KR100877635B1 - Wastewater treatment apparatus with composite separation membrane module - Google Patents

Abstract

The present invention relates to a wastewater treatment apparatus using a composite membrane module, comprising a first filtration module for filtering waste water and a second filtration module that is separated while filtering the primary filtration water treated by the first filtration module once more. The present invention relates to a wastewater treatment apparatus using an immersion type composite membrane module. The present invention relates to an immersion type wastewater treatment apparatus for filtering raw water, wherein the first module hollow fiber is installed in an I shape or a U shape on a concentric circle having a predetermined diameter. A first filtration module having an inner acid device for washing the membrane having a pipe shape having a plurality of through holes formed on a surface thereof, the center of the separator being fixed to a fixing member at an upper end and a lower end; An upper cap having a backwash water inlet pipe formed at a predetermined portion of a side of the main body which protrudes in an upward direction of the upper fixing member to form a treated water outlet for draining the treated water and has a screw formed on an inner circumferential surface of the lower end of the main body; The inside of the upper cap is characterized in that it comprises a second filtration module having a separation membrane is installed in the inner cylinder in which the opening corresponding to the inlet of the inner space portion is installed downward, and the drainage edge through which the filtered water filtered by the separation membrane.

Description

Wastewater treatment apparatus using composite separation membrane module             

1 is an exemplary view showing the structure of a wastewater treatment apparatus using a composite membrane module to which the technique of the present invention is applied.

Figure 2 is a longitudinal sectional view of the wastewater treatment apparatus using a composite membrane module showing another embodiment of the present invention.

3 to 4 is a longitudinal cross-sectional view of the wastewater treatment apparatus using a composite membrane module showing another embodiment of the present invention.

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

      1: Wastewater treatment device using composite membrane module

      2: first filtration module 3: second filtration module

      4: upper cap 20: first module hollow fiber membrane

     21: internal acid device for washing the membrane 22,22a: hollow fiber membrane support

     31: inner cylinder 32: the second module separator

     40: main body 41: treated water outlet

     42: backwash water inlet pipe

The present invention relates to a wastewater treatment apparatus using a composite membrane module, comprising a first filtration module for filtering waste water and a second filtration module that is separated while filtering the primary filtration water treated by the first filtration module once more. The present invention relates to a wastewater treatment apparatus using an immersion type composite membrane module.

Membranes for separating a mixture by selectively passing specific components have been widely used in various forms. One of them, the membrane module in the form of hollow fiber is widely used in each field because it has the advantage of having a large permeate flow rate in a small module, and in the industrial wastewater treatment field, the hollow fiber membrane module is immersed in the aeration tank during the biological wastewater treatment process. In this case, it is possible to keep the treated water quality in good condition regardless of the degree of microorganism settling, so it requires less chemicals and maintenance costs for microbial management, and it is possible to maintain high concentration of microorganisms in the aeration tank so that it can cope with the change of influent concentration. It is known to bring many advantages, such as the ability to do this, and the need for a sedimentation tank for separating solid-liquid liquid using gravity sedimentation.

Therefore, researches on hollow fiber membrane modules that can be used for aeration tanks in the United States, Japan, Canada, etc. have been actively conducted, and in fact, various types of hollow fiber membranes are actively applied.                         

However, the immersed hollow fiber membrane modules, which are devised and currently used, have serious problems. Conventional commercialized U-shaped modules have been introduced to remove solids and organic substances attached to hollow fiber membranes by injecting or giving up air from the lower part of the module or shaking the membrane using a stirrer when the membrane contamination progressed. .

However, at the boundary of the hollow fiber membrane and the adhesive Due to the poor durability, the hollow fiber membranes are cut off and the raw water is mixed with some of the unfiltered water. In particular, when the submerged hollow fiber membrane module is used as a pretreatment for the reverse osmosis (RO) device, deterioration of the water quality of the filtered water is a major cause of shortening the life of the reverse osmosis membrane.

Due to the problems described above, a lot of cost and time are consumed in the maintenance and repair of the wastewater treatment system, and even if the first cut hollow fiber membrane is repaired, the same problem may occur later. As the amount of air is inevitably reduced, the surface cleaning effect of the hollow fiber membrane is lowered, which reduces the amount of filtration and thus frequently performs the cleaning, thus costly and time-consuming to operate the submerged hollow fiber membrane module, and the economic efficiency is lowered. There is a problem.

Therefore, in the present invention, even when the first module hollow fiber membrane is damaged, the wastewater treatment apparatus can be operated smoothly, and the cost and time required for the maintenance, replacement and management of the module can be drastically reduced, thereby reducing wastewater efficiently and economically. It is to provide a wastewater treatment apparatus using a composite membrane module that can be treated.

An object of the present invention described above is an immersion type wastewater treatment apparatus for filtering raw water, wherein a plurality of through holes are formed on the surface of the first module hollow fiber separator installed in an I-shaped or U-shaped shape on a concentric circle having a predetermined diameter. A first filtration module in which an internal acid generator for washing the membrane having a pipe shape formed therein is fixed to a fixing member at an upper end and a lower end; An upper cap protruding in an upper direction of the upper fixing member and having a backwash water inlet pipe formed at a predetermined portion of a side of the main body to form a treated water outlet for draining the treated water, and having a screw formed on an inner peripheral surface of the lower end of the main body; The inside of the upper cap is characterized in that the separation membrane is installed in the inner cylinder in which the opening corresponding to the inlet of the inner space is installed downward, and comprises a second filtration module having a drain edge for the filtered water is filtered out by the separation membrane It is achieved by a wastewater treatment apparatus using a membrane module.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is an exemplary view showing a structure of a hollow fiber membrane wastewater treatment apparatus to which the technique of the present invention is applied, and according to the present invention, the present invention includes a first filtration module 2 and an upper cap 4 to filter raw water. It is composed of a second filtration module (3) for re-filtering the treated water.

The first filtration module 2 has a pipe shape in which a plurality of through holes are formed only in the upper and lower portions of the first module hollow fiber membrane 20 installed in an I or U shape on a concentric circle having a predetermined diameter. Internal membrane device 21 for washing the separation membrane having a structure made of a fixed epoxy resin to the hollow fiber membrane support (22, 22a) of the top and bottom.

At this time, the material of the first module hollow fiber membrane 20 is made of a polymer material such as polysulfone, polyethylene, polypropylene, polyacrylonitrile, the effective pore size of the membrane is 0.005 ~ 0.5㎛, effective membrane area is 1 ~ As 100 m <2> / module, it is preferable that the form is I or U shape.

On the other hand, the upper cap (4) is provided with a backwash water inlet pipe (42) in a predetermined portion of the side of the main body 40, which protrudes in the upward direction to form a treated water outlet 41 for draining the treated water. 40) The screw is formed on the inner circumferential surface of the bottom.

The second filtration module 3 is installed inside the upper cap 4, and the structure thereof has a second module separation membrane 32 installed in the inner cylinder 31 in which the opening corresponding to the inlet of the inner space is downwardly installed. And a drain edge 33 through which the filtered water filtered by the separation membrane 32 is discharged.

The second module separation membrane 32 has an effective pore diameter of 0.01 to 10 μm, an effective membrane area of 0.1 to 10 m 2 / module, and a material made of a polymer such as polysulfone, polyethylene, polypropylene, and polyacrylonitrile. desirable.

Looking at the coupling structure of the upper cap 4 and the second filtration module 3 in more detail to insert the second filtration module 3 inside the upper cap 4 in the downward direction of the treated water outlet 41 The discharge edge 33 is inserted and fixed upward, and an O-ring is installed between the inner surface of the treated water outlet 41 and the outer surface of the discharge edge 33 to prevent leakage.

On the other hand, Figure 2 is another embodiment of the present invention, the structure of the second module separation membrane 33a is installed in the inner cylinder 31, the surface of the micropore (micro pore) adhesive to the flat membrane 32a-1 By using a second embodiment of the second filtration module (3a) is formed by spirally winding the treated water pipe (32a) is formed in a pipe form formed with a plurality of holes (holes).

FIG. 3 shows a flat sheet having a micropore formed on the surface of the fixing groove 31a on the inner upper end of the upper cap 4 as another embodiment of the present invention. The second filtration module 3b is formed by installing the second module separation membrane 32b formed in the form of a plate by stacking the flat sheet 32b-1 in one or several layers.

In addition, as shown in Figure 4, the screw is formed on the outside of the upper end to be coupled by the coupling method by the upper cap (4) and the screw and the screw on the inner lower end to be coupled to the fixing member 22a in the same coupling method It is formed, it can also be used to cope with the second filtration module (3c) of the cartridge type is installed between the upper cap (4) and the fixing member (22a).

During backwashing, the backwash water flows in as the treated water outlet is closed and the backwash water inlet pipe 42 is opened, and because the treated water outlet is closed, the second filtration module is not cleaned (washed), but the first of the first filtration module 2. The module hollow fiber separator 21 is cleaned by backwashing. In addition, the first module hollow fiber membrane is washed by the internal acid device 22 for washing the membrane. The second filtration module is periodically replaced, it is preferable to use the effective pore size of the second module separation membrane 21 is formed of 0.01 ~ 10㎛, effective membrane area of 0.1 ~ 10m ² .

When explaining the operation and effect of the present invention the wastewater treatment device (1) having the structure as described above with reference to the accompanying drawings, Figure 1, the wastewater treatment device (1) using the composite membrane module of the present invention in a tank storing raw water When the first filtration module 2 is immersed in raw water and forced suction in the pump (not shown), the raw water is first filtered while the raw water passes from the outside to the inside when the first module hollow fiber membrane 21 is centered.

The primary filtered filtrate is moved toward the upper cap 4 via the hollow fiber membrane support part 22a and filled in the inner space of the upper cap 4. At this time, since the backwash inlet pipe 42 provided on the side of the upper cap 4 is closed, the filtered water continues to move upward.

As described above, the first filtered filtrate is secondarily filtered while passing through the second module separation membrane 32 in the inner cylinder 31 constituting the second filtration module 3 installed inside the upper cap 4. At this time, even if the first module hollow fiber membrane 21 constituting the first filtration module 2 is partially cut during operation and the water quality of the primary filtrate is deteriorated, the primary filtrate is filtered once more by the second module membrane 32. The filtered water is secondary filtered and discharged through the outlet 42 into which the drainage lead 33 is inserted so that there is no fear of deterioration of water quality, and leakage is prevented by an O-ring provided therebetween.

When the water treatment operation is performed to some extent, contaminants are gradually adhered to the outer wall of the first module hollow fiber membrane 21 so that the permeation rate passing through the first module hollow fiber membrane 21 is gradually reduced.

At this time, the first module hollow fiber membrane 21 is cleaned by abandoning the air through the internal acid generator 21 for washing the membrane in the form of a pipe. This removes contaminants adhering to the outer wall of the first module hollow fiber membrane 21.

As described above, the first module hollow fiber membrane 21 is first cleaned using air to remove contaminants adhering to the outer wall of the first module hollow fiber membrane 21, but backwashing is performed to further increase the cleaning effect. The washing water is introduced into the wastewater treatment apparatus of the present invention through the inlet pipe 42.

The backwashing by the backwashing inlet pipe 42 is performed only the first filtration module 2 without the second filtration module 3. Therefore, when the second hollow fiber membrane module 3 is periodically replaced, more stable filtered water can be obtained.

FIG. 2 shows another embodiment of the present invention, in which the filtered water filtered by the first filtration module 2 flows inward from the outside of the inner cylinder 31 to form a second module separation membrane 33a. Secondary filtration and secondary filtered filtrate passes through the flat membrane 32a-1 having micro pores and flows through the hole formed in the treated water pipe 32a and flows into the treated water pipe 32a. do.

The filtered water introduced into the inside of the treated water pipe 32a by the second filtration is not mixed with the filtered water first filtered by the closed treated water pipe 32a, and drained through the outlet by the pressure difference in this state. do.

Figure 3 is formed by forming a plate-like form by overlapping the flat sheet (32b-1) inserted into the fixing groove portion 31a of the inner upper end of the upper cap 4 in one or several layers. The two-module separation membrane 32b is moved from the lower side to the upper side while being filtered out.

In the case of FIG. 4, the filtration order and operation are the same as those of FIG. 1, but one side is screwed to the screw formed under the upper cap 4, and the other side is the second filtration module 3 in the same coupling manner to the fixing member 22a. The shape of the cartridge may be changed to a cartridge type so as to be coupled to the second filter module 3 to facilitate replacement and repair of the second filtration module 3.

Features and other advantages of the present invention as described above will become more apparent from the following examples. However, the present invention is not limited to the following examples.

Looking at the embodiment of the wastewater treatment apparatus using the composite membrane module of the present invention configured and operated as described above,

Example 1

An inner diameter of 100 mm, a length of 600 mm, a first filtration module (2) made of a PVC material was prepared. Inside, the first module hollow fiber membrane 21 having an inner diameter of 700 μm and an outer diameter of 1000 μm is embedded with 4000 strands in an I-shape, and both ends thereof are fixed to the hollow fiber membrane support parts 22 and 22a. Resin was used.

And the second filtration module 3 was made of an inner diameter of 70mm, length 80mm, PVC material. Inside the manufactured second filtration module 3 has an inner diameter of 250 μm and an outer diameter of 400 μm and is made of the same material as the first module hollow fiber membrane 20 of the first filtration module 2. The second module separator 32 was installed.

The second filtration module 3 and the first filtration module 2 are combined to immerse the module of the present invention in a tank (reactor) of 400 l and using a suction pump (-) 100 to (-) 500 mmHg (not shown). It was operated at a pressure of to obtain permeate of 0.7 L / min.

In order to prevent the contamination of the membrane at the same time as the suction filtration, the washing air was supplied at a flow rate of 150 l / min from the internal membrane device 22 for washing the membrane of the first filtration module 2 to perform the washing by shaking the membrane. Wastewater of chemical oxygen demand (COD) 600 (mg / L), biochemical oxygen demand (BOD) 500 (mg / L) and suspended solids (SS) 60 (mg / L) was used as the feed water. Operation conditions were air cleaning for 2 minutes after 30 minutes of operation and backwashing with water after 6 hours of operation. At this time, the suspended solids (SS) of the raw water and the filtered water were analyzed once per week to confirm the change of the water quality of the filtered water according to each operation time.

Example 2

Inside the first filtration module 2 of PVC material having an inner diameter of 100 mm and a length of 600 mm, there are built 4000 strands of the first module hollow fiber membrane 21 having an inner diameter of 700 μm and an outer diameter of 1000 μm, and both ends are bonded with epoxy. do. On the other hand, the second filtration module 3 is a flat membrane 32a-1 having a micro pore of 0.6 μm on the surface of the second module separation membrane 33a installed in the inner cylinder 31 using an adhesive. One embodiment using the second filtration module (3a) formed by spirally wound around the treated water pipe (32a) in the form of a pipe formed with a plurality of holes.

At this time, the operating conditions are the same as in Example 1, and the suspended solids (SS) of the raw water and the treated water were analyzed once per week to confirm the change in the water quality of the filtered water according to each operation time.

Example 3

An inner diameter of 100 mm and a length of 600 mm, the first filter module 2 of PVC material was prepared. Inside the module, 4000 strands of the first module hollow fiber membrane 21 having an inner diameter of 700 µm and an outer diameter of 1000 µm were embedded. Both ends are modules bonded with epoxy and hollow fiber membrane is made in I-shape. The second module separation membrane 32b is a module made of PVC material having an inner diameter of 118 mm and a length of 80 mm. Inside the module, a second module separation membrane 32 having a diameter of 300 µm and an outer diameter of 500 µm having the same material as that of the first module hollow fiber membrane is installed with 15000 strands having a U shape.

At this time, the operating conditions are the same as in Example 1, by analyzing the suspended solids (SS) of raw water and treated water once per week to confirm the change in the water quality of the filtered water according to each operation time.

Comparative Example 1

Using the existing submerged hollow fiber membrane module to operate the raw water in the same conditions as in the embodiment, the suspended solids (SS) of the raw water and treated water was analyzed once per week to check the hollow fiber cutting of the submerged module. Table 1 shows the experimental results of Examples 1, 2 and 3 and Comparative Example 1.

Elapsed Week Suspended solids (mg / L) Example 1 Example 2 Example 3 Comparative Example 1 0 0.4 0.2 0.5 0.5 One 0.3 0.3 0.4 0.7 2 0.5 0.6 0.3 0.3 3 0.3 0.5 0.4 0.4 4 0.3 0.3 0.5 0.7 5 0.2 0.3 0.2 0.2 6 0.3 0.4 0.4 0.4 7 0.5 0.7 0.6 0.6 8 0.4 0.6 0.5 0.5 9 0.6 0.3 0.3 0.7 10 0.4 0.5 0.2 0.5 11 0.2 0.4 0.3 0.8 12 0.5 0.3 0.6 2.6 13 0.3 0.3 0.5 5.9 14 0.4 0.6 0.4 11.8 15 0.2 0.2 0.4 18.9 16 0.3 0.2 0.3 22.6

Compared to the conventional immersion type module having the form of a composite membrane module according to the present invention, it is possible to obtain stable water quality for a long period of time without being affected by the cutting of the first module hollow fiber membrane, and when the first module hollow fiber membrane is broken, Economical system operation can be achieved by drastically reducing the time and cost required for repair and maintenance.

Claims (10)

In the immersion type wastewater treatment apparatus for filtering raw water, In the center of the first module hollow fiber membrane installed in a concentric circle having a predetermined diameter in an I-shaped or U-shaped shape, an internal diffuser for washing the membrane having a pipe shape having a plurality of through-holes formed on its surface is provided with fixing members at the upper and lower ends. A first filtration module fixed to the; An upper cap having a backwash water inlet pipe formed at a predetermined portion of a side of the main body which protrudes in an upward direction of the upper fixing member to form a treated water outlet for draining the treated water and has a screw formed on an inner circumferential surface of the lower end of the main body; The inside of the upper cap is characterized in that the separation membrane is installed in the inner cylinder in which the opening corresponding to the inlet of the inner space is installed downward, and comprises a second filtration module having a drain edge for the filtered water is filtered out by the separation membrane Wastewater treatment device using a membrane module. The wastewater treatment apparatus according to claim 1, wherein the first module hollow fiber membrane is made of any one polymer material selected from polysulfone, polyethylene, polypropylene, and polyacrylonitrile. The wastewater treatment apparatus according to claim 1, wherein an effective pore diameter of the first module hollow fiber membrane is 0.005 to 0.5 µm and an effective membrane area is 1 to 100 m 2 / module. The wastewater treatment apparatus according to claim 1, wherein the second filtration module is detachably installed inside the upper cap. The wastewater treatment apparatus of claim 1, wherein the membrane of the second filtration module is made of any one material selected from polymer materials such as polysulfone, polyethylene, polypropylene, and polyacrylonitrile. . The wastewater treatment apparatus according to claim 1, wherein the membrane of the second filtration module has an effective pore size of 0.01 to 10 µm and an effective membrane area of 0.1 to 10 m 2 / module. The composite membrane module according to claim 1, wherein the separation membrane of the second filtration module installed in the inner cylinder is a treated water pipe formed by spirally wound a flat membrane having micro pores on the surface of the pipe. Wastewater treatment device using. The wastewater treatment apparatus according to claim 1, wherein the shape of the second filtration module is a cartridge type coupled between the upper cap and the first filtration module. The method of claim 1, wherein the separation membrane of the second filtration module forms a fixing groove at an inner upper end of the upper cap, and the fixing groove has a flat sheet having micro pores on the surface thereof. Wastewater treatment apparatus using a composite membrane module, characterized in that formed in the form of a plate overlapping multiple layers. delete

Images