the simulation was performed by dosing a bentonite solution into the fluid being delivered to the device. This simulates the presence of dirt in the effluent of the filter membrane.

As can be seen from the curve point B2, the value of Π increases from 1 to 3 in about 29 minutes. In practical applications, this increase in threshold, or the rate of change of its value, will be sensed by the control unit and compared to the threshold. Assuming a threshold value of Π, the added value of 3 will clearly indicate the fouling of the first diaphragm test piece and the resulting upstream filter diaphragm failure.

Between points C1 and C2, the ingredients of the bentonite are stopped and the scale diaphragm test piece is replaced for reversing the repeated ingredients in the cycle/direction.

Between C2 and D1, the device is in normal operating conditions in the second mode, and the value of Π is adjusted to approximately one.

At point D1, the ingredients of the bentonite solution are repeated to operate the apparatus in the second mode. From point D2 of the graph, it is apparent that repeated dosing in the reverse cycle results in a Π value increasing from 1 to 3 in about 28 minutes, similar to the result of the compounding in the normal cycle between points B1 and B2.

At point E1, the batching is continued while the flow between the diaphragm coupons is reversed (i.e., returned to the first mode of operation). The bentonite which has previously been fouled by the second diaphragm test piece is washed away and cleaned by approximating the backwashing process. The effect of this backwashing is clearly indicated by the Π value falling from 3 or more in a relatively short time frame to 1 at approximately point E2 (representing recovery of normal operating conditions). The beneficial effect of backwashing can also be seen from Figure 5B, which shows the enthalpy measured as the bentonite formulation begins at point F1 and subsequently reverses the flow at point F2 after 20 minutes. The figure shows that the value of Π increases from 1 to 2, and after the flow reversal at point F2, it drops back to about 1. Subsequently, another 27 minutes is spent before the value of Π increases to 3 at point F3. This demonstrates that when flow reversal occurs in the middle of fouling, fouling is detected in one hour (47 minutes in this case).

Figures 6A and 6B show two alternative embodiments of the apparatus of the present invention. For the sake of clarity, the pressure sensor has been omitted. Referring first to Figure 6A, the configuration of the detection device is similar to the previously described layout, with the addition of a pump 600 and a fluid source 602 in fluid communication with the inlet 604 in the intermediate section 200. In a preferred form, fluid source 602 is configured to store fluid flowing out of one or more of the outlets described earlier. However, it is not necessary, but preferred, it will be appreciated that the fluid can also be a cleaning fluid from any external source. The regulating valves 118, 120 downstream of the outlets may remain open to allow fluid from the intermediate section to exit both of the diaphragm coupons 102, 104, or may be configured to restrict flow out of one of the outlets to Backwashing of one of the diaphragm coupons 102, 104 is optimized. That is, if the first diaphragm test piece 102 should be backwashed, the regulating valve 120 is closed. In this manner, the fluid being drawn into the intermediate section 200 via the inlet 604 will be forced to flow out of the first diaphragm test strip 102 (ie, from the intermediate section 200 to the first diaphragm test strip 102). The surface), and thus any dirt trapped on the holes or holes in the first membrane test strip 102 can be removed. Conversely, if the second diaphragm test piece 104 should be backwashed, the regulator valve 118 is closed. Thus, the fluid being drawn into the intermediate section 200 via the inlet 604 will be forced to flow out of the second membrane test piece 104 (ie, from the intermediate section 200 to the outer surface of the second membrane test piece 104) And thus any dirt trapped on the holes or holes in the second membrane test piece 104 can be removed. As before, in the first mode of operation, fluid is received on the outer surface of one of the diaphragm coupons 102, 104 and directed to the respective outlets such that at least some of the fluid flows to the intermediate section 200. In the second mode of operation, pump 600 is turned on to draw fluid directly into intermediate section 200 during a backwashing motion, flowing to one or both of diaphragm test strips 102, 104. It will be appreciated that where both membrane test strips 102, 104 are backwashed simultaneously (i.e., with the regulator valves 118, 120 open), the fluid from the intermediate section 200 will select a less fouling membrane ( Exit due to lower resistance). This will result in one diaphragm being cleaner than the other.

The above alternative embodiment allows backwashing from the intermediate section 200 at the center, rather than having to rely on flow reversal between the diaphragm coupons 102 and 104. The two-way detection device described earlier in this specification is therefore not critical to the implementation of the central backwashing process. That is, the center backwash can also be applied to the one-way detection device disclosed in the applicant's earlier PCT publication. A schematic diagram of this is provided in Figure 6B. Arrow F shows the one-way flow of fluid through the device in the first mode of operation. As described above, the detecting device includes at least two sensors (not shown) for determining the flaw, the middle between the first and second diaphragm test strips 102, 104, and the diaphragm test strips 102, 104. Section 200, and an inlet 604 in intermediate section 200 for receiving fluid drawn by pump 600 from source 602. An outlet valve (not shown) downstream of the second diaphragm test piece 104 is also provided. This configuration provides a second mode of operation for the device whereby the outlet valve is closed and the pump is operated to draw fluid from the source 602 via the inlet 604 into the intermediate section 200. Due to the closing of the outlet valve, the fluid cannot flow in the usual direction F as previously described and is thus forced to pass through the first permeable membrane 102 during the backwashing action.

In view of the above alternative backwashing embodiments, a central cleaning system can be implemented whereby backwash cleaning can be achieved for multiple detection devices at a time, or once for a single device.

In the flow chart of Figure 7, the method of the above embodiment is shown. In the first mode of operation, fluid flows from the outer surface of the first diaphragm test piece to the intermediate section and beyond the second permeable membrane, which is shown as step 700. Step 702 represents the determination of the threshold as previously described. When center backwashing should be performed, a second mode of operation is performed in step 704 whereby fluid flows from the intermediate section to the outer surface of the first permeable membrane (ie, the reversal of the first mode of operation). As described above, this is accomplished by pumping the fluid directly (i.e., without passing through the septum test piece) into the intermediate section via the inlet in the intermediate section. The fluid being drawn into the intermediate section preferably, but not necessarily, comes from the fluid exiting the second membrane test strip.

Example results of a central backwashing embodiment are shown in the graph of FIG. Line 1 of the graph represents the enthalpy value, while lines 2, 3, and 4 represent the pressures P ₁ , P _{2 ,} and P _{3 , respectively} . During a time period G1, the detecting device operates in the first and second modes of operation of the earlier embodiment, wherein fluid is directed from the outer surface of the first diaphragm test strip to the intermediate section and to the second diaphragm In addition to the test strip, the flow between the membrane strips is reversed by directing the fluid from the second membrane test strip to the intermediate section and beyond the first membrane test strip (ie, the septum test strips) Forward/reverse/forward/reverse flow between). This section can be observed from the wavy shape of the graph during the time period G1. At the period G2, at 0.65 bar, center backwashing was performed. Backwashing is performed simultaneously on the first and second membrane test pieces. After the central backwashing process, a visible drop in the enthalpy is seen in time period G3. Also after backwashing, during time period G3, the device again operates in a forward/reverse/forward/reverse manner similar to G1. It should be noted that the baseline during G3 is shifted to an average of about 1.8 to about 0.5. The upper point of the wave line is for a diaphragm test piece, and the lower part of the wave line is for the second diaphragm test piece.

Those skilled in the art will appreciate the advantages of the present invention from the foregoing description. For example, the apparatus and system of the present invention configured as described above, or by carrying out the method of the present invention, can effectively clean the diaphragm test piece without having to stop the operation of the present invention. In particular, by providing an inlet and an outlet such that the fluid flow between the first and second membrane test strips is reversible, or by providing a central backwash inlet in the intermediate section, the present invention allows for backwashing and thus cleaning Each diaphragm test piece. Therefore, the ratio Π or its time derivative d Π / dt can be monitored once and without interruption for a long period of time. In the case of backwashing by flow reversal, there is also a related benefit: by having a cleaning function integrated with the operation of the present invention, the useful life of the diaphragm test piece is extended. Furthermore, in the case where the diaphragm test pieces are each disposed on a plane parallel to the path between the respective inlet and outlet, most of the fluid entering the device flows through the diaphragm test piece instead of being forced to pass through. In the meantime. It has been found that the fouling rate of the diaphragm test piece is reduced. In the case where a pressure controller is used upstream of the diaphragm test pieces, the feed pressure to the diaphragms can be reduced/flattened, thus eliminating any disturbance of P ₁ based on the unstable feed pressure, which in turn allows the contrast ratio Π or The more consistent determination of the time derivative d Π / dt , regardless of the feed pressure. Similar controls are also provided for P ₁ and P ₃ , wherein the regulating valves are applied downstream of the outlet of the device . This control allows the device to be calibrated to provide a theoretical value of the ratio Π1 under normal operation. The use of parallel vanes on or adjacent to the outer surface of the membrane test pieces facilitates flushing or removal of fouling/suspended solids in the cross-flow on the membrane test pieces. Improvement through the diaphragm test pieces by providing a perforated plate as a support that allows full and efficient use of the entire surface area of the diaphragm test piece and by removing trapped air or bubbles from the intermediate section using a deflation tube The fluid flows between. This can be compared to the applicant's earlier invention of the PCT publication, wherein the membrane test pieces are supported by a plurality of plates having 1 mm holes (which will only allow penetration through such holes), and wherein, Special measures are proposed for the removal of trapped air bubbles.

The foregoing description of the preferred embodiments of the invention may be construed as a For example, it will be appreciated from the above description that it is not critical to have two inlets and two outlets as illustrated in the figure. All that is required is only a configuration that permits the flow through at least the first diaphragm test piece to be reversible while allowing backwashing of at least the first diaphragm test piece. This can be achieved by setting an entry to the middle section of the applicant's earlier one-way detection device (as shown in Figure 6B). For a two-way detection device, for example, by providing an inlet and an outlet, the backwashing of the first diaphragm test piece can be achieved, and the inlet and the outlet each have one or more internal controllable channels, branches, valves or Analogs to direct fluids accordingly. Similarly, it is not critical that the fluid flowing between the septum coupons is obtained directly from the inlet adjacent to the septum test strips. As outlined with reference to Figures 6A and 6B, it is contemplated that the flow from the first outlet and the second outlet may be pooled and the collected solution may be pumped between the two diaphragm coupons via a pump at preset time intervals. The chamber (ie, the intermediate section 200) is configured to achieve a central backwashing process. In this example, control valve 116 will close and regulator valves 118 and 120 will open. The solution drawn into the chamber between the first and second membrane test strips will flow through the first and second membrane test pieces, thereby effectively backwashing the two membrane test pieces. The control unit described earlier can be configured to perform the necessary fluid collection, pumping, and valve control to accomplish this. As mentioned earlier, this central backwashing process can also be applied to the one-way device of the applicant's earlier PCT publication.

It is not critical to provide a porous steel plate to support the diaphragm test piece. Other hard materials (eg, PVC) that are inert to water may be used as necessary or desired. Alternatively, the membrane test pieces may be supported at their periphery or supported by a non-porous plate provided with sufficient holes to allow fluid flow between the test pieces of the membranes. In the case of a perforated plate, the holes need not be limited to an average size of 100 μm, but may instead be as large as 1 mm as long as the holes are configured such that the plate still provides sufficient support for its diaphragm test piece.

It will also be appreciated that the placement of the deflation tube is not critical because, in certain embodiments, the bubbles may instead be allowed to penetrate outside of the septum test strips.

In the case of a pressure sensor, it is not critical to have three pressure sensors or sensors. It is contemplated that two differential pressure gauges can be used that will measure the pressure differential across the first diaphragm test strip and the second diaphragm test strip. In the case of a differential pressure gauge, only two sensors are required instead of three, since each differential pressure gauge has a first conduit for placement on one side of the permeable membrane and for placement in a permeable membrane The second pipe on the other side. Each differential pressure gauge senses the difference across the respective diaphragms and produces a signal indicative of the difference. For the apparatus of the present invention, one differential pressure gauge can be applied to the first permeable membrane and the second differential pressure gauge can be applied to the second permeable membrane. That is, a differential pressure gauge will measure the pressure on the first diaphragm test piece, which will give a value of (P ₁ -P ₂ ), and the second differential pressure gauge will measure the pressure difference on the second diaphragm test piece, The value of (P _{2 -} P ₃ ) will be given. The ratio of the two gauge readings can be used as described above to calculate the value of Π.

In the case of a regulating valve, the calibrated orifice can be used instead if necessary or required.

With respect to the control unit of the system, the described determinations and controls can be implemented in hardware using a computer device, for example, using an individual or separate processor that is programmed to make determinations and controls. The control unit may alternatively be implemented in software as a series of instructions that, when executed by a processor or other computing device, perform the same functions as the embodiments described above. A combination of hardware and software implementations can also be used. Additionally, although the described and exemplified control unit controls only one detection device of the present invention, the control unit can be configured to control a plurality of detection devices (e.g., a network of detection devices). Variations such as these will be covered by the scope of the claimed invention.

100. . . (detection) device

102. . . (first) diaphragm test piece; (first) permeable membrane

102a. . . The outer surface

102b. . . The inner surface

104. . . (second) diaphragm test piece; (second) permeable membrane

104a. . . The outer surface

104b. . . The inner surface

106. . . (first) entrance

108. . . (first) exit

110. . . (second) exit

112. . . (second) entrance

114. . . pressure controller

116. . . Three-way valve; (three-way) control valve

118. . . Regulating valve

120. . . Regulating valve

122. . . Porous plate

124. . . Porous plate

126. . . (parallel) blade

128. . . (parallel) blade

130. . . Venting tube

130a. . . Exhaust passage

130b. . . Exhaust passage

200. . . Intermediate section

500. . . catheter

502. . . Filter diaphragm

504. . . control unit

600. . . Pump

602. . . Fluid source

604. . . Entrance

A. . . (first) (pressure) sensor

B. . . (second) (pressure) sensor

C. . . (third) (pressure) sensor

F. . . (fluid, flow) direction

Figure 1 is a block diagram of this device.

2A and 2B are block diagrams of devices in a first mode of operation and a second mode of operation, respectively.

Figure 3 is a flow chart of this method.

Figure 4 is a block diagram of a system including such a device.

Figures 5A and 5B are graphs of test results for this device.

6A and 6B are block diagrams of alternative embodiments of the apparatus.

Figure 7 is a flow chart of an alternate embodiment of this method.

Figure 8 is a graph showing the test results of the apparatus of Figure 6A.

100. . . (detection) device

102. . . (first) diaphragm test piece; (first) permeable membrane

102a. . . The outer surface

102b. . . The inner surface

104. . . (second) diaphragm test piece; (second) permeable membrane

104a. . . The outer surface

104b. . . The inner surface

106. . . (first) entrance

108. . . (first) exit

110. . . (second) exit

112. . . (second) entrance

114. . . pressure controller

116. . . Three-way valve; (three-way) control valve

118. . . Regulating valve

120. . . Regulating valve

122. . . Porous plate

124. . . Porous plate

126. . . (parallel) blade

128. . . (parallel) blade

130. . . Venting tube

130a. . . Exhaust passage

130b. . . Exhaust passage

Claims (34)

A detecting device comprising: a first permeable membrane, and a second permeable membrane, an intermediate section between the first permeable membrane and the second permeable membrane, and at least two pressure sensors, Configuring to generate a signal for determining the ratio between (P ₁ -P ₂ ) and (P ₂ -P ₃ ); P ₁ is the pressure adjacent to the outer surface of the first permeable membrane, P ₂ is the first the pressure between the diaphragm and the second permeable, and P ₃ is the pressure adjacent to the outside surface of the second permeable membrane; this means is configured to become: in a first mode of operation, allowing fluid from the first permeable membrane The outer surface penetrates into the intermediate section and out of the second permeable membrane; and in the second mode of operation, fluid is allowed to penetrate from the intermediate section to the outer surface of the first permeable membrane. The detecting device of claim 1, wherein the device is further configured to allow at least some of the fluid received on the outer surface of the second permeable membrane to penetrate through the permeable membrane and The permeable membranes flow between the membranes and out of the first permeable membrane. The detecting device of claim 2, wherein the device further comprises at least one inlet and at least one outlet configured to reverse the flow between the permeable membranes for the first mode of operation and Switch between the two operating modes. The detecting device of claim 3, wherein the at least one inlet comprises a first inlet and a second inlet, and wherein the at least one outlet comprises a first outlet and a second outlet. The detecting device of claim 4, wherein the first permeable membrane is configured to allow fluid received at the first inlet to flow to the first outlet on the first permeable membrane and allow some of Fluid permeates through the first and second permeable membranes and flows out of the second outlet; and wherein the second permeable membrane is configured to allow fluid received at the second inlet to be second permeable The diaphragm flows up to the second outlet and allows some of the fluid to permeate through the second and first permeable membranes and out of the first outlet. The detecting device of claim 4, wherein the first permeable membrane is disposed on a plane substantially parallel to a path between the first inlet and the first outlet, and the second The permeable membrane is disposed in a plane substantially parallel to a path between the second inlet and the second outlet. The detecting device of claim 4, further comprising a pressure controller disposed upstream of the first and second permeable membranes; the pressure controller configured to perform execution from the following One or more of the group consisting of: reducing the pressure of the fluid to be delivered to the first and second permeable membranes, and smoothing the pressure of the fluid to be delivered to the first and second permeable membranes. The detecting device of claim 7, further comprising a control valve disposed upstream of the first and second permeable membranes and downstream of the pressure controller; the control valve is controllable to The fluid is directed to one of the first and second permeable membranes. The detecting device of claim 8, wherein the control valve is a three-way control valve having a first open position configured to direct fluid to the first inlet, configured to direct fluid to A second open position of the second inlet and a closed position configured to prevent fluid from reaching the first and second inlets. A detecting device according to any one of the preceding claims, further comprising a regulating valve disposed downstream of each of the first and second permeable membranes; each regulating valve being configured to be adjusted Individual fluid pressures that are permeable to the outside of the diaphragm. The detecting device of claim 1, wherein the intermediate section includes an inlet configured to receive fluid from the source. The detecting device of claim 11, further comprising an outlet valve disposed downstream of the second permeable membrane; the outlet valve being configured to force the inlet from the intermediate section when closed The fluid flows out of the first permeable membrane. The detecting device of claim 12, further comprising a pump configured to be an inlet from the source pumping fluid to the intermediate section. For example, in the detecting device of claim 1, wherein the first The osmotic membrane and the second permeable membrane are each supported by a perforated plate. The detecting device of claim 14, wherein the porous plate has an average pore size of at least 45 μm. The detecting device of claim 15, wherein the porous plate has an average pore size of about 100 μm. The detecting device of claim 1, wherein the venting tube further comprises a venting tube configured to discharge air trapped between the first and second permeable membranes. The detecting device of claim 1, wherein the detecting device further comprises a plurality of parallel blades disposed on or adjacent to the outer surfaces of the first and second permeable membranes. The detecting device of claim 1, wherein the at least two pressure sensors comprise a first pressure sensor, a second pressure sensor, and a third pressure sensor, wherein the first The third pressure sensors are each configured to generate a signal indicative of a pressure between the first inlet and the first outlet and a pressure between the second inlet and the second outlet. The detecting device of claim 1, wherein the at least two pressure sensors comprise a first differential pressure gauge and a second differential pressure gauge, wherein the first differential pressure gauge is configured to measure (P ₁ The pressure difference of -P ₂ ), and wherein the second differential pressure gauge is configured to measure the pressure difference of (P ₂ -P ₃ ). A method of detecting a first permeable membrane, a second permeable membrane, and an intermediate section between the first permeable membrane and the second permeable membrane, each permeable section having an outer surface; The method includes flowing a fluid from an outer surface of the first permeable membrane to an intermediate section and to a second permeable membrane; determining between (P ₁ -P ₂ ) and (P ₂ -P ₃ ) Ratio; P ₁ is the pressure adjacent to the outer surface of the first permeable membrane, P ₂ is the pressure between the first and second permeable membranes, and P ₃ is adjacent to the outer surface of the second permeable membrane Pressure; and flowing fluid from the intermediate section to the outer surface of the first permeable membrane. The detecting method of claim 21, further comprising: flowing a fluid on an outer surface of the second permeable membrane, and allowing at least some of the fluid to permeate through the second permeable membrane, and Flows between the osmotic membranes and out of the first permeable membrane. The method of detecting the scope of claim 22, further comprising: reversing the flow of the fluid between the permeable membranes. The detecting method of claim 23, further comprising: receiving a fluid at the first inlet, and flowing the fluid on the first permeable membrane to the first outlet, and at least some of the fluid permeating through the first And a second permeable membrane and flowing out of the second outlet; and receiving fluid at the second inlet and flowing the fluid over the second permeable membrane to the second outlet, and at least some of the fluid permeating through the second And the first permeable membrane and flowing out of the first outlet. The detecting method of claim 24, wherein the step of reversing the flow comprises: controllably directing the fluid to the first permeable membrane or the second permeable membrane. The detecting method of claim 21, wherein the method further comprises: reducing or grading a pressure of the fluid being guided to the first permeable membrane or the second permeable membrane. The detecting method of claim 21, further comprising: adjusting a fluid pressure outside the first permeable membrane or the second permeable membrane. The detecting method of claim 21, further comprising: discharging air trapped between the first and second permeable membranes. The method of detecting in claim 21, wherein the step of flowing fluid from the intermediate section to the outer surface of the first permeable membrane comprises: pumping fluid from the source to the inlet in the intermediate section. The detecting method of claim 29, further comprising: restricting fluid flow outside the second permeable membrane to force most of the fluid flowing into the intermediate section via the inlet to flow out of the first permeable membrane . A processing system comprising the apparatus of claim 1 in fluid communication with an upstream filtration membrane system, wherein the fluid received on the first or second permeable membrane of the apparatus is the upstream filtration membrane System effluent. The processing system of claim 31, further comprising a control unit configured to: receive a signal from a pressure sensor of the device; determine (P ₁ -P ₂ ) and (P ₂ -P ₃ ) a ratio between; and correlating the ratio with one of the group consisting of: a failure of the upstream filtration membrane system, and the presence of fouling in the effluent. The processing system of claim 32, wherein the control unit is further configured to be based on a preset interval, or a ratio between (P ₁ -P ₂ ) and (P ₂ -P ₃ ) A value is provided to alternately direct fluid to the first and second permeable membranes. The processing system of claim 31, wherein the control unit is further configured to control collection of fluid from an outlet of the device and to control a pump to collect the collected via an inlet in the intermediate section The fluid is pumped into the middle section.