JPH08299974A - Double pipe type ozone contact reaction tank - Google Patents

Abstract

PURPOSE: To provide an ozone contact reaction tank which does not drop reaction efficiency of ozone with a substance to be removed even if a means in which an inexpensive outer diameter is thickened in respect of disposing to ensure reaction time is used. CONSTITUTION: Ozone-containing gas 3 is blown in water 1 to be treated which flows in from an upper part of an inner pipe 5, and the water 1 to be treated is allowed to fall in the inner pipe 5 together with the ozone-containing gas 3. Then, at a stage at which the water is raised in a space between the inner pipe 5 and an outer pipe (reaction vessel) 6 surrounding the inner pipe, a substance to be removed in the water 1 to be treated is removed by reacting it with ozone. In the reaction tank, the space between the inner pipe 5 and the outer pipe 6 is divided partially in a pipe peripheral direction with more than two flow straightening plates 11 in a pipe axis direction.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to water treatment such as water purification treatment, wastewater treatment, and industrial wastewater treatment, in which ozone is dissolved in water to be treated and the reaction between the ozone transferred to the water and the substance to be removed is efficiently performed. The present invention relates to an ozone contact reaction tank for carrying out, particularly a double-tube ozone contact reaction tank.

[0002]

2. Description of the Related Art FIG. S. Patent
No. 4 shows a conventional general double-tube type ozone contact reaction tank described in 4572821. In FIG. 7, 1 is treated water, 2 is treated water inflow pipe, 3 is gas containing ozone, 4 is gas blowing pipe containing ozone, 5 is inner pipe, 6 is outer pipe (reaction tank), and 7 is treatment Water, 8 is treated water outflow pipe, 9 is exhaust gas,
Reference numeral 10 is an exhaust gas extraction pipe. In the drawings shown below, the same reference numerals as those in FIG. 7 represent the same parts as those in FIG. 7.

This double-tube type ozone contact reaction tank is mainly composed of a vertical cylindrical outer tube 6 having a bottom and a vertical cylindrical inner tube 5 opened at the bottom of the outer tube 6, The space inside the inner pipe 5 and the space between the inner pipe 5 and the outer pipe 6 are ozone contact reaction tanks.

An ozone generator (not shown) converts a part of oxygen contained in a gas (usually air) sent from the outside into ozone to generate a gas 3 containing ozone. The ozone-containing gas 3 flows through the ozone-containing gas blowing pipe 4 provided in the upper portion of the inner pipe 5, and the treated water 1 sent from the treated water inflow pipe 2 by natural flow or a pump flows. It is blown into the inner pipe 5 that is inside. The water 1 to be treated flowing in the inner pipe 5 becomes a gas-liquid two-phase flow with the gas 3 containing ozone and descends in the inner pipe 5, while ozone is dissolved in the water 1 to be treated highly efficiently. Then, the gas-liquid two-phase flow formed by the water to be treated 1 and the gas 3 containing ozone flowing out from the lower end opening of the inner pipe 5 into the space between the inner pipe 5 and the outer pipe 6 becomes an upward flow. Ascend in this space. In this way, the harmful substances are oxidatively decomposed and removed by the dissolved ozone in the inner pipe 5 and the space between the inner pipe 5 and the outer pipe 6. The treated water 7 from which harmful substances have been removed flows out through the treated water outflow pipe 8. Further, the exhaust gas 9 is discarded from the exhaust gas extraction pipe 10.

The internal volume of the ozone contact reaction tank is designed to obtain a residence time commensurate with this in order to secure the time required for the reaction between ozone dissolved in water and the substance to be removed. Therefore, when the substance to be removed is a difficult-to-react substance and a long residence time is required, a contact reaction tank having a large internal volume is required. In the above-mentioned double-tube type ozone contact reaction tank, in order to achieve this object,
A means for increasing the length of the inner pipe or the outer pipe or increasing the diameter of the outer pipe is usually used.

[0006] In addition, such a double-tube type ozone contact reaction tank usually has a circular cross section, and most of it is underground because of its simplicity in construction and balance of the hydraulic pressure of the preceding and following processes. It is buried.

[0007]

However, when increasing the length of the inner pipe and the outer pipe, it is necessary to bury them deep in the ground, and if there is a hard rock in the middle, the excavation cost will increase significantly, This leads to an increase in construction costs. On the other hand, as the diameter of the outer tube is increased, a horizontal velocity distribution is generated in the upward flow in the contact reaction tank in the space between the inner tube and the outer tube, and the hydraulic characteristics in the contact reaction tank are ideal. The normal extruding flow changes to the reverse mixing flow. Along with this, a distribution occurs in the residence time of the water to be treated in the contact reaction tank, so that the reaction efficiency between the substance to be removed and ozone decreases.

The present invention has been made in order to solve such a problem. Even if a means for securing the reaction time by increasing the diameter of the outer tube, which is inexpensive to install, is used, the substance to be removed and ozone are removed. It is an object of the present invention to provide an ozone contact reaction tank that does not reduce the reaction efficiency of.

[0009]

Means for Solving the Problems The above-mentioned problems are as follows: A gas containing ozone is blown into the water to be treated flowing from the upper part of the inner pipe, and the water to be treated is lowered in the inner pipe together with the gas containing ozone. The inner tube and the outer tube surrounding it (reaction tank)
In a double-tube ozone contact reaction tank that removes the substance to be removed in the water to be treated by reacting with ozone in the process of raising the space between the inner pipe and the outer pipe. However, it is solved by a double tube type ozone contact reaction tank characterized in that it is partially divided in the tube circumferential direction by two or more straightening vanes in the tube axis direction.

If this space is divided in the circumferential direction by two or more partition plates (hereinafter referred to as rectifying plates) without changing the internal volume of the space between the inner tube and the outer tube which are the contact reaction tanks. ,
In the divided tanks, the cross-sectional area through which the ascending flow passes decreases, so flow turbulence is suppressed and the hydraulic characteristics come closer to the ideal extrusion flow, and the residence time distribution of the treated water in the contact reaction tank is distributed. Since it is made uniform, it is possible to prevent the reaction efficiency from decreasing even if the outer tube diameter is increased.

At this time, the above effect can be obtained even if the current plate is partially provided in the tube axis direction, but it is more effective if it is provided over the entire tube axis direction.

If the contact reaction tank is equally divided in the pipe circumferential direction by this straightening plate, the reaction in each divided tank becomes more uniform, so that the overall reaction efficiency can be further improved.

By fixing the current plate to the outer surface of the inner pipe, the turbulence of the flow can be further suppressed. When the straightening plate is installed so that the plate surface is parallel to the tube axis of the contact reaction tank, the turbulence of the flow can be further suppressed.

When the rectifying plate is provided with an ozone catalyst function, the catalyst and the water stream come into contact with each other efficiently, so that the radical generation is promoted, and the free radical reaction of this radical occurs in addition to the direct reaction by ozone. Can be promoted.

The layout conditions (number, size, set position, etc.) of the current plate are as follows: the substance to be removed, the internal volume of the contact reaction tank,
It must be determined in advance in consideration of the reaction time, the amount of gas containing ozone, etc.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a double-tube type ozone contact reaction tank which is an embodiment of the present invention. In FIG. 1, reference numeral 11 represents a current plate. In the following figures, 11 also represents a current plate.

In this double tube type ozone contact reaction tank, the space between the inner tube 5 and the outer tube 6 of the conventional double tube ozone contact reaction tank shown in FIG. It has a structure in which it is divided into three equal parts in the pipe circumferential direction by three straightening vanes 11 fixed to the inner wall of the outer pipe 6.

FIG. 2 shows a double-tube type ozone contact reaction tank which is an embodiment of the present invention. In this case, the structure is divided into three equal parts by three straightening vanes 11 fixed to the outer surface of the inner pipe 5 at two positions in the pipe axis direction.

FIG. 3 shows a double-tube type ozone contact reaction tank which is an embodiment of the present invention. In this case, the structure is divided into three equal parts by three straightening vanes 11 fixed to the outer surface of the inner pipe 5 and the inner wall of the outer pipe 6 at two positions in the pipe axial direction.

FIG. 4 shows a double-tube type ozone contact reaction tank which is an embodiment of the present invention. In this case, the structure is divided into two equal parts by two straightening vanes 11 fixed to the outer surface of the inner pipe 5 and the inner wall of the outer pipe 6 over the entire pipe axis direction.

FIG. 5 shows a double-tube type ozone contact reaction tank which is an embodiment of the present invention. In FIG. 5, reference numeral 12 represents a support.

In this case, the structure is divided into three equal parts by three straightening vanes 11 fixed to a support 12 provided to prevent vibration of the inner pipe 5 at two locations in the axial direction of the pipe.

FIG. 6 shows a double-tube type ozone contact reaction tank which is an embodiment of the present invention. In FIG. 6, 12 indicates a support.

In this case, the structure is divided into three equal parts by three straightening vanes 11 fixed to a support 12 provided to prevent vibration of the inner pipe 5 at four places in the pipe axis direction.

As shown in FIGS. 1 to 6, without changing the internal volume of the space between the inner tube 5 and the outer tube 6 which are the catalytic reaction tanks,
When this space is divided into a plurality of equalization plates 11 by a plurality of straightening vanes, the cross-sectional area through which the ascending flow passes decreases in each divided tank, so that the hydraulic characteristics become closer to the ideal extruding flow and Therefore, the reaction in each tank is made more uniform, so that the reaction efficiency can be greatly improved as compared with the conventional double-tube ozone contact reaction tank shown in FIG.

Which one is better cannot be determined because it depends on the dimensions of the inner pipe, the outer pipe, and the straightening vane, but if the dimensions are the same, it is better to provide the straightening vane over the entire pipe axial direction, or to arrange the straightening vane inside It is more effective to fix it on the outer surface.

In order to give the current plate a function of ozone catalyst,
The rectifying plate itself may be made of an ozone catalyst substance, or a rectifying plate surface-treated with the ozone catalyst substance may be used. As the ozone catalyst substance, titanium oxide, zinc oxide, iron oxide, tungsten trioxide, nickel salt, cobalt salt and the like are preferable.

[0028]

Since the present invention is configured as described above, the cross-sectional area of the contact reaction tank can be increased without changing the hydraulic characteristics of the water flow rising in the space between the inner pipe and the outer pipe. It is possible to provide a double-tube type ozone contact reaction tank in which a sufficient internal volume of the contact reaction tank can be obtained. As a result, even if the planned amount of treated water is large or it takes a long time to treat the substance to be removed, it can be dealt with without problems. In addition, although the excavation cost is expected to increase under hard rock or other installation conditions, the use of the double-tube ozone contact reaction tank of the present invention can be accommodated by changing the thickness of the outer tube. It can be greatly reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing a double-tube ozone contact reaction tank which is an embodiment of the present invention.

FIG. 2 is a view showing a double-tube type ozone contact reaction tank which is an embodiment of the present invention.

FIG. 3 is a diagram showing a double-tube type ozone contact reaction tank which is an embodiment of the present invention.

FIG. 4 is a view showing a double-tube type ozone contact reaction tank which is an embodiment of the present invention.

FIG. 5 is a view showing a double-tube type ozone contact reaction tank which is an embodiment of the present invention.

FIG. 6 is a diagram showing a double-tube ozone contact reaction tank which is an embodiment of the present invention.

FIG. 7 is a view showing a conventional general double tube type ozone contact reaction tank.

[Explanation of symbols]

 1 treated water 2 treated water inflow pipe 3 gas containing ozone 4 gas blowing pipe containing ozone 5 inner pipe 6 outer pipe (reaction tank) 7 treated water 8 treated water outflow pipe 9 exhaust gas 10 exhaust gas extraction pipe 11 straightening plate 12 support

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toraro Minegishi, Marunouchi 1-2-2, Chiyoda-ku, Tokyo Nihon Kokan Co., Ltd. (72) Haruhi Yokota 1-2-1 Marunouchi, Chiyoda-ku, Tokyo Nippon Steel Tube Co., Ltd. (72) Inventor Junji Tada 1-2 1-2 Marunouchi, Chiyoda-ku, Tokyo Nihon Steel Tube Co., Ltd.

Claims (7)

[Claims] 1. A gas containing ozone is blown into the water to be treated flowing from the upper part of the inner pipe, the water to be treated is lowered in the inner pipe together with the gas containing ozone, and then the inner pipe and an outer wall surrounding it. A double-tube ozone contact reaction tank that removes a substance to be removed in the water to be treated by reacting with ozone in the process of raising the space between the tubes (reaction tanks), wherein the inner tube and the outer tube are A double-tube ozone contact reaction tank characterized in that the space between the two is partially divided in the tube circumferential direction by two or more straightening vanes in the tube axis direction. 2. The space between the inner pipe and the outer pipe,
The double tube type ozone contact reaction tank according to claim 1, wherein the double tube type ozone contact reaction tank is partially divided in the tube axis direction in the tube circumferential direction by two or more straightening vanes. 3. The space between the inner pipe and the outer pipe,
The double-tube ozone contact reaction tank according to claim 1, wherein the double-tube ozone contact reaction tank is divided in the tube circumferential direction by two or more rectifying plates over the entire tube axis direction. 4. The space between the inner pipe and the outer pipe,
The double tube type ozone contact reaction tank according to claim 3, wherein the double tube ozone contact reaction tank is equally divided in the tube circumferential direction by two or more straightening vanes over the entire tube axis direction. 5. The double-tube ozone contact reaction tank according to claim 1, wherein the straightening plate is fixed to the outer surface of the inner tube. 6. The plate surface of the rectifying plate is parallel to the tube axis of the double-tube type ozone contact reaction tank, according to any one of claims 1 to 5. Double tube ozone contact reaction tank. 7. The one of claims 1 to 6, wherein the straightening vane has an ozone catalyst function.
The double-tube ozone contact reaction tank according to item.