JPH0125629Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a collection and water sprinkling device that doubles as a filler support mechanism and is installed on the lower head plate of an ion exchange tower. The water head loss is not too large, and it is not blocked by scale or foreign matter, and it is possible to obtain a uniform watering effect when watering in an upward flow for backwashing etc. It is.

FIG. 1 shows an ion exchange tower, and a water collecting and sprinkling device 2 is provided on the mirror section 1 at the lower end of the tower. As shown in a partially enlarged view of FIG. 2, the conventional water collection and distribution device has holes 4' and 5' whose diameter is considerably larger than the particle size of the ion exchange resin of the packed bed 3 supported above. A mesh material 6, for example Sarannet, whose mesh 6' is smaller than the particle size of the ion exchange resin is sandwiched between the upper perforated plate 4 and the lower perforated plate 5, which have a large number, and the holes 4' and 5' of the upper and lower perforated plates are aligned in the vertical direction. It is installed. However, with this, due to the large opening ratio of the mesh material exposed in the large holes 4' and 5' of the upper and lower perforated plates, there is less water head loss when collecting water by flowing the treated water in a downward flow, and the power cost is also reduced. It also prevents blockages, but when water is passed in an upward flow for backwashing, etc., the large opening ratio causes uneven flow, resulting in extremely poor uniform watering performance, and even when backwashing, ion If the replacement resin does not restore performance sufficiently,
Even if recovery occurs, it takes a very long time and requires a huge amount of backwash water. Therefore, if the hole diameter of the upper and lower perforated plates is made smaller and the aperture ratio is made smaller, the water head loss will increase when water is collected, and
The holes and meshes are easily clogged with foreign matter, and in the worst case, there is a risk of destruction.

In addition, there is an example in which a baffle 8 is provided above the backwash water inlet (which also serves as the treated water outlet when collecting water) 7 in order to prevent drifting as much as possible, but this is not sufficient. In particular, in order to restore the performance of the resin, ion exchange towers have higher requirements for uniform water sprinkling performance during water sprinkling for backwashing than filter towers and other treatment towers.

Therefore, in the present invention, the upper perforated plate 4 and the middle mesh material 6 are the same as before, but the diameter of the holes in the lower perforated plate is made smaller than that of the upper perforated plate, which allows the treated water to flow downward. Although the head loss increases slightly when water is used, water can be sprayed evenly throughout the tower during backwashing.

Figures 3 and 4 show parts of the water collection and distribution device of the present invention, in which the holes 4' of the upper perforated plate 4 are considerably larger than the particle size of the ion exchange resin as in the conventional case, and the holes 4' are made of a mesh. Although the mesh 6' of the material 6 is smaller than the particle size of the ion exchange resin, the diameter D of the holes in the lower perforated plate 9, which are arranged in the same way as the holes in the upper perforated plate and are aligned in the vertical direction, is smaller than that of the upper perforated plate.

Normally, the particle size of ion exchange resin is about 0.3 to 1.2 mm, so the diameter of the holes 4' in the upper perforated plate is about 20 mm.
The mesh 6' of the mesh material is a square with each side of about 0.2 mm, whereas the hole diameter D of the lower perforated plate of the present invention is about 4 mm.

Preferably, the diameter of the holes in the lower perforated plate 9 on the lower surface of the plate is small as described above, and on the upper surface of the plate, the diameter is the same as or larger than that of the holes 4' in the upper perforated plate 4. Therefore, the increase in water head loss during collection when the treated water is passed in a downward flow is minimized. Therefore, in the embodiment shown in FIG. 3, the holes in the lower perforated plate have a cylindrical portion 8a having the same diameter as the hole in the upper perforated plate from the upper surface of the plate to the middle, a tapered portion 8b whose diameter decreases downward, and a tapered portion 8b below which has the same diameter as the hole in the upper perforated plate. The center of the portion 8b has a small diameter cylindrical portion 8c with a diameter D open to the lower surface of the plate, and the hole in the embodiment shown in FIG. It consists of a tapered portion 8d with a diameter of D.

As a result, when collecting treated water, the head loss is slightly higher than when the holes in the lower perforated plate have the same diameter as the upper perforated plate, but no blockage occurs, and when water is sprinkled during backwashing. Backwash water is spouted upwards evenly from the entire surface of the water collector into the packed bed of ion exchange resin supported on the water collector and sprinkler from the small diameter part of the hole of the lower perforated plate, and the packed bed is Wash evenly to restore the performance of the ion exchange resin. The reason why water can be collected with only a slight increase in water head loss is that the holes 4' in the upper perforated plate are as large as before, and the holes in the lower perforated plate have a tapered portion 8b whose diameter decreases downward.
8d, which is large on the top surface of the plate and small on the bottom surface of the plate, so the head loss is not affected as much as when all the hole diameters are made small. As in this example, if the diameter of hole 4' in the upper perforated plate is 20 mm and the diameter of the hole in the lower perforated plate is 4 mm, the flow velocity at hole D is calculated to be 0.5 m/sec, and the pressure loss due to contraction and diffusion. This is about 0.023mmAg, and the increase in differential pressure is only minute.In fact, it can be said that the number of water collection holes drilled throughout the water collection and distribution plate has a greater influence on water head loss than the diameter of hole D. .

In addition, when the ion exchange resin packed bed is a mixed bed type, the cation exchange resin and anion exchange resin can be completely separated, and as a result, the amount of regeneration agent and backwashing water used can be saved. It is possible to improve the purity of purified water when obtaining treated water.

In this way, the present invention satisfies the requirements for protection during both water collection and water sprinkling, and has various features such as simple structure, any material can be selected, and easy manufacturing and processing. Water equipment can be provided. It should be noted that if the holes in the upper and lower perforated plates are aligned, the holes can be made at the same time on the upper and lower sides during processing, so they can be manufactured at a lower cost, but it is not always necessary to align the holes.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of the ion exchange tower, Figure 2 is an enlarged cross-sectional view of a part of the conventional water collector and sprinkler used in the above, and Figure 3 is an example of an embodiment of the water collector and sprinkler according to the present invention. FIG. 4 is an enlarged sectional view of a part of the water collection and distribution device according to another embodiment of the present invention, in which 4 is the upper perforated plate, 4' is the hole thereof, and 6 is the mesh. 6' indicates the mesh, 9 indicates the lower perforated plate, and D indicates the diameter of the hole.

Claims (1)

[Scope of Claim for Utility Model Registration] In a water collection and distribution device for an ion exchange tower in which a mesh material having a mesh size smaller than the particle size of the packed bed supported above is sandwiched between upper and lower perforated plates, the holes in the upper perforated plate are larger than the particle size of the packed bed,
Further, the hole in the lower perforated plate is provided with a tapered part whose diameter decreases downward, and the diameter at the upper surface of the hole is made equal to or larger than that of the hole in the upper perforated plate,
A water collection and distribution device for an ion exchange tower, characterized in that the diameter at the bottom surface is smaller than the pores in the upper perforated plate.