KR102076202B1 - Seawater desalination apparatus - Google Patents

Abstract

A seawater desalination apparatus is provided. The seawater desalination apparatus according to an embodiment of the present invention includes an electrocoagulation module for electrocoagulating suspended solids contained in the inflowed seawater, and a filter module for filtering aggregates contained in the electrocoagulation water introduced from the coagulation module. A preprocessing unit; And an osmosis filtration unit having an osmosis membrane module for desalination of the pretreatment water introduced from the pretreatment unit. According to this, by effectively agglomeration of foreign matter contained in seawater or brackish water, and then processing the aggregated foreign matter at a high speed to discharge at a high flow rate, to increase the desalination flow rate and to significantly improve the durability of the osmotic equipment for desalination. Can be. In addition, since it is possible to remove foreign matters without additional chemical additives in the pretreatment of seawater or brackish water, it is environmentally friendly, and it is easy to backwash process to remove foreign matters collected by pretreatment, and its durability is extended for its use. It has a cycle and is very economical to operate.

Description

Seawater desalination apparatus

The present invention relates to a seawater desalination apparatus, and more particularly, to improve the pretreatment efficiency for seawater, which is raw water, to reduce the damage of the osmosis module for desalination, and to increase the freshwater amount accordingly as the pretreatment rate is very fast. It relates to a desalination device.

Seawater desalination is a series of water treatment processes that removes dissolved substances, including salts, from seawater, which cannot be directly used for domestic or industrial water, to obtain high-purity drinking water, domestic water, and industrial water. In other words, seawater desalination means the removal of salt from seawater containing salt to obtain fresh water.

Such seawater desalination methods include evaporation using water evaporation phenomena, membrane filtration using membrane differentiation and selective passage ability, and membrane filtration is classified into reverse osmosis and electrodialysis in detail.

Reverse osmosis (RO) accounted for about 48% of the total desalination market until 2005, but replaced the existing evaporation method by more than 70% in 2020 due to rising energy costs. This is expected to increase. The reverse osmosis method separates the components contained in seawater or brackish water into produced water (or treated water) and concentrated water by using a polymer membrane (reverse osmosis membrane), and the produced water is diluted with the concentration of components and used as drinking water and drinking water. The brine is discharged back to the sea. The reverse osmosis membrane used in the reverse osmosis method requires a very fine pore structure that can remove salts, including pressure resistance capable of withstanding high pressure applied in excess of about 25 kg / cm 2 of osmotic pressure of seawater so that reverse osmosis occurs. . Recently, osmosis has been used for seawater desalination, but seawater desalination has been continued through forward osmosis.

On the other hand, seawater, which is raw water, contains a large amount of foreign matter, such as small algae, suspended matter, and a large amount of foreign matter. When the seawater is subjected to an osmotic process with such foreign matters, Durability is greatly reduced, and frequent pressure correction due to the deepening of fouling phenomenon should be prevented from introducing foreign matter into reverse osmosis process to the maximum.

To this end, it is preferable to inject the seawater collected into the osmosis process with large contaminants or foreign substances removed through pretreatment, and a membrane filtration method including filter media such as hollow fiber membranes has been used as a pretreatment facility. However, through this, there is a problem that the flow rate is not sufficient and the time required for pretreatment is extended or the amount of fresh water obtained is very small. In addition, there is a problem that the backwashing efficiency for removing various foreign matters adsorbed on the membrane is low, and the durability to sufficiently perform the backwashing is not secured.

As a result, a sufficient flow rate is obtained in the pretreatment process, and the removal rate of foreign substances is excellent, and therefore, it is urgent to develop a seawater desalination apparatus that can desalination of seawater in an environmentally friendly manner.

Republic of Korea Patent Publication No. 10-1051345

The present invention has been made in view of the above, by effectively agglomeration of foreign matter contained in seawater or brackish water as raw water, and then processing the aggregated foreign matter at high speed to discharge at a high flow rate, increasing the desalination flow rate and desalination An object of the present invention is to provide a pretreatment facility for a seawater desalination apparatus and a seawater desalination apparatus having the same, which can significantly improve the durability of the osmosis system.

In addition, the present invention is environmentally friendly, it is easy to backwash process for removal of the foreign matter collected by the pretreatment, since the foreign matter can be removed without a separate chemical additive in the pretreatment of sea water or brackish water, durability is high Another object of the present invention is to provide a pretreatment facility for a seawater desalination apparatus having an extended use cycle and very economical in operation, and a seawater desalination apparatus having the same.

In order to solve the above problems, the present invention is a pre-treatment unit including an electric coagulation module for electroaggregating foreign matter contained in the seawater introduced, and a filter module for filtering the aggregates contained in the electrocoagulation water introduced from the electrocoagulation module ; It provides a seawater desalination device comprising; and an osmosis filtration unit having an osmosis membrane module for desalination of the pretreatment water introduced from the pretreatment unit.

According to an embodiment of the present invention, the electrocoagulation module electroaggregates foreign matters contained in seawater through cations generated at the sacrificial electrode, and the processing capacity of the inflowed seawater may be 1 m ³ / h or more.

In addition, the filter module is provided with a plurality of filter units having a filter medium, the filter medium is in the aggregate with a filtration flow rate of 50 LMH or more and a particle size of 0.2 ㎛ or more with respect to the electric coagulation water flowing from the electrocoagulation module The filtration efficiency may be greater than 99%.

In addition, the filter medium is a flat membrane having a second support and a nanofiber web stacked on both surfaces of the first support, respectively, and a flow path in which the filtrate filtered from the nanofiber web flows in the direction of the first support is formed. It may be.

In addition, the first support and the second support may each independently be any one or more of a nonwoven fabric, a woven fabric and a knitted fabric, more preferably a nonwoven fabric.

In addition, the basis weight of the nanofiber web is 30g / ㎡ or less, the basis weight of the first support is 250 g / ㎡ or more, the thickness may be 90% or more of the total thickness of the filter medium.

In addition, the basis weight of the first support may be 250 ~ 800g / ㎡, more preferably 350 ~ 600g / ㎡. In addition, the thickness of the first support may be 2 to 8 mm, more preferably 2 to 5 mm, even more preferably 3 to 5 mm.

In addition, the basis weight of the second support is 35 ~ 100g / ㎡, the thickness may be 150 ~ 250㎛.

In addition, the nanofiber web includes a fluorine-based compound as a fiber forming component, the fluorine-based compound is polytetrafluoroethylene (PTFE) -based, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymerization system, tetrafluoroethylene- Hexafluoropropylene copolymerization system, tetrafluoroethylene-hexafluoropropylene-perfluoroalkyl vinyl ether copolymerization system, ethylene-tetrafluoroethylene copolymer (ETFE) system, polychlorotrifluoroethylene (PCTFE) system, It may include any one or more compounds selected from the group consisting of ethylene-chlorotrifluoroethylene copolymer (ECTFE) system and polyvinylidene fluoride (PVDF) system.

In addition, the nanofiber web has an average pore diameter of 0.1 to 5㎛, porosity may be 60 to 90%.

In addition, the nanofibers forming the nanofiber web may have an average diameter of 0.05 ~ 1㎛.

In addition, the basis weight of the nanofiber web may be 0.05 ~ 20g / ㎡.

The second support further includes a second composite fiber including a support component and a low melting component such that at least a portion of the low melting component is exposed to an outer surface, and the low melting component of the second composite fiber is The second support and the nanofiber web may be bonded by fusion to the nanofiber web.

The first support member of the filter medium may include a first composite fiber including a support component and a low melting point component such that at least a portion of the low melting point component is exposed to an external surface, and the low melting point of the first composite fiber. The first support and the second support may be joined by fusion between the component and the low melting point component of the second composite fiber.

The filter unit may be a flat filter unit further including a support frame supporting the edge of the filter medium, and the support frame may include a flow path for allowing the filtrate filtered from the filter medium to flow out.

In addition, the electrocoagulation module, the housing having an inner space of the upper open; And an electrode unit disposed in the inner space and including a sacrificial electrode and a power electrode for agglomerating foreign substances contained in raw water supplied from the outside, wherein the inner space includes: a first chamber into which the raw water flows; The second chamber may be disposed on an upper side of the first chamber, and the third chamber may be temporarily stored in the second chamber in which the electrode unit is disposed, and the electrocoagulation water in which the electrocoagulation reaction is completed in the second chamber.

In addition, the present invention is an electroaggregation module for electroaggregating foreign matter contained in the introduced seawater; It provides a pre-treatment facility for a seawater desalination device comprising a; and a filter module for filtering the aggregates contained in the electrocoagulation water flowing from the electrocoagulation module.

According to the present invention, by effectively agglomeration of foreign matter contained in seawater or brackish water as raw water, and then treating the aggregated foreign matter at high speed and discharging it at a high flow rate, increasing the desalination flow rate and significantly increasing the durability of the osmotic facility for desalination. Can be improved. In addition, since it is possible to remove foreign matters without additional chemical additives in the pretreatment of seawater or brackish water, it is environmentally friendly, and it is easy to backwash process to remove foreign matters collected by pretreatment, and its durability is extended for its use. It has a cycle and is very economical to operate.

1 is a schematic diagram of a seawater desalination apparatus according to an embodiment of the present invention,
2 is a schematic view showing an electrocoagulation module included in an embodiment of the present invention;
3 is a view showing the main configuration of FIG.
Figure 4 is a partial cutaway view showing the internal structure of the housing in Figure 3,
5 is a cross-sectional view of FIG.
6 is a schematic view showing a case in which the diffuser is included in FIG.
7 is a cross-sectional view of FIG.
8 is a schematic view showing an inlet pipe applied to the electrocoagulation module included in an embodiment of the present invention;
Figure 9 is a schematic diagram showing the diffuser applied to the electrocoagulation module included in an embodiment of the present invention,
10 is a view showing the main configuration of the electrocoagulation module included in another embodiment of the present invention,
11 is an exploded view of FIG. 10;
12 is a bottom view showing an electrode case applied to FIG. 10;
13A and 13B are views of a flat plate filter unit that may be provided in a filter module included in an embodiment of the present invention. FIG. 13A is a perspective view of the filter unit, and FIG. 13B is a sectional view taken along the line XX ′ of FIG. 13A. Schematic diagram showing filtration flow as a reference,
15 is a cross-sectional view of the filter medium provided in the filter module included in an embodiment of the present invention;
16 is a surface electron micrograph of the nanofiber web applied to the filter medium included in an embodiment of the present invention,
17 is a photograph of a filter medium in which the washing solution is trapped inside the filter medium and swells after being separated in the filter medium by a backwashing process.
FIG. 18 is a schematic diagram illustrating directly laminating a first support and a nanofiber web as an example of a filter medium; FIG.
19A and 19B are schematic views of laminating the filter medium included in the embodiment of the present invention, and FIG. 19A is a view showing laminating the nanofiber web and the second support, and FIG. A drawing showing that the second support is placed on both sides of the first support and laminated,
20 to 23 is a cross-sectional view of another filter medium provided in the filter unit included in an embodiment of the present invention, and
24 is a partial exploded perspective view of an osmotic unit provided in an osmotic filtration unit included in an embodiment of the present invention, and
25 is an exploded perspective view illustrating the internal components of the osmotic unit according to FIG. 24 from which the outer housing is removed.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. The drawings and description are to be regarded as illustrative in nature and not restrictive. Like reference numerals designate like elements throughout the specification.

Seawater desalination apparatus according to an embodiment of the present invention is a pre-treatment unit 3200 for filtering foreign substances and the like contained in the seawater withdrawn as shown in Figure 1 and the osmosis filtration unit 3300 to remove salts and the like contained in seawater ), And may further include a supply pump 3100 for supplying the collected seawater to the pretreatment unit 3200. In addition, although not shown in Figure 1 intake pump for taking sea water or brackish water, raw water storage tank in which the collected sea water is stored, the storage tank in which pre-treated electrocoagulated water is stored in the pretreatment unit 3200, produced in the osmosis filtration unit 3300 A facility may be further provided in a known seawater desalination apparatus, such as a post-treatment facility in which the produced water is post-treated or a water treatment tank in which the post-treated purified water is stored.

The pretreatment unit 3200 removes various suspended substances such as microorganisms such as algae contained in raw water or algae, ions, salts and colloidal substances formed by binding ions to a predetermined level or more. It raises, reduces the filtration burden on an osmotic filtration part, and plays a role which improves the durability of an osmotic filtration part significantly.

To this end, the pretreatment unit 3200 includes an electroaggregation module 3210 for electrocoagulating the suspended substances contained in the introduced seawater, and a filter for filtering the aggregates contained in the electrocoagulation water introduced from the electrocoagulation module 3210. Module 3220.

The electrocoagulation module 3210 aggregates charged foreign matters among suspended matters contained in raw water or sea water through ions having opposite charges to form aggregates or to deposit foreign matters in the electrochemically generated aggregates. An electroaggregation process of foreign matter is carried out by adsorption.

The electrocoagulation module 3210 may be employed without limitation in the case of an electrocoagulation device known to perform such a process. However, preferably, the electrocoagulation module 3210 may have a processing capacity of 1 m ³ / h or more of the introduced raw water so as to process a large amount of raw water in a short time.

The electrocoagulation module 3210 may include, for example, an electrode unit including a housing having a predetermined empty internal space for accommodating incoming raw water and performing an electrocoagulation reaction of foreign matter, and a sacrificial electrode for generating cations. It may include.

The size of the housing, the thickness of the outer wall, the volume / structure of the internal space, etc. are known electroaggregation in consideration of the capacity of the raw water to be treated, the type / content of the foreign matter contained in the raw water, and the treatment method of the electroaggregated foreign matter. The present invention is not particularly limited thereto as the device may be adopted or modified appropriately according to the purpose.

The electrode unit may further include a sacrificial electrode capable of directly generating an electroaggregation reaction with a foreign material or indirectly generating a cation that mediates the electroaggregation reaction, and further comprising a power electrode that enables the sacrificial electrode to generate cations. Each of the sacrificial electrode and the power electrode may be provided in an appropriate form, size, weight, and number in consideration of processing capacity and processing speed of raw water.

The sacrificial electrode may be used without limitation in the case of a material capable of generating a cation by an applied power source. As a non-limiting example, the sacrificial electrode may be made of aluminum, iron, lithium, zinc and nickel, or an alloy thereof. Can be. In addition, the power electrode is preferably a material insoluble in the power applied from the outside, for example, may be stainless steel.

When a predetermined voltage is applied to the sacrificial electrode of the electrode unit, the sacrificial electrode is dissolved to elute metal ions into raw water, and the metal ions agglomerate with foreign substances of opposite charges contained in the raw water or the metal hydroxide is a solid aggregate of metal ions. After the formation of the foreign matter is adsorbed to the metal hydroxide foreign matter can be electro-aggregated.

The electrocoagulation module 3210 may have such a structure as to facilitate the electrocoagulation reaction, and to more easily remove the aggregated foreign matter.

The electrocoagulation module 100, 100 ′, 200 according to an embodiment of the present invention may include a housing 110, 210 and an electrode unit 120 as shown in FIGS. 2 to 12.

The housings 110 and 210 are for providing a space for temporarily storing the raw water supplied from the outside. To this end, the upper portion may have a shape of an enclosure having an open inner space. That is, the housing (110, 210) after the foreign matter contained in the raw water introduced from the outside through the agglomeration reaction, the internal space that is the residence space of the raw water can be formed so that the raw water can be transferred to a separate processing space side. .

To this end, the inner space is the first chamber 111 into which the raw water flows, the second chamber 112 in which the electrode unit 120 is disposed, and the treated water in which the electrocoagulation reaction is completed in the second chamber 112. It may include a third chamber 113 temporarily stored.

In this case, the second chamber 112 in which the electrode unit 120 is disposed may be formed at an upper side of the first chamber 111, and the third chamber 113 may be formed of the first chamber 111. The second chamber 112 and the third chamber 113, which may be formed side by side and arranged in parallel to each other, may be partitioned from each other via a partition wall 114 protruding to a predetermined height in the inner space. have.

Accordingly, the first chamber 111 serves as a buffer space that remains before the raw water supplied from the outside moves to the second chamber 112 where the electrocoagulation reaction is performed. It can move to the two chamber 112 side. As a result, the raw water flowing into the second chamber 112 may be brought into contact with the sacrificial electrode 122 and the power electrode 121 constituting the electrode unit 120 with a uniform area, thereby increasing the overall processing speed.

Here, the raw water supplied from the outside by the hollow inlet tube 130 having a predetermined length and the plurality of injection holes 131 formed along the longitudinal direction is disposed on the side of the first chamber 111. ) May be ejected toward the first chamber 111 (see FIGS. 4 and 8), and the inlet pipe 130 may be parallel to an arrangement direction of a plurality of electrodes constituting the electrode unit 120. Can be arranged. In addition, a drain discharge hole 118 connected to the drain pipe 119 may be formed on the bottom surface of the first chamber 111 to discharge the drain to the outside.

As such, the electroaggregation module 100, 100 ′, 200 according to the present invention uses raw water injected into the first chamber 111 through the injection hole 131 of the inlet pipe 130 to the first chamber 111. After completely filling, the water level gradually increases to flow into the second chamber 112 where the electrode unit 120 is disposed, and the raw water introduced into the second chamber 112 while maintaining the water level is equal to the electrode unit 120. After the agglomeration reaction is completed through the through) may be introduced into the third chamber 113 side beyond the upper end of the partition wall 114 from the second chamber (112).

In this case, the partition wall 114 may have one surface constituting the wall surface of the third chamber 113 as an inclined surface. For example, the inclined surface may be formed to be inclined downward toward the third chamber 113 toward the lower side from the upper end of the partition 114 (see FIGS. 2 to 4). Accordingly, the treated water overflowed through the upper end of the partition wall 114 may be smoothly moved toward the third chamber 113 along the inclined surface.

In addition, at least one discharge hole 118 may be formed on the bottom surface of the third chamber 113. The discharge hole 118 is connected to the after-treatment device for treating the foreign matter aggregated through the electrocoagulation reaction through a separate pipe 40, the treated water can be transferred to the after-treatment device.

On the other hand, the housing (110, 210) may be made of an insulator or a non-conductor to prevent a short with the electrode unit 120 disposed on the second chamber 112 side when the power is applied. For example, the housings 110 and 210 may be made of a material such as plastic, concrete, plywood, and the like, but the present disclosure is not limited thereto, and all known insulators or insulators may be used.

In addition, the outer surface of the housing (110, 210) by applying a coating layer having at least one of the properties of chemical resistance, corrosion resistance and electrical heat resistance to prevent the damage to the housing (110, 210) by heavy metals contained in raw water. Can be.

Such housings 110 and 210 may be fixed through a separate support frame 160. When the support frame 160 is included, the control unit 140 to be described later may also be fixed to one side of the support frame 160. have.

The electrode unit 120 may be provided with a plurality of plate-shaped electrodes having a predetermined area, and the plurality of electrode plates may be spaced apart from each other at a predetermined interval inside the second chamber 112. For example, the plurality of electrode plates may be parallel to each other such that one surface faces each other at a predetermined interval between the pair of power electrodes 121 to which power supplied from the outside is applied and the pair of power electrodes 121. It may include a plurality of sacrificial electrodes 122 are spaced apart from each other.

The pair of power electrodes 121 are formed to have a relatively longer length than the sacrificial electrode 122 so that power supplied from the outside can be smoothly applied. At least a portion of the length of the raw water may be exposed to the outside without being completely immersed in the raw water stored in the second chamber 112 (see FIG. 3). On the other hand, the plurality of sacrificial electrodes 122 disposed between the pair of power electrodes 121 are disposed so as to be completely submerged by the raw water stored in the second chamber 112, so that the entire area is in contact with the raw water to reduce the reaction area. It can be maximized.

On the other hand, the sacrificial electrode 122 and the power electrode 121 constituting the electrode unit 120 may be directly fixed to the housing 110, the second chamber 112 after being fixed to a separate member side The separate member may be coupled to the side.

For example, the electrode unit 120 may be directly fixed to the inner wall of the housing 110, as shown in Figs. That is, the inner wall of the housing 110 defining the second chamber 112, more specifically, the inner surface of the partition wall 114 facing each other and the inner surface of the housing 110 may include a plurality of fitting grooves 115 along the height direction. ), The plurality of fitting grooves 115 may be formed in a number corresponding to the power electrodes 121 and the sacrificial electrodes 122 provided in the electrode unit 120.

Here, the insertion groove 115 may be limited in the insertion depth of the lower end of the electrode unit 120 by the upper end is opened and the lower end is sealed.

Accordingly, by inserting the electrode unit 120 into the fitting groove 115, each of the neighboring electrodes can be arranged in parallel with one surface facing each other at a predetermined interval.

As another example, as shown in FIGS. 10 to 12, the electrode unit 120 is fixed to the electrode case 116, and then the electrode case 116 is disposed on the second chamber 112 side of the housing 210. It can also be fixed in a coupled manner.

In this case, the electrode case 116 may have a plurality of fitting grooves 117 formed in the inner wall facing each other along the height direction, the upper and lower portions may have an open shape. Accordingly, when the electrode case 116 is inserted into the second chamber 112 in the state in which the electrode unit 120 is inserted into each of the fitting grooves 117, the first chamber 111 is opened through the lower portion thereof. Raw water rising from) can flow smoothly.

Here, the electrode case 116 may be formed of an insulator or a non-conductor to prevent a short with the electrode unit 120 is inserted into the fitting groove 117 when the power is applied. For example, the electrode case 116 may be made of a material such as plastic, concrete, plywood, etc., but the present invention is not limited thereto, and all the known insulators or insulators may be used. In addition, a coating layer having at least one of chemical resistance, corrosion resistance, and electrical conductivity is applied to the outer surface of the electrode case 116, thereby preventing the electrode case 116 from being damaged by heavy metals contained in raw water. It can also be prevented.

As another example, as shown in FIGS. 13A and 13B, the electrode unit of the electrocoagulation module 200 ′ is disposed to face each other on the outer side of the receiving member 123, so that power supplied from the outside is applied. The conductive mass 122 ′ may be accommodated in the housing member 123 instead of the electrode plate by the power electrode 121 ′, which is a pair of electrode plates, and the sacrificial electrode 122 described above. As the sacrificial electrode 122, the metal cations eluted from the conductive mass 122 ′ provided in place of the plate-shaped electrode plate are electrically neutralized with the charged foreign matter, thereby causing the coagulation reaction and the oxidation and reduction reaction to remove the foreign matter. Can be. Since such electrocoagulation principle is well known, including the above description, a detailed description thereof will be omitted.

In the case of the electrode unit 120 of the type illustrated in FIGS. 1 to 12, a plurality of sacrificial electrodes 122 are spaced apart from each other between electrode plates, which are power electrodes 121 facing each other, and a power electrode to which power is applied. There is a concern that the difference in power consumption occurs depending on the relative distance from the power supply, and the consumption of power is rather large, thus increasing the production cost. On the contrary, when the sacrificial electrode is provided with a plurality of conductive masses 122 'as shown in FIGS. 13A and 13B, the electroaggregation efficiency of the equivalent level or more can be expressed while significantly reducing the power consumption. Furthermore, it may be more suitable for seawater desalination.

In detail, the conductive mass 122 ′ may be accommodated in the receiving member 123, and a pair of electrode plates that are the power electrodes 121 ′ may be disposed outside the receiving member 123 to face each other. In addition, the receiving member 123 is at least one first through-hole 123b for introducing the raw water from the first chamber 111 to the receiving space side of the receiving member, and through the first through-hole (123b) At least one second through hole 123a may be formed through each of the two electrodes plate 121 ′ facing the introduced raw water.

For example, the accommodating member 123 may be provided in the shape of an enclosure having an open top, the first through hole 123b may be formed on the bottom surface, and the second through hole 123a is the power. It may be formed through the side facing the electrode 121 '.

Accordingly, the raw water introduced into the receiving member 123 through the first through hole 123b may surround the surface of the conductive mass 122 'filled in the receiving member 123, and the second It may also be in contact with the power electrode 121 'through the through hole 123a.

Thus, when power is applied to the power electrode 121 'side, the plurality of conductive masses 122' filled in the receiving member 123 may be subjected to a constant voltage through raw water, thereby causing the above-described electroaggregation reaction to occur. have.

13A and 13B illustrate the receiving member 123 and the power electrode 121 ′ to be introduced into the housing 110 through the electrode case 116 ′. Alternatively, the electrode case functions as the receiving member. It is possible to change the design to serve. Specifically, the lower surface of the electrode case may have a shape that does not open to accommodate the conductive mass 122 ′ in the inner space, and a plurality of holes are formed in the lower surface so that raw water flows into the inner space. One through hole can be provided. In addition, the pair of power electrodes 121 'provided to face each other on both sides of the electrode case and the conductive mass 122' accommodated therein are in direct contact with the power electrode 121 'to prevent conduction. ) Is provided in the inner space of the electrode case to face the two separation plates facing each other, but the raw water introduced into the inner space of the electrode case passes through the separation plate and flows into the two electrode plates toward the two electrode plates. The second through hole formed through the hole can be provided. In addition, the separator may be an insulator or an insulator to electrically insulate the power electrode 121 'from the conductive mass 122'. On the other hand, there is no electrode case, provided with a groove or the like in the housing directly lead the power electrode 121 'to face each other, the space between the receiving member 123 and the receiving member 123 in the space therebetween It is also possible to arrange the conductive mass 122 'housed therein.

On the other hand, the conductive mass (122 ') may be formed through at least one through-hole so as to increase the contact area with the raw water. For example, the conductive mass 122 ′ may be in the form of a hollow tube or a porous form in which a plurality of through holes are formed. As a result, even if the conductive mass 122 'is formed in the same size, it is possible to further increase the contact area with the raw water as compared with the conductive mass without the through hole, thereby reducing the total number of the conductive mass 122' used. In addition, equivalent processing efficiency can be obtained.

On the other hand, the receiving member 123 may be made of an insulator or a non-conductor to prevent electrical short with the power electrode 121 'when the power is applied. For example, the receiving member 123 may be made of a material such as plastic, concrete, plywood, and the like, but the present invention is not limited thereto, and any known insulator or insulator may be used. In addition, the outer surface of the receiving member 123 is coated with a coating layer having at least one property of chemical resistance, corrosion resistance, and electrothermal resistance to damage the receiving member 123 by heavy metals contained in raw water. It can also be prevented.

In addition, the interval between the conductive mass 122 ′ and the power electrode 121 ′ filled in the receiving member 123 may have an appropriate interval so that smooth power may be applied while preventing electrical short. For example, the distance between the conductive plate 122 ′ and any one electrode plate of the power electrode 121 ′ may be 1 to 10 mm, and a portion of the receiving member 123 in which the second through hole 123 a is formed. The thickness of may be 1 ~ 10mm.

In addition, the number of the plurality of conductive masses 122 ′ filled in the receiving member 123 may be properly changed according to the processing capacity of the raw water to be treated. In addition, it should be noted that the amount of current applied to the power electrode 121 'may be appropriately changed according to the correlation with the total surface area of the conductive mass 122' filled in the receiving member 123 and contacting the raw water. . In addition, the number of electrode plates serving as the power electrode 121 ′ may be provided in plural, and the arrangement position may also be appropriately changed.

On the other hand, the electrocoagulation module 100 ′ according to the present invention has a diffuser 150 for generating a microbubble on the side of the first chamber 111 into which raw water flows, as shown in FIGS. 6 and 7. Can be.

That is, the diffuser 150 is disposed on the side of the first chamber 111 formed at the lower side of the second chamber 112 so that the fine bubble generated in the process of ejecting air supplied from the outside is the second bubble. It is possible to pass between the electrode plate of each of the electrode unit 120 disposed on the chamber 112 side.

Through this, aggregates such as a polymer hydroxide complex (flocs) generated during the electrocoagulation reaction are stuck to the electrode unit 120 to prevent the contamination of each of them, so that a smooth aggregation reaction can occur, and the By extending the service time, maintenance costs can be reduced.

To this end, the diffuser 150 may be a hollow tube having a predetermined length and a plurality of discharge holes 151 formed therethrough in the longitudinal direction (see FIG. 9), and the diffuser 150 may be formed in the first chamber. It may be arranged in a direction parallel to the inlet pipe 130 disposed in the (111).

Here, the diffuser 150 may be disposed at the same height as the inlet pipe 130, it may be placed on the upper or lower side of the inlet pipe 130.

At this time, the diffuser 150 may include a porous substrate 152 covering the discharge hole 151 so that the fine bubble discharged through the discharge hole 151 has a size of 10 ㎛ or less (Fig. 9). Reference), The porous substrate 152 may be formed with fine pores having an average pore size of 5㎛ or less.

When the size of the microbubble discharged through the discharge hole 151 exceeds 10 μm, it prevents the activation of the metal ions generated in the electrode unit 120 for the electric coagulation reaction when the power is applied, thereby smoothly generating ions. This is because it lowers.

Therefore, in the present invention, by covering the discharge hole 151 through which the bubble is discharged through the porous substrate 152 having the micropores, the microbubbles of 10 μm or less are generated to smoothly generate metal ions in the electrode unit 120. To be able.

Here, the porous substrate 152 may be provided to cover the entire outer surface of the diffuser 150, or may be provided only partially in the region corresponding to the discharge hole 151.

On the other hand, the electric coagulation module (100, 100 ', 200, 200') according to the present invention is a control unit for controlling the overall operation, such as the supply and interruption of power, the size of the power applied to the pair of power electrodes (121, 121 '), current density, etc. 140 may be included.

In this case, the controller 140 may periodically convert the polarity of the power applied to the pair of power electrodes 121 and 121 ′. Through this, the polarity applied to both surfaces of the power electrodes 121 and 121 'is periodically changed during the electrocoagulation reaction so that both surfaces can be used evenly. Accordingly, since both surfaces of the power electrode 121 can be used evenly, the replacement cycle of the power electrode 121 can be increased.

The electric coagulation water, which is the raw water passing through the above-described electrocoagulation module 3210, 100, 100 ′, 200, 200 ′, enters the filter module 3220, and filters various suspended substances including aggregates that are electroaggregated through the filter module 3220. Can lose.

To this end, the filter module 3220 may include a plurality of flat plate filter units 2000 having a filter medium 1000, as shown in FIGS. 14A and 14B. In this case, the plurality of flat plate filter units 2000 may form a unit block fixed to the outer case at predetermined intervals, and the filter module 3220 may be implemented by including at least one unit block.

The flat plate filter unit 2000 further includes a support frame 1100 for supporting the edge of the filter medium 1000, and in one region of the support frame 1100, the outside and the inside of the filter medium 1000. Inlet 1110 may be provided to gradient the pressure difference between the liver. In addition, the support frame 1100 may be formed with a flow path E for allowing the filtrate filtered through the filter media 1100 to flow out.

Specifically, when the filter unit 2000 applies a high pressure suction force through the suction port 1110, the electric coagulation water P including the electroaggregated aggregates disposed outside the filter medium 1000 as shown in FIG. 14B is filtered. The filtrate (Q ₁ ), which is directed toward the inside of the filter medium (1000) and passes through the filter medium (1000), flows along a flow path formed in the filter medium (1000) and is provided in the support frame (1100). Inflow to E), the introduced filtrate (Q ₂ ) may be discharged to the outside through the suction port 1110.

The flat filter unit 2000 is provided with a filter medium 1000 that can filter the electro-aggregated aggregates and other foreign matter. The filter media 1000 may be used without limitation in the case of a known filter media used in the water treatment field. However, it is important to select a filter medium having a high water treatment speed in consideration of the treatment capacity of 1 m ³ / h or more of the electrocoagulation module 3210 described above. If the filtration rate of the raw water flowing in a large amount and a high speed in the electrocoagulation module having a processing capacity of 1m ³ / h or more is slow, high filter back pressure is applied to the filter module 3220, resulting in increased filtration efficiency and durability of the device. There may be a problem, and if you increase the treatment speed of the raw water passing through the filter medium to prevent this, there is a problem that the filtration efficiency of the electro-aggregated foreign matter contained in the raw water may be reduced.

Accordingly, the filter medium 1000 provided in the filter module 3220 may have a filtration flow rate of 50 lmH or more with respect to the aggregates included in the introduced condensed water, thereby minimizing the increase in back pressure applied to the filtration unit, and simultaneously Raw water can be quickly supplied to the osmosis filtration unit 3300 in accordance with the processing capacity of the coagulation module 3210, and there is an advantage in that the coagulated foreign matter contained in the raw water introduced from the electrocoagulation module 3210 can be effectively removed. In addition, the filter module includes a plurality of filter units including the filter medium 1000, and the filter medium 1000 has a filtration flow rate of 50 LMH or more with respect to the electric coagulation water introduced from the electrocoagulation module 3210. As the filtration efficiency of the aggregate having a particle size of 0.2 μm or more is 99% or more, the introduced electrocoagulated water can be treated quickly, and the filtration efficiency of the aggregate is excellent.

In the case of the filter medium 1000 having the above-described physical properties, the filter module 3220 of the pretreatment unit 3200 included in the present invention may be used without limitation, but in terms of improved backwashing efficiency and durability due to high mechanical strength. As shown in FIG. 15, the filter medium 1000 according to an embodiment of the present invention includes the second supports 321 and 322 and the nanofiber webs 311 and 312 sequentially stacked on both surfaces of the first support 330. And filtrates filtered by the nanofiber webs 311 and 312 may be media having a filtration path flowing in the direction of the first support 130.

The filter media 1000 provided in the filter module according to an embodiment of the present invention has at least five layers as shown in FIG. 15, and includes two kinds of supports 321/322 and 330 having different thicknesses. In this case, the filter media 1000 is more preferably the basis weight of the nanofiber web (311,312) is 30g / ㎡ or less, the basis weight of the first support 330 is 250g / ㎡ or more, the thickness of the filter media (1000) may be at least 90% of the total thickness. Before describing each layer constituting the filter medium 1000 according to the present invention, the thickness of the first support 330 should be thick so that it is 90% or more of the total thickness of the filter medium 1000 and the filter medium 1000. The reason why the second support should be provided in addition to the first support will be described first.

As the water treatment process of the electrocoagulated water is repeated using the filter medium, foreign substances such as aggregates contained in the coagulated water stick to the filter medium to form an adhesive layer or to be embedded in the filter medium to block the flow path and reduce the filtration function. Whenever the same problem occurs, if the filter medium is replaced, the cost of seawater desalination increases. Accordingly, in order to prolong the use period of the filter medium, it is necessary to periodically perform a washing process to apply a physical stimulus to the filter medium to remove the foreign matter stuck to the filter medium or stuck in the filter medium, which is called backwashing. In general, backwashing removes foreign matter adhered to or stuck to the filter medium by strongly flowing or blowing air in a direction opposite to the filtration direction of the filter medium, and supplies the washing water and / or air to the filter medium and at the same time. It is necessary to supply the washing water or air at a pressure higher than the pressure applied to the filter medium in the filtration process.

Accordingly, in order for the filter medium to retain its backwashing ability, it is important to have a mechanical strength such that the filter medium is not deformed or damaged even at a high pressure applied, and a support for supplementing the mechanical strength is usually provided in the filter medium. . Factors that may affect the mechanical strength of the support may be the structure of the support, for example, the diameter of the fibers forming the nonwoven fabric when the support is a nonwoven fabric, fiber length, interfiber bonding, thickness, basis weight, the thickness is The thicker or the basis weight, the higher the mechanical strength of the support. Therefore, as an example for designing a filter medium resistant to backwashing, a thick nonwoven fabric may be used or a nonwoven fabric having a large basis weight may be used as a support even if the thickness is slightly thinner.

On the other hand, the support may have a large pore size so as not to affect the flow of the filtrate of the filter medium. The flow rate decrease due to the support provided to compensate for the mechanical strength is very undesirable as it lowers the main physical properties of the filter medium. For example, when using a nonwoven fabric having sufficient mechanical strength even at a thin thickness as a support, the basis weight of the nonwoven fabric is very large, so that the diameter and porosity of the pores in the nonwoven fabric are remarkably small, affecting the filtrate flow of the filter medium. Therefore, there is a problem that can not secure the desired level of flow rate.

Accordingly, in order to secure the mechanical strength of the filter medium 1000 while securing a sufficient flow path, the filter medium 1000 according to the present invention has a basis weight of 30 g / m 2 or less of the nanofiber webs 311 and 312 and the filter medium 1000 as a whole. It is preferred to have a first support 330 having a thickness of at least 90% of the thickness. In the filter media 1000 having a nanofiber web having a basis weight of 30 g / m 2 or less, the thickness of the first support 330 may occupy 90% or more of the total thickness of the filter media 1000, and more preferably, the filter media (1000) 95% or more of the total thickness, even more preferably 95 to 98%. If the first support is less than 90% of the total thickness of the filter media 1000, the filter media 1000 having a nanofiber web having a basis weight of 30 g / m 2 or less does not have sufficient mechanical strength and thus is difficult to perform backwashing. The replacement cycle of 1000 may be shortened. However, even when the thickness of the first support is less than 90% of the total thickness of the filter medium 1000, when the basis weight of the first support is small, there is a problem of not having sufficient mechanical strength. Thus, the basis weight of the first support may satisfy 250g / m 2 or more. If the basis weight of the first support is less than 250 g / m 2, mechanical strength for backwashing may not be developed, and thus damage to the media and its durability may be reduced. Adhesion can also be significantly reduced.

In addition, the first support having less than 90% of the total thickness of the filter media 1000 and having a mechanical strength sufficient to withstand backwashing may prevent the flow of electric coagulated water due to the first support, and a decrease in flow rate may occur. In this case, due to the high filtration rate of the filter medium (1000) for the raw water flowing in a high speed and / or a large amount in the electro-aggregation module of the treatment capacity of more than 1m ³ / h high in the filter module 3220 Back pressure is applied, which may cause problems in filtration efficiency and durability of the device. Preferably, the first support 330 may have a basis weight of 800 g / m 2 or less, and if the basis weight of the first support 330 exceeds 800 g / m 2, the mechanical strength may be less than 90% of the total thickness of the filter. Even if it is possible to secure the flow rate, there is a fear of a significant decrease in the flow rate.

However, when the bonding strength between the nanofiber webs 311 and 312 and the first support 330 which functions as the filter medium is weak, the durability of the filter medium 1000 due to backwashing may be lowered even though the mechanical strength is excellent. That is, the high pressure applied during the backwashing process may accelerate the interfacial separation between the layers forming the filter medium 1000, and in this case, as shown in FIG. 17, the filling of the separator may occur in the backwashing process. And there is a problem that the function can be significantly reduced or completely lost as a separator.

Therefore, having a certain level of adhesion between the first support having a significant increase in thickness and the nanofiber web as the media is very effective in implementing a filter medium that exhibits high pressure applied during backwashing and sufficient durability in frequent backwashing. It has an important meaning.

Typically, the method of attaching the support and the nanofiber web may be bonded to each other by using a separate adhesive material or by fusion of the low melting point component provided on the support to the nanofiber web. However, when the two layers are joined through separate bonding materials, the bonding materials may be dissolved by the water to be treated, and thus, the contamination of the filtrate and the water permeability may be reduced. If backwashing the filter media in which the bonding material is partially dissolved, the filter media may be hung or the nanofiber web may be peeled off and the filter media may be completely lost.

Accordingly, preferably, a method in which the nanofiber web and the support are bonded through the fusion (A) may be adopted, and heat and / or may be provided at both the support 1 and the nanofiber web 2 laminated as shown in FIG. 18. Pressure can be applied to join them. However, when joining them by applying heat and / or pressure, consideration should be given to minimizing physical and chemical deformation of the nanofiber web 2 functioning as a media due to the heat and pressure applied. When the nanoweb is physically and chemically modified, there is a problem that physical properties such as the flow rate, filtration rate, and the like of the filter media designed in the beginning may be changed.

On the other hand, the point that should be considered when selecting the heat and / or pressure conditions in the attachment process so that there is no physical / chemical deformation of the nanofiber web 2, the nanofiber web, the material properties of the support, for example melting point, thermal conductivity, heat capacity, etc. Can be. Typically, the low melting point component of the support may be fused to the nanofiber web by simultaneously applying a temperature above the melting point or a temperature and a pressure higher than the melting point, or the low melting point component of the support may be fused to the nanofiber web by applying a high pressure even if the melting point is slightly lower than the melting point. .

However, the material for forming the support or the nanofiber web is a polymer compound, and since the polymer compound has a low thermal conductivity and a very large heat capacity, even if a predetermined heat (H ₁ , H ₂ ) is applied to both sides as shown in FIG. In order for (H ₁ , H ₂ ) to reach the interface between the nanofiber web 1 and the support 2 and to raise the temperature of the low melting point component of the support 2 to the melting point, heat is continuously applied for a long time. Should be added. Furthermore, when the thickness of the support 1 is very thick as shown in FIG. 18, the heat (H ₂ ) transmitted from the lower side is transferred to the vicinity of the interface between the nanofiber web 2 and the support 1 and is provided at the support nearby. It may take longer to raise the temperature of the melting point component to the melting point, and it is necessary to apply more heat from below to shorten the time. However, when too much heat is applied downward, there is a problem that melting of the low melting point component first occurs under the first support, and the shape and structure of the support may be changed.

Another method can solve the difficulty of the thickness of the support (1) by increasing the heat (H1) applied from the upper side, in this case, the physical / chemical deformation of the nanofiber web (2) can be caused, There is a problem that may not fully express the physical properties of the filter medium designed in.

In addition, when the thickness of the support 1 is very thick, the diameter of the fibers constituting the support 1 may be very large, which causes a small area of contact between the support 1 and the nanofiber web 2 when laminated. The adhesion is inevitably lowered, which is very likely to be easily peeled off during the backwash or swelling of the nanofiber web (2).

Accordingly, the filter medium 1000 according to an embodiment of the present invention does not directly face the first support 330 and the nanofiber webs 311 and 312, and interposes the second supporters 321 and 322 that are thinner. In this way, the interlayer adhesion process can be performed more stably and easily, expressing a remarkably excellent bonding force at the interface between each layer, and can minimize the problem of separation and separation even if high external force is applied due to backwashing.

Referring to FIG. 19A, the second support 3, which occupies less than 10% of the total thickness of the filter medium, has a thickness difference from the nanofiber web 2 and the first support 1. As the thickness becomes significantly smaller than the difference between the thicknesses, the heat (H ₁ , H ₂ ) applied from above and below the laminate of the nanofiber webs 2 and the second support 3 reaches the interface between them, It is easier to form B) than in FIG. 3. In addition, it is easier to control the amount and time of heat applied than in FIG. 18, which is advantageous in preventing physical / chemical deformation of the nanofiber web 2, so that the nanofiber web 2 is supported on the second support 3 as shown in FIG. 18A. ) Is combined, there is an advantage that can be bonded to the nanofibers with excellent adhesion on the support without changing the physical properties of the initially designed nanofiber web (2).

On the other hand, in order for the second support 321 and 322 to simultaneously express excellent adhesion with the first support 330 and the nanofiber webs 311 and 312, the basis weight of the second support 321 and 322 is preferably the nanofiber webs 311 and 312. 1.5 to 6 times the basis weight of the, the basis weight 330 of the first support may be 8 to 16.5 times the basis weight of the second support (321,322). If the basis weight of the second support is provided such that any one of the basis weights of each of the first support / nano fiber does not satisfy the above range, there is a high possibility of peeling off during backwashing due to the decrease in adhesion force, and the backwashing efficiency may be lowered. And / or the flow rate can be significantly reduced.

Referring to each configuration of the filter medium 1000 described above, the first support 330 supports the filter medium 1000 and forms a large flow path to perform a filtration process or a backwashing process more smoothly. In charge of. Specifically, when the pressure gradient is formed such that the pressure inside the filter media is lower than the outside of the filter media in the filtration process, the filter media may be compressed. In this case, as the flow path through which the filtrate flows inside the filter media is significantly reduced or blocked, There is a problem that a greater differential pressure is applied to the filter medium and at the same time the flow rate is significantly lowered. In addition, in the backwashing process, an external force may be applied to expand in both directions from the inside of the filter medium, and when the mechanical strength is low, the filter medium may be damaged due to the external force applied.

The first support 330 is provided to prevent the above problems occurring in the filtration process and / or backwashing process, may be a known porous member that is used in the water treatment field, the mechanical strength is secured, for example The first support may be a nonwoven, woven or fabric.

The fabric means that the fibers included in the fabric has a longitudinal direction, the specific structure may be plain weave, twill weave, etc., the density of the warp and weft is not particularly limited. In addition, the knitted fabric may be a known knit structure, a knitted fabric, a warp knitted fabric, or the like, and may be, for example, a tricot (Tricot) in which yarn is knitted. In addition, as shown in FIG. 15, the first support 330 may be a non-woven fabric having no longitudinal or lateral direction in the fiber 330a, and may be a dry nonwoven fabric such as a chemical bonding nonwoven fabric, a thermal bonding nonwoven fabric, an airlay nonwoven fabric, a wet nonwoven fabric, or a spanless nonwoven fabric. Known nonwovens can be used which are produced by various methods such as needle punching nonwovens or meltblown.

The first support 330 may be provided to occupy 90% or more of the total thickness of the filter medium as described above in order to express a sufficient mechanical strength. For example, the first support 130 may be 2 to 8 mm, more preferably 2 to 5 mm, even more preferably 3 to 5 mm. If the thickness is less than 2 mm, it may not develop sufficient mechanical strength to withstand frequent backwashing. In addition, when the thickness exceeds 8mm, when the filter medium is implemented as a filter unit to be described later, when implementing a plurality of filter units as a filter module of a limited space, the degree of integration of the filter medium per unit volume of the module can be reduced.

 Preferably, the first support 330 may satisfy the thickness conditions as described above, and the basis weight may be 250 to 800 g / m 2, and more preferably 350 to 600 g / m 2. If the basis weight is 250g / ㎡ it may be difficult to express sufficient mechanical strength, there is a problem that the adhesion to the second support is reduced, if the basis weight exceeds 800g / ㎡ it does not form a sufficient flow path to reduce the flow rate And, there may be a problem that smooth backwashing due to the increased differential pressure is difficult.

In addition, when the first support 330 is formed of a fiber, such as a nonwoven fabric, the average diameter of the fiber may be 5 ~ 50㎛, more preferably 20 ~ 50㎛, even more preferably 25 ~ 40 μm, and through this, when considering the diameters of the fibers constituting the second support bodies 121 and 122 to be described later, an increase in abutment area when the first support body and the second support body are laminated and an increased adhesion force may be expressed therethrough. There is an advantage to this. For example, the diameter of the fiber may be 35 μm. In addition, the first support 330 may have an average pore diameter of 20 to 200 μm, preferably 30 to 180 μm. For example, the first support 330 may have an average pore diameter of 100 μm, and porosity. May be 50 to 90%, preferably 55 to 85%. For example, the first support 330 may have a porosity of 70%, but is not limited thereto. In the filtration process and / or the backwash process, The nanofiber webs 311 and 312 described below are not limited as long as their porosity and pore size are sufficient to express a desired level of mechanical strength and to smoothly form a flow path even at high pressure.

When the first support 330 is a material used as a filter media support, there is no limitation in the material. As a non-limiting example, synthetic polymer components selected from the group consisting of polyesters, polyurethanes, polyolefins and polyamides; Alternatively, a natural polymer component including cellulose may be used. However, when the first support body has strong brittle physical properties, it may be difficult to expect a desired level of bonding force in the process of laminating the first support body and the second support body. However, the surface may have a macroscopic uneven shape while forming porosity, and a surface formed of fibers such as a nonwoven fabric may not have a smooth surface depending on the arrangement of the fibers, the fineness of the fibers, and the degree may vary depending on the location. to be. If the remaining parts are joined while there is a part that is not in close contact at the interface between the two layers to be laminated, the part that is not in contact may start the interlayer separation. In order to solve this problem, it is necessary to carry out the lamination process by applying pressure from both layers to increase the degree of adhesion between the two layers. There is a limit to increase, the support may be damaged when a greater pressure is applied, the material of the first support is good flexibility, high elongation may be suitable, preferably have a good adhesion with the second support (321,322) The first support 330 may be made of a polyolefin material.

Meanwhile, the first support 330 may include a low melting point component in order to bind with the second supports 321 and 322 without a separate adhesive or an adhesive layer. When the first support 330 is a fabric such as a nonwoven fabric, the first support 330 may be made of a first composite fiber 330a including a low melting point component. The first composite fiber 330a may include a support component and a low melting point component such that at least a portion of the low melting point component is exposed to an outer surface. For example, a sheath-core composite fiber in which a support component forms a core portion and a low melting component forms a sheath portion surrounding the core portion, or a side-by-side composite fiber in which a low melting component is disposed on one side of the support component. Can be. As described above, the low melting point component and the support component may be preferably polyolefin-based in terms of flexibility and elongation of the support, and for example, the support component may be polypropylene and the low melting component may be polyethylene. Melting point of the low melting point component may be 60 ~ 180 ℃, more preferably 100 ~ 140 ℃, through which the nanofiber web, the adhesive strength can be expressed with excellent strength without damaging the second support, etc. It is advantageous to achieve.

Next, the second supports 321 and 322 disposed on both surfaces of the first support 330 described above will be described. The second supports 321 and 322 support the nanofiber webs 311 and 312 described below, and serve to increase the bonding force of each layer provided in the filter medium.

The second supports 321 and 322 are not particularly limited as long as they generally serve as a support for the filter media. However, the second supports 321 and 322 may be preferably woven, knitted or nonwoven. The fabric means that the fibers included in the fabric has a longitudinal direction, the specific structure may be plain weave, twill weave, etc., the density of the warp and weft is not particularly limited. In addition, the knitted fabric may be a known knit structure, but may be a knitted fabric, a warp knitted fabric, and the like, but is not particularly limited thereto. In addition, the non-woven fabric means that the fibers included in the longitudinal direction does not have a known, such as chemical bonding non-woven fabrics, thermal bonding non-woven fabrics, such as dry non-woven fabrics such as wet non-woven fabrics, wet non-woven fabrics, span non-woven fabrics, needle punched non-woven fabrics or melt blown It is possible to use a nonwoven fabric produced by the conventional method.

For example, the second support 323 and 322 may be a nonwoven fabric, wherein the fibers forming the second support 321 and 322 may have an average diameter of 5 to 30 μm, more preferably 10 to 25 μm. Considering the diameters of the fibers constituting the first support 130 and the diameters of the fibers constituting the nanofiber webs 311 and 312 together, the area abutting when the first support and the second support are laminated and the second support and When the nanofiber web is laminated, there is an advantage of expressing an increased adhesion and an increased adhesion area therethrough. In addition, the thickness of the second support 321, 322 may be 100 ~ 400㎛, more preferably 150 ~ 400㎛, even more preferably 150 ~ 250㎛, for example 200㎛ Can be. If the thickness of the second support is less than 100 μm, it may be difficult to ensure sufficient mechanical strength during backwashing, and in particular, there is a fear that the adhesion between the first support and / or the nanofiber web is reduced. Or the basis weight is too large, the water permeability is lowered, there is a fear that peeling occurs during backwash. In addition, if the thickness exceeds 400㎛ thermal bonding may not be easy when laminating with the nanofiber web, which may cause the peeling during backwashing.

In addition, the second supports 321 and 322 may have an average pore diameter of 20 to 100 μm, and porosity may be 50 to 90%. However, the present invention is not limited thereto, and supports the nanofiber webs 311 and 322 to be described later to express a desired level of mechanical strength, and does not inhibit the flow of the filtrate flowing through the nanofiber webs 311 and 322. The porosity and the pore size are not limited.

In addition, the basis weight of the second support (321,322) may be 35 ~ 100g / ㎡, more preferably 35 ~ 75g / ㎡, for example, may be 40 g / ㎡. If the basis weight is less than 35g / m 2, the amount of fibers forming the second support distributed at the interface formed with the nanofiber webs 311 and 312 to be described later may be small, thus effectively bonding the second support to contact the nanofiber web. Reduction of the area may not be able to express the desired level of binding force. In addition, there may be a problem that may not develop sufficient mechanical strength to support the nanofiber web, the adhesion with the first support is reduced. In addition, if the basis weight exceeds 100g / ㎡ it may be difficult to secure the desired flow rate, there may be a problem that smooth backwashing is difficult due to the increased differential pressure.

If the second support (321,322) is a material used as a support for the filter medium is not limited in the material. As a non-limiting example, synthetic polymer components selected from the group consisting of polyesters, polyurethanes, polyolefins and polyamides; Alternatively, a natural polymer component including cellulose may be used.

However, the second supports 321 and 322 may be polyolefin-based polymer components to improve adhesion between the nanofiber webs 311 and 312 and the first support 130 described later. In addition, when the second support (321,322) is a fabric such as a non-woven fabric may be made of a second composite fiber (321a) containing a low melting point component. The second composite fiber 321a may include a support component and a low melting point component such that at least a portion of the low melting point component is exposed to the outer surface. For example, a sheath-core composite fiber in which a support component forms a core portion and a low melting component forms a sheath portion surrounding the core portion, or a side-by-side composite fiber in which a low melting component is disposed on one side of the support component. Can be. As described above, the low melting point component and the support component may be preferably polyolefin-based in terms of flexibility and elongation of the support, and for example, the support component may be polypropylene and the low melting component may be polyethylene. Melting point of the low melting point component may be 60 ~ 180 ℃, more preferably 100 ~ 140 ℃, it is advantageous to achieve the object of the present invention, such that it can express the adhesion with excellent strength without damaging the nanofiber web through this. .

If the first support 330 described above is implemented with a first composite fiber 330a including a low melting point component to express more improved bonding force with the second support 321,322, the first support 330 and the first support 330 At the interface between the two supports 321, a more firm fusion may be formed due to the fusion of the low melting point component of the first composite fiber 330a and the low melting point component of the second composite fiber 321a. In this case, the first composite fiber 330a and the second composite fiber 321a may be the same material in terms of compatibility.

Next, the nanofiber webs 311 and 312 disposed above the second supports 321 and 322 will be described. The nanofiber webs 311 and 312 may be a three-dimensional network structure formed by randomly stacking one or several strands of nanofibers in three dimensions (see FIG. 16).

The nanofibers forming the nanofiber web may be formed of a known fiber forming component. However, preferably, in order to express excellent chemical resistance and heat resistance, a fluorine-based compound may be included as a fiber-forming component, thereby ensuring filtration efficiency / flow rate to a desired level without changing the physical properties of the filter medium even if raw water is seawater, and using it for a long time. There is an advantage to have a cycle. The fluorine-based compound may be used without limitation in the case of a known fluorine-based compound that can be made of nanofibers, for example, polytetrafluoroethylene (PTFE) -based, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymerization system, Tetrafluoroethylene-hexafluoropropylene copolymerization system, tetrafluoroethylene-hexafluoropropylene-perfluoroalkyl vinyl ether copolymerization system, ethylene-tetrafluoroethylene copolymer (ETFE) system, polychlorotrifluoroethylene (PCTFE) -based, ethylene-chlorotrifluoroethylene copolymer (ECTFE) -based and polyvinylidene fluoride (PVDF) may include any one or more compounds selected from the group, more preferably low production cost It is easy to mass-produce nanofibers through electrospinning and has excellent mechanical strength and chemical resistance. Polyvinyl may be a fluoride (PVDF). In this case, when the nanofibers include PVDF as a fiber forming component, the weight average molecular weight of the PVDF may be 10,000 to 1,000,000, preferably 300,000 to 600,000, but is not limited thereto.

In addition, the nanofibers may have an average diameter of 0.05 to 1 μm, more preferably 50 to 450 nm, for example, 250 nm. If the average diameter of the nanofibers is less than 50nm, the porosity and permeability may be lowered. If the average diameter exceeds 1㎛, the filtration efficiency may be lowered and the tensile strength may be lowered. In addition, the nanofibers may have an aspect ratio of 1,000 to 100,000, but is not limited thereto. For example, the nanofibers provided in the nanofiber webs 311 and 312 include a first nanofiber group having a diameter of 0.1 to 0.2 μm, a second nanofiber group having a diameter of 0.2 to 0.3 μm and a diameter of 0.3 to 0.4 μm. 3 nano-fiber group may include 25 to 45% by weight, 40 to 60% by weight, 5 to 15% by weight relative to the total weight of the nanofiber web 311, thereby improving adhesion to the second support, It is possible to further improve the mechanical strength due to backwashing by increasing its mechanical strength and the like, and may be more advantageous to achieve the object of the present invention, such as obtaining filtration efficiency and excellent flow rate. For example, the first nanofiber group having a diameter of 0.1 to 0.2 μm, the second nanofiber group having a diameter of 0.2 to 0.3 μm, and the third nanofiber group having a diameter of 0.3 to 0.4 μm are respectively 35 wt%, 53 wt%, It may include 12% by weight.

The nanofiber webs 311 and 312 may be formed to have a thickness of 0.5 to 200 μm, more preferably 10 to 50 μm, and for example, 20 μm. If the thickness is less than 0.5㎛, it is difficult to withstand backwashing due to the decrease in mechanical strength, so the risk of damage is very large, or the pore diameter is very small, there is a fear that the flow rate is significantly reduced. In addition, if the thickness exceeds 200㎛, there is a fear that swelling or peeling due to the flow rate decrease, backwashing. The porosity of the nanofiber webs 311 and 312 may be 40 to 90%, more preferably 60 to 90%. In addition, the average pore diameter may be 0.1 to 5㎛, more preferably 0.1 to 3㎛, for example, may be 0.25㎛. If the average pore diameter of the nanofiber web is less than 0.1 μm, the water permeability to the filtrate may be reduced, and if the average pore diameter is more than 5 μm, the filtration efficiency for contaminants may not be good.

In addition, the nanofiber webs 311 and 312 may be provided in the filter medium 1000 more than one layer, wherein the porosity, pore size, basis weight and / or thickness of each nanofiber web may be different.

Meanwhile, the nanofibers forming the nanofiber webs 311 and 312 may be modified to increase hydrophilicity. For example, a hydrophilic coating layer may be further provided on at least part of an outer surface of the nanofibers. If the nanofibers contain a fluorine-based compound as described above, the fluorine-based compound is very hydrophobic, so that the flow rate is poor when the filtrate is a hydrophilic solution. To this end, a hydrophilic coating layer may be further provided on the surface of the hydrophobic nanofiber, and the hydrophilic coating layer may be a known one, and for example, may be formed including a hydrophilic polymer having a hydroxy group or the hydrophilic polymer is crosslinked through a crosslinking agent. Can be formed. For example, the hydrophilic polymer may be a single or mixed form of polyvinyl alcohol (PVA), ethylene vinyl alcohol (Ethylenevinyl alcohol, EVOH), sodium alginate (Sodium alginate), and most preferably polyvinyl alcohol (PVA). In addition, the crosslinking agent may be used without limitation in the case of a known crosslinking agent having a functional group capable of crosslinking through a hydroxy group and a condensation reaction of the hydrophilic polymer. For example, the functional group may be a hydroxyl group, a carboxyl group, or the like.

On the other hand, the hydrophilic coating layer may be formed on some or all of the outer surface of the nanofiber. In this case, the hydrophilic coating layer may be coated with nanofibers so that 0.1 ~ 2g per nanofiber web unit area (㎡).

The wetting angle of the surface of the nanofiber webs 311 and 312 modified to have a hydrophilic coating layer may be 30 ° or less, more preferably 20 ° or less, even more preferably 12 ° or less, even more preferably 5 ° or less. And, through this there is an advantage to ensure an improved flow rate despite the fiber web implemented with hydrophobic nanofibers in the material.

The filter medium 1000 may be manufactured by the manufacturing method described below, but is not limited thereto.

The filter medium 1000 comprises the steps of: (1) laminating the nanofiber web and the second support; And (2) disposing the laminated nanofiber web and the second support on both sides of the first support such that the second support contacts the first support.

First, as step (1), the step of laminating the nanofiber web and the second support may be performed.

The nanofiber web may be used without limitation in the case of a method of forming a fibrous web having a three-dimensional network shape by providing a nanofiber. Preferably, the nanofiber web may form a nanofiber web by electrospinning a spinning solution containing a fluorine-based compound on the second support.

The spinning solution may include, for example, a fluorine-based compound and a solvent as a fiber forming component. The fluorine-based compound is preferably contained in 5 to 30% by weight, preferably 8 to 20% by weight in the spinning solution, if less than 5% by weight of the fluorine-based compound is difficult to form a fiber, the spinning state is not spun into fibrous droplets Even when the film is sprayed to form a film or spinning, beads are formed a lot and the volatilization of the solvent is not made well, so that pores may be blocked in a calendering process described later. In addition, if the fluorine-based compound exceeds 30% by weight, the viscosity rises and solidification occurs on the surface of the solution, making it difficult to spin for a long time, and the fiber diameter may increase, making it impossible to form a fibrous size of micrometer or less.

The solvent may be used without limitation in the case of a solvent which does not generate a precipitate while dissolving a fluorine-based compound which is a fiber forming component and does not affect the radioactivity of the nanofibers described later, but is preferably γ-butyrolactone, cyclohexanone, 3 It may include any one or more selected from the group consisting of -hexanone, 3-heptanone, 3-octanone, N-methylpyrrolidone, dimethylacetamide, acetone dimethyl sulfoxide, dimethylformamide. For example, the solvent may be a mixed solvent of dimethylacetamide and acetone.

The prepared spinning solution may be prepared nanofibers through known electrospinning apparatus and method. For example, the electrospinning apparatus uses an electrospinning apparatus having a single spinning pack having one spinning nozzle, or a plurality of single spinning packs for mass production, or an electrospinning apparatus having a spinning pack having a plurality of nozzles. It is okay. In addition, in the electrospinning method, dry spinning or wet spinning having an external coagulation bath can be used, and there is no limitation in accordance with the method.

When the stirred spinning solution is added to the electrospinning apparatus, a nanofiber web formed of nanofibers may be obtained when electrospinning onto a collector, for example, paper. Specific conditions for the electrospinning is one example, the air spray nozzle provided in the nozzle of the spinning pack may be set to the air pressure of the air injection is 0.01 ~ 0.2MPa range. If the air pressure is less than 0.01MPa, it does not contribute to the collection and accumulation. If the air pressure exceeds 0.2MPa, the cone of the spinning nozzle is hardened to block the needle, which may cause radiation trouble. In addition, when spinning the spinning solution, the injection speed of the spinning solution per nozzle may be 10 ~ 30㎛ / min. In addition, the distance between the tip of the nozzle and the collector may be 10 ~ 30cm. However, the present invention is not limited thereto, and may be changed according to the purpose.

Alternatively, the nanofiber web can be directly formed on the second support by electrospinning the nanofibers directly on the second support. The nanofibers accumulated / collected on the second support have a three-dimensional network structure, and heat and / or pressure are applied to maintain porosity, pore size, basis weight, etc., which are suitable for expressing water permeability and filtration efficiency of a desired separator. In addition to the accumulated / collected nanofibers can be implemented as a nanofiber web having a three-dimensional network structure. A specific method of applying the heat and / or pressure may employ a known method, and by way of non-limiting example, a conventional calendaring process may be used and the temperature of the applied heat may be 70-190 ° C. In addition, when the calendering process is carried out, it may be divided into several times and carried out a plurality of times. For example, the pores after performing a drying process to remove some or all of the solvent and water remaining in the nanofibers through the first calendering. Secondary calendaring can be performed for adjustment and strength enhancement. At this time, the degree of heat and / or pressure applied in each calendaring process may be the same or different.

On the other hand, when the second support is implemented by a low melting point composite fiber, the binding through the heat-sealing of the nanofiber web and the second support may be simultaneously carried out through the calendering process.

In addition, a separate hot melt powder or hot melt web may be further interposed to bind the second support and the nanofiber web. At this time, the heat may be applied to 60 ~ 190 ℃, the pressure may be applied to 0.1 ~ 10kgf / ㎠, but is not limited thereto. However, components such as hot melt powder, which are added separately for binding, frequently generate fumes or melt in the lamination process between supports and supports and nanofibers to close pores, thus achieving the flow rate of the first designed filter media. You may not be able to. In addition, it is preferable to bind the second support and the nanofiber web without being included because it may dissolve during water treatment and cause environmentally negative problems.

Thereafter, heat treating the hydrophilic coating layer-forming composition treated on the nanofiber web to form a hydrophilic coating layer; can be performed. Through the heat treatment, the drying process of the solvent in the hydrophilic coating layer forming composition can be made at the same time. The heat treatment may be performed in a dryer, wherein the heat is applied may be a temperature of 80 ~ 160 ℃, the treatment time may be 1 minute to 60 minutes, but is not limited thereto.

Next, in step (2), the laminated nanofiber web and the second support are placed on both surfaces of the first support such that the second support contacts the first support in the laminated second support and the nanofiber web. Supporting step is performed.

Step (2) comprises the steps of 2-1) laminating the second support and the nanofiber web laminated in step (1) on both sides of the first support; And 2-1) fusing the first support and the second support by applying one or more of heat and pressure.

As a specific method of applying heat and / or pressure in step 2-2), a known method may be adopted, and by way of non-limiting example, a conventional calendaring process may be used, and the temperature of heat applied is 70 ˜190 ° C. In addition, when the calendaring process is performed, it may be divided into several times and may be performed a plurality of times. For example, the second calendaring may be performed after the first calendaring. At this time, the degree of heat and / or pressure applied in each calendaring process may be the same or different. Through the step 2-2), the second support and the first support may be bound by heat fusion between the second support and there is an advantage in that a separate adhesive or an adhesive layer may be omitted.

On the other hand, the filter module 3220 included in another embodiment of the present invention is a filter medium in order to achieve a further improved water treatment speed, as shown in FIG. 20, the nanofiber webs 411 and 412 are formed on both sides of the first support 430. The filter medium 1001 may be provided, wherein the first support 430 passes through a plurality of surfaces facing the nanofiber webs 411 and 412, respectively, in order to increase the flow path and minimize water permeation resistance. The hole Q may be provided. The hole Q provided in the first support 430 provides a larger flow path for the filtrate passing through the nanofiber webs 411 and 412, which greatly reduces the flow resistance of the filtered raw water and is applied to the inside of the filter medium. Pressure can also be lowered. Therefore, even if a greater filtration pressure and / or backwash pressure is applied to the filter media, the pressure applied to the filter media can be relatively reduced, and damage to the filter media including nanofiber webs is minimized and the shape is better maintained. It may be easy to remove the foreign condensed particles more quickly in accordance with the raw water flowing in the high speed and / or large capacity from the electrocoagulation module.

Alternatively, the first support 430 of the filter medium 1002 is the second support body as shown in FIG. 21 to express the mechanical strength and the backwashing efficiency of the filter medium 1000 as shown in FIG. It may be provided with a plurality of holes (Q) penetrating the surface opposite to (421,422).

In addition, as illustrated in FIGS. 22 and 23, the filter media 1003 and 1004 may include a plurality of first holes Q and a plurality of first holes Q that penetrate through surfaces facing the second supports 521 and 522. Further improved flow rate can be obtained through the provision of a plurality of second holes P passing through the second supports 521 and 522 in the same direction as the one hole Q is penetrated. In this case, the diameter p of the second hole P may be equal to or smaller than the diameter q of the first hole Q. In addition, the second hole P may be positioned to communicate with the first hole Q as illustrated in FIG. 22, or may be positioned so as not to communicate with the first hole Q as illustrated in FIG. 23. The flow rate, the bonding strength of the first support 530 and the second support (521, 522) may be appropriately changed.

In addition, the diameter of the above-mentioned holes P and Q, the shape of a cross section, the space | interval between holes, etc. can change and implement according to the objective, and it does not specifically limit in this invention.

Meanwhile, between the electrocoagulation module 3210, 100, 100 ′, 200 and the filter module 3220, the storage tank and the electrocoagulation water are temporarily stored in the coagulation water processed by the coagulation module 3210, 100, 100 ′, 200. A supply pump for supplying to the filter module 3220, and other control device may be further provided.

Next, the osmosis filtration unit 3300 for treating the pretreatment water introduced from the pretreatment unit 3200 will be described.

The osmosis filtration unit 3300 includes an osmosis membrane module for desalination of the introduced pretreatment water, and the osmosis membrane module may be a reverse osmosis membrane module or an forward osmosis membrane module. In addition, according to the osmosis method, if the osmosis membrane module is a reverse osmosis membrane module may be further provided with a high-pressure pump for applying a pressure higher than the osmotic pressure of the raw water or sea water.

The osmosis module may include a plurality of osmosis units in which unit units are formed in a known shape, including a known reverse osmosis membrane or forward osmosis membrane. Referring to FIGS. 24 and 25 as an example of the osmosis unit, the osmosis unit 700 includes a plurality of osmosis membranes 730 wound around a porous permeate outlet pipe 720 in a spiral wound form. Can be.

The porous permeate outlet tube 720 may be used without limitation in the case of an outlet tube that is typically used for a reverse osmosis membrane or an forward osmosis membrane. The porous permeate outflow pipe 720 includes a plurality of holes 721 through which the treated water from which salt is removed through the osmosis process can be discharged. Preferably, the diameter of the porous permeated water outlet tube 720 may be 4 inches to 8 inches. May be between 30 and 50 inches. However, the present invention is not limited thereto, and the diameter and length of the porous permeate outlet pipe 720 may vary depending on the purpose.

In addition, the osmosis membrane 730 may include a spacer 733 interposed between the first osmosis membrane 731, the second osmosis membrane 732, and the first and second osmosis membranes 731 and 732. The first osmosis membrane 731 and the second osmosis membrane 732 may be known reverse osmosis membranes or forward osmosis membranes, for example, a support, a polymer support formed on the support and a selective separation layer formed on the polymer support. Can be configured.

The support is responsible for the function of the support member of the membrane, there is no particular limitation as long as it serves as the support of the membrane, it may be preferably a woven or non-woven fabric. The fabric means that the fibers forming the fabric has a longitudinal direction, the specific structure may be plain weave, twill weave, etc., the density of the warp and weft is not particularly limited. The material of the support is preferably a synthetic fiber selected from the group consisting of polyester, polypropylene, nylon and polyethylene; Or natural fibers containing cellulose can be used. When the support is a nonwoven layer, physical properties of the membrane may be adjusted according to porosity and hydrophilicity of the material. When the support is a non-woven fabric, the average pore diameter may be 1 to 600 μm, and preferably 5 to 300 μm to increase the smooth inflow and water permeability of the fluid required for the reverse osmosis membrane. However, it is not limited to the diameter of the pores. When the non-woven fabric is used, the thickness is preferably 20 to 150 μm. In this case, if the thickness is less than 20 μm, the thickness and the area of the entire membrane are insufficient, and if the thickness exceeds 150 μm, the flow rate may be reduced.

Next, the polymer support formed on the support will be described. The polymer support is not particularly limited as long as it can form a reverse osmosis membrane, but in order to consider mechanical strength, it is preferable to use a weight average molecular weight in the range of 65,000 to 150,000, and a preferred example includes polysulfone or polyethersulfone. Single or mixed form of polysulfone polymer, polyamide polymer, polyimide polymer, polyester polymer, olefin polymer such as polypropylene, polybenzoimidazole polymer, polyvinylidene fluoride or polyacrylonitrile Can be. The polymer support may have a thickness of 30 to 300 μm, and if the thickness is less than 30 μm, there may be a problem of lowering the flow rate and durability due to consolidation. If the thickness exceeds 300 μm, there may be a problem of decreasing the flow rate due to the length of the flow path. Can be. In addition, the pore size of the polymer support is preferably 1 to 500 nm. If the pore size exceeds 500 nm, the thin film may be recessed into the pore diameter of the polymer support layer after formation of the thin film of the selective separation layer, making it difficult to achieve the desired flat sheet structure.

Next, the selective separation layer formed on one surface of the polymer support may be used without limitation as long as it is a selective separation layer that can be used for the reverse osmosis membrane, preferably, polyamide-based, polypiperazine-based, polyphenylene diamine-based, polychloro It may include any one or more selected from the group consisting of phenylene diamine-based, polybenzidine-based, and may be more preferably formed of a polyamide-based material. The selective separation layer may have a thickness of 0.1 to 1 μm. When the thickness of the selective separation layer is less than 0.1 μm, the salt removal ability may be degraded, and thus, the separation layer may not function as a separation layer. There may be a problem.

The osmosis membrane 730 may be provided in the osmosis unit 700 so that the selective separation layers of the first osmosis membrane 731 and the second osmosis membrane 732 face the outside, and each support body abuts each other. In order to secure a sufficient flow path, a spacer 733 may be provided between the first osmosis membrane 731 and the second osmosis membrane 732. The spacer 733 increases the generation of the flow path in the osmosis membrane 730 and the amount of the flow path to improve the inflow of raw water to be desalination, and to generate a uniform filtration flux along the flow path. In addition, as it promotes turbulence along the flow path, the flow rate at the surface of the osmosis membrane is improved, so that the osmotic action can be made more smoothly, so that a high amount of fresh water can be obtained. The spacer may be a mesh or a tricoat, preferably polypropylene, polyethylene, poly-4-methylpentene, crystalline copolymers with propylene-αolefin, polyethylene terephthalate, polybutylene terephthalate, polyamide and One or more resins selected from the group consisting of polycarbonate or may be formed of a modified polyester (LMP: Low Melting Polyethylene Terephthalate) copolymerized nylon or polypropylene to a polyethylene terephthalate resin. In addition, the thickness of the spacer may be 0.01 to 1 mm, but is not limited thereto.

The osmosis membrane 730 described above may be wound in a spiral wound around the porous permeate outlet pipe 720 in a plurality, and may include a spacer 740 to form a smooth flow path between the osmosis membranes 730. For example, it may be a mesh sheet.

The osmosis membrane 730 wound around the porous permeate outflow pipe 720 via the spacer may be provided in an outer housing 710 that can accommodate it therein and may be implemented as an osmosis unit 700. A plurality of units 700 may be mounted to form an osmotic module.

On the other hand, the osmosis unit described above is based on the osmosis membrane of the flat membrane, but the osmosis membrane may be a hollow fiber membrane, may be an osmosis unit implemented by a known reverse osmosis or forward osmosis hollow fiber membrane.

The treated water passing through the osmosis filtration unit 3300 including the osmosis module described above may be further subjected to a known post-treatment facility for sterilization and filtering of other target substances, and the filtered water after the post-treatment facility is stored in a storage tank and then drinking water. , Industrial water, agricultural water, and the like.

Although the present invention will be described in more detail with reference to the following examples, the following examples are not intended to limit the scope of the present invention, which will be construed as to aid the understanding of the present invention.

Example 1

As a pretreatment unit, an electrocoagulation module and a filter module were prepared. In the electrocoagulation module, as shown in FIGS. 13A and 13B, 300 conductive agglomerates of aluminum are disposed between the power electrodes facing each other, and the distance between the conductive material and one of the power electrodes is processed so that the maximum distance is 10 mm. An electrocoagulation module having a capacity of 1 m ³ / h was prepared. In addition, the filter module is implemented as a filter unit of the flat membrane as shown in Figure 14a and 14b prepared as shown in Figure 14, it was mounted to the filter module 20 implemented filter units. Thereafter, the electrocoagulated water treated by the electrocoagulation module was introduced into the filter module, and the filtrate treated by the filter module was connected to be introduced into the osmosis filtration unit. The osmosis filtration unit was equipped with a known reverse osmosis module and was configured according to a known design, thereby implementing a seawater desalination device as shown in Table 1 below.

* Preparation-Filter Media

First, in order to prepare a spinning solution, 12 g of polyvinylidene fluoride (Arkema, Kynar761) as a fiber forming component was mixed with 88 g of a mixed solvent in a weight ratio of dimethylacetamide and acetone at 70:30 at a temperature of 80 ° C. for 6 hours. While dissolving using a magnetic bar to prepare a mixed solution. The spinning solution was introduced into a solution tank of an electrospinning apparatus and discharged at a rate of 15 µl / min / hole. At this time, the temperature of the spinning section is 30 ℃, the humidity is maintained at 50%, the distance between the collector and the spinneret tip 20cm, the second support on the collector with a polyethylene having a melting point of about 120 ℃ as a second, poly A non-woven fabric (Namyang Nonwovens Co., Ltd., CCP40) having a thickness of about 200 µm and a basis weight of 40 g / m 2 formed of a low melting second composite fiber having an average diameter of 20 µm of propylene, and then a spinning nozzle pack using a high voltage generator A stack of nanofiber webs formed of PVDF nanofibers with an average diameter of 250 nm on one surface of the second support by applying a voltage of 40 kV to the spin nozzle pack and an air pressure of 0.03 MPa per spin pack nozzle. Sieve was prepared. The prepared nanofiber webs are each 35 wt% of the first nanofiber group having a diameter of 0.1 to 0.2 μm, the second nanofiber group having a diameter of 0.2 to 0.3 μm, and the third nanofiber group having a diameter of 0.3 to 0.4 μm, respectively. 53 wt% and 12 wt% were formed of nanofibers having an average diameter of 250 nm, a basis weight of 10 g / m 2, thickness of 13 μm, average pore diameter of 0.3 μm, and porosity of about 75%.

Next, the solvent and moisture remaining in the nanofiber web of the laminate were dried, and a calendering process was performed by applying heat and pressure at a temperature of 140 ° C. or higher and 1 kgf / cm 2 to thermally bond the second support and the nanofiber web. . 6, the second support body and the nanofiber web were thermally bonded as shown in FIG. 6, and the nanofiber web was implemented as a three-dimensional network structure as shown in FIGS. 5A and 5B.

Thereafter, the prepared laminate was immersed in the hydrophilic coating layer-forming composition prepared in the preparation example below, and dried at a temperature of 110 ° C. for 5 minutes in a dryer to prepare a hydrophilic coating layer on the nanofiber surface of the nanofiber web.

Thereafter, the laminate was disposed on both sides of the first support such that the second support faced the prepared laminate. At this time, the first support is 5mm thick, non-woven fabric having a basis weight of 450 g / m 2 formed of a low melting point second composite fiber having a melting point of about 120 ° C. and a polypropylene core of about 30 μm. (Southern Nonwoven Fabric, NP450) was used. After applying a heat of 140 ℃ and pressure of 1kgf / ㎠ to prepare a filter medium.

Comparative Example 1

The same procedure as in Example 1 was carried out, but without the pretreatment unit, only the osmosis filtration unit implemented a seawater desalination apparatus as shown in Table 1 below.

Comparative Example 2

The same procedure as in Example 1 was implemented, but the pre-treatment unit was configured using only the filter module without the electrocoagulation module in the pre-treatment unit to implement a seawater desalination device as shown in Table 1 below.

Experimental Example 1

The seawater desalination apparatus was operated under the same conditions by introducing seawater at a flow rate of 1 m ³ / h into the pretreatment unit of the seawater desalination apparatus according to Example 1, Comparative Example 1 and Comparative Example 2, and reverse osmosis membrane of the osmosis module during operation of the apparatus. The time of arrival of the replacement cycle was evaluated. As a result of the evaluation, the reverse osmosis membrane replacement cycle arrival time in the remaining examples and Comparative Example 2 was expressed as a relative percentage based on the replacement cycle arrival time of the reverse osmosis membrane in Comparative Example 1. At this time, the replacement cycle was evaluated based on the desalination flow rate obtained during the initial 30 hours of operation of the seawater desalination apparatus, by setting the time point at which the flow rate decreased by about 30% from the obtained flow rate.

Example 1 Comparative Example 1 Comparative Example 2 Preprocessor Electrocoagulation Module + Filter Module none Filter module Reverse Osmosis Membrane Backwash Time (%) 560 100 240

As can be seen from Table 1, in the case of Example 1 having both the electrocoagulation module and the filter module as a pretreatment before the osmosis filtration unit, it can be seen that the replacement time of the reverse osmosis membrane of the osmosis filtration unit can be significantly extended.

<Examples 2 to 16>

Manufactured in the same manner as in Example 1, but the filter medium as shown in Table 2 or Table 3 and the thickness / basis weight of the first support, the thickness / basis weight of the second support, the basis weight of the nano-sum web by changing the Table 2 or A filter medium as shown in Table 3 was prepared, and a seawater desalination device was implemented using the filter medium.

At this time, in the case of Example 12, the support of the specifications similar to Example 1 and the first support, the second support, respectively, using a low melting point polyester copolymer having a melting point of 142 ℃ and a core formed of a composite fiber of PET The filter medium was implemented by changing the first support body and the second support body and changing the temperature at 160 ° C., respectively.

Experimental Example 2

The following physical properties were evaluated for the seawater desalination apparatus employing each filter medium prepared in Examples, and are shown in Tables 2 and 3 below.

1. Initial Water Permeability Measurement

An operating pressure of 50 kPa was applied to the filter module to measure water permeability and filtration efficiency per 0.5 m 2 of one filter unit. In this case, the initial water permeability was calculated as a relative percentage of the water permeability of the filter unit implemented by the filter medium according to the remaining embodiments based on 100 of the water permeability of the filter unit implemented by the filter medium of Example 1.

2. Backwash Durability Evaluation

After separating one filter unit from the filter module and immersing the separated filter unit in water, backwashing was performed under the condition that pressurized 400LMH water for 2 minutes per 0.5m2 by applying an operating pressure of 50kPa. In the case of appearance abnormalities such as swelling during the process, backwash durability was evaluated as (x) when no abnormality occurred.

At this time, if the filter unit does not have any appearance abnormality when operating under 50kPa operation condition, the back pressure is increased by increasing the operating pressure, which is the pressurization condition exceeding the normal backwashing condition to 125kPa, and then evaluating the appearance abnormality. It was.

In addition, the water permeability after backwashing was measured in the same manner as the initial water permeability measuring method for the filter unit only when no external abnormality occurred when the backwashing was performed at an operating pressure of 125 kPa.

At this time, the water permeability was calculated as the rate of change according to Equation 1 for the water permeability (B) after backwashing the initial water permeability (A) of each specimen. The greater the rate of change, the more likely the damage of the nanofiber web due to backwashing or the delamination that does not appear abnormal in appearance.

% Change = {(B-A) × 100} ÷ A

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Nano Fiber Web Basis weight (g / ㎡) 10 20 29 25 10 10 10 10 Thickness (㎛) 15 25 40 40 15 15 15 15 Second support Basis weight (g / ㎡) 40 40 40 40 59 62 40 40 Thickness (㎛) 200 200 200 200 250 250 200 200 First support Basis weight (g / ㎡) 450 450 450 450 450 450 330 650 Thickness (㎛) 5000 5000 5000 5000 5000 5000 5000 5000 Overall filter media thickness (㎛) 5215 5225 5240 5240 5265 5265 5215 5215 Thickness ratio of the first support in the total thickness of filter media (%) 95.9 95.7 95.4 95.0 95.0 95.9 95.9 95.9 2nd support basis weight ratio based on nanofiber web basis weight 4 2 1.38 1.60 5.9 6.2 4 4 2nd support basis weight 1st support basis weight magnification 11.25 11.25 11.25 10.23 7.63 7.26 8.25 16.25 Initial Water Permeability (%) 100 92 82 88 96 91 100 86 Backwash Durability Abnormality
(@ 50kPa) × × × × × × × × Abnormality
(@ 125kPa) × × × × × × × × Permeability Change (%) 6.8 8.1 21.5 13.6 13.1 28.9 12.2 7.6

Example 9 Example 10 Example 11 Example 12 Example 13 Example 14 Example 15 Example 16 Nano Fiber Web Basis weight (g / ㎡) 10 10 10 10 10 10 10 32 Thickness (㎛) 15 15 15 15 15 15 15 40 Second support Basis weight (g / ㎡) 40 40 40 41 40 40 0 40 Thickness (㎛) 200 200 200 200 230 230 0 200 First support Basis weight (g / ㎡) 680 450 270 430 270 230 270 450 Thickness (㎛) 5000 3400 2200 5000 2000 2500 2200 5000 Overall filter media thickness (㎛) 5215 3615 2415 5215 2245 2745 2215 5240 Thickness ratio of the first support in the total thickness of filter media (%) 95.9 94.1 91.1 95.9 89.2 91.1 99.4 95.4 2nd support basis weight ratio based on nanofiber web basis weight 4 4 4 4.1 4 4 0 1.25 2nd support basis weight 1st support basis weight magnification 17 11.25 6.75 10.49 6.75 5.75 - 11.25 Initial Water Permeability (%) 84 87 80 100 79 87 94 76 Backwash Durability Abnormality
(@ 50kPa) × × × × × ○ ○ × Abnormality
(@ 125kPa) × × × × ○ Not performed Not performed ○ Permeability Change (%) 12.1 13.6 14.0 14.6 Unmeasured Unmeasured Unmeasured Unmeasured

As you can see in Table 2 and Table 3,

In the filter medium of Example 16 in which the basis weight of the nanofiber web exceeds 30 g / m 2, there was no appearance abnormality when the backwash was performed at a pressure of 50 kPa, but when the backwash pressure was 125 kPa, the nanofiber web was partially peeled off. The swelling phenomenon as in FIG. 17 occurred. On the contrary, in Examples 1 to 3 having a basis weight of 30 g / m 2 or less, it can be confirmed that no abnormality occurs when backwashing at a pressure of 125 kPa.

In addition, in Example 13 in which the thickness of the first support was less than 90% of the total filter media thickness, there was no abnormality in appearance due to backwashing when the backwashing was performed at a pressure of 50 kPa. This happened. On the contrary, in the case of Example 11, in which the thickness of the first support was 90% or more compared to the total thickness of the filter medium, the external pressure did not occur even though the pressure was increased to 125 kPa.

In addition, in Example 14 in which the basis weight of the first support was less than 250 g / m 2, the appearance abnormality occurred at 50 kPa backwash pressure even though the thickness of the first support was 90% or more relative to the total thickness of the filter media. It can be seen that the durability due to backwashing is significantly lowered than that of Comparative Example 1 due to the decrease in mechanical strength caused by washing.

In addition, in the case of Example 15 without the second support, it can be seen that the appearance abnormality occurred even when the back washing was performed at a pressure of 50 kPa. This is expected as a result of the weakening of the adhesion between the first support and the nanofiber web, despite having a first support that can withstand the pressure of backwashing as in Example 11 without the second support.

On the contrary, in the case of the eleventh embodiment having a basis weight of 250 g / m 2 or more, it can be seen that no abnormality in appearance occurs even under severe operating conditions of 125 kPa.

Meanwhile, in Examples 3 and 6, the basis weight of the second support may not fall within the range of 1.5 to 6 times based on the nanofiber web, compared to Examples 4 and 5 that are close to the above ranges. It can be seen that this was significantly high.

In addition, in the case of Example 6 and Example 9 in which the basis weight of the first support does not fall within the range of 8 to 16.5 times based on the second support, the water permeability fluctuation rate was significantly greater compared to Example 7 In Example 9, the water permeability fluctuation rate increased compared to Example 8, it can be seen that the initial water permeability significantly decreased.

In addition, even when the thickness of the first support is 90% or more of the total thickness of the filter media, the first support is 95% or more of the total thickness of the filter media. You can check.

In addition, in the case of Example 12 using the first support and the second support formed of a polyester-based low melting point composite fiber rather than polyolefin-based, when the backwash pressure is 125kPa, durability after backwashing was lowered, which is a brittle of the support It is expected that the adhesion was lower than that of Example 1, which is a polyolefin due to one physical property.

Although one embodiment of the present invention has been described above, the spirit of the present invention is not limited to the embodiments set forth herein, and those skilled in the art who understand the spirit of the present invention may add components within the scope of the same idea. Other embodiments may be easily proposed by changing, deleting, adding, etc., but this will also fall within the spirit of the present invention.

3100: supply pump 3200: pretreatment unit
100,100 ', 200,200', 3210: electrocoagulation module 3210: filter module
100,100 ', 200: Electrocoagulant 110,210: Housing
111: first chamber 112: second chamber
113: third chamber 114: partition wall
115: fitting groove 116,116 ': electrode case
117: fitting groove 118: discharge hole
119: drain pipe 120, 120 ': electrode unit
121,121 ': power electrode 122: sacrificial electrode
122 ': conductive mass 123: receiving member
123a: second discharge hole 123b: first discharge hole
130: inlet pipe 131: injection hole
140: control unit 150: diffuser
151: discharge hole
1,330, 430,530: first support
2,311,312,411,412,511,512: Nanofiber web
3, 321,322,421,422,521,522: second support
700: osmosis unit 710: outer housing
720: porous permeate outflow pipe 730: osmosis membrane
740: spacer
1000,1001,1002,1003,1004: filter medium 1100: support frame
2000: flat filter unit

Claims (15)

A pretreatment unit including an electroaggregation module for electrocoagulating the suspended substances contained in the introduced seawater, and a filter module for filtering the aggregates contained in the electrocoagulation water introduced from the electrocoagulation module; And
And an osmosis filtration unit having an osmosis membrane module for desalination of the pretreatment water introduced from the pretreatment unit.
The filter module includes a filter medium, and the filter medium includes a second support and a nanofiber web sequentially stacked on both surfaces of the first support, and the filtrate filtered from the nanofiber web is directed toward the first support. A flow path is formed, wherein the basis weight of the second support is 1.5 to 6 times the basis weight of the nanofiber web, the basis weight of the first support is 8 to 16.5 times the basis weight of the second support desalination apparatus. The method of claim 1,
The electrocoagulation module electroaggregates foreign matter contained in seawater through cations generated from the sacrificial electrode, and a seawater desalination device characterized in that a processing capacity of the introduced seawater is 1 m ³ / h or more. The method of claim 1,
The filter medium is a seawater desalination device, characterized in that the filtration flow rate is 50 LMH or more with respect to the electrocoagulation water flowing from the electrocoagulation module, the filtration efficiency is 99% or more for the aggregate having a particle diameter of 0.2㎛ or more. delete The method of claim 1,
The seawater desalination device, characterized in that the basis weight of the first support is 250 ~ 800g / ㎡, the thickness is 2 ~ 8mm. The method of claim 1,
The basis weight of the second support is 35 ~ 100g / ㎡, the thickness of the seawater desalination device, characterized in that 150 ~ 250㎛. The method of claim 1,
The nanofiber web includes a fluorine-based compound as a fiber forming component,
The fluorine-based compound may be polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymerization system, tetrafluoroethylene-hexafluoropropylene copolymerization system, tetrafluoroethylene-hexafluoropropylene- Perfluoroalkyl vinyl ether copolymers, ethylene-tetrafluoroethylene copolymers (ETFE) systems, polychlorotrifluoroethylene (PCTFE) systems, ethylene-chlorotrifluoroethylene copolymers (ECTFE) systems and polyvinylidene Desalination apparatus comprising at least one compound selected from the group consisting of fluoride (PVDF) system. The method of claim 1,
The nanofiber web has an average pore size of 0.1 to 5㎛, the seawater desalination device, characterized in that 60 to 90% porosity. The method of claim 1,
The nanofiber forming the nanofiber web is a seawater desalination device, characterized in that the average diameter of 0.05 ~ 1㎛. The method of claim 1,
The basis weight of the nanofiber web is 30g / ㎡ or less, the basis weight of the first support is 250g / ㎡ or more, the thickness is a seawater desalination device, characterized in that 90% or more of the total thickness of the filter medium. delete The method of claim 1,
The second support includes a second composite fiber disposed to expose at least a portion of the low melting point component to an outer surface, including a support component and a low melting point component, wherein the low melting point component of the second composite fiber is a nanofiber web. Fused to,
The first support includes a first composite fiber disposed to expose at least a portion of the low melting point component to an outer surface, including a support component and a low melting point component, and the low melting point component and the second composite of the first composite fiber. A seawater desalination device, characterized in that the first support and the second support are joined by fusion between the low melting point components of the fibers. The method of claim 1,
The filter unit is a flat filter unit further comprising a support frame for supporting the edge of the filter medium,
The support frame is a seawater desalination device, characterized in that it has a flow path for allowing the filtrate filtered in the filter medium to flow out. The method of claim 1, wherein the electrocoagulation module,
A housing having an inner space at an upper portion thereof; And
And an electrode unit disposed in the inner space and including a sacrificial electrode and a power electrode for agglomerating foreign matter contained in seawater supplied from the outside.
The internal space may include a first chamber into which the seawater is introduced, a second chamber disposed at an upper side of the first chamber, and a second electrode in which the electrode unit is disposed, and an electrocoagulation water in which the electrocoagulation reaction is completed in the second chamber is temporarily stored. Seawater desalination apparatus comprising three chambers. An electrocoagulation module for electrocoagulating foreign matter contained in the introduced seawater; And
And a filter module for filtering the aggregates contained in the electrocoagulated water introduced from the electrocoagulated module.
The filter module includes a filter media, and the filter media includes a second support and a nanofiber web sequentially stacked on both surfaces of the first support, and the filtrate filtered from the nanofiber web is directed toward the first support. A flow path is formed, wherein the basis weight of the second support is 1.5 to 6 times the basis weight of the nanofiber web, and the basis weight of the first support is 8 to 16.5 times the basis weight of the second support.

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