KR20170002047A - Purification system for potable water and ultra pure water - Google Patents

Abstract

The present invention relates to a system for producing ultrapure cooling water and drinking water. More specifically, provided is a system for producing ultrapure cooling water and drinking water, ensuring continuous operation of a water treatment process even when repairing or cleaning the processing apparatuses. To this end, a plurality of capacitive deionization (CDI) stacks for conducting brackish water desalination in a capacitive deionization method are connected in a parallel, some of the plurality of CDI stacks get to continuously conduct the water treatment process in turn.

Description

{Purification system for potable water and ultra pure water}

More particularly, the present invention relates to a system for producing drinking water and ultrarapid water supply and cooling water, in which a plurality of CDI stacks for performing desalination of a water by desalination are connected in parallel, The present invention relates to a drinking water and an ultrapure water supply / cooling water production system capable of continuously performing a water treatment process even in a cleaning or repairing process equipments by performing a water treatment process.

In recent years, the problem of water shortage has been worsening globally. Desalination of seawater, which accounts for about 97% of the water present on the earth, has become the most realistic way to solve the water shortage problem.

Water treatment techniques for seawater desalination can be roughly classified into physical treatment methods such as evaporation distillation and reverse osmosis membrane separation, biochemical treatment methods such as biodegradation or chemical oxidation and precipitation, electrochemical treatment such as electrodialysis or ion exchange The conventional water treatment process will be described with reference to the conventional seawater desalination process shown in FIG.

1 (a) is a seawater desalination process using a reverse osmosis RO (reverse osmosis). In order to make drinking water having a total dissolved solids (TDS) of 500 mg / L or less, a DAF (Dissolved Air Flotation) (Dual Media Filter), MF (Micro Filtration) or UF (Ultrafiltration), and then it produces Sea Water Reverse Osmosis (SWRO) process to produce TDS 1000 mg / L Brackish Water Followed by a BWRO (Brackish Water Reverse Osmosis) process, followed by a potableization process in which minerals such as CO ₂ and calcium are added.

1 (b) is a process for producing a large-capacity ultrapure water by using an ion exchange resin. The BWRO process is carried out in accordance with the method of FIG. 1 (a), and then a cation exchange resin is sequentially introduced. A decarbonator, and an anion exchanger. However, there is a problem in that the process is complicated and a large amount of regenerated wastewater is generated due to periodic regeneration of the ion exchange resin.

In recent years, the electrodeposition EDI (Electrode-Ionization) process as shown in FIG. 1 (c) has been developed to simplify the production of ultrapure water. However, the EDI process is based on 15 MΩcm and the operating conditions are continuous operation maximum pressure 5.5 bar, maximum current 9 A, maximum voltage 160 V DC, etc. Because the operation pressure and power consumption are high, the conventional ion exchange resin tower method used for large- Because it is preferred, another technical alternative is needed.

There arises a problem that the operation of the entire water treatment system must be stopped when the water treatment process equipment is further cleaned or a repair of the main water treatment process equipment is required due to a failure.

Patent Application No. 10-2015-0008348 Patent Application No. 10-2012-0133229

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the prior art as described above, and it is an object of the present invention to provide a method of performing a highly efficient desalination process while reducing power consumption of a seawater desalination process by applying a storage desalination (CDI) I want to present it.

In particular, the present invention solves the problem of performing a cleaning process for a water treatment process equipment or stopping the operation of the entire water treatment process when a repair of the main water treatment process equipment is required.

According to an aspect of the present invention, there is provided a system for producing drinking water and ultrapure water cooling water, comprising: a pretreatment means for generating nose water from seawater; And CDI stacks in which a plurality of CDI stacks for performing desalination of water by a storage desalination method are connected in parallel and control valves are provided in front of each of the CDI stacks, And the water treatment process is carried out alternately and continuously.

Preferably, the CDI means comprises: a power supply for supplying power to each of the plurality of CDI stacks; And controlling the power supply and the control valve such that one or more CDI stacks of the plurality of CDI stacks perform a deodorization treatment with ion adsorption and one or more of the remaining CDI stacks perform a cleaning process with ion desorption And a controller for selectively operating the CDI device.

More preferably, the pretreatment means may include a SWRO device for generating a nodal number from seawater using a reverse osmosis membrane.

And a cleaning means for supplying the cleaning liquid to the CDI means.

The cleaning means may be connected to the front and rear ends of the CDI means to clean one or more selected CDI stacks of the CDI means with a circulating CIP.

Further comprising a post-processing unit connected to a downstream end of the CDI unit to generate drinking water or ultrapure water from the pure water generated through the CDI unit.

Preferably, the post-treatment means may include a drinking water treatment facility for adding minerals to pure water.

Alternatively, the post-treatment means may include an ion exchange column for removing impurities.

Or the post-treatment means may sequentially include a cation exchange column, a decarbonated column and an anion exchange column.

Alternatively, the post-treatment means may comprise a mixed phase bed polisher.

Or the post-treatment means may comprise an EDI device for producing ultra pure water in an electrodeionization manner.

According to the present invention, it is possible to perform a highly efficient desalination process while reducing the power consumption of the seawater desalination process by applying the storage desalination (CDI) which is a low energy desalination technique.

Particularly, since a plurality of CDI stacks are provided in parallel, and some CDI stacks and the remaining CDI stacks are alternately subjected to the water treatment process, the water treatment process can be continuously performed even in the cleaning or repair of some process equipment.

Figure 1 shows a schematic diagram of a prior art water treatment process,
2 is a block diagram of an embodiment of a drinking water and ultrapure water supply / cooling water producing system according to the present invention,
3 is a block diagram of an embodiment of the CDI means in the drinking water and ultrapure water supply and cooling water production system according to the present invention,
FIG. 4 shows the operation of the CDI stack in the drinking water and ultrapure water supply and cooling water production system according to the present invention,
5 is a graph showing an example of a change in electric conductivity and a desalination process according to a voltage input condition for the CDI unit in the drinking water and the ultrapure water supply and cooling water production system according to the present invention,
FIG. 6 shows a configuration diagram of various embodiments of the drinking water and ultrapure water supply / cooling water production system according to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.

First, the terms used in the present application are used only to describe specific embodiments, and are not intended to limit the present invention, and the singular expressions may include plural expressions unless the context clearly indicates otherwise. . Also, in this application, the terms "comprise", "having", and the like are intended to specify that there are stated features, integers, steps, operations, elements, parts or combinations thereof, But do not preclude the presence or addition of features, numbers, steps, operations, components, parts, or combinations thereof.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In the present invention, a plurality of CDI stacks (stacks) for carrying out a desalination desalination system are connected in parallel, and a part of a plurality of CDI stacks and a remainder of the CDI stack are sequentially subjected to a water treatment process, Disclosed is a drinking water and ultrapure water supply / cooling water production system capable of continuously performing a water treatment process.

FIG. 2 shows a configuration diagram of an embodiment of a drinking water and ultrapure water supply / cooling water production system according to the present invention.

The drinking water and the ultrapure water supply and cooling water production system according to the present invention roughly includes a preprocessing means 100, a CDI means 200 and a post-processing means 400. The system includes a CDI means 200 as a main component, 100 and the post-processing means 400 can be selectively configured, and the detailed configuration of the preprocessing means 100 and post-processing means 400 can be appropriately modified as necessary.

The CDI unit 200, which is a main component of the drinking water and ultrarapid supply and cooling water production system according to the present invention, includes a plurality of CDI stacks 210a, 210b, 210c, ... 210d connected in parallel to constitute a CDI unit 210 , Wherein each CDI stack 210a, 210b, 210c, ... 210d is configured to perform a capacitive deionization (CDI) process of a capacitive desalination type, wherein the CDI process is performed by a non- , A technique for removing and treating an ionic material, means a water treatment method for removing cationic and anionic materials by an electro-dynamic technique.

The internal structures of the CDI stacks 210a, 210b, 210c, ... 210d may include various structures proposed for the CDI water treatment process. The present invention proposes a technical idea for effectively using the CDI process, The details of performing the self-configuration can be optionally modified according to need, so a detailed description thereof will be omitted.

Control valves 220a, 220b, 220c, and 220d for controlling the inflow of seawater or nadir to respective CDI stacks 210a, 210b, 210c, ..., 210d are provided in front of the respective CDI stacks 210a, 210b, 210c, ... 220d, and includes a control unit 300 for controlling the control valve 220. As shown in FIG.

In the present invention, a part of a plurality of the CDI stacks and a remaining part of the plurality of CDI stacks are alternately and continuously subjected to a water treatment process through the configuration of the CDI unit 200.

That is, the control unit 300 selects a part of the plurality of CDI stacks 210a, 210b, 210c, ..., 210d provided in the CDI unit 200, and supplies corresponding power supply and control valves 220a, 220b, 220c,... 220d to control the selected CDI stack to perform the water treatment by the storage desalination method. Then, the remaining CDI stacks that are not selected remain in the standby state or are washed immediately after the water treatment process of the selected CDI stacks by performing the washing process by ion desorption, and then the control unit 300 selects some of the remaining CDI stacks to perform the water treatment process Continuously without interruption.

The preprocessing means 100 processes dewatered air flotation (DAF), a dual media filter (DMF), and the like, Or may include a configuration for performing a pretreatment process such as MF (Micro Filtration) or UF (Ultra Filtration), or the pretreatment means 100 may include a SWRO device for generating a radix from seawater using a reverse osmosis membrane It is possible.

The post-treatment means 100 may include various structures for lowering impurities or salinity to increase the purity of pure water treated in the CDI means 200 up to ultrapure water. do.

FIG. 3 is a block diagram of a CDI unit in the drinking water and ultrapure water supply / cooling water production system according to the present invention.

In the system for producing drinking water and ultrarapid cooling water according to the present invention, the CDI unit includes a CDI unit 210 in which a plurality of CDI stacks 210a, 210b, 210c, 210d, ... 210n are connected in parallel, 210b, 210c, 210d,..., 210n are provided at the front ends of the control valves 210a, 210b, 210c, 210d, ... 210n.

And a power supply unit 350 that supplies power to the CDI device 210. The power supply unit 350 may supply power to the CDI stacks 210a, 210b, 210c, 210d, ..., .

The control valve 220 and the power supply unit 350 are controlled by the control unit 300. The control unit 300 controls the control valve 220 and the power supply unit 350, It is possible to individually control the water treatment performance of each of the CDI stacks 210a, 210b, 210c, 210d, ... 210n.

That is, the control unit 300 selects one or more CDI stacks in the CDI device 210, and one or more CDI stacks selected through the control of the control valve 220 and the power supply unit 350 corresponding thereto are subjected to ion- And can control the water treatment process to be continuously performed without interruption by alternately selecting each of the plurality of CDI stacks 210a, 210b, 210c, 210d, ... 210n.

Further, the control unit 300 may select one or more CDI stacks among the CDI stacks not to be subjected to the water treatment process to control the cleaning process by ion desorption.

In the present invention, an operation of the CDI stack to perform a cleaning process of a deodorizing water treatment process and an ion desorption process by ion adsorption is shown in FIG. 4. FIG. 4 shows an operation diagram of a CDI stack in a drinking water and ultrapure water supply and cooling water production system according to the present invention .

The CDI technique is based on the principle of adsorption and desorption of ions by an electric force in an electric double layer (EDL) formed at the interface of a charged electrode. Adsorption and desorption processes.

As shown in FIG. 4A, when a voltage is applied within a potential range (about 1.2 V) where no electrode reaction occurs, a certain amount of charge is charged to the electrode, and when salt water containing ions is passed through the charged electrode, Ions having opposite electric charges to the electrodes are moved to the respective electrodes by the electrostatic force and adsorbed on the electrode surface, so that the water having passed through the electrodes can be treated to remove ions.

Since the amount of ions adsorbed on the electrode is determined by the capacitance of the electrode used, a porous carbon electrode having a large specific surface area is generally used as the electrode used for CDI.

When the adsorption capacity of the electrode is saturated, no more ions can be adsorbed, and the ions of the influent water are directly discharged into the effluent. Therefore, a cleaning process of the CDI stack is required. As shown in FIG. 4 (b), the electrodes are short-circuited to desorb ions adsorbed on the electrodes to regenerate the electrodes, do. In this case, the electrodes lose charge or have opposite charges, so that the adsorbed ions are quickly desorbed and the electrode is regenerated.

In the present invention, it is possible to continuously perform the water treatment process through the CDI device 210 while alternately performing the adsorption and the desorption by alternately changing the potential of the electrode and a part of the plurality of CDI stacks.

3, the CDI unit according to the present invention will be described in further detail.

3, a SWRO device (not shown) is installed at the front end of the CDI device, and a reverse osmosis membrane (not shown) is used in the front end of the CDI device to store the process water subjected to the pretreatment process. Thereby generating a radix from the seawater and storing the radix in the radix tank 150.

 Then, a raw water pump 230 is installed to supply nose water from the nose tank 150 to the CDI means. At this time, the cartridge filter 240 is installed to interrupt the nuisance foreign matter.

According to the structure of the present invention as described above, the CDI unit alternately selects a plurality of CDI stacks 210a, 210b, 210c, 210d, ... 210n to perform a water treatment process and a cleaning process, And the salt water generated during the water treatment process flows into the separate salt water tank 290. [

Furthermore, fouling and scale are generated in the electrode and the ion exchange membrane in the cell stacked in the CDI stack through an electrical adsorption and desorption process. In order to remove such contamination, the present invention adopts a periodic cleaning process. In the embodiment of FIG. 3, as the cleaning means for supplying the cleaning liquid during the cleaning of the CDI means, the circulation type CIP (Cleaning In Place) to clean one or more selected CDI stacks of CDI measures.

For this purpose, a CIP tank 250 and a CIP pump 255 are installed. During the cleaning process, citric acid or the like is introduced to remove scale, and sodium hypochlorite (NaOCl) Thereby controlling biofouling.

As described above, the drinking water and the ultrapure water supply / cooling water production system according to the present invention includes a plurality of CDI stacks in parallel, and the CDI stack and the remaining CDI stacks alternately perform the water treatment process, The water treatment process can be continuously performed even in the situation.

FIG. 5 is a graph illustrating an example of change in electrical conductivity and desalination according to voltage input conditions for the CDI unit in the drinking water and ultrapure water supply and cooling water production system according to the present invention.

In the capacitive de-ionization (CDI) process applied in the present invention, when a positive charge and a negative charge are applied using a porous electrode such as activated carbon, the corresponding anions and cations are adsorbed on the counter electrode to desalinate, It is a low-energy type desalination technology that operates at an operating pressure of 0.5 to 1.0 bar at a voltage of 1.23 V or less and a concentration of influent water of 1.6 to 16 A and controls the voltage input conditions for the CDI stack As shown in FIG. 5, it is possible to more effectively control the desalination process according to the change of electrical conductivity by adjusting the voltage input conditions of the CDI stack proposed in the present invention.

2, the pre-processing unit 100 and the post-processing unit 400 of the drinking water and ultrapure water supply and cooling water producing system according to the present invention may be selectively changed in configuration as needed, In this regard, FIG. 6 shows a configuration diagram of various embodiments of the drinking water and the ultrapure water supply / cooling water production system according to the present invention.

In the various embodiments of FIG. 6, the pre-processing unit 100 may be configured to perform a preprocessing process such as Dissolved Air Flotation (DAF), Dual Media Filter (DMF), Micro Filtration (MF), or Ultra Filtration And a SWRO device 130 for generating nodal water from seawater using a reverse osmosis membrane.

6 (a), the post-treatment means 400a includes a drinking water treatment facility 410a for adding minerals such as CO ₂ and calcium, and the post-treatment means includes an ion exchange tower for removing impurities 6 (b), the post-treatment means 400b includes a boron ion adsorption tower 410b for selectively removing only boron in the case of inflow water containing high concentration of boron.

Further, as shown in FIG. 6C, the post-treatment means 400c may include both the boron ion adsorption tower 410b and the drinking water treatment facility 410c.

6 (d), the post-treatment means 400d includes a cation exchange column 410d, a decarbonation column 430d, an anion exchange column 450d and the like for producing ultrapure water using an ion exchange resin. .

In order to further simplify the complicated structure as shown in FIG. 6E and to treat the pure water obtained through the CDI process up to the level of the ultra pure water, the post-treatment means 400e includes a cation exchange resin and an anion exchange resin, And an ion exchange resin tower (Mixed bed polisher) 410e.

6 (f), the post-processing means 400f includes an EDI device 410f for generating ultrapure water in an electrodeionization system. In this way, the ultra-pure water is produced through the EDI process, It is also possible to adopt a point that the generation of waste liquid is small and the operation is simple.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments of the present invention are not intended to limit the scope of the present invention but to limit the scope of the present invention. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents thereof should be construed as being included in the scope of the present invention.

100: preprocessing means,
110: preprocessing configuration, 130: SWRO device
150: Rider tank,
200: CDI means,
210: CDI device,
210a, 210b, 210c, 210d, 210n: CDI stack,
220, 220a, 220b, 220c, 220d: control valve,
230: raw water pump, 240: cartridge filter,
250: CIP tank, 255: CIP pump,
270: Pure tank, 290: Salt water tank.

Claims (11)

A pretreatment means for generating a nose from seawater; And
CDI stacks in which a plurality of CDI stacks for carrying out a basin desalination in a storage desalination system are connected in parallel and control valves are provided in front of each of the CDI stacks,
Wherein a part of the plurality of CDI stacks and a remaining part of the plurality of CDI stacks alternately perform a water treatment process in succession. The method according to claim 1,
Wherein the CDI means comprises:
A power supply unit for supplying power to each of the plurality of CDI stacks; And
Wherein the at least one CDI stack of the plurality of CDI stacks is controlled by the power supply unit and the control valve to perform a storage desalination water treatment process by ion adsorption and at least one of the remaining CDI stacks is subjected to a cleaning process Further comprising a controller for selectively operating the CDI device. The method according to claim 1,
The pre-
And a SWRO device for generating nodal water from seawater using a reverse osmosis membrane. The method according to claim 1,
Further comprising cleaning means for supplying a cleaning liquid to the CDI means. 5. The method of claim 4,
The cleaning means,
Wherein the CDI stack is connected to the front end and the rear end of the CDI unit to clean one or more CDI stacks selected from among the CDI units using a circulating CIP (Cleaning In Place). The method according to claim 1,
Further comprising post-processing means connected to a downstream end of the CDI means for generating drinking water or ultrapure water from the pure water generated through the CDI device. The method according to claim 6,
The post-
Characterized in that the system comprises a drinking water system for adding minerals to pure water. The method according to claim 6,
The post-
And an ion exchange column for removing impurities. The method according to claim 6,
The post-
Wherein the system comprises a cation exchange column, a decarboxylation column and an anion exchange column sequentially. The method according to claim 6,
The post-
And a mixed-phase ion exchange resin tower (Mixed bed polisher). The method according to claim 6,
The post-
And an EDI device for generating ultrapure water by an electric deionization system.

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