JP4864671B2 - Water quality abnormality detection device, water quality abnormality detection method, and water treatment device - Google Patents

Description

  The present invention relates to a water quality abnormality detection device and a water quality abnormality detection method, and further relates to a water treatment device using this device. More specifically, the treated water discharged from the outlet side of the water treatment unit is passed through the measurement column and the comparison column connected in parallel, and water quality abnormality is detected based on the detection result of the test object. The present invention relates to a water quality abnormality detection device, a water quality abnormality detection method, and a water treatment device.

  Conventionally, pure water production technology for increasing the purity of water from city water or industrial water has been studied. In particular, in the field of advanced technology, when manufacturing semiconductors, ultrapure water is required, so a technology for manufacturing ultrapure water from city water or industrial water is required. In order to produce this ultrapure water, it is necessary to remove impurities in the water. Specifically, cations, carbon dioxide gas, anions and the like contained in water are removed. In general, in a pure water production system, cations contained in raw water are removed by a cation exchange resin tower of a water treatment unit, and then degassed to remove carbon dioxide, and then an anion exchange resin tower. The ions are removed and then treated with a reverse osmosis membrane.

Here, the cation contained in water includes monovalent ones such as sodium ion (Na ⁺ ) and potassium ion (K ⁺ ), calcium ion (Ca ²⁺ ), magnesium ion (Mg ²⁺ ) and the like. These cations are collectively called “cations”.

  As these cations have a higher atomic weight and valence, the binding force with the ion exchange resin is higher. In addition, since the water flow time of the ion exchange resin of the water treatment unit is short and most of the cations are ion exchanged while the ion exchange capacity is large, the amount of cation leakage is small, but the water flow time of the ion exchange resin is long. As the ion exchange capacity decreases, the amount of cation leakage increases.

Here, it is difficult to completely remove sodium ions (Na ⁺ ) and potassium ions (K ⁺ ) having a small valence through an ion exchange resin, and a slight amount of leakage is unavoidable, but it dissolves in water. It is easy to cause troubles such as clogging in each unit of the water treatment device.

On the other hand, dihydric or higher hardness components such as calcium ions (Ca ²⁺ ) and magnesium ions (Mg ²⁺ ) tend to be solid compounds, and they pass through each unit. Prone to clogging. Specifically, when divalent or higher cation leaks from the ion exchange column, the reverse osmosis membrane on the downstream side of the pure water production apparatus is clogged, and the function of the pure water production apparatus is stopped. Therefore, in order to stably operate the pure water production apparatus, it is necessary to constantly monitor the amount of cation leak from the ion exchange tower.

For this reason, in a conventional pure water production apparatus, a cation detection device is arranged on the treated water outlet side of the ion exchange tower, so that calcium ions (Ca ²⁺ ) and magnesium ions (Mg ²⁺ ) in the treated water are more than bivalent. The ion exchange capacity of the ion exchange resin is monitored by analyzing the presence or absence of hardness components. In this conventional cation detection apparatus, a karma guide colorimetric method is used, a karma guide indicator is added to the treated water, the color development is measured with light having a wavelength of 520 nm, and the amounts of calcium ions and magnesium ions are measured.

  However, this method requires a complicated analysis device such as a quantitative pure water device, a constant temperature device, a quantitative injection device, a reagent storage device, a stirring device, a constant light source light emitting device, a constant current conversion device, and a calculation device. Analyzing devices composed of these devices have high analysis accuracy, but are expensive, complicated, delicate and prone to failure. In particular, there are many disturbance factors such as vibration, heat, gas, electromagnetic waves and the like at manufacturing sites such as factories, and there is a problem that it is not easy to maintain the function of a precise analyzer.

Therefore, as a structure that is simpler and less likely to fail, and that can detect leak cations at low cost and high accuracy, a comparison column that is filled with ion exchange resin and connected to the outlet side of the water treatment unit , A first pH meter disposed upstream of the comparison column in the water movement direction, a second pH meter disposed downstream of the comparison column in the water movement direction, and the first pH meter. A cation detection device, a cation detection method, and a water treatment device to which the cation detection method is applied, and a calculation means for calculating a cation leak rate in treated water based on the meter comparison value and the second pH meter comparison value are known. (See Patent Document 1).
JP 2001-56323 A

  However, in this cation detection method, the first pH meter and the second pH meter are respectively arranged upstream and downstream with respect to the direction of water movement of the comparison column, and there is a difference in measurement time. For example, when the quality of the raw water changes over time, the difference in time is measured by comparing the upstream water and the downstream water at the time of comparison. As a result, accurate measurement may not be possible.

  Therefore, the present invention provides a water quality abnormality detection device and a water quality abnormality detection method capable of accurately detecting an abnormality regarding the water quality abnormality of treated water in the water treatment unit even when a change in the quality of raw water occurs. It is for the purpose.

  The water quality abnormality detection device of the present invention allows the treated water discharged from the outlet side of the water treatment unit to pass through, the measurement column and the comparison column of the same volume connected in parallel, and the water movement of the measurement column. Water quality measuring instrument disposed downstream in the direction, comparative water quality measuring instrument disposed downstream in the direction of water movement of the comparison column, measurement values by the water quality measuring instrument, and comparative water quality measuring instrument And a calculation means for calculating the degree of water quality abnormality based on the comparison value obtained by (1).

  In the water quality abnormality detection method of the present invention, the treated water discharged from the water treatment unit is passed through the measurement column and the comparison column of the same volume connected in parallel, and after passing through the measurement column. Measure the quality of the treated water and use it as a measured value. Measure the quality of the treated water after passing through the comparison column and use it as a comparative value. Monitor the difference between the measured value and the comparative value to detect abnormal water quality. It is characterized by calculating the degree of.

  Further, the water treatment apparatus of the present invention includes a water treatment unit, a measurement column and a comparison column of the same volume connected in parallel to the outlet side of the water treatment unit, respectively, and a downstream side in the water movement direction of the measurement column. The water quality measuring instrument for measurement, the comparative water quality measuring instrument disposed downstream of the comparison column in the direction of water movement, the comparative value by the measuring water quality measuring instrument, and the comparative value by the comparative water quality measuring instrument And calculating means for calculating the degree of water quality abnormality based on the above.

  The water treatment unit in the present invention is a unit unit having a function of removing impurities contained in water to be treated in an apparatus for water treatment, such as a sand filter, a cation exchange resin tower, an anion exchange resin tower, Examples include a mixed bed ion exchange tower, an activated carbon tower, and an ion exchange polisher.

  In addition, the column for measurement in the present invention is filled with an inert packing material on the inspection object, while the comparison column is filled with an active packing material on the inspection object. . Here, the inspection object refers to a substance to be removed in the upstream water treatment unit connecting the water quality abnormality detection means. For example, if the water treatment unit is a cation exchange resin tower, the cation and water treatment The unit is an anion in an anion exchange resin tower, the water treatment unit is a particulate filter in a sand filter, and the water treatment unit in activated carbon is chlorine.

  In addition, these measurement column and comparison column are the same volume column, and when this is the same volume, when measuring the quality of the treated water that has passed through the measurement column and the comparison column, respectively. Thus, it is possible to compare the measured values so as not to cause a difference in elapsed time as much as possible.

  Here, the packing to be packed in the measurement column is inactive with respect to the inspection object, and the inactivity with respect to the inspection object does not cause an action of removing the inspection object. Thus, the water discharged from the water treatment unit passes through the column without changing the water quality. Examples of the filler that is inert to the test object include glass beads.

  The packing packed in the comparison column is active with respect to the test object, and the activity with respect to the test object means that the test object is removed, for example, When the test object is a cation, a cation exchange resin, a mixed bed ion exchange resin, and when the test object is an anion, the anion exchange resin, the mixed bed ion exchange resin, and the test object are In the case of particulate impurities, sand for filtration, in the case where the inspection object is chlorine, activated carbon, and in the case where the inspection object is an impurity contained in pure water or ultrapure water, it is mixed. It is a floor type ion exchange resin.

  At this time, it is preferable that the porosity when the packing is filled in the measurement column and the comparison column is the same, and the treated water passing through each column is made to be the same because the porosity is the same. In order to flow through the column at the same speed, the water to be measured thereafter is processed by the water treatment unit at the same time, passes through the measurement column and the comparison column at the same time, and the water quality is measured at the same time. Therefore, measurement that is not affected by changes in the quality of raw water is possible.

  Here, furthermore, the use of the packing used in the measurement column and the comparison column having the same shape and the same average particle diameter adjusts the porosity of the measurement column and the comparison column to be the same. This is particularly preferable from the viewpoint of easily performing the above.

  Next, as the water quality measuring instrument used in the present invention, the measuring water quality measuring instrument and the comparative water quality measuring instrument each directly or indirectly measure the same item (inspection object), and are used here. Examples of the water quality measuring device include a pH meter, a conductivity meter, a resistivity meter, a turbidity meter, and a chlorine meter. These may be used alone or in combination of a plurality of items. Good.

  Moreover, as a water treatment apparatus of this invention, the water treatment unit and the water quality abnormality detection apparatus of this invention are provided in the treated-water outlet side, Here, as a water treatment unit, the apparatus which performs water treatment Is a unit unit having a function of removing impurities contained in the water to be treated, and any known water treatment unit can be used without particular limitation. Examples of the water treatment unit include a sand filter, a cation exchange resin tower, an anion exchange resin tower, a mixed bed ion exchange tower, activated carbon, and an ion exchange polisher. Any water treatment apparatus using a water treatment unit may be used, and examples thereof include a pure water production apparatus and an ultrapure water production apparatus.

  In the present invention, the measurement column and the comparison column, the water quality measuring device arranged in the subsequent stage of each column, and the calculation means are configured in a simple combination of existing devices. It is possible to provide a water quality abnormality detection device, a water quality abnormality detection method, and a water treatment device that have a simple structure, are less likely to fail, are inexpensive, and can detect water quality abnormality with high accuracy.

Hereinafter, the present invention will be described in detail based on embodiments with reference to the drawings.
FIG. 1 is a diagram showing a schematic configuration of an ultrapure water production apparatus 1 according to the present embodiment.
In this ultrapure water production apparatus 1, an ion exchange unit 10, a deaeration unit 20, and a reverse osmosis filtration unit 30 are arranged in series with respect to the direction of movement of water, and these ion exchange unit 10, deaeration unit 20, and reverse The osmotic filtration units 30 are connected by pipes 101 and 102. Further, a pipe 103 for introducing raw water is connected to the ion exchange unit 10, and a pipe 104 for supplying the obtained ultrapure water to the outside is attached to the reverse osmosis filtration unit 30. A pipe 101 connecting the ion exchange unit 10 and the deaeration unit 20 is branched halfway and a pipe 105 is attached. The pipe 105 is a pipe for sampling the treated water ion-exchanged by the ion exchange unit 10, and a water quality abnormality detection device 40 is attached to the end of the pipe 105.

When the pure water production apparatus 1 is activated, a pump (not shown) is operated to supply raw water into the pipe 103. The raw water supplied into the pipe 103 first flows into the ion exchange unit 10. In the ion exchange unit 10, the raw water that has flowed in comes into contact with an ion exchange resin packed in the ion exchange tower of the unit, so that ion exchange treatment is performed, and most of so-called cations are exchanged for H ⁺ ions. The treated water that has been subjected to the ion exchange treatment in the ion exchange unit 10 is sent to the subsequent deaeration unit 20 through the pipe 101 except for the part that is branched next in the pipe 105. The water sent to the deaeration unit 20 is deaerated here to remove carbon dioxide in the water, and then enters the reverse osmosis filtration unit 30 through the pipe 102, where ions and Impurities such as organic substances are removed, and are sent out of the apparatus as treated water through the pipe 104.

  The ion exchange unit 10 comprises a single or a plurality of ion exchange columns 11. 2 is a partially enlarged view in which an attachment portion of the ion exchange tower 11 and the water quality abnormality detection device 40 is enlarged. As shown in FIG. 2, the ion exchange unit 10 is filled with a large amount of ion exchange resin 12 in an ion exchange column 11.

  FIG. 3 is a diagram showing a schematic structure of a water quality abnormality detection device 40 according to the present invention. As shown in FIG. 3, in the water quality abnormality detection device 40, the treated water that has flowed into the pipe 105 branched by the pipe 101 is further branched to the pipes 105a and 105b, 105a for the measurement column 41, and 105b for comparison. Connected to the column 42, the measurement column 41 and the comparison column 42 are connected from the bottom to pipes 105c and 105d for discharging treated water treated with the packing material inside the column, respectively.

  Moreover, in order to inspect the quality of the water flowing down the pipes 105c and 105d, detection units 43 and 44 are provided, respectively. The detection unit 43 controls the pH of the treated water flowing down the measurement column by the pH electrode 45. It is arranged so as to be in contact with the liquid through the chamber for measurement, and the detection unit 44 is in contact with the liquid through the chamber for measuring the pH of the treated water flowing down the comparison column by the pH electrode 46. The detection unit 43 is connected to the measurement pH meter 47 and transmits the measured pH data, and the detection unit 44 is connected to the comparison pH meter 48 and measured. pH data is transmitted.

  Both the measurement pH meter 47 and the comparison pH meter 48 are electrically connected to the arithmetic processing unit 49 so that the cation leakage rate is calculated based on the pH data detected by the pH electrodes 45 and 46, respectively. It has become. Calculation processing such as the cation leak rate will be described later.

  The measurement column 41 is filled with glass beads that are inert to cations. In this measurement column 41, water is introduced into the measurement column 41 from the top and filled therein. While coming into contact with the glass beads, the liquid is discharged from the bottom of the measurement column 41 and flows out to the pipe 105c.

  The comparison column 42 is filled with a cation exchange resin. In this comparison column 42, water is introduced into the comparison column 42 from the top thereof, and the cation exchange resin filled therein is While coming into contact, the liquid is discharged from the bottom of the comparison column 42 and flows out to the pipe 105d.

  The measurement treated water that has flowed out of the pipe 105c comes into contact with the measurement pH electrode 45 disposed in the pipe, and the pH is measured. Further, the comparative treated water that has flowed out into the pipe 105d comes into contact with the comparative pH electrode 46 disposed in the pipe, and the pH is measured. The measurement treated water and the comparative treated water, each of which has been subjected to pH measurement, further flow down the pipe, and finally merge and are discharged out of the system.

  The measured values and the comparative values obtained by measuring the pH with the measuring pH electrode 45 and the comparative pH electrode 46 are the pH meters 47 and 48 electrically connected to the pH electrodes 45 and 46 and the arithmetic processing unit. 49. The arithmetic processing unit 49 that has received the data signal of the measured pH value and the comparative value obtains the pH obtained from the treated water flowing down the measurement column 41 from the received signal data and the treated water flowing down the comparison column 42. The cation leakage rate is calculated from the measured pH. Hereinafter, the cation leak rate measurement principle of the water quality abnormality detection device of the present invention will be described.

In the water quality abnormality detection apparatus 1 of the present invention, cations (cations) in the raw water are exchanged into H ⁺ ions by the ion exchange unit 10, and these are passed through the measurement column 41 and the comparison column 42, respectively.

Even if the treated water that has passed through the ion exchange unit 10 is passed through the measurement column 41, it is filled with cations and inert glass beads that are filled in this column, and immediately after the ion exchange unit 10 is discharged. Water quality including treated water and H ⁺ ion concentration does not change, and H ⁺ ion concentration can be measured by pH value. When cations that have not been completely ion-exchanged by the ion exchange unit 10, that is, cations leaked from the ion exchange unit 10, H ⁺ ions are reduced by the amount containing the leaked cations, and the pH is increased. The cation concentration of the treated water is determined by measuring the H ⁺ ion concentration at the outlet of the measurement column 41 with the measurement pH electrode 45.

On the other hand, since the comparison column 42 is filled with a cation exchange resin that adsorbs leaked cations (active with cations), all the leaked cations are exchanged with H ⁺ ions, and the comparison column 42 has an outlet at the outlet. There are always H ⁺ ions equal to the cation concentration of the raw water. The cation concentration of the raw water is determined by measuring the H ⁺ ion concentration at the outlet of the comparison column 42 with the comparison pH electrode 46.

Then, by subtracting the H ⁺ ion concentration of the raw water measured by the comparative pH electrode 46 from the H ⁺ ion concentration measured by the measurement pH electrode 45, the concentration of the net leak cation is obtained.

  Here, factors such as the pH of water treated by passing through the measurement column 41, the pH of water treated by passing through the comparison column 42, and the leak rate of the ion exchange resin are indicated by the following symbols.

pH _IN : pH of water treated with a measurement column (−), pH _OUT : pH of water treated with a comparison column (−), H _IN : Water treated with a measurement column (eq / L), H _OUT : Water treated with a comparison column (eq / L), L: Leak rate (%)

At this time, the relationship of H ⁺ = 10 ^−pH is obtained from the equation pH = −log [H ⁺ ]. Accordingly, when a cation leak occurs from the ion exchange unit 10, the pH is reduced by the amount of the leak. Therefore, the cation leak rate is given by the following equation.
L = (H _OUT −H _IN ) / H _OUT (%)

Next, the cation leakage state when the ultrapure water production apparatus 1 of the present invention is continuously operated will be described.
FIG. 4 is a diagram schematically showing the ion exchange state in the ion exchange resin column and the comparison column, and FIG. 5 shows the relationship between the operation time and the pH change amount (ΔpH) based on the change in the cation leak amount. It is a graph.

In the initial stage (time t1-t3) when only a short time has elapsed since the start of operation of the ultrapure water production apparatus shown in FIG. 4 (1), the ion exchange capacity of the ion exchange resin in the ion exchange resin column is sufficiently high. The cations flowing from the top of the column are efficiently ion-exchanged into H ⁺ ions in the ion exchange column. At this time, leak cations do not flow into the measurement column and the comparison column drawn on the lower side of the ion exchange column. Therefore, the value difference ΔpH between the pH meter of the measurement column and the pH meter of the comparison column is zero.

  Next, in the middle period (time t4) after continuous operation for a predetermined period, as shown in FIG. 4 (2), the ion exchange capacity of the ion exchange resin has been reduced, and the cation has diffused to the vicinity of the bottom of the column. Yes. At this stage, cations have diffused to most of the ion exchange column, but cations have not leaked to the outside of the ion exchange column yet. Therefore, cations do not flow into the measurement column and the comparison column on the downstream side of the ion exchange column, and therefore the difference ΔpH between the pH meter of the measurement column and the pH meter of the comparison column is zero. It is.

In the later stage (time t5) after continuous operation, the ion exchange capacity of the ion exchange resin decreases as shown in FIG. 4 (3), and the ions flowing from the raw water into the ion exchange column are ion exchanged. It becomes impossible to complete. As a result, a part of the cations overflows from the ion exchange column, and flows out to the downstream side of the ion exchange column with alkali ions (Na ⁺ ) that are not ion-exchanged with H ⁺ ions. Water containing alkali ions (Na ⁺ ) flowing out downstream of the ion exchange column flows into the measurement column and the comparison column, respectively.

In the measurement column, the water of the quality that has flowed in is discharged, and the pH is measured through the measurement pH meter. At this time, since the measured water contains alkali ions (Na ⁺ ) leaking from the ion exchange column, the pH value is, for example, from 3.2 when only H ⁺ ions are contained. High 4.2.

On the other hand, in the comparison column, Na ⁺ contained in contact with the ion exchange resin filled with the inflowing water is ion-exchanged into H ⁺ ions. Therefore, the water flowing out downstream of the comparative column contains only H ⁺ ions, and therefore the pH of the water measured by the downstream pH meter of the comparative column is 3.2 in the case of containing only H ⁺ ions. Indicates the value of.

Here, since the pH value of the water that has passed through the measurement column is 4.2 and the pH value of the water that has passed through the comparison column is 3.2, the difference is ΔpH = 1.000.
The CPU as a calculation unit (not shown) connected to the measurement pH meter and the comparison pH meter obtains ΔpH from the detected pH data, and grasps the cation leakage status from this value.

  Specifically, the relationship between the value of ΔpH and the amount of leaked cation is stored as a database, and by referring to this database, the pot life of the ion exchange resin in the ion exchange column is obtained, and if necessary, the ion exchange resin It is displayed that it is necessary to exchange for a new one, or an alarm is issued.

Further, as shown in FIG. 5, with the deterioration of the ion exchange resin in the ion exchange column, at time t1 and time t3, the water whose pH is measured by the upstream pH meter contains only H ⁺ ions. In addition, ΔpH is zero or close to a low level. At time t4-t5, when the ion exchange capacity of the ion exchange resin decreases with the extension of the operation time, Na ⁺ ions leak into the water whose pH is measured by the pH meter for measurement, so that the pH value rises and ΔpH The value of increases. When the ion exchange capacity of the ion exchange resin further decreases until time t6, a divalent hardness component such as Ca ²⁺ ion or Mg ²⁺ ion, which is an ion having a larger atomic weight and valence than Na ⁺ ion, is obtained. Will leak. When these hardness components leak, the pH of the water whose pH is measured by the measurement pH meter rises and ΔpH also increases.

Therefore, in the present invention, only the Na ⁺ ion leaks, and the value of ΔpH before the divalent hardness component such as Ca ²⁺ ion and Mg ²⁺ ion leaks is grasped from preliminary experiments and measured values. When ΔpH reaches this value, an alarm is issued or a signal is sent to notify that the ion exchange capacity of the ion exchange resin has dropped to near the limit.

  The actual range of the ΔpH value is a design matter, and is determined based on theoretical values, actual measurement values, preliminary experiment data, and the like.

In this way, the structure is such that the ion exchange capacity of the ion exchange resin is lowered when ions with high solubility such as Na ⁺ ions and leakage of ions that do not cause clogging of the reverse osmosis membrane are leaked. Further, it is possible to prevent the occurrence of an enormous trouble that the hardness component leaks and clogs the reverse osmosis membrane and eventually stops the entire ultrapure water production apparatus.

  Moreover, about the change of the water quality by the time difference of treated water, the comparative test was done with the water treatment apparatus of patent document 1 made into the prior art example, and the water treatment apparatus in this invention.

  First, tap water and pure water were mixed as the water to be treated, and the mixing ratio was changed with time so that the quality of the water to be treated changed with time. The state of change in the conductivity of the water to be treated at this time was adjusted so as to change periodically as shown in FIG.

  After treating the water to be treated with an ion exchange unit, the conventional method described in Patent Document 1 measures and compares the pH upstream and downstream of the comparison column, and the method of this embodiment. As shown in FIGS. 7 and 8, the pH changes of the water flowing out in the measurement column and the comparison column are measured and compared. FIG. 7 and FIG.

  FIG. 7, which is data obtained by the conventional method, compares the data of water having different time qualities, that is, the pH to be compared is upstream and downstream, that is, water having different water qualities. The changes do not coincide and a predetermined phase shift occurs. On the other hand, FIG. 8, which is data obtained by the method of the present embodiment, shows that water to be compared is measured at the downstream of each of the measurement column and the comparison column, and is simultaneously supplied to the ion exchange unit. Since the exchange unit was discharged and passed through the measurement column and the comparison column for the same amount of time, the water data with the same water quality was compared with each other. It can be seen that comparison and measurement can be performed without being affected by changes in water quality.

  As described above in detail, in the ultrapure water production apparatus 1 of the present invention, a sampling branch pipe is provided on the downstream side of the ion exchange column, and a measurement column, a comparison column, and their columns are provided in this branch pipe. A pH meter was provided on each downstream side, and cation leakage from the ion exchange column was detected by the magnitude of the difference between the two pH values for water that passed through the measurement column and the comparison column.

  Therefore, the structure of the device is simple and difficult to break down, and the water for measurement and the water for comparison are ion-exchanged water at the same time, and there is no time lag in water quality. A cation leakage state can be detected.

  Similarly, as shown in FIG. 9, after the treatment by the primary pure water system 110, the mixed water ion exchange unit (MB) 120, the pure water tank 130, and the polishing system 140 are sequentially passed through the treated water. In addition, the water quality abnormality detection device 40 is provided downstream of the MB 120, or after the treatment by the polishing system 210 as shown in FIG. 10, the treated water is passed through the polisher 220 and the ultrafiltration membrane (UF) 230 in order. When processing and supplying treated water to the use point 240, the water quality abnormality detection device 40 may be provided downstream of the polisher 220. In these cases, a mixed bed type ion exchange resin is preferably used as the packing packed in the comparison column, and a specific resistance meter is provided in place of the pH meter, and an abnormality is detected by measuring the specific resistance value. It is preferable to configure as described above.

  In addition, this invention is not limited to the range described in the said embodiment. For example, in the above-described embodiment, a structure in which a water quality abnormality detection device capable of detecting cations is provided in a part of the ultrapure water production device, but the water quality abnormality detection device is provided in a water treatment device other than the ultrapure water production device. It is also possible to do.

  In this embodiment, the cation leak can be detected. However, the anion, particulate impurities, chlorine leak, and impurities contained in pure water or ultrapure water can be detected. You can also. At this time, as a water quality abnormality detection device, anion exchange resin is used for the comparison column in the case of anion, sand for filtration is used in the comparison column in the case of particulate impurities, and activated carbon is used in the comparison column in the case of chlorine. In the case of impurities contained in pure water or ultrapure water, a mixed bed type ion exchange resin may be used.

  The cation exchange resin and the anion exchange resin are not particularly limited as long as they are publicly known, for example, gel type, porous type, strong acid cation exchange resin, weak acid cation exchange resin, strong base anion exchange resin, Weak base anion exchange resins and the like can be used without limitation, and these can be used alone or in combination. Moreover, as sand for sand filtration, if it is well-known as sand used as a filter medium, it can be used without particular limitation, for example, sand having a particle diameter of 0.3 to 1.2 mm can be used, An anthracite layer may be provided similarly to sand filtration. The activated carbon can be used without particular limitation as long as it is a known one, and may be any of wood, coconut plant, coal, petroleum, and the shape thereof is powder, granular, fibrous, etc. Can be used.

It is the figure which showed schematic structure of the water treatment apparatus which concerns on this invention. It is the elements on larger scale of the ion exchange unit which concerns on this invention, and a water quality abnormality detection apparatus attachment part. It is the figure which showed schematic structure of the water quality abnormality detection apparatus which concerns on this invention. It is the figure which showed typically the ion exchange state in the ion exchange unit of the water quality abnormality detection apparatus which concerns on this invention, and a comparison column. It is the graph which showed the relationship between the operation time of the water treatment apparatus which concerns on this invention, and pH variation. It is the figure which showed the change of the electrical conductivity of the raw | natural water used by the test example. It is the figure which showed the pH change at the time of pH measurement of a prior art example in a test example. It is the figure which showed the pH change at the time of pH measurement of this invention in a test example. It is the figure which showed schematic structure of the other water treatment apparatus which concerns on this invention. It is the figure which showed schematic structure of the other water treatment apparatus which concerns on this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Water treatment apparatus, 10 ... Ion exchange unit, 20 ... Deaeration unit, 30 ... Reverse osmosis membrane unit, 40 ... Water quality abnormality detection apparatus, 41 ... Measurement column, 42 ... Comparison column, 43, 44 ... Detection part 45 ... Measurement pH electrode, 46 ... Comparison pH electrode, 47 ... Measurement pH meter, 48 ... Comparison pH meter, 49 ... Calculation processing unit

Claims (11)

  A measurement column and a comparison column of the same volume, which are connected in parallel with each other, pass the treated water discharged from the outlet side of the water treatment unit, and are arranged on the downstream side in the water movement direction of the measurement column. Based on the measurement water quality measuring device, the comparison water quality measuring device disposed downstream of the comparison column in the water movement direction, the measurement value by the measurement water quality measurement device, and the comparison value by the comparison water quality measurement device And a calculation means for calculating the degree of water quality abnormality.   The measurement column is filled with an inert packing material, and the comparison column is filled with an active packing material. Item 1. A water quality abnormality detection apparatus according to Item 1.   The packing active for the test object is a cation exchange resin, an anion exchange resin, a mixed bed ion exchange resin in which a cation exchange resin and an anion exchange resin are mixed at an arbitrary ratio, sand for filtration, or activated carbon. The water quality abnormality detection device according to claim 2.   The water quality abnormality detection device according to claim 2 or 3, wherein the filler inert to the inspection object is a glass bead.   The water quality abnormality detection device according to any one of claims 1 to 4, wherein the measurement column and the comparison column have the same porosity.   2. The measuring water quality measuring instrument and the comparative water quality measuring instrument are at least one measuring instrument selected from a turbidimeter, a chlorine meter, a pH meter, a conductivity meter, and a resistivity meter. The water quality abnormality detection apparatus of any one of thru | or 5.   The water quality abnormality detection device according to any one of claims 1 to 6, wherein the calculation means has a function of notifying when the degree of the water quality abnormality becomes a predetermined value.   A water treatment unit, a measurement column and a comparison column of the same volume connected in parallel to each other at the outlet side of the water treatment unit, and a water quality for measurement disposed on the downstream side in the water movement direction of the measurement column Water quality abnormality based on a measuring device, a comparative water quality measuring device disposed downstream of the comparison column in the direction of water movement, a comparison value by the measuring water quality measuring device, and a comparative value by the comparative water quality measuring device A water treatment apparatus comprising: an arithmetic means for calculating the degree of the water.   The water treatment apparatus according to claim 8, wherein the water treatment apparatus is a pure water production apparatus or an ultrapure water production apparatus.   Treated water discharged from the water treatment unit is passed through the measurement column and the comparison column of the same volume connected in parallel, and the quality of the treated water is measured after passing through the measurement column. Measuring the water quality of the treated water after passing through the comparison column as a measured value, using this as a comparative value, and monitoring the difference between the measured value and the comparative value to calculate the degree of water quality abnormality A characteristic water quality abnormality detection method.   The measurement column is filled with an inert packing material, and the comparison column is filled with an active packing material. Item 11. The water quality abnormality detection method according to Item 10.

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