JP2001239275A - Water treating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water treating device for treating water to be treated, with which water to be treated, containing various organic carbon compounds in various concentrations can be treated without such as erroneous operation that driving of a cleaning means is stopped before the organic carbon compounds are treated completely or conversely, the cleaning means is driven beyond necessity, and which is capable of treating the water rapidly and efficiently. SOLUTION: In the water treating device equipped with a cleaning means for oxidizing and decomposing organic carbon compounds contained in water to be treated, a pH detection section for detecting pH value of the water in the cleaning means and a controlling section for controlling the drive of the water treating device according to the pH value detected by the pH detection section are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water treatment apparatus provided with a purifying means for oxidatively decomposing organic carbon compounds of water to be treated.

[0002]

2. Description of the Related Art Conventionally, as a method for oxidizing organic carbon compounds in water causing water pollution or air pollution, ozone treatment or a combined oxidation method using an oxidizing agent in combination with radiation, ultrasonic waves, electrolysis, and the like are known. I have.

[0003]

However, the conventional water treatment apparatus as described above does not know the concentration of the organic carbon compound in the water to be treated when the purification means is driven. For this reason, the operation of the purifying means is stopped even though the organic carbon compound of the water to be treated is not completely treated, or the purifying means is driven more than necessary, and the running time becomes longer. There was a problem that the cost wasted.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has provided a mechanism for grasping whether or not the water to be treated has been purified with respect to the water to be treated having various concentrations of organic carbon compounds. Accordingly, an object of the present invention is to provide a water treatment apparatus capable of treating treated water quickly and without waste.

[Means for Solving the Problems and Functions / Effects]

In order to solve the above-mentioned object, a water treatment apparatus according to the present invention is a water treatment apparatus provided with a purifying means for oxidatively decomposing organic carbon compounds of the water to be treated. A pH detection unit for detecting the value, and a control unit for controlling the operation of the water treatment apparatus based on the pH value detected by the pH detection unit.

First, the mechanism of decomposition of an organic carbon compound by the oxidative decomposition method will be described. Organic carbon compounds decomposed by the oxidative decomposition method are decomposed into carbon dioxide and water via intermediates such as aldehydes, ketones, and carboxylic acids. Also, the carboxylic acid is hardly decomposed even in the intermediate,
It is also used as the final form of intermediates generated in the process of decomposing organic compounds. Therefore, it can be said that the time when the carboxylic acid disappears is the time when the organic carbon compound is treated.

Here, as an example, FIG. 1 shows a graph in which methanol is decomposed by a combined oxidation method using ultraviolet light and hydrogen peroxide in combination. Here, TOC means total organic carbon, which indicates the concentration of organic matter in water. When this value is 0, it means that water does not contain organic matter. According to this figure, when methanol is decomposed in the complex oxidation method,
It turns out that formic acid which is a carboxylic acid is formed together with the aldehyde which is an intermediate. In addition, since the carboxylic acid is acidic, the oxidative decomposition reaction proceeds, and it can be seen that the pH value of the water to be treated decreases as the concentration of formic acid increases. When the organic matter in the treated water is completely decomposed (TOC = 0), that is, when formic acid, which is the final form of the intermediate, is decomposed, the pH value of the water to be treated returns to almost the pH value before the treatment. It turns out to be stable. Due to this, the pH value decreases due to the generation of carboxylic acid during the treatment, and the organic substance is completely decomposed. The operation of the purifying means is not stopped even if the organic carbon compound is not completely treated, and conversely, the purifying means is not driven more than necessary.

Preferably, the control section has a storage means for storing a pH value before the start of the purification process, and a comparison section for comparing the pH value detected after the start of the purification process with the pH value stored in the storage section. A purifying process is stopped when the decreased pH value rises and stabilizes.

[0009] From this, it can be immediately recognized that the water to be treated has been treated, and the operation of the purifying means can be stopped by the control unit, so that the purifying means is not operated more than necessary. Fast and efficient processing can be performed.

[0010] More preferably, an on-off valve is provided in a flow path for discharging water from the purifying means to the outside, and the control unit prohibits the on-off valve from being opened during the purifying process.

Thus, the open / close valve is opened after the treatment of the water to be treated by the purifying means, so that the untreated water is not discharged from the purifying means.

[0012] Preferably, a pH detector and a stirrer are provided in the purifying means.

Thus, when detecting the pH concentration, the water to be treated in the purifying means is stirred by the action of the stirring device, so that there is no deviation in the concentration of the treated water in the purifying means,
Regardless of the installation position of the detection unit, the concentration of the whole water to be treated can be accurately grasped.

[0014] It is further preferable that a data storage unit for storing information detected by the pH detection unit is provided.

Thus, when the purifying means is operated, it is possible to detect a decrease in the processing capacity of the purifying means by comparing it with past processing data, and to detect an abnormality of the purifying means from the measured data.

Further, preferably, there is provided a notifying means for notifying an abnormality of the purifying means from the information of the data storage unit.

Thus, it is possible to recognize the abnormality of the purification means without disassembling the apparatus or directly measuring the concentration of the organic carbon compound or the like in the water to be treated.

Preferably, the purifying means comprises a reaction vessel and an ultraviolet lamp so that water can be purified by an oxidative decomposition method, and the ultraviolet lamp is an excimer lamp.

Conventionally, as the oxidative decomposition method, a composite oxidative method in which organic substances are oxidatively decomposed in combination with an oxidizing agent such as ozone or hydrogen peroxide has been used because of its low oxidizing power. For example, a combined oxidation method such as ultraviolet light using ozone and a low-pressure mercury lamp, ozone and electrolysis method, and ozone and radiation. However, there is a problem that sufficient decomposition is not performed unless the injection amount of the oxidizing agent to be added is controlled according to the concentration of organic substances in the water to be treated. Here, FIG. 2 shows the relationship between the wavelength of ultraviolet light and the irradiation intensity at the same power consumption of the low-pressure mercury lamp and the excimer lamp used in the complex oxidation method. From this figure, it can be seen that the use of an excimer lamp allows efficient emission of ultraviolet light in the vacuum ultraviolet region that contributes to the decomposition of organic substances. Thus, the use of an excimer lamp as an ultraviolet lamp has a large output of vacuum ultraviolet light that contributes to the decomposition of organic substances. This eliminates the need to add and control an oxidizing agent.

[0020] More preferably, the ultraviolet light has a peak wavelength of 150 to 200 nm.

The shorter the wavelength of ultraviolet light, the higher the energy of photons. The energy of photons having a wavelength of 200 (nm) or less can easily break bonds such as C = C in organic compounds that are difficult to decompose. When the wavelength is 200 (nm) or less, ultraviolet rays are absorbed by water, and active species having strong oxidizing power and contributing to decomposition of organic substances are generated. From this, the wavelength 200 (n
m) By using the following ultraviolet rays, organic substances can be efficiently decomposed by decomposition by ultraviolet rays and decomposition by active species. Incidentally, ultraviolet rays having a wavelength of less than 150 (nm) do not pass through quartz, so that practical use is difficult.

In a further preferred aspect, the excimer lamp is a lamp that emits ultraviolet light having a main wavelength of 172 nm.

A xenon excimer lamp having a main wavelength of 172 nm can stably output ultraviolet light having a higher output than other excimer lamps at a high electrical conversion efficiency. It can be decomposed and removed efficiently.

More preferably, the excimer lamp is housed in a protective tube through which ultraviolet light can pass, and the protective tube has a pressure of 300 Torr or less or a gas which does not absorb ultraviolet light having a wavelength of 150 to 200 (nm). It is characterized by having an atmosphere containing as a main component.

In the process of transmitting the ultraviolet light through the atmosphere, the ultraviolet light decomposes organic matter and moisture in the air and absorbs them. The degree of absorption is large with vacuum ultraviolet rays. When ultraviolet rays having a wavelength of 185 nm or less are used, they react with oxygen to generate ozone. Therefore, with the above configuration, the ultraviolet rays emitted from the lamp can be sufficiently irradiated on the water to be treated without the ultraviolet rays being absorbed in the lamp protection tube.

More preferably, the inner wall of the reaction vessel is made of a material that reflects ultraviolet rays.

As a result, even if a part of the ultraviolet light emitted from the ultraviolet lamp is transmitted to the inner wall of the reaction vessel without contributing to the decomposition of organic substances, the ultraviolet light is reflected by the inner wall. It can be used for organic matter decomposition of the water to be treated. Therefore, the ultraviolet light emitted from the ultraviolet lamp can be effectively used without waste.

BEST MODE FOR CARRYING OUT THE INVENTION

An embodiment of the present invention will be described below with reference to FIG. FIG. 3 shows details of the purifying means. In FIG. 3, 1 is a water supply port, 2 is a reaction vessel, 3 is an excimer lamp, 4 is a stirrer, 5 is a pH detector, 6 is a controller that controls the driving of the excimer lamp according to the pH concentration of the water to be treated, 7 Is a data storage unit that stores information detected from the pH detection unit, 8 is a notification unit that notifies an abnormality of the purification unit,
Reference numeral 9 denotes an on-off valve.

Next, the operation of this embodiment will be described. First, water to be treated is supplied to the reaction vessel 2 through the water supply port 1. The inner surface of the reaction vessel 2 is made of a material that reflects ultraviolet rays. Next, the treated water is stirred by the stirring device 4, the pH value before the treatment is detected by the pH detection unit 5, and the information is stored in the data storage unit 7. Thereafter, the excimer lamp 3 is turned on with the stirring device 4 being driven, and the organic carbon compound is decomposed. At this time, the pH value of the water to be treated is detected by the pH detection unit 5 at regular time intervals, and the information is stored in the data storage unit 7.

Here, when the organic carbon compound is oxidatively decomposed in the above decomposition process, the organic carbon compound is decomposed into carbon dioxide and water via an intermediate such as aldehyde, ketone, and carboxylic acid. . Since carboxylic acid is acidic, the pH value of the treated water decreases as the organic carbon compound is decomposed and the carboxylic acid concentration increases, and when the carboxylic acid finally formed is also decomposed, the pH value of the treated water becomes Almost before processing
Returns to pH value and stabilizes. Here, the carboxylic acid is hardly decomposed among the intermediates, and is also used as a final form of the intermediate generated in the process of decomposing the organic carbon compound. Therefore, when the carboxylic acid has disappeared, it can be said that the organic carbon compound has been treated.

For this reason, data is obtained such that the pH value of the processing solution usually decreases and returns to almost the pH value before the treatment, and the pH value stabilizes. At this point, the exciter lamp 3 is turned off by the control unit 6, and the process is terminated. In the graph of methanol decomposition in FIG. 1, the purifying means is stopped at the stage P in the figure. The on-off valve 9 is controlled by the control unit 6, is closed during the purification process, is opened after the completion of the purification process, and the treated water in the reaction vessel 2 is discharged.

In the above operation, it is determined by the comparison means in the control unit 6 that the pH value detected after the start of the purification process and the pH value stored in the storage unit are not reduced. In this case, it is considered that the excimer lamp is abnormal, and the abnormality is reported by the reporting means 8. Also, when the rate of decrease in pH is slower than the past purification data stored in the data storage unit 7, it is regarded as an abnormality such as a decrease in the output of the excimer lamp, and the abnormality is reported by the reporting unit 8.

Here, FIG. 4 is a flowchart showing a series of operations of the water treatment apparatus in the decomposition of the organic carbon compound described above. V0 is the pH value before treatment, and Vn is the n-th p detected by the pH detection unit at regular time intervals after the excimer lamp is turned on.
H value. Vn 'is the data processed during the previous processing
The nth is the pH value detected by the pH detection unit.

Although an excimer lamp has been described as an example of the purifying means in the embodiment of the present invention, any water treatment method by oxidative decomposition may be used, and a method using ultrasonic waves may be used.

The present invention is not limited to this embodiment. A sensor that measures the oxidation-reduction potential can also be used.

By performing the above operation, a mechanism for grasping whether or not the water to be treated has been completely purified with respect to the water to be treated having various concentrations of organic carbon compounds is provided. It is possible to provide a water treatment device that can treat the treated water and detect an abnormality of the purification device.

[Brief description of the drawings]

FIG. 1 is a graph showing the decomposition behavior of methanol by a combined oxidation method using ultraviolet light and hydrogen peroxide in combination.

FIG. 2 is a graph showing the relationship between the ultraviolet wavelength and the ultraviolet intensity of the low-pressure mercury lamp and the excimer lamp with the same power consumption.

FIG. 3 is a diagram showing a first embodiment of the present invention.

FIG. 4 is a view showing a series of operations of a water treatment apparatus in decomposing an organic carbon compound.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Water supply port 2 ... Reaction tank 3 ... Excimer lamp 4 ... Stirrer 5 ... pH detection part 6 ... Control part 7 ... Data storage part 8 ... Notification means 9 ... On-off valve

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shinra Endo 2-1-1 Nakajima, Kokurakita-ku, Kitakyushu-shi, Fukuoka Tochiki Kiki Co., Ltd. (72) Inventor Shigeru Ando Nakajima, Kitakyushu-shi, Fukuoka 2-Chome 1-1 No.1 Toto Kiki Co., Ltd. F term (reference) 4D037 AA01 AB01 BA18 BB01 BB02 BB09 CA11 4D050 AA01 AB07 AB11 AB14 BB09 BC09 BD02 BD08

Claims (11)

[Claims] 1. A water treatment apparatus provided with a purifying means for oxidatively decomposing an organic carbon compound of water to be treated, wherein a pH detecting unit for detecting a pH value of the water to be treated in the purifying means; A control unit for controlling the drive of the water treatment device based on the detected pH value. 2. The control unit according to claim 1, further comprising a storage unit configured to store a pH value before the start of the purification process, and a comparison unit configured to compare a pH value detected after the start of the purification process with the pH value stored in the storage unit. 2. The water treatment apparatus according to claim 1, wherein the purification treatment is stopped when the decreased pH value rises and becomes stable. 3. The cleaning device according to claim 1, wherein an on-off valve is provided in a flow path for discharging water from the purifying means to the outside, and the control unit prohibits the on-off valve from being opened during the purifying process. Water treatment equipment. 4. The water treatment apparatus according to claim 1, further comprising a pH detector and a stirrer in said purifier. 5. A data storage unit for storing information detected by the pH detection unit.
5. The water treatment apparatus according to 4. 6. The water treatment apparatus according to claim 5, further comprising a notifying unit for notifying an abnormality of the purifying unit based on the information of the data storage unit. 7. The water according to claim 1, wherein said purifying means comprises a reaction vessel and an ultraviolet lamp so that water can be purified by an oxidative decomposition method, and said ultraviolet lamp is an excimer lamp. Processing equipment. 8. The water treatment apparatus according to claim 7, wherein a peak wavelength of the ultraviolet light emitted from the excimer lamp is 150 to 200 nm. 9. The water treatment apparatus according to claim 7, wherein the excimer lamp is a lamp that emits ultraviolet light having a main wavelength of 172 nm. 10. The excimer lamp is housed in a protective tube through which ultraviolet rays can pass, and the protective tube has a pressure of 300 Torr.
The water treatment apparatus according to claim 7, wherein the atmosphere is mainly composed of a gas that does not absorb ultraviolet light having a wavelength of 150 to 200 (nm). 11. The reaction vessel according to claim 7, wherein an inner wall of the reaction vessel is made of a material that reflects ultraviolet rays.
0 water treatment apparatus.