JPH03211302A - Device to prevent resin in supply water filtering tower from falling - Google Patents

Abstract

PURPOSE:To make small the backflow of the supply water to a filtering tower and the propagaged vibration and prevent the resin in a filtering tower from falling by suppressing the pressure vibration in the supply water in a supply water system during tripping in all the pumps due to power failure. CONSTITUTION:The supply water the pressure of which is boosted by a pump is filtered by a resin 13 in a filtering tower 1, and its flow rate is controlled by a tower flow rate control valve 3 and flows to the downstream. During the normal stopping of a supply water system in order to press the resin 13 on to the inner wall of the filtering tower the pressure of the supply water branched from the outlet of the filtering tower 1 is boosted by a holding pump and the supply water is returned to the inlet of the filtering tower 1 to be recirculated and the resin 13 is pressed on to the inner wall of the filtering tower. The pressure vibration that is developed by the pump trip in the supply water system caused by power failure for the supply water system and propagaged to the side of the filtering tower 1 is damped by the volume of the inside of a surging tank 14, and, further, the vibration is blocked by a check valve 15 provided between the filtering tower 1 and the surge tank 14. With this arrangement the backflow of the supply water to the inside of the filtering tower 1 is suppressed and at the same time the stress worked on a filter flow rate adjusting valve 3 is eased and it is possible to prevent the resin from falling.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a water supply filtration device, and particularly to a water supply device in which the water supply filtration device is incorporated, which can be used to prevent sudden changes in pressure within the water supply device due to loss of pump driving power, etc. Vibration) This invention relates to a resin fall prevention device for a water supply filtration device filtration tower suitable for measures against resin fall in a water supply filtration tower during backflow.

[Conventional technology]

As described in Japanese Patent Publication No. 59-12923, in order to prevent a decrease in water supply due to a delay in the operation of the filtration tower flow rate adjustment valve in an abnormal situation, the position of the filtration tower flow rate adjustment valve is locked or forced. I was in between.

However, during the assumption of an abnormality, pressure vibrations in the feed water that occur when all pumps stop due to a power loss accident, which is a single failure mode, and resin drop due to backflow of the feed water into the filtration tower due to pressure vibrations. was not taken into consideration.

[Problem to be solved by the invention]

The above conventional technology does not take into account the propagation of transient pressure vibrations in the water supply system into the filtration tower that occur due to pump trips in the water supply system. It was not possible to prevent the occurrence of pressure vibrations in the internal water supply and the fall of the resin due to the backflow of the water supply into the filtration tower due to the pressure vibrations.

The purpose of the present invention is to suppress the pressure vibration of the feed water in the water supply system when all the pumps trip due to a power loss, thereby reducing the backflow of the feed water into the filtration tower and the propagating vibration, and preventing the resin in the filtration tower from falling. [Means for solving the problem] In order to achieve the above purpose, a surge tank is provided on the outlet side of the filtration tower to damp vibrations of the water supply in the water supply system.
A check valve is installed between this surge tank and the filtration tower flow rate adjustment valve to suppress the propagation of pressure vibrations in the water supply system into the filtration tower when the water supply pump trips, and to suppress the backflow of water into the filtration tower. This is what I did.

[Effect]

Pressure vibrations caused by tripping of all water supply pumps are
It propagates to the surge tank provided on the outlet side of the filtration tower, is attenuated by the internal volume of the surge tank, and is blocked by a check valve.

This suppresses the backflow of the feed water into the filtration tower due to the pressure vibration of the feed water that occurs during the transition of the water feed pump trip due to the power loss signal of the water feed pump, thereby preventing the resin from falling.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG.

The feed water pressurized by the pump is filtered by the resin 13 in the filtration tower 1, and the flow rate is controlled by the bath flow rate regulating valve 3 and flows downstream. When the water supply system is normally stopped, apply resin 13 to the inner wall of the tower.
In order to do this, the water supply branched from the outlet of the filtration tower 1 is pressurized by a holding pump, returned to the inlet of the filtration tower 1, and recirculated to press the resin 13 against the inner wall of the filtration tower.

To control the bath flow rate regulating valve 3, a control signal calculated by a control calculator 4 is transmitted to an electro-pneumatic converter 5, and the electro-pneumatic converter 5 converts the control signal into an air signal 11. air signal 11
passes through the lock valve 6 and is supplied to the bath flow rate adjustment valve 3.

The lock valve 6 cuts off the air signal 11 in response to the lock signal 9, and maintains the opening degree of the bath flow rate regulating valve 3 at that position.

The relationship between the control air pressure and the valve opening of the bath flow rate regulating valve 3 is as follows:
As shown in the figure. Pressure vibration propagating to the filtration tower 1 side, which is generated by a water supply system pump trip due to power loss in the water supply system, is attenuated by the volume inside the surge tank 14. Check valve 1
5 prevents it. This suppresses the backflow of the water supply into the filter tower 1 and also relieves the stress on the bath flow rate regulating valve 3.

According to this embodiment, when the power is lost, the bath flow rate regulating valve 3 can effectively suppress the pressure fluctuation of the feed water in the water supply system during the transition from the open state to the fully closed state, and the flow rate adjustment valve 3 can effectively suppress the pressure fluctuation of the feed water in the water supply system during the transition from the open state to the fully closed state, and It is possible to prevent the backflow of water supply and the fall of resin.

〔Effect of the invention〕

According to the present invention, it is possible to suppress the backflow of water into the filtration tower due to the vibration of the water supply pressure when the water supply system pump trips due to power loss, and to prevent the resin from falling.

Additionally, these improvements can be expected to have the effect of alleviating the stress placed on the regulating valve.

[Brief explanation of drawings]

Fig. 1 is a system diagram of a flow control device for a feed water filtration device according to an embodiment of the present invention, Fig. 2 is a system diagram of a flow control device for a feed water filtration device of Jumaru, and Fig. 3 is a system diagram of a flow control device for a feed water filtration device according to an embodiment of the present invention. It is a relationship diagram. 1...filtration tower, 2...holding pump, 3.
...Bath flow rate adjustment valve, 4...Control calculator, 5...Electro-pneumatic converter, 6...Lock valve, 9...Lock signal, 11
...Air signal, Fig. 1 Fig.

Claims (1)

[Claims] 1. In a water supply system in which a water supply system is provided with a water filtration device equipped with a filtration tower that filters the water supply and a control valve that adjusts the flow rate passing through the filtration tower, a filtration tower outlet (
1. A resin drop prevention device for a water supply filtration tower, characterized in that a surge tank suppresses pressure vibrations from the (downstream) side, and a check valve is provided between the surge tank and the control valve.