KR20100129379A - Low fouled hollow fiber membrane module and its application of water treatment - Google Patents

Abstract

PURPOSE: A low contamination hollow fiber membrane module and a water-treatment apparatus using thereof are provided to prevent the reduction of the water insertion flow speed and the water quality by the concentration polarization and a solute layer. CONSTITUTION: A low contamination hollow fiber membrane module comprises the following: a hollow fiber membrane(101); a case(102) for maintaining the filtering pressure, and for protecting the hollow fiber membrane; a lower side blocking unit(108) dividing processing water and insertion water; an upper side blocking unit(109) diving the processing water and condensed water; an insertion water nozzle(103) for flowing in the insertion water to the module; and a rotating divider(104) inducing the separation of foreign materials from the waters.

Description

Low Pollution Hollow Fiber Membrane Module and Water Treatment Device Using It {Low Fouled Hollow Fiber Membrane Module and its Application of Water Treatment}

The present invention relates to a low-pollution hollow fiber membrane module modularized to use the hollow fiber membrane for water treatment, and a water treatment device using the same, more specifically, solute using a hollow fiber membrane irrespective of reverse osmosis ultrafiltration Concentration polarization near the surface of the membrane when removing a large number of macromolecules or colloidal substances, or removing particulates, suspended matter, or protozoa or viruses from water. ), The soak layer deposited on the membrane surface and the membrane fouling formed inside the membrane are minimized to minimize the decrease of permeate and the softening of the upper and lower blocking agents at both ends of the low pollution hollow fiber membrane module By preventing stress breakage in the boundary layer of hollow fiber membranes and blockers through Li film life that contamination hollow fiber membrane module to maximize and to a water treatment apparatus using it.

Separation, purification and fractionation using membranes is widely practiced today throughout the industry. Membranes have the advantage of being able to effectively separate solutions or mixtures with low energy and easily achieve the desired purpose by simple operation without generating third waste after separation.

In general, however, when the separation membrane is used to separate particulate matter or solutes, the exclusion particles present in the solution have a very small diffusion rate, so that the back diffusion easily occurs even when the concentration gradient between the center and the surface of the membrane is large. As a result, concentration polarization phenomenon occurs in which the concentration of the solute increases near the surface of the membrane, or these concentration polarization layers progress, and phase transition occurs in the solute continuous phase on the surface of the separation membrane, so that the solute layer is formed. Membrane contamination may occur due to adsorption on the pores and the pores being blocked by particles of similar size to the pores.

Therefore, the permeation rate of the membrane is drastically lowered as the operation time passes by these phenomena. In the case of a loss of economy due to a decrease in the permeate flow rate, the device is usually stopped and cleaned with chemicals. In general, when the recovery rate is less than 60 to 70 percent of the initial permeate flow rate, a new membrane is replaced.

In addition, the hollow fiber membrane is manufactured as a module for converging a large amount of hollow fiber membranes in bundles for application in actual industrial processes. At this time, the hollow fiber membranes are fixed, and at the same time, the mixture of inflow water or concentrated water and treated water is prevented. The blocker is installed directly, and the blocker is in direct contact with the hollow fiber membrane, so if the hollow fiber membrane is used for a long time, it is easily cut due to excessive stress, and the initially cut hollow fiber membrane is used through repair, but when the repair limit value is exceeded, Replace with a membrane.

As a development of a module to compensate for such a disadvantage of the membrane, Korean Patent Application No. 1992-27149 divides the membrane concentrated in the membrane module into several bundles when the membrane is cut, instead of replacing the whole module by a bundle We devised a way to reduce the replacement cost. However, this method has a drawback in that the case occupies a large volume, and also does not fundamentally prevent the cutting due to stress between the blocking agent and the separator.

In addition, Korean Patent Application No. 1995-22265 devised a method for sterilization to reduce membrane fouling caused by membrane blockage, but there is a difficulty that an ozone device or an ultraviolet device for sterilization should be additionally introduced in the process. . Korean Patent Application No. 2001-5622 has devised a method of covering one or both ends of a separator in order to prevent cutting due to stress between the blocking agent and the hollow fiber separator. This method can compensate for the disadvantages of hollow fiber membranes, but it is difficult to accurately implement the coating length, or it is difficult to do manual work for this purpose. Also, the membrane area is reduced because the coating part must be subtracted from the effective membrane area. I have a problem. Korean Patent Application No. 2003-6216 and Korean Patent No. 535301 have invented a low pollution hollow fiber membrane module capable of removing contaminants such as scale generated during water treatment by installing an air hole in the center of the membrane module. However, if the air hole is installed inside the hollow fiber membrane insertion amount is reduced, there is a problem that the filling density is eventually reduced. Korean Patent 547074 has invented a method of using a flexible potting material to prevent the cutting phenomenon due to stress concentration to the separator between the potting material and the separator. However, this type of method has a problem that can not be fixed due to the flexibility of the potting material.

Therefore, in installing the upper and lower blockers of the hollow fiber membrane module in order to shield the inflow of water or concentrated water, the stress concentrating between the blocker and the hollow fiber membrane is removed to reduce the phenomenon that the hollow fiber membrane is cut, the membrane module There is a need for a new low pollution hollow fiber membrane module and a water treatment device using the same method that can be used for a long time without reducing the contamination of the membrane.

Accordingly, an object of the present invention is to solve the above problems, to remove membrane fouling, solute layer formation, concentration polarization phenomenon to extend the life of the membrane and also to minimize the cleaning time of the membrane to maximize the amount of permeate without reducing the rejection rate The present invention provides a highly durable low-contamination hollow fiber membrane module and a water treatment device using the same by preventing the hollow fiber membrane from being cut by gradually softening the upper and lower blocking agents of the hollow fiber membrane module.

According to an aspect of the present invention, the hollow fiber membrane, a case for protecting the hollow fiber membrane and maintaining a filtration pressure, a lower barrier member separating the treated water and the influent, an upper barrier member separating the treated and concentrated water, and the influent water into the membrane module A low pollution hollow fiber membrane module is provided that includes an inflow nozzle into which the inflow water is introduced, a concentrated water nozzle from which the concentrated water is discharged, and a treated water nozzle from which the treated water is discharged. A rotary distribution plate which contacts the hollow fiber membrane while rotating inside and induces foreign substances having different specific gravity from the influent water to be separated by centrifugal force; An inflow water distribution port for implementing an even distribution so that the inflow water does not flow unevenly within the module; A separation particle collecting unit in which the separation particle is integrated through the separation particle moving hole without contacting the hollow fiber membrane of the module; And a separator particle outlet for discharging the collected separator particles out of the system.

The upper and lower barrier members may be polymerized to allow the nitriding to proceed while the inner side of the low-pollution hollow fiber membrane module is advanced from both ends of the low-pollution hollow fiber membrane module to prevent the low-pollution hollow fiber membrane from being cut at the contact portion with the adhesive.

The rotary distribution plate may be installed in a circular shape along the lower case in the lower case of the module to induce the inflow of the rotary flow along the outer surface of the rotary distribution plate and remove some or all of the foreign matter. have.

The separating particle collecting unit may be installed under the low pollution hollow fiber membrane module, and the separating particle moving hole may be installed in the lower blocking member so that the foreign matter is collected.

The rotary distribution plate may have an inflow distribution hole in front of the inflow nozzle, and the inflow distribution may be evenly generated by increasing the size of the inflow distribution hole as the inflow water distribution hole moves away from the inflow nozzle.

According to another aspect of the present invention, the hollow fiber membrane, a case for protecting the hollow fiber membrane and maintaining the filtration pressure, a lower barrier material separating the treated water and the influent, an upper barrier material separating the treated water and the concentrated water, and the inflow water into the membrane module Is provided a water treatment apparatus using a low pollution hollow fiber membrane module including an inlet nozzle, the inlet nozzle in which the concentrated water is discharged, and the treated water nozzle discharged the treated water, the low pollution hollow fiber membrane module is A rotary distribution plate which contacts the hollow fiber membrane while the inflow water rotates inside the module and induces foreign substances having different specific gravity from the inflow water to be separated by centrifugal force; An inflow water distribution port for implementing an even distribution so that the inflow water does not flow unevenly within the module; A separation particle collecting unit in which the separation particle is integrated through the separation particle moving hole without contacting the hollow fiber membrane of the module; And a separate particle outlet for discharging the collected separated particles out of the system, and periodically removes the foreign matter collected in the separated particle collecting part through the separated particle discharge port.

The water treatment may include at least one of purified water treatment, reused water treatment, effluent treatment, effluent reuse treatment, river maintenance water treatment, seawater desalination pretreatment, ship ballast water treatment, and household reuse water treatment.

In the removal of the foreign matter collected in the separated particle outlet can be carried out at least any one of automatic discharge by maintaining a constant time interval, automatic discharge by maintaining a constant membrane filtration pressure rising interval, and automatic discharge immediately after backwash.

Separation membrane module according to the configuration and operation of the present invention solves the decrease in permeation flux and decrease in permeation water quality due to concentration polarization and solute layer, which are not solved in the conventional membrane for water treatment when the hollow fiber membrane module is used for water treatment. By reducing the stress between the and the separator to reduce the cutting phenomenon of the hollow fiber membrane can extend the cleaning cycle and service life of the membrane and can be applied to a wider range of applications.

Hereinafter, the same reference numerals will be described in detail with reference to the accompanying drawings, with reference to the same components preferred embodiments of the present invention. The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary meanings and should be construed in accordance with the technical meanings and concepts of the present invention.

The embodiments described in the specification and the configuration shown in the drawings are preferred embodiments of the present invention, and do not represent all of the technical idea of the present invention, various equivalents and modifications that can be substituted for them at the time of the present application are There may be.

Figure 1 is a schematic diagram showing a low pollution hollow fiber membrane module according to an embodiment of the present invention.

Low pollution hollow fiber membrane module according to an embodiment of the present invention is a hollow fiber membrane (101); A case 102 for protecting the hollow fiber membrane and maintaining filtration pressure; A lower barrier 108 separating the treated water and the influent; An upper barrier 109 separating the treated water and the concentrated water; An inflow water nozzle 103 through which inflow water flows into the membrane module; A concentrated water nozzle 110 through which the concentrated water is discharged; And in addition to the basic hollow fiber membrane module composed of the treated water nozzle 111 through which the treated water is discharged, inflow water flows inside the module to ensure low pollution performance and long-term life by avoiding cutting of the membrane. A rotary distribution plate 104 which is in contact with the hollow fiber membrane 101 and induces separation of water, specific substances such as suspended matter and particulate matter from the influent, by centrifugal force; An inflow water distribution port 112 for implementing an even distribution so that inflow water does not flow unevenly within the module; A separation particle collecting part 105 in which the separation particles are integrated through the separation particle moving hole 106 without contacting the hollow fiber membrane 101 of the module; And a separation particle outlet 107 for discharging the collected separation particles out of the system.

Hollow fiber membrane module is generally divided into pressurized membrane module and submerged membrane module. The pressurized membrane module uses a pump to introduce pressurized influent into the membrane module so that the pressure difference between the raw water side with high pressure and the relatively low treated water side The module is configured to remove contaminants in the raw water.

Since the membrane is divided into hollow fiber membrane, tubular membrane, spiral wound membrane according to the size and shape of the diameter, the pressurized hollow fiber membrane module generally protects the hollow fiber membrane 101 and the hollow fiber membrane, the case 102 to maintain the filtration pressure, A lower barrier member 108 separating the treated water and the influent, an upper barrier member 109 separating the treated water and the concentrated water, an inlet nozzle 103 into which the influent flows into the membrane module, and a concentrated water nozzle 110 through which the concentrated water is discharged ), The treated water nozzle 111 through which the treated water is discharged.

The low pollution hollow fiber membrane module according to an embodiment of the present invention is the basic hollow fiber membrane module, in order to ensure long-term life by avoiding the low pollution performance and the cutting of the membrane, the incoming inflow is rotated inside the module While contacting the hollow fiber membrane 101, while rotating in the distribution plate 104, which induces the separation of suspended solids, particulate matter and other specific gravity in the inflow water by centrifugal force, the inflow is uneven flow in the module Inflow water distribution port 112 to implement an even distribution so as not to be made, the separation particle collecting unit 105, the separation particles are collected through the separation particle moving port 106 without contacting the hollow fiber membrane 101 of the module Separated particle outlet 107 for discharging the separated particles to the outside of the system is further included.

In addition, when the low pollution hollow fiber membrane module is applied to the water treatment apparatus of FIG. 5 to be described later, the contaminants collected in the separate particle collecting part may periodically discharge the raw water to the outside of the system.

Figure 2 is a schematic diagram showing a lower barrier member 108 and the separate particle collecting unit 105 according to an embodiment of the present invention.

Referring to FIG. 2, the lower barrier material 108 is polyurethane, epoxy, silicone, or the like as a polymer adhesive, and forms a hard barrier material at the lower part and gradually softens as it proceeds upward.

The barrier material may be made of the same type of polymer.

The hollow fiber membrane 101 is to penetrate deeply to the hard barrier material to be fixed, and the separation material moving hole 106 is configured to the separation material moving hole is formed to move the particulate matter separated by centrifugal force to the separation particle collecting portion. ), And the particulate matter passing through the separation particle moving port is collected in the separation particle collecting unit 105.

3 is a block diagram schematically showing the lower barrier material 108 and the hollow fiber membrane 101, the separation particle moving port 106, the rotary distribution plate 104 of the low pollution hollow fiber membrane module.

Referring to FIG. 3, the inflow water introduced through the inflow nozzle 103 is separated from foreign substances such as suspended matter or particulate matter in the inflow water by centrifugal force generated as the rotation distribution plate 104 and the case rotate. Allow to settle.

4 is a configuration diagram schematically illustrating the inflow water nozzle 103, the rotation distribution plate 104, and the inflow water distribution port 112.

Referring to FIG. 4, the inlet distributor 112 has an inlet water outlet 112 so that the inlet water can move to the center of the module having the hollow fiber membrane, and the inlet outlet 112 is farther from the inlet nozzle. It is made large so that the inflow of water from the inlet to the central portion of the module to prevent the pulling phenomenon.

Figure 5 is a schematic diagram showing a device for applying a low pollution hollow fiber membrane module according to an embodiment of the present invention to the water treatment is configured to periodically discharge the contaminants collected in the separation particle collecting unit.

The water treatment apparatus of FIG. 5 is transferred to the membrane inflow water collection tank 502 through the raw water inflow pipe 501, and the inflow water is supplied to the low pollution hollow fiber membrane module 506 from the inflow control valve 503. This is controlled, and the crude material is separated through the strainer 504 before the influent is introduced into the low pollution hollow fiber membrane module 506 by the influent feed pump 505 through the membrane influent pipe 519.

Separation particles separated from the low pollution hollow fiber membrane module 506 is periodically discharged out of the system through the separation particle outlet 507, the treated water is transferred to the treated water tank 510 through the treated water discharge pipe 509.

A portion of the treated water stored in the treated water tank 510 is introduced into the treated water discharge pipe 509 by the backwash pump 512 to remove contaminants formed on the outer surface of the separation membrane, and the treated water is then backwashed by the valve 515. Is adjusted by.

The chemicals are mixed with the treated water from the chemical tank 511 at the time of backwashing or chemical cleaning, and these mixed liquids are adjusted by the backwash adjustment valve 514. During backwashing, the concentrated water circulation pipe 517 which circulates to the membrane inflow water collecting tank 502 during filtration is closed and the backwash discharge pipe 518 is opened.

During backwashing or physical cleaning, the compressor 508 operates to introduce air into the low pollution hollow fiber membrane module 506 to maximize the backwashing effect, and the air is regulated by the regulator 513.

After the backwash is finished, the air discharge valve 516 is opened to discharge the air remaining in the module and the contaminants remaining in the backwash water and the separate particle collecting part.

Hereinafter, an embodiment of the low pollution hollow fiber membrane module and the water treatment apparatus using the same according to the present invention will be described in more detail, but the present invention is not limited thereto.

≪ Example 1 >

The low pollution hollow fiber membrane module was installed in the water treatment apparatus of FIG. 5 and coagulated sedimentation of the raw water of the Han River was introduced into the water treatment apparatus after the first pretreatment, and the raw water measurement point, the membrane inflow measurement point, the concentrated water measurement point, and the backwash water of FIG. The suspended particles were measured at the measuring point and the outlet of the separated particle, and the relative ratios were calculated using the concentration of the standard suspended particle at the measuring point as 1, and the results are shown in Table 1.

The permeate flux was 1.5 meters / day and 1.8 meters / day. The low pollution hollow fiber membrane module had an effective membrane area of 75 square meters, the pore size was 50 nanometers, and the hollow fiber membrane was filled with about 8900 strands.

The concentration of suspended particles in the treated water was 0, and the concentration of suspended particles in the concentrated water at the measuring point was 1.1, which was almost similar to the membrane inflow, whereas the concentration of suspended particles was 30 at the measuring point. Increasing the concentration of membrane influent suspended particles by 2 and 3 times higher than the standard suspended particle concentration resulted in greater concentration of contaminants at the separated particle outlet.

Comparative Example 1

A general hollow fiber membrane module was mounted in the water treatment apparatus of FIG. 5 and tested under the same conditions as in Example 1. Membrane influent flows into the bottom of the hollow fiber membrane module and excludes the separation particle outlet. As a result of measuring the concentration of suspended particles in the same manner as in <Example 1>, the concentration of suspended particles on the treated water side was 0, and the concentration ratio of suspended particles in the concentrated water at the measurement point was 1.8, which was very high, circulating the concentrated water through the membrane inflow tank. In this case, a cycle was formed to connect the membrane inflow water tank, the membrane inflow water pipe, the hollow fiber membrane module, and the concentrated water circulation pipe so that contaminants were trapped in the cycle.

<Example 2>

The upper and lower barrier materials of the low-pollution hollow fiber membrane module are made of polyurethane material and the ends of the module are made of hard material without bubble holes.When the hollow fiber membrane is broken after hardening by increasing the air foam as it proceeds inside Shake from side to side until the recovery was measured and compared with the case of a hard blocker, the ratio is shown in Table 3. Left and right wetting ratio was 10 when the air injection ratio was 0 ~ 10%, and it was 25 when the air injection ratio was 0 ~ 20%, and 28 when 0 ~ 30%. However, when the air injection ratio was 0-50%, the blocking role of the hard urethane was limited.

The technical spirit of the present invention has been described above with reference to the accompanying drawings, but this is only illustrative of the preferred embodiments of the present invention and is not intended to limit the present invention. In addition, it is a matter of course that various modifications and variations are possible without departing from the scope of the technical idea of the present invention by anyone having ordinary skill in the art.

1 is a schematic view showing a low pollution hollow fiber membrane module according to an embodiment of the present invention;

2 is a schematic view showing the lower barrier member 108 and the separate particle collecting unit 105 according to an embodiment of the present invention;

3 is a schematic view showing the lower blocker 108 and the hollow fiber membrane 101, the separating particle moving hole 106, the rotary distribution plate 104 of the low pollution hollow fiber membrane module;

4 is a schematic view showing the inflow nozzle 103, the rotary distribution plate 104, and the inflow distribution port 112. And

Figure 5 is a schematic diagram showing an apparatus for applying a low pollution hollow fiber membrane module according to an embodiment of the present invention in water treatment.

<Explanation of symbols for the main parts of the drawings>

101: hollow fiber membrane 102: case

103: inlet nozzle 104: rotary distribution plate

105: separation particle collecting unit 106: separation particle moving port

107: separation particle outlet 108: lower barrier material

109: top barrier 110: concentrated water nozzle

111: treated water nozzle 112: inflow water distribution port

501: raw water inlet piping 502: membrane inlet collection tank

503: inflow control valve 504: strainer

505: influent feed pump 506: low pollution hollow fiber membrane module

507: separate particle outlet 508: compressor

509: treatment water discharge pipe 510: treatment water tank

511: chemical tank 512: backwash pump

513: regulator 514: backwash adjustment valve

515: backwash valve 516: air discharge valve

517: concentrated water circulation piping 518: backwash water discharge piping

519: membrane inflow pipe

Claims (8)

A hollow fiber membrane, a case for protecting the hollow fiber membrane and maintaining the filtration pressure, a lower barrier for separating the treated water and the influent, an upper barrier for separating the treated and concentrated water, an influent nozzle for introducing the influent into the membrane module, concentration In the low pollution hollow fiber membrane module including a concentrated water nozzle for discharged water, and a treated water nozzle for discharged treated water, A rotating distribution plate for introducing the introduced influent into the module while contacting the hollow fiber membrane and inducing foreign substances having a specific gravity different from that of the influent to be separated by centrifugal force; An inflow water distribution port for implementing an even distribution so that the inflow water does not flow unevenly within the module; A separation particle collecting unit in which the separation particle is integrated through the separation particle moving hole without contacting the hollow fiber membrane of the module; And Low pollution hollow fiber membrane module, characterized in that it comprises a discharge particle outlet for discharging the collected separation particles to the outside of the system. The method of claim 1, The upper and lower barrier members are polymer adhesives, and soft nitriding proceeds from the edges of both ends of the low pollution hollow fiber membrane module to prevent the low pollution hollow fiber membrane from being cut at the contact portion with the adhesive. Low pollution hollow fiber membrane module. The method of claim 1, The rotary distribution plate is installed in a circular shape along the lower case inside the lower case of the module to induce the inflow of the rotation flow along the outer surface of the rotary distribution plate to remove some or all of the foreign matter Low pollution hollow fiber membrane module characterized in. The method of claim 1, The separation particle collecting unit is installed in the lower portion of the low pollution hollow fiber membrane module, the low pollution hollow fiber membrane module, characterized in that the separation particle moving hole is installed in the lower barrier member to collect the foreign matter. The method according to any one of claims 1 to 3, The rotary distribution plate is a low pollution hollow fiber membrane module characterized in that there is no influent distribution hole in the front of the inlet nozzle and the inflow distribution is evenly generated by increasing the size of the influent distribution hole as it moves away from the inlet nozzle. A hollow fiber membrane, a case for protecting the hollow fiber membrane and maintaining the filtration pressure, a lower barrier for separating the treated water and the influent, an upper barrier for separating the treated and concentrated water, an influent nozzle for introducing the influent into the membrane module, concentration A water pollution apparatus using a low pollution hollow fiber membrane module including a concentrated water nozzle through which water is discharged and a treated water nozzle through which treated water is discharged, the low pollution hollow fiber membrane module includes: A rotating distribution plate for introducing the introduced influent into the module while contacting the hollow fiber membrane and inducing foreign substances having a specific gravity different from that of the influent to be separated by centrifugal force; An inflow water distribution port for implementing an even distribution so that the inflow water does not flow unevenly within the module; A separation particle collecting unit in which the separation particle is integrated through the separation particle moving hole without contacting the hollow fiber membrane of the module; And Further comprising a separate particle outlet for discharging the collected separated particles out of the system, Water treatment device characterized in that to periodically remove the foreign matter collected in the separation particle collecting unit through the separation particle outlet. The method of claim 6, The water treatment is a water treatment apparatus comprising at least one of purified water treatment, reused water treatment, effluent treatment, effluent reuse treatment river maintenance water treatment, seawater desalination pretreatment, ship ballast water treatment, household reuse water treatment. 8. The method according to claim 6 or 7, Maintaining a certain time interval in removing the foreign matter collected in the separated particle outlet port to perform at least one of automatic discharge, automatic discharge by maintaining a constant membrane filtration pressure rising interval, and automatic discharge immediately after backwashing. Water treatment device.

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