JPH0366021B2 - - Google Patents

Description

[Detailed description of the invention] The present invention performs ion exchange treatment by passing liquid in an upward flow through an ion exchange resin bed in a tank, and passes a regenerated liquid in a downward flow through an ion exchange resin bed whose capacity has decreased. The present invention relates to a countercurrent regeneration type ion exchange device that performs regeneration. below,
The superordinate concept of liquid involved in ion exchange processing is sometimes explained as the subordinate concept of water.

In this type of ion exchange equipment, the upper part of the ion exchange resin bed is well regenerated by downward flow regeneration, and the upper part, which first encounters new regenerated liquid, is completely regenerated, and this upper part is treated when the water flows upward. Since this is the outflow end of water, highly purified treated water can be obtained. Therefore, there is an advantage that it is not necessary to use a large amount of regenerant liquid to increase the regeneration level in order to obtain treated water of the desired high purity. However, when water flows upward, the ion exchange resin tends to rise and become fluidized, and as a conventional measure to prevent this fluidization, a treated water collector is buried near the top of the ion exchange resin bed, and then Fluidization is suppressed by placing excess ion exchange resin or other fillers on top of the tank, or by passing treated water in a downward flow from the top of the tank. These measures have drawbacks such as a decrease in the utilization efficiency of the ion exchange resin and wasteful power consumption due to the downward flow.

The present invention has been made to solve the above problem, and the interior of the ion exchange tank is divided into an upper chamber and a lower chamber through a partition wall provided with a large number of communicating holes distributed. is filled with ion exchange resin to form a bed, and each communication hole is equipped with a float valve.In particular, this float valve closes during upward flow ion exchange processing to prevent the ion exchange resin from moving upward, but the bed During upward flow cleaning of accumulated pollutants, it opens to allow the ion exchange resin to move from the lower chamber to the upper chamber, and is opened by the downward flow to allow the return of the ion exchange resin that has migrated to the upper chamber. It is configured to exhibit various switching functions to perform downward flow regeneration of the floor.

To achieve this objective, the countercurrent regeneration type ion exchange apparatus of the present invention has a structure in which the liquid to be treated is passed in an upward flow through a bed of granular ion exchange resin formed at the bottom of a vertical closed tank. In the countercurrent regeneration type ion exchange treatment method, in which regeneration is carried out by passing the regeneration liquid in a downward flow through the ion exchange resin bed whose treatment capacity has decreased, communication holes are distributed in the tank. A treated water collector is installed along the bottom surface of the partition wall, and a float valve is installed in each communication hole, and the float valve has a float smaller in diameter than the inner diameter inside the valve cylinder. In addition, liquid-permeable holding frames are provided above and below inside the valve cylinder to restrain the float in the raised and lowered positions, and an annular structure that can be elastically brought into close contact with the float valve in the raised position restrained by the upper holding frame from above. It is characterized by being formed by providing a valve seat.

Hereinafter, the present invention will be explained specifically and in detail with reference to embodiments shown in the accompanying drawings.

In the apparatus of the present invention shown in FIG. 1, an ion exchange treatment tank 1 is of a vertically long closed type and has an upper nozzle 2, a lower nozzle 3, and a side nozzle 4 for external connection. The upper nozzle 2 serves as an inlet for regenerating agent liquid and an outlet for cleaning wastewater, the lower nozzle 3 serves as an inlet for raw water and washing water, and an outlet for regenerating wastewater, and the side nozzle 4 serves as a processing outlet.

The interior of the tank 1 is divided into an upper chamber 6 and a lower chamber 7 by a horizontally transverse partition wall 5 of intermediate height, and the partition wall 5 is provided with a number of communicating holes 8 for mounting a float valve, which will be described later, in a distributed manner. A water collector 9 connected to the side nozzle 4 is provided in the lower chamber 7 along the lower surface of the partition wall 5, and a support plate 11 on which strainers 10 are distributed is provided at the bottom of the tank. An ion exchange resin bed 12 is formed by filling an amount of granular ion exchange resin that almost fills the space between the support plate 11 and the support plate 11 .

A float valve 13 is attached to each communication hole 8 of the partition wall 5. FIG. 2 shows one float valve 13 in detail. Inside the valve cylinder 15, which has the lower holding frame 14 integrally formed at its lower end, there is a float 16, which is spherical in this example, has a smaller diameter than the inner diameter of the valve cylinder 15, and moves up and down with the liquid flow.
to accommodate. The specific gravity of the float 16 is approximately 1.
An upper holding frame 17 is placed on the upper edge of the valve cylinder 15, and a flexible valve seat 18 in the form of an annular plate made of an elastic material is placed thereon and fixed by screwing into the holding cylinder 19. The float valve 13 is attached to the partition wall 5 by inserting the holding cylinder 19 into the communication hole 8 and applying a nut 20. If the partition wall 5 is made of synthetic resin, it may be directly screwed into each communication hole 8 and fixed so that there is no protrusion on the partition wall 5.

The upper holding frame 17 has four radial arms 17b extending inward from its outer ring 17a to the middle, and its inner end span S is formed to be smaller than the diameter of the float 16. In this way, the float 16 is restrained in the raised position with its upper part partially protruding from the center of the upper holding frame 17, and in this state, the upper holding frame 17
It communicates vertically in the space between the arms 17b and maintains fluid permeability.

When the upward flow velocity is below a certain level, the annular valve seat 18 comes into close contact with the upper part of the float 16, which is restrained in the raised position, from above due to its elasticity, and the circular opening 18a at the center thereof is closed. For an upward flow velocity above a certain level, as shown in FIG.
a is separated from the float 16 and opens.

The lower holding frame 14 is formed in the same manner as the upper holding frame 17, and as shown in FIG. 4, suppresses the float 16 that has descended to the lowered position due to the downward flow and maintains liquid permeability.

The apparatus according to the present invention having the above configuration is operated as follows.

() Normal ion exchange treatment operation: Close the upper nozzle 2, open the side nozzle 4,
The lower nozzle 3 is opened to feed raw water to be treated into the tank. The raw water is subjected to ion exchange treatment while passing through the ion exchange resin bed 12 in an upward flow, becomes treated water, is collected in the water collector 9, and is sent out from the side nozzle 4.

During this time, the water pressure above and below the partition wall 5 is balanced due to the closure of the lower nozzle 2, so no upward flow from the lower chamber 7 to the upper chamber 6 occurs. An upward force is exerted on the ion exchange resin in the lower chamber 7 by the upwardly flowing water, and this force acts on the valve seat 18 from the space between the arms 17b of the upper holding frame 17. However, since the valve seat 18 has enough elasticity to not separate from the float 16 as shown in FIG. held tightly.

() Regeneration and cleaning operations When the exchange capacity of the ion exchange resin is consumed due to continuous water flow treatment and the treatment function deteriorates, the water flow is stopped, the side nozzle 4 is closed, and the lower nozzle 3 is opened toward the discharge system. The regenerant liquid is supplied from the upper nozzle 2. As shown in Fig. 4, the regenerated liquid pushes down the float 16 of the float valve 13 by a downward flow, flows into the lower chamber 7, passes through the ion exchange resin bed 12 in a downward flow, and is regenerated, and the regenerated liquid is discharged to the lower part. It is discharged from the nozzle 3. After the regeneration is completed, the ion exchange resin bed 12 is washed by flowing the washing water in a downward flow through the same route to extrude the regenerated liquid. After completing the regeneration cleaning operation, return to the operation in ().

Note that the regeneration operation can also be carried out by draining the water in the upper chamber 6 and supplying the regeneration liquid from the side nozzle 4 after the water flow process is stopped.

() Pollutant washing and discharging operation By repeating the water flow treatment operation, the suspended matter contained in the raw water is filtered and gradually accumulates in the ion exchange resin bed 12, so in this case, the ion exchange treatment is not performed. It is necessary to stop the process, clean the ion exchange resin bed 12, remove pollutants, and discharge it together with the cleaning waste water. This operation is performed by closing the side nozzle 4, opening the upward nozzle 2 toward the discharge system, and supplying cleaning water from the lower nozzle 3. The water that has passed through the ion exchange resin bed 12 in an upward flow cannot flow to the side nozzle 4 and instead goes to the upper nozzle 2, so the float valve 1
3 as shown in FIG. 3, and the valve seat 18 is pushed up by this upward flow and opened away from the float. As a result, the ion exchange resin in the lower chamber 7 becomes fluidized, and a portion of it moves to the upper chamber 6 through the float valve 13 and spreads in both chambers at the same rate, thereby effectively cleaning and removing pollutants. be able to.

After the cleaning is completed, the upward flow is stopped and water is passed downward from the upper nozzle 2, and the float 16 descends as shown in Fig. 4, and the ion exchange resin in the upper chamber 6 is transferred to the lower chamber with the downward flow. Return to step 7 and return to ion exchange resin bed 1
2 is formed. By attaching the float valve 13 so that there is no protrusion on the partition wall 5 and smoothing the upper surface as described above, the amount of ion exchange resin remaining in the upper chamber 6 when returning the ion exchange resin to the lower chamber can be minimized. It can be done.

As described above, according to the present invention, when the ion exchange resin bed is filled in the lower part of the tank and ion exchange treatment is performed in an upward flow, the ion exchange resin bed can be suppressed and tightly held in the lower chamber. The upper chamber can be used to effectively wash and discharge accumulated foreign matter in the ion exchange resin bed by upward flow. Moreover, since the float valve of the present invention functions both as an upward flow valve and a downward flow valve, the number of communication holes and valves in the partition wall can be reduced to about half, and the manufacturing cost can be reduced. There are various effects such as.

[Brief explanation of drawings]

FIG. 1 is a vertical side view of an ion exchange device according to an embodiment of the present invention, FIG. 2 is a vertical side view showing the float valve of the float raised and the valve seat closed, and FIG.
FIG. 4 is a longitudinal side view showing the float valve in a raised and valve seat open state, FIG. 4 is a longitudinal side view showing the float in a lowered state, and FIG. 5 is a plan view of the upper holding frame. 1... Ion exchange treatment tank, 2... Upper nozzle,
3... Lower nozzle, 4... Side nozzle, 5... Partition wall, 6... Upper chamber, 7... Lower chamber, 8... Communication hole, 9... Water collector, 10... Strainer, 11...
...Support plate, 12...Ion exchange resin bed, 13...
Float valve, 14... Lower holding frame, 15... Valve cylinder, 16... Float, 17... Upper holding frame, 1
7a... Outer ring, 17b... Arm, 18... Valve seat, 18a... Center opening, 19... Holding cylinder, 20
...Natsuto.

Claims (1)

[Claims] 1. Ion exchange treatment is carried out by passing the liquid to be treated in an upward flow through a bed of granular ion exchange resin formed at the bottom of a vertical closed tank, and the regenerated liquid is thus transferred to the ion exchange resin bed whose processing capacity has decreased. In the countercurrent regeneration type ion exchange treatment method, which regenerates water by flowing it in a downward flow, the inside of the tank is divided into upper and lower sections by partition walls with communicating holes distributed in a distribution manner, and the treated water is collected along the bottom surface of the partition wall. A float valve is installed in each communication hole, and the float valve has a float smaller in diameter than the inner diameter of the valve cylinder, and has liquid permeability that prevents the upper and lower floats of the valve cylinder from rising and falling. 1. A countercurrent regeneration type ion exchange device comprising a holding frame and an annular valve seat that can elastically come into contact with a float in a raised position restrained by an upper holding frame from above.