JPS583755B2 - water treatment equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a water treatment device having an adsorption layer such as activated carbon, and more specifically, to a water treatment device configured so that an adsorbent such as activated carbon can be replaced economically and in a short time. It is related to the device.

In the following, a conventional device and an embodiment of the present invention will be described using activated carbon as an adsorbent.

Figure 1 is a longitudinal cross-sectional view showing the configuration of a conventional activated carbon adsorption tank.
1 is the tank body, 2 is a supporting bed, 3 is a large number of small diameter through holes provided in the supporting bed 2, 4 is an activated carbon layer deposited on the supporting bed 2, and 5 is an injection port into which water to be treated is injected. The hole, 6 is an on-off valve, and 7 is a water supply/drainage hole that opens on the bottom surface of the activated carbon tank 1. The treated water that has flowed down the activated carbon layer 4 is drained through a drain pipe 7a, an on-off valve 8, and an on-off valve 9 during backwashing. Backwash water is supplied from the water supply and drainage hole 7 through the water supply pipe 7b.

10 is an overflow hole through which backwash water overflows, 11 is an on-off valve thereof,
12 is a manhole for replacing activated carbon, and 13 is a water surface of injected treated water or backwash water.

The activated carbon adsorption tank configured in this way has on-off valves 9 and 11.
is closed, on-off valves 6 and 8 are opened, and water to be treated is injected from arrow A and drained from arrow B. This is what is called a downward flow type.

As this activated carbon adsorption tank is used, it becomes contaminated sequentially from the top layer of the activated carbon layer 4, and when it becomes contaminated to a certain depth, the removal rate of pollutants in the discharged treated water decreases and it becomes unusable. needs to be replaced.

In conventional activated carbon adsorption tanks, after switching the injection of water to be treated to a spare activated carbon adsorption tank, the activated carbon is removed by either opening the manhole 12 and taking out the activated carbon manually, or using a suction pump to suck out the activated carbon together with water in the form of a slurry. After removing all of the activated carbon, it was refilled with new activated carbon and used as a spare for the next changeover, and the activated carbon that was removed was recycled.

In this way, conventional activated carbon adsorption tanks require a lot of effort and time to replace the activated carbon, and therefore require a spare machine.Furthermore, with the contaminated activated carbon in the upper part, the degree of contamination is low, and there is still a need to update it. There are many uneconomical and irrational drawbacks, such as the fact that activated carbon that is not already activated is taken out, which requires wasteful costs for recycling the activated carbon.

Renewal of activated carbon can be carried out by continuously removing activated carbon from the upper layer, which is highly contaminated, in small amounts at high frequency, and at the same time,
It would be ideal if new activated carbon could be filled in the lower layer.

If this could be done, the activated carbon that would be taken out would be only contaminated activated carbon, and the treated water would always pass through the new activated carbon at the bottom of the activated carbon layer, so there would be no uneconomical need to take out activated carbon that is less contaminated, and the treated water would be removed. The water quality is always constant.

In the case of an upflow activated carbon adsorption tank, the water to be treated enters from the bottom of the tank and the treated water comes out at the top, but in this case, the highly contaminated area is at the bottom of the activated carbon layer, so the water to be treated is It is relatively easy to remove only the contaminated activated carbon at the bottom by discharging it along with water from the introduction hole.

Additionally, new activated carbon can be easily introduced from the top.

Therefore, in an upflow type activated carbon adsorption tank, it is possible to take out and fill small quantities at high frequency, and it appears to be close to ideal, but because of the upflow, it has the following drawbacks.

That is, the activated carbon becomes suspended due to the upward flow of the water to be treated, and suspended substances in the water to be treated are not removed.

In addition, since it is in a suspended state and has high fluidity, the activated carbon in the upper and lower layers easily mix during use, and the activated carbon taken out from the lower layer eventually contains uncontaminated activated carbon. Contaminated activated carbon is also mixed in the filled upper layer, which is unsatisfactory.

On the other hand, in the downward flow type, there is no floating state and no flow occurs.

Therefore, an ideal activated carbon adsorption tank can be obtained by filling the activated carbon layer with new activated carbon from the bottom and removing contaminated old activated carbon from the top.

The reason why such an activated carbon adsorption tank has not been realized in the past is that no new method has been found for filling the lower part of the activated carbon layer with activated carbon.

Note that the contaminated activated carbon in the upper part can be easily removed and collected by discharging it from the overflow hole 10 together with the backwash water and the water injected from the lower part for filling the activated carbon.

The present invention has discovered a new method of filling the lower part of the activated carbon layer with new activated carbon, thereby eliminating the drawbacks of the conventional method and providing a nearly ideal device.

FIG. 2 is a longitudinal sectional view of an embodiment of the present invention, in which 14 is a partition plate that divides the activated carbon layer into an upper activated carbon layer 41 and a lower activated carbon layer 42, 15 is a through hole provided in the partition plate 14, and 16 is a partition plate that divides the activated carbon layer into two parts. This is a water supply hole through which water is supplied by stirring the inside of the lower activated carbon layer 42 with a water flow, and in this embodiment, it also serves as a supply hole through which new activated carbon is supplied in the form of a slurry.

Further, in this embodiment, the overflow hole 10 is configured to open near the upper surface of the upper activated carbon layer 41, so that the contaminated activated carbon in the upper layer can be discharged together with the overflow water.

Hereinafter, the procedure for filling the activated adsorption tank according to the present invention with new activated carbon to form the lower activated carbon layer 42 and the functions of each part will be explained.

First, as a first operation, the activated carbon in the lower activated carbon layer 42 is transferred to the lower layer of the upper activated carbon layer 41 through the through holes 15 of the partition plate 14.

The operation in this case is as follows.

(a) Close the on-off valves 6 and 8.

(Port) Open the on-off valves 9, 11, 17, supply a large amount of water from the water supply pipe 7b and also from the water supply hole 16, and set the flow rate of water flowing through the through hole 15 of the partition plate 14 in the range of 80 to 250 m/Hr. Set within.

In this way, the activated carbon in the portion of the lower activated carbon layer 42 near the through hole 15 passes through the through hole 15 together with the flowing water and moves to the lowest layer of the upper activated carbon layer 41.

The activated carbon forming the lower activated carbon layer 42 is removed from the water supply hole 16.
Since the activated carbon approaches the through holes 15 and is stirred by the water flow injected from the activated carbon layer 15, the activated carbon approaches the through holes 15 and is successively sucked into the through holes 15, and finally the entire amount transfers to the upper activated carbon layer 41.

In this case, the water flowing inside the upper activated carbon layer 41 is
The flow is rectified by the through holes 15, and the flow rate is slowed down, so the activated carbon in the layer does not become floating, but since the solidified carbon was loosened by the pressing force when the water to be treated was flowing down, Activated carbon in the lower activated carbon layer 42 can not be prevented from moving into the upper activated carbon layer 41 through the through holes 15 (c) Next, reduce the amount of water supplied from the water supply pipe 7b, and add an appropriate amount of water from the water supply hole 16. At the same time, a new type of activated carbon made into a slurry is delivered.

In this case, the flow rate of water flowing through the through holes 15 of the partition plate 14 is set to 20
If the total water supply amount is adjusted to be within the range of ~50 m/hr, the activated carbon grains will not move up or down through the through holes 15.

Therefore, the activated carbon sent from the water supply hole 16 is transferred to the support bed 2.
The water flowing out from the through holes 3 spreads over the supporting floor surface, but it passes through the through holes 15 of the partition plate 14 and flows into the upper activated carbon layer 4.
1, the activated carbon layer 41 is sequentially filled into the support bed 2 and the partition plate 14 to form a renewed lower activated carbon layer 41.

In addition, in the operation (b) above, even if water is supplied only from the water supply and drainage hole 7, the activated carbon in the lower activated carbon layer 42 can be transferred to the upper activated carbon layer 41, but in this case, it is necessary to increase the amount of water supplied, and the amount of water If the number is increased, the activated carbon in the upper activated carbon layer 41 will be stirred and the activated carbon will be mixed up and down, which is undesirable.

Further, even if water is supplied only from the water supply hole 16, the activated carbon can be transferred, but the activated carbon will not be transferred uniformly.

Therefore, if water is supplied from both the water supply and drainage holes 7 and the water supply holes 16 as described above, the water flow supplied from the water supply holes 16 will stir the activated carbon within the lower activated carbon layer 42, and the water supplied from the water supply holes 7 will cause the activated carbon to This is advantageous because it allows for efficient transfer of carbon from the through holes 15 to the upper activated carbon layer 41.

In addition, in the operation (c) above, the overall amount of water is reduced, and the water velocity flowing through the through hole 15 is set to the minimum flow velocity that does not allow the activated carbon to fall from the through hole 15 under its own weight. The role of the supplied water is to uniformly spray upward water from a large number of small through holes 3 in the support bed 2, and to make the activated carbon fed from the water supply holes 16 in a fluid state and uniformly distribute it on the support bed 2. It is something.

A part of the activated carbon fed into the lower activated carbon layer 42 during the operation (c) passes through the through hole 15 and enters the upper activated carbon layer 41.
However, since it remains in the lowest layer of the upper activated carbon layer 41, it does not cause any practical problems.

Next, the porosity of the partition plate 14, the diameter of the through holes 15, the flow velocity through the through holes 14, etc. will be described.

These include the particle size of activated carbon, the diameter of activated carbon adsorption tank 1, and the above (
The amount of water that can be used in the operations in (b) and (c) will be determined by taking into account the following.

The diameter of the through holes 15 is preferably larger than twice the particle size of the activated carbon and up to about 1/5 of the diameter of the activated carbon adsorption tank 1.

The porosity varies greatly depending on the shape and particle size of the activated carbon, but
It is about 1/100 to 1/5.

The flow velocity through the through holes 15 also varies greatly depending on the shape and diameter of the activated carbon, but when using spherical activated carbon with a diameter of about 2 mm, the flow velocity in the operation (b) above is 80 to 250 m.
/H is good, and the flow rate during the operation (c) above is 20 to 5
Approximately 0m/H is good.

In addition, if the water supply hole 16 is arranged so that water is injected from the tangential direction along the wall surface when the activated carbon adsorption tank 1 has a circular cross section, the activated carbon can be transferred or distributed uniformly in each operation. This is delicious.

In addition, piping is installed upward from the bottom of the activated carbon adsorption tank 1, and is opened at the top center of the support bed 2 so that water is discharged horizontally and in the tangential direction in all directions, creating a spiral water flow. You can also use it as

In this case, the water supply and drainage hole 7 will be shifted from the center, but this will not cause any practical problems.

The height of the activated carbon tank 1 can generally be lower than that of the conventional type, since the activated carbon can be frequently renewed one part at a time.

The height of the lower activated carbon layer 41 is theoretically determined mainly by water quality and renewal frequency, but from the viewpoint of migration and feeding of activated carbon to the upper part, 10 cm to 50 cm is appropriate.

In addition, if the tank diameter is 1 m and the height of the lower activated carbon layer is 20 cm, the time required to renew the activated carbon is approximately 5 minutes for the activated carbon in the lower activated carbon layer to move to the upper part, and approximately 10 minutes for the introduction of new activated carbon. The update took about 15 minutes.

In the embodiment described above, the partition plate 14 has circular through holes 15.
However, it may be a slit-like hole, a large number of rods or strips arranged in a blind shape, or a large number of metal balls or spherical particles of uniform size on a wire mesh or metal lattice. It may also be one lined with filter material.

The support bed 2 is not limited to a board with many thin holes 3 that do not contain activated carbon, but may also be thin slit-like holes.
In addition, a support bed of sand that is commonly used in the past (relatively coarse gravel is laid at the bottom, followed by thin layers of fine gravel and sand, and the surface is covered with sand finer than activated carbon). Alternatively, a strainer or the like may be used, although there are some unsatisfactories such as some activated carbon remaining in the upper part.

Furthermore, the activated carbon may be supplied in the form of a slurry from the water supply hole 16, or may be directly delivered and delivered by a screw conveyor or the like.

Furthermore, the method for removing contaminated activated carbon is not limited to the configuration in which the contaminated activated carbon is removed together with the overflow water from the overflow hole 10 shown in the embodiment. Needless to say.

Although the above embodiments have been explained using activated carbon as the adsorbent, the invention is not limited to activated carbon, and can be similarly applied to adsorption tanks using zeolite, molecular sieve, etc. as the adsorbent. Not even.

As described above, the present invention provides a water treatment apparatus having a downward flow type adsorbent layer, which includes a means for supplying backwash water from below the support bed, and a means for supplying backwash water from below the support bed, and a means for supplying the adsorbent layer stored in the adsorbent tank. A partition plate having a plurality of through holes larger than twice the particle size of the adsorbent divided into upper and lower halves, and an opening in the divided lower adsorbent layer, and a water flow when water is poured into the lower adsorbent layer. It is equipped with a water supply hole that stirs the adsorbent in the support bed, and an adsorbent feeding device that feeds and fills new adsorbent into the adsorbent layer below. Backwash water is supplied from below and water is supplied from the water supply hole to transfer the adsorbent forming the lower adsorbent layer to the lower layer of the upper adsorbent layer through the through hole of the partition plate. Then, with the amount of backwash water reduced, new adsorbent is fed by the adsorbent feeding device and filled between the support bed and the partition plate, thereby renewing the adsorbent layer. Since it is easy and quick to operate, it eliminates the need for a reserve tank, which was required in the past, and has great practical effects.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a conventional activated carbon adsorption tank, and FIG. 2 is a sectional view of an embodiment of the present invention. In the figure, 1 is the activated carbon tank body, 2 is the support bed, 4 is the activated carbon layer, 5 is the injection hole for the water to be treated, 6, 8, 9, 11
, 17 is an on-off valve, 7 is a water supply and drainage hole, 7a is a water supply pipe, 7b is a drain pipe, 10 is an overflow hole, 14 is a partition plate, 15 is a through hole, 1
6 is a water supply hole. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. Water to be treated containing adsorbed components is caused to flow down an adsorbent tank filled with the adsorbent, and the adsorbed components are adsorbed, and a support bed supporting the adsorbent layer is installed. In the device configured to backwash the adsorbent layer by supplying backwash water through a pump, the adsorbent layer is divided into upper and lower halves by a plurality of particles larger than twice the particle size of the filled adsorbent. a partition plate having a through hole; a water supply hole that opens into the lower adsorbent layer divided into two by the partition plate and forms a water flow that stirs the adsorbent in the lower adsorbent layer when water is poured; A device for feeding new adsorbent into the lower adsorbent layer, and when filling the new adsorbent, water is injected from the backwash water hole and the water injection hole, and the flow rate of water flowing through the through hole of the partition plate is adjusted. By setting the adsorbent to a predetermined value, the adsorbent forming the lower adsorbent layer is transferred to the lower layer of the upper adsorbent layer through the through hole, and then the amount of water injected is reduced to reduce the amount of water flowing through the through hole. The adsorbent feeding device is used to set a flow rate at such a rate that the adsorbent in the upper adsorption layer does not fall through the through hole. A water treatment device characterized in that an adsorbent is fed and filled to form a renewed adsorbent layer. 2. The water treatment device according to claim 1, wherein the adsorbent feeding device is configured to feed the adsorbent in slurry form from the water supply hole. 3 The backwash water overflow hole is opened near the upper surface of the upper adsorbent layer, and the contaminated adsorbent in the upper surface layer of the adsorbent layer is discharged out of the tank along with the overflow water. A water treatment device according to claim 1 or 2, characterized in that: