KR20140144341A - Electrical deionization type water treatment apparatus and the control method thereof - Google Patents

Abstract

A water treatment apparatus according to the present invention includes: an electrical deionization type filter which can support a water purification mode for purifying water with supplied source water and a regenerative mode for producing regenerated water; a first concentration level sensor for measuring the concentration of the source water supplied to the electrical deionization type filter; and a control unit for controlling the filter voltage applied to the interval between the anode and the cathode of the electrical deionization type filter according to the concentration of the source water measured in the first concentration level sensor.

Description

TECHNICAL FIELD [0001] The present invention relates to an electrolytic deionization type water treatment apparatus,

The present invention relates to an electric deionization type water treatment apparatus and a control method thereof, and more particularly, to an electric ionization type water treatment apparatus and a control method thereof for controlling a constant current so that a regeneration current flowing between an anode and a cathode is constant in a regeneration mode .

A water treatment apparatus, such as a water purifier, for treating raw water to generate a purified water is now being variously disclosed. However, recently, the most popular method for water treatment system is EDI (Electro Deionization), CEDI (Continuous Electro Deionization), and CDI (Capacitive Deionization). Among them, the CDI system is the most popular in recent years.

The CDI method refers to a method of removing ions (contaminants) using the principle that ions are adsorbed and desorbed from the surface of an electrode by an electric force. 6 and 7, when raw water containing ions is passed between the electrodes (positive electrode and negative electrode) while a voltage is applied to the electrodes, the negative ions move to the positive electrode as shown in FIG. 6 And the cations move to the cathode. (That is, adsorption occurs). Such adsorption can remove ions in the raw water.

However, when such adsorption continues, the electrode is no longer able to adsorb ions. When this state is reached, as shown in FIG. 7, ions adsorbed to the electrode are desorbed to regenerate the electrode. (At this time, the regenerated water is generated and discharged.) Such regeneration can be achieved by applying no voltage to the electrode, or by applying a voltage as opposed to when adsorbing.

In the regeneration process and the purification process of the CDI type water treatment apparatus, the constant voltage applied between the anode and the cathode is constantly used as the constant voltage (constant potential) control. However, since the conventional electrolytic deionization type water treatment apparatus performs constant voltage control in the regeneration process, the following problems arise. First, when constant voltage control is performed during the regeneration process, a large amount of current flows at the beginning of the regeneration process because the adsorbed ions are rapidly desorbed at the beginning, and this current may damage the electrode. Second, due to the constant voltage control, the initial abrupt desorption causes a high concentration of ions such as Ca / Mg, which causes a scale (hard crystal), so that the scale generation possibility in the electrodeionization type water treatment apparatus becomes high.

Therefore, it is required to improve the problems of the constant voltage control of the conventional electrolytic deionization type water treatment apparatus.

Accordingly, it is an object of the present invention to provide an electric deionization type water treatment device and an electric deionization type water treatment device in which a constant current is controlled so that a regeneration current flowing between an anode and a cathode is constant in a regeneration mode, And to provide a control method thereof.

It is another object of the present invention to provide a method of setting the current value of the constant current control in the regeneration mode.

The water treatment apparatus according to the present invention includes: an electric deionization type filter having a purified mode for generating purified water by receiving raw water and a regeneration mode for generating regenerated water; And a control unit for controlling a voltage and a current applied between the anode and the cathode of the electrodeionization type filter. The controller controls the constant current so that the regeneration current flowing between the anode and the cathode is constant in the regeneration mode.

Preferably, the controller controls the constant voltage so that the constant voltage applied between the anode and the cathode is constant in the constant mode.

Preferably, the control unit sets the regeneration current in the regeneration mode based on the constant current flowing between the anode and the cathode in the constant mode.

Preferably, the control unit sets the regeneration current in the regeneration mode based on the constant current flowing between the anode and the cathode in the constant mode immediately before the regeneration mode.

Preferably, the control unit sets the regeneration current in the regeneration mode as the integral current integral value obtained by integrating the constant current in the constant mode into the constant time in the constant mode / the regeneration time in the regeneration mode.

Preferably, the control unit includes a constant current monitor for monitoring the constant current of the constant mode.

Preferably, the control unit sets the average value X of the constant currents at the two time points of the integer mode (integer time in the integral mode / reproduction time in the reproduction mode) as the reproduction current in the reproduction mode.

Preferably, the two points in the integer mode are the two points after a certain period of time since the start of the integer.

Preferably, the electrodeionization type filter is a CDI type filter or an EDI type filter.

A control method of an electric deionization type water treatment apparatus according to the present invention, which has an integer mode in which raw water is supplied and a regeneration mode in which a purified water is generated and a regeneration mode in which a regenerated water is generated, A constant voltage control step of an integer mode for controlling the constant voltage; And a regeneration mode constant current control step of controlling the regeneration current flowing between the anode and the cathode in the regeneration mode to be constant.

Preferably, the constant voltage control step includes a constant current storage step for storing a constant current value flowing between the anode and the cathode in the integer mode.

Preferably, the constant voltage control step further includes a regeneration current setting step of setting a regeneration current value of the regeneration mode based on the constant current value stored in the constant current storage step.

Preferably, in the regeneration current setting step, the regeneration current is set to a constant current integral value obtained by integrating the constant current of the constant mode into the constant time of the constant mode / regeneration time of the regeneration mode.

Preferably, in the regeneration current setting step, the regeneration current is set to an average value X (integer time in integer mode / regeneration time in regeneration mode) of the constant current at two points in the constant mode.

In the electrodeionization type water treatment apparatus according to the present invention, since the initial desorption amount and the later desorption amount between the electrodes are maintained in the regenerative mode under the constant current control, the effect of preventing electrode damage and scale formation can be obtained.

In addition, since the regeneration current in the regeneration mode is set based on the constant current flowing between the positive and negative electrodes in the constant mode, a suitable current can be set, and therefore power consumption of the water purifier can be prevented.

1 is a flow chart of an integer mode of an electric deionization type water treatment apparatus according to the present invention;
2 is a flowchart of a regeneration mode of the electrolytic deionization type water treatment apparatus according to the present invention.
3 is an exploded perspective view of the electrode part and the electrode part of the electrodeionization type filter according to the present invention.
4 is a graph showing a current value in the constant mode of the electrolytic water treatment apparatus according to the present invention
5 is a flowchart of a control method of an electric deionization type water treatment apparatus according to the present invention.
FIG. 6 is a conceptual diagram illustrating the principle of making constants in the electrodeionization type filter. FIG.
7 is a conceptual diagram illustrating the principle of regeneration in the electrodeionization type filter.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited or limited by the following examples.

Electricity Deionization  Water treatment system

Referring to FIG. 1, the water treatment apparatus 10 according to the present invention includes: an electric deionization type filter 20 having an intrinsic mode for receiving raw water to generate purified water and a regeneration mode for generating regenerated water; And a control unit 30 for controlling voltage and current applied between the anode and the cathode of the electric deionization type filter.

The electrodeionization type filter 20 includes an electrode portion 21 and an electrode case (not shown). The electrode portion 21 of the electrodeionization-type filter 20 includes an anode 22 and a cathode 23. More specifically, as shown in Fig. 3, the electrode portion 21 is formed by alternately laminating the anode 22 and the cathode 23. [ At this time, the electrode portion 21 includes a separator 24 (or a spacer) between the anode 22 and the cathode 23. The separator 24 forms an interval between the anode 22 and the cathode 23. That is, the raw water passes between the anode 22 and the cathode 23 through the separator 24 and is purified. The purified water purified in the electrodeionization type filter 20 is stored in the purified water supply unit 50.

The electric deionization type filter 20 has an integer mode in which raw water is supplied to generate purified water and a regeneration mode in which regenerated water is generated.

Referring to Fig. 1, the integer mode of the water treatment apparatus 10 according to the present invention will be described. In the constant mode, the control unit 30 controls the constant voltage so that the constant voltage applied between the anode and the cathode is constant. If constant current control is performed so that the constant current flowing between the anode and the cathode is constant in the constant mode, as the adsorption of ions to the electrode increases, the efficiency of the electrode decreases and the decrease of the impurity removal rate becomes large. On the other hand, when the constant voltage control is performed in the constant mode, the voltage required for removing the impurity is kept constant, so that the decrease in the impurity removal rate is not large. Therefore, constant voltage control is preferably performed in the constant mode.

Meanwhile, the control unit 30 of the water treatment apparatus 10 according to the present invention measures and stores the amount of the constant current flowing in the constant mode. The constant current amount in this constant mode is used for setting the regeneration current value in the constant current control of the regeneration mode to be described later.

Referring to Fig. 2, the regeneration mode of the water treatment apparatus 10 according to the present invention will be described. The raw water supplied from the raw water supply unit 40 is discharged as regenerated water together with ions desorbed through the electrodeionization type filter 20. At this time, the control unit 30 controls the constant current so that the regeneration current flowing between the anode and the cathode is constant.

As described in the Background of the Invention, when the constant voltage control is performed in the regeneration mode, electrode damage due to the high current at the initial stage of the regeneration mode occurs and excessive desorption of scale generation ions such as Ca / Mg The scale generation is disadvantageous. However, when the constant current control is performed in the regeneration mode, since the initial desorption amount and the later desorption amount are kept substantially the same, the electrode damage by the high current can be prevented, and the desorption of the initial high concentration scale generation ion can be prevented.

On the other hand, in order to perform the constant current control in the regeneration mode, it is necessary to set the current value. Since the conventional electrolytic deionization type water treatment apparatus does not consider the constant current control in the regeneration mode, no method of determining the current value is disclosed at all. The method of setting the current value for the constant current control in the regenerative mode according to the present invention will now be described in detail.

play Current value  How to set up

The regeneration current in the regeneration mode of the electrodeionization type filter 20 according to the present invention is set based on the constant current flowing between the anode and the cathode in the constant mode. Since the regeneration mode desorbs the amount of ions adsorbed in the constant mode, the amount of current flowing in the constant mode is the amount of current that must flow in the regeneration mode. The constant current amount stored in the controller 30 in the integer mode described above is used for setting the regeneration current value in the regeneration mode. Preferably, the regeneration current value is set based on the constant current flowing between the anode and the cathode in the constant mode immediately before the regeneration mode. In the constant mode, it is preferable to set the regeneration current based on the constant current value in the constant mode immediately before the regeneration mode since the constant current control and the current flowing between the anode and the cathode is not constant for each constant mode. A specific method of setting the regeneration current value will be described below.

First Playback Current Setting Method

The first regenerating current setting method is a method of regenerating the regenerating time (RT) of the regeneration mode by integrating the constant current integral value obtained by integrating the constant current mode (Purifying A: PA) into the integer time (Purifying Time: PT) Is set to a regenerating current (Regenerating A) (RA). That is, the method of obtaining the reproduction current RA can be expressed by the following equation.

Since the first reproduction current setting method uses integration, the reproduction current value can be obtained most accurately. The current values according to time in the current value graph according to time in the integer mode of FIG. 4 are summarized in the table below.

Time (seconds) Current value in constant mode (A) One 0.075574 5 0.063640 10 0.061065 15 0.059322 20 0.057469 25 0.057438 30 0.055444 35 0.056386 40 0.054439 45 0.055193 50 0.054282 55 0.054423 60 0.053968 65 0.053732 70 0.053936 75 0.053198 80 0.053952 85 0.052555 90 0.053701

The value of the regenerative current according to the first regenerative current setting method is as follows.

     = 5.055 / 80 = 0.0632 [A] (PT = 90 seconds, RT = 80 seconds)

Therefore, when the constant current control is performed for 80 seconds with 0.0632A regeneration current value in the regeneration mode, the amount of current flowing in the constant mode and the amount of the current flowing in the regeneration mode become equal.

The control unit 30 preferably includes a constant current monitor for monitoring the constant current. The constant current monitor unit measures and stores the constant current value in the constant mode.

How to set the second playback current

The second reproduction current setting method sets a value obtained by multiplying the average value of the constant currents at the two points of time (p1, p2) of the integer mode by the ratio of the constant time and the reproduction time to the reproduction current. That is, the method of obtaining the reproduction current RA can be expressed by the following equation.

In order to apply the first regeneration current setting method, the constant current value during the constant time in the constant mode must be stored in a predetermined time unit (for example, 0.5 second, 1 second, etc.) . Further, since the process of integrating them is necessary, the processing of the control section 30 becomes complicated. Accordingly, in the second regeneration current setting method, instead of integrating the constant current values during the constant time, the average of the constant current values at the two points (p1, p2) in the constant mode is used.

On the other hand, it is preferable to set the time point after the constant time to two points in time after the start of the constant. Referring to the graph of FIG. 4, since an unstable section appears after a significant increase of the constant current before about 9 seconds, for example, the time after 9 seconds can be set to two points. In addition, the two viewpoints can be set to be symmetrical to the first viewpoint p1 after a certain period of time after the start of the integer mode and the second viewpoint p2 before the end of the integer mode. For example, you can set two points at 10 seconds (p1) after the start of the integer mode and 80 seconds (p2) of 10 seconds before the end of the integer mode.

(P1) and 80 seconds (10 seconds before completion) (p2) according to the second regeneration current setting method in the current value graph in the constant current controlled constant mode in Fig. 4, As follows.

     = (0.061065 + 0.053952) / 2 x (90/80) = 0.0647 [A]

       (PT = 90 seconds, RT = 80 seconds)

In the same manner, 15 seconds (p1) and 75 seconds (15 seconds before the end) (p2) are defined as two points, and 20 seconds (p1) and 70 seconds 2 The regeneration current values obtained according to the regeneration current setting method are summarized in the table below.

2 points (10 seconds) 2 points (15 seconds) 2 points (20 seconds) Integral value Reproduction current value 0.0647 0.0633 0.06277 0.0632

As can be seen from the above table, it can be seen that the difference between the regeneration current value obtained through the integral value and the regeneration current value obtained by the average value at the two-point time point does not appear much. Therefore, the second regenerative current setting method has an advantage of obtaining the regenerative current value by a simple calculation formula.

Electricity Deionization  Control method of water treatment system

Referring to FIG. 5, a control method of an electric deionization type water treatment apparatus having an integer mode that receives raw water and generates purified water and a regeneration mode that generates a regenerated water, according to the present invention, A constant voltage control step (S100) of an integer mode for controlling the constant voltage to be constant; And a regenerative mode constant current control step (S200) for controlling the regeneration current flowing between the positive electrode and the negative electrode to be constant in the regeneration mode.

The constant voltage control step S100 includes a constant current storing step S110 for storing a constant current value flowing between the anode and the cathode in the constant mode. The constant current value in the constant mode which is the basis of the setting of the regeneration current value to be used in the regenerative current control of the regeneration mode is stored in the constant current storage step (S110). In the case of using the first regeneration current setting method described above, when the constant current value is stored in a constant time unit (for example, 0.5 second, 1 second, etc.) for an integer time and the second regeneration current setting method is used, And stores the constant current value at the time point 2.

The constant voltage control step S100 further includes a regeneration current setting step S120 for setting a regeneration current value of the regeneration mode based on the constant current value stored in the constant current storage step S110. In the reproducing current setting step (S120), the reproducing current is determined according to the current value setting method according to the present invention described above.

10: water treatment device 20: electric deionization type filter
30: control unit 40: raw water supply unit
50:

Claims (15)

An electric deionization type filter having an integer mode for receiving raw water and generating a purified water and a regeneration mode for generating a regenerated water; And
And a control unit for controlling a voltage and a current applied between the anode and the cathode of the electrodeionization type filter,
Wherein the controller controls the constant current so that a regeneration current flowing between the anode and the cathode is constant in the regeneration mode.
The method according to claim 1,
Wherein the controller controls the constant voltage so that the constant voltage applied between the anode and the cathode is constant in the constant mode.
The method according to claim 1,
Wherein the controller sets the regeneration current in the regeneration mode based on a constant current flowing between the anode and the cathode in the constant mode.
The method of claim 3,
Wherein the controller sets the regeneration current in the regeneration mode based on the constant current flowing between the anode and the cathode in the constant mode immediately before the regeneration mode.
The method of claim 3,
Wherein the control unit sets the regeneration current of the regeneration mode as the regeneration current of the regeneration mode (the integral current integral value obtained by integrating the constant current of the constant mode into the constant time of the constant mode) .
The method of claim 5,
Wherein the controller includes a constant current monitor for monitoring the constant current in the constant mode.
The method of claim 3,
Wherein the controller sets the average value X of the constant currents at two points in the integer mode (integer time in integer mode / reproduction time in the reproduction mode) as the regeneration current in the regeneration mode, Device.
The method of claim 7,
Wherein the two points of time in the integer mode are two points after a certain time elapses after the start of the water purification.
The method according to any one of claims 1 to 8,
Wherein the electric deionization type filter is a CDI type filter or an EDI type filter.
A control method for an electric deionization type water treatment apparatus having an integer mode in which raw water is supplied to generate purified water and a regeneration mode in which a regenerated water is generated,
A constant voltage control step in an integer mode for controlling the constant voltage applied between the anode and the cathode in the constant mode to be constant; And
And a regeneration mode constant current control step of controlling the regeneration current flowing between the anode and the cathode to be constant in the regeneration mode.
The method of claim 10,
Wherein the constant voltage control step includes a constant current storing step of storing a constant current value flowing between the anode and the cathode in the constant mode.
The method of claim 11,
Wherein the constant voltage control step further comprises a regeneration current setting step of regenerating a regeneration current value in a regeneration mode based on the constant current value stored in the constant current regeneration step.
The method of claim 12,
Wherein the regeneration current is set to an integral current integral value obtained by integrating the constant current in the constant mode into an integer time in an integer mode / a regeneration time in the regeneration mode in the regeneration current setting step. A method of controlling a device.
The method of claim 12,
Wherein the regeneration current is set to an average value X (integer time in integer mode / regeneration time in regeneration mode) of the constant current at two points in the constant mode in the regeneration current setting step Control method of water treatment apparatus.
15. The method of claim 14,
Wherein the two points of time in the integer mode are two points after a predetermined time elapses after the start of the water purification.

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