JPH1094786A - Control method for regenerating softening device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a softening device from being incompletely regenerated by providing a raw water pressure detector for detecting the pressure of a raw water in a raw water supply line and outputting it to a controller, and prolonging the time for a reproducing process when the raw water pressure detected in the raw water pressure detector is lower than a prescribed pressure in the reproduction process. SOLUTION: In the reproduction process of this softening device, the raw water is introduced into a resin column 7 at first and the ion exchange resin is back washed while being stirred. Next, a chemical supplying and pushing-out process is performed by introducing a salt water produced in a salt water vessel 9 into the resin column 7 and ion-exchanging with the ion exchange resin. Finally the salt water in the resin column 7 is discharged and washed. In such a case, when the raw water pressure detected by the raw water pressure detecting device 4 is lower than the setted pressure for the chemical supply and pushing-out process or the setted pressure for washing process in the chemical supply and pushing-out process or the washing process, the control device stops the operation of a timer device 1 for a fixed time and the time for the chemical supply and pushing-out device or the washing process is prolonged by the stopping time of the timer device 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regeneration control method for a softening device for softening water with an ion exchange resin.

[0002]

2. Description of the Related Art A softening device for removing a hardness component using an ion exchange resin is installed in a water supply line to prevent scale from adhering to a water pipe of a boiler or the like. The softening device is to pass the raw water through the ion-exchange resin layer and ion-exchange between the raw water and the ion-exchange resin to take in the hardness component in the raw water into the resin layer. It is necessary to regenerate the resin.

[0003] The time of regeneration is determined by the amount of water taken out of the soft water, the amount of water taken out is calculated from the operating time of the flow meter or the apparatus using the soft water, and the regeneration is performed every time the calculated amount of water taken out reaches the set amount. Regeneration of the ion-exchange resin consists of a backwashing step in which the ion-exchange resin is agitated, a salt-feeding process that sends salt water to the ion-exchange resin layer, and conducts ion exchange to remove the hardness component that the ion-exchange resin has taken up. This is performed in a washing step of discharging the replaced salt water. In each step, an elapsed time is detected by a timer device, and when the elapsed time reaches a set time, the step ends and the next step is performed.

At the time of regeneration, the drug passing / extrusion step is to send the salt water generated in the salt water tank to the resin tower. Usually, the salt water is sucked from the salt water tank using an ejector using raw water as a driving fluid, and the resin is pumped. Inject into the tower. In order to complete the contact between the salt water and the ion exchange resin within the time of the drug passing / extrusion process, the raw water pressure needs to be equal to or higher than a predetermined pressure. Also, in the case of the washing step, since the salt water in the ion exchange resin layer is discharged using the pressure of the raw water, the pressure of the raw water must be high. Therefore, when the raw water pressure decreases during regeneration and the raw water pressure becomes lower than a predetermined pressure, the salt water suction speed of the ejector decreases in the drug passing step, and in the extrusion step, all the salt water injected into the resin tower is discharged. Before the ion-exchange resin is fully contacted, the process shifts to the washing process and the salt water flows out, so the regeneration of the ion-exchange resin becomes incomplete,
A water leak containing a hardness component is taken out, which causes a hardness leak. Also, even if the ion exchange resin is regenerated during the drug passing / extrusion process, if the raw water pressure drops during the washing process, the salt water that could not be completely washed when the softening process was restarted leaked into the treated water. At the same time, a small amount of hardness components also leak into the treated water. Even if it is a rare phenomenon that the raw water pressure decreases, it is necessary to make settings in anticipation that the raw water pressure will decrease in order to prevent hardness leaks. I had to.

[0005]

The problem to be solved by the present invention is that the regeneration step is performed more than necessary while the raw water pressure is in a normal range, or the regeneration is incompletely completed due to a decrease in the raw water pressure. It is an object of the present invention to provide a regeneration control method for a softening device, which can prevent the occurrence of swelling.

[0006]

Means for Solving the Problems A resin tower filled with ion exchange resin in a container, a salt water tank for generating salt water, a control valve for supplying raw water to the resin tower and the salt water tank and taking out treated water, and a control valve A control device is provided to perform control, and the raw water sent from the raw water supply line to the control valve is passed through the ion exchange resin layer in the resin tower to perform softening treatment, and is periodically sent to the ion exchange resin layer in the resin tower. The ion-exchange resin is regenerated by supplying salt water in an appropriate manner.In the regeneration process, the elapsed time is detected by a timer device built into the control device, and when the elapsed time reaches the set time, the regeneration process is terminated. In the softening device, a raw water pressure detecting device for detecting the pressure of the raw water in the raw water supply line and outputting the detected pressure to the control device is provided. If the detected raw water pressure at the pressure sensing device is lower than a predetermined pressure, thereby completely perform reproduction by extending the regeneration step time.

[0007]

An embodiment of the present invention will be described with reference to the drawings.
The softening device comprises a resin tower 7 filled with an ion exchange resin, a control valve 8 for controlling each water flow, a salt water tank 9 for producing salt water, and a control device 10. The tip of the raw water supply line 2 is connected to the control valve 8, and the control device 10 controls the control valve 8 to
The raw water sent through the raw water supply line 2 is sent to the resin tower 7 or the salt water tank 9 through the control valve 8. A raw water pressure detecting device 4 for detecting the pressure of raw water is provided in the raw water supply line 2, and the raw water pressure detected by the raw water pressure detecting device 4 is sent to the control device 10.

When performing the softening treatment, the controller 10 adjusts the control valve 8 so that the raw water is sent to the resin tower 7, and introduces the raw water into the resin tower 7. In the resin tower 7, the hardness component in the raw water is removed by the ion exchange resin, and the treated soft water is sent to the soft water tank 6 through the control valve 8 and the treated water supply line 3. A flow meter 5 is provided in the middle of the treated water supply line 3, and the flow rate detected by the flow meter 5 is sent to the control device 10. The control device 10 integrates the flow rate obtained from the flow meter 5, and regenerates the ion exchange resin when the integrated water sampling amount reaches a set value.

In the regeneration step of the softening device, first, raw water is introduced into the resin tower 7 and backwashing is performed in which the ion exchange resin is stirred. The control device 10 starts the operation of the timer device 1 incorporated in the control device 10 at the same time as the start of the backwashing process, and detects the elapsed time. When the elapsed time detected by the timer device 1 reaches the set time of the backwashing step, the backwashing step is ended.

When the backwashing step is completed, the control device 10 changes the control valve 8, introduces the salt water generated in the salt water tank 9 into the resin tower 7, and causes ion exchange with the ion exchange resin. Perform the drug delivery and extrusion process. At the time of the drug passing / extrusion step, the timer device 1 is operated to detect the elapsed time, and when the elapsed time reaches the set time of the drug passing / extrusion step, the drug passing / extrusion step is terminated. The pressure of raw water is important in the drug passing / extruding step, and the drug passing / extruding step time is adjusted by the raw water pressure detected by the raw water pressure detecting device 4. If the detected raw water pressure is lower than the set pressure for the drug-delivery / extrusion process during the drug-delivery / extrusion process, the control device 10
Stops the operation of the timer device 1 for a certain period of time, and prolongs the time of the drug delivery / extrusion process by the timer device stop time.

[0011] When the drug delivery / extrusion process is completed, the control device 1
At 0, the control valve 8 is changed, and a washing step of discharging the salt water in the resin tower 7 is performed. During the cleaning process, the timer device 1 is operated to detect the elapsed time, and when the elapsed time detected by the timer device 1 reaches the set time of the cleaning process, the cleaning process ends. The raw water pressure is also detected by the raw water pressure detecting device 4 during the cleaning process, and when the detected raw water pressure falls below the set pressure for the cleaning process, the control device 10 stops the operation of the timer device for a certain period of time. In addition, the time of the cleaning process is lengthened by the stop time of the timer device.

In this embodiment, when the pressure of the raw water drops during the drug passing / extrusion step or the washing step, the step is extended for a certain period of time. The process extension time may be converted from the decrease time, and the process time may be extended by the calculated time.

[0013]

According to the present invention, when the raw water pressure is within the normal range, the regeneration step is performed more than necessary, so that more water than necessary is not used.
When the pressure of the raw water drops, the time of the regeneration step is extended to prevent incomplete regeneration.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a softening device embodying an embodiment of the present invention. 1 Timer device 2 Raw water supply line 3 Treated water supply line 4 Raw water pressure detection device 5 Flow meter 6 Soft water tank 7 Resin tower 8 Control valve 9 Salt water tank 10 Control device

Claims (1)

[Claims] 1. A resin tower filled with an ion exchange resin in a container, a salt water tank for generating salt water, a control valve for supplying raw water to the resin tower and the salt water tank and for taking out treated water,
A control device that controls the control valve is provided, and the raw water sent from the raw water supply line to the control valve is passed through the ion exchange resin layer in the resin tower to perform softening treatment, and the ion exchange resin in the resin tower is The ion exchange resin is regenerated by periodically supplying salt water to the bed. In the regeneration process, the elapsed time is detected by a timer device built in the control device, and when the elapsed time reaches the set time, the regeneration process is performed. In the softening device, the raw water pressure detecting device that detects the pressure of the raw water in the raw water supply line and outputs it to the control device is provided, and the raw water pressure detected by the raw water pressure detecting device during the regeneration process is A regeneration control method for a softening device, wherein the regeneration step is extended when the pressure is lower than a predetermined pressure.