JPH0772115A - Hardness leakage detection method for soft water apparatus - Google Patents

Abstract

PURPOSE:To provide a method which makes it detect hardness leakage of a soft water apparatus simply and accurately, and without labor. CONSTITUTION:Treated water from a soft water apparatus A passes through a container I filled with a chelate resin and changes in the concentrator of hydrogen ions released when a hardness component leaked from the soft water apparatus A is trapped into the chelate resin are measured to detect the hardness leakage. Therefore, since the detection of the hardness leakage is made possible by utilizing the changes in the concentration of the hydrogen ions, higher accuracy is assured. Moreover, since the chelate resin is consumed only when the hard component is leaked from the soft water apparatus to eliminate, labor for the replenishing of chemicals or the like is saved, and hardness leakage can be detected simply at a low cost.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hardness leak detection method for a water softener.

[0002]

2. Description of the Related Art As is well known, in water supply lines for cooling and heating equipment such as boilers, water heaters, coolers, etc., it is necessary to prevent scale from adhering to the inside of the cooling and heating equipment, so that the hardness contained in the water supply is removed. For this purpose, an automatic regenerating type water softener of a type that uses an ion exchange resin to remove hardness is widely used.

This type of water softener generally uses a Na ⁺ type ion exchange resin and contains Ca ²⁺ or M contained in water.
A metal cation such as a ²⁺ is replaced with Na ⁺ to remove the hardness, and when the ion exchange resin becomes saturated due to the above cation substitution and loses the ability to remove the hardness. , Is configured to react with saline and regenerate capacity.

However, even if such a regenerating operation is performed, the hardness component cannot be removed by the water softener due to deterioration of the ion exchange resin itself, insufficient regeneration, etc. It may flow in (so-called hardness leakage).

[0005] Such hardness leaks have been an important monitoring item from the past because they interfere with the safe operation of cooling and heating equipment, and various detection methods have been proposed.

For example, a method of visually detecting hardness leakage by collecting a sample from a soft water supply path of a water softener and adding a hardness indicator, and a hardness sensor using an ion electrode and a reference electrode in the soft water supply path are used. There is a method of connecting and monitoring hardness leak with this hardness sensor.

[0007]

By the way, in the conventional work of detecting hardness leak in a water softener, the method of adding an indicator as described above requires operations such as sampling and addition of an indicator. There is a problem that is complicated and takes time. Further, although an automated operation of this series of work has been proposed, the indicator is expensive, and it is necessary to replenish the indicator periodically, so that it cannot be completely automated.

On the other hand, in the method of detecting hardness leak using one hardness sensor (for example, Ca ²⁺ ion sensor), the accuracy of the sensor itself is poor, and periodical calibration work and replacement work due to performance deterioration are required. In addition, since the work is performed manually, it may be complicated and the work may not always be performed reliably. Therefore, leakage of the hardness component from the water softener cannot be detected, and the hardness component flows into the downstream cooling equipment. Further, it may be possible to automate the above calibration work, but it is difficult to control the standard solution used for the calibration, and the apparatus itself becomes expensive.

[0009]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, in which treated water from a water softener connected in a water supply line is circulated in a container filled with a chelate resin, Hardness leaked to the soft water from the water softener is measured by measuring the change in the concentration of hydrogen ions released when it is collected in the chelate resin, and the hardness leak is detected. This is a method for detecting hardness leaks in containers.

[0010]

According to the present invention, the hardness leak is detected by measuring the change in the concentration of hydrogen ions released when the chelate resin collects the hardness leaked from the water softener.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a concrete embodiment of a hardness leak detecting method for a water softener according to the present invention. In the drawing, (A) shows a water softener, (I) shows a reaction tank containing a chelate resin, and (S) shows a pH measuring device for measuring a change in hydrogen ion concentration as a hydrogen index.

The water softener (A) is of a general type that automatically regenerates on the basis of an integrated value of the amount of water flow. In the illustrated embodiment, the raw water inlet (1) and treated water (soft water) are used. Supply port
It is connected to the water supply line (L) between (2).

From the water softener (A) to the treated water supply port (2)
A first valve (V1) that operates so that the water softener (A) is closed during the regeneration operation is connected in the flow path leading to. or,
The flow path between the water softener (A) and the first valve (V1) is connected to a flow path (3) with a small flow rate for measuring hardness, and this flow path (3) has Second opening during water softening operation of water softener (A)
The valve (V2) of is connected.

The above reaction tank (I) and pH measuring device
(S) is connected to the downstream side of the second valve (V2) in the flow path (3) in this order.

As the chelate resin in the reaction vessel (I), for example, one having an iminodicarboxylic acid group or an aminophosphoric acid group as a functional group is used.

In general, a chelate resin seals a divalent cation as a hardness component, for example, Ca ²⁺ , as shown in the following formula, and releases two hydrogen ions at this time.

[0017]

[Chemical 1]

That is, since there is a certain correlation between the amount of hardness component to be sealed and the amount of hydrogen ions released,
The hardness leak can be measured by measuring the hydrogen ion amount. In this embodiment, the hydrogen ion amount is measured as a hydrogen index.

The first valve (V1) and the second valve
The valves (V2) have the following functions, respectively. That is, the first valve (V1) has a state in which the raw water inlet and the treated water outlet communicate with each other during the regenerating operation of the water softener (A), and the raw water remains untreated and the treated water supply port (2 ), The second valve (V2) on the one hand is the same as the first valve (V1), and the water softener at the time of regeneration is used.
This is to prevent the raw water from (A) from flowing into the reaction tank (I) and the pH measuring device (S) and open the flow path to the reaction tank (I) only when measuring the hardness of the treated water. .

Further, the reason why the flow path for hardness measurement (3) is made to have a small flow rate is that a small amount of water is sufficient for detecting the hardness leak, as described later.

The procedure for detecting hardness leakage in the present invention will be described below. First, the raw water from the raw water inlet (1)
Water softening treatment by water softener (A), treated water supply port (2)
Is supplied as soft water to a cooling / heating device or the like (not shown).
At this time, since both the first and second valves (V1) (V2) are open, a part of the treated water from the water softener (A) described above flows into the hardness measurement flow path (3). It flows into the reaction tank (I).

When the treated water contains a hardness component, in the reaction layer (I), the action of the chelate resin causes the hardness component to be collected by the functional groups of the chelate resin, and an amount of hydrogen proportional to the hardness component is collected. Emits ions. Therefore, this reaction layer
The treated water in (I) has an increased hydrogen ion concentration, that is, p
The H value has dropped, and in this state the downstream pH measuring device
This pH value is measured by (S). If this pH value is lower than the normal soft water state, it can be seen that the hardness is leaking.

Here, assuming that the pH value of the treated water in the case where water is softened normally is 7 and Ca ²⁺ leaks into this treated water as a hardness component of 1 ppm, the hydrogen ion H ⁺ is 1.0. Due to the release of × 10 ^-3 mol / L, the pH value drops to 4. Therefore, by detecting the change in the pH value, the hardness leak can be detected accurately and easily, and the amount of the sample for measuring the pH value can be extremely small.

Further, since the release of hydrogen ions from the chelate resin occurs only when hardness leakage occurs, the reaction layer
Consumption of the chelate resin in (I) is very small and it is semi-permanent, which eliminates the need for conventional replenishment of chemicals.

During the regenerating operation of the water softener (A), the first and second valves (V1) (V2) are switched to the closed state so that the raw water or the like can be used for cooling or heating equipment.
Reaction layer (I) in hardness measurement channel (3), pH measuring device (S)
Prevent it from flowing into.

[0026]

According to the hardness leak detection method for a water softener according to the present invention, by measuring the change in the concentration of hydrogen ions released by adsorbing and sealing the hardness component with a chelate resin, it is possible to obtain an extremely high accuracy. Good and accurate hardness can be measured, and hardness leak can be detected reliably.

Furthermore, in the method of the present invention, the release of hydrogen ions from the chelate resin is only when hardness leakage occurs, so the consumption of the chelate resin is very small and it is semi-permanent. No need for regular replenishment, etc., and hardness leak detection can be performed easily and inexpensively.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a hardness leak detection method for a water softener according to the present invention.

[Explanation of symbols]

 (1) Raw water inlet (2) Treated water inlet (3) Hardness measurement flow path (A) Water softener (I) Reaction tank (L) Water supply line (S) pH measuring device (V1) First valve ( V2) Second valve

Claims (1)

[Claims] 1. Treated water from a water softener connected to a water supply line is circulated in a container filled with a chelate resin, and the hardness leaked to the soft water from the water softener is collected in the chelate resin. A hardness leak detection method for a water softener, wherein hardness leak is detected by measuring a change in concentration of hydrogen ions released at that time.