JP2001205277A - Method and apparatus for removing hardly decomposable organic compound in water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and apparatus capable of effectively removing a hardly decomposable organic compound such as dioxin, an endocrine disruptor or the like contained in seeping water, sewage, industrial wastewater, river water, lake and marsh water, basin water, tap water or ground water. SOLUTION: Water to be treated is oxidized in the presence of an oxidizer in a catalytic oxidizing column 4 and subsequently oxidized by ultraviolet rays and ozone in an accelerated oxidation column 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to dioxin contained in water such as leachate, sewage, industrial wastewater, river water, lake water, pond water, tap water, groundwater, etc. The present invention relates to a method and an apparatus for removing a compound.

[0002]

2. Description of the Related Art Conventionally, leachate generated along with rainwater from a waste storage site of a general waste final disposal site is introduced into a regulating tank and a calcium removal facility as shown in a flowchart of FIG. After that, it adjusts pH and removes calcium, and then sends it to biological treatment equipment to biologically treat organic matter and nitrogen components in sewage by contact aeration and rotating disk method. Then, the biologically treated water is introduced into a coagulation tank to coagulate contaminants by adding a coagulant, and the coagulated water is sent to a coagulation sedimentation tank to settle and separate the agglomerates. It is discharged outside the system as treated water through the tower.

[0003]

However, harmful hard-to-decompose organic compounds such as dioxins contained in trace amounts of effluent such as leachate at final disposal sites and industrial wastewater as described above are as described above. It often remains without being treated by the method.

The present invention effectively removes hardly decomposable organic compounds such as dioxins and environmental hormones contained in leachate, sewage, industrial effluent, river water, lake water, pond water, tap water, groundwater and the like. An object of the present invention is to provide a method and an apparatus that can perform the method.

[0005]

In order to solve the above-mentioned problems, a first method for removing a hardly decomposable organic compound in water is as follows.
The water to be treated is oxidized with ozone in the presence of an oxidation catalyst in a catalytic oxidation tower, and then further oxidized with ultraviolet light and ozone in a promoted oxidation tower.

A second method for removing hardly decomposable organic compounds in water is to oxidize water to be treated with ultraviolet light and ozone in a promoted oxidation tower, and then in a catalytic oxidation tower with ozone in the presence of an oxidation catalyst. It is characterized by performing an oxidation treatment.

A third method for removing hardly decomposable organic compounds in water is to oxidize water to be treated with ozone in the presence of an oxidation catalyst in a catalytic oxidation zone of an oxidation reaction tower, and then to promote accelerated oxidation of the tower. It is characterized in that the zone is further oxidized with ultraviolet light and ozone.

In a fourth method for removing hardly decomposable organic compounds in water, the water to be treated is oxidized with ultraviolet light and ozone in an accelerated oxidation zone of an oxidation reaction tower, and then the presence of an oxidation catalyst in a catalytic oxidation zone. It is characterized in that it is oxidized with ozone below.

A fifth method for removing hardly decomposable organic compounds in water is characterized in that water to be treated is oxidized with ozone in a catalytic oxidation tower in the presence of an oxidation catalyst.

In the first to fifth methods, the water to be treated is, for example, leachate discharged from a waste storage site of a general waste final disposal site along with rainwater, clean water, sewage, industrial waste water, or the like.
River water, lake water, pond water, tap water, groundwater, etc.
Such water often contains persistent organic compounds such as dioxins and environmental hormones.

As the oxidation catalyst, Mn, Ni, Cr, F
Those containing an oxide of a metal such as e are preferable.

As ozone, it is preferable to use ozone gas produced by a water electrolysis method. The optimum injection rate of ozone is 50 to 500 mg / L, but the optimum injection rate may vary depending on the content of components such as COD.

In the first method, water to be treated is supplied to the catalytic oxidation tower so as to flow upward from the bottom, and water oxidized in the catalytic oxidation tower is taken out from the top as primary treated water, and the primary treated water is treated. May be supplied to the promoted oxidation tower from the bottom so as to flow upward, and water oxidized in the promoted oxidation tower may be taken out from the top as secondary treated water. Also, the water to be treated is supplied to the catalytic oxidation tower in a downward flow from the top, the water oxidized in the catalytic oxidation tower is taken out from the bottom as primary treated water, and the primary treated water is supplied to the accelerated oxidation tower from the top. In some cases, the water is supplied in a downward flow, and the water oxidized by the accelerated oxidation tower is taken out from the bottom as secondary treated water.

In the second method, the water to be treated is supplied to the promoted oxidation tower so as to flow upward from the bottom, and the water oxidized in the promoted oxidation tower is taken out from the top as primary treated water, and is treated as primary treated water. May be supplied to the catalytic oxidation tower from the bottom so as to flow upward, and water oxidized in the catalytic oxidation tower may be taken out from the top as secondary treated water. In addition, water to be treated is supplied to the promoted oxidation tower from the top in a downward flow, water oxidized in the promoted oxidation tower is taken out from the bottom as primary treated water, and the primary treated water is supplied to the catalytic oxidation tower from the top. In some cases, water is supplied in a downward flow, and water oxidized in the catalytic oxidation tower is taken out from the bottom as secondary treated water.

In the third method, the water to be treated is supplied to the oxidation reaction tower so as to flow upward from the bottom, and the water which has been sequentially oxidized in the catalytic oxidation zone below the column and the accelerated oxidation zone above the column is removed. It may be taken out from the top as treated water. Also, water to be treated is supplied to the oxidation reaction tower from the top in a downward flow, and water that has been sequentially oxidized in the catalytic oxidation zone on the upper side of the tower and the promoted oxidation zone on the lower side is taken out as treated water from the bottom. In some cases.

In the fourth method, the water to be treated is supplied to the oxidation reaction tower so as to flow upward from the bottom, and the water which has been sequentially oxidized in the promoted oxidation zone at the lower side of the tower and the catalytic oxidation zone at the upper side of the tower is removed. It may be taken out from the top as treated water. In addition, water to be treated is supplied to the oxidation reaction tower from the top in a downward flow, and water that has been sequentially oxidized in the promoted oxidation zone on the upper side of the tower and the catalytic oxidation zone on the lower side is taken out as treated water from the bottom. In some cases.

In the fifth method, water to be treated is supplied to the catalytic oxidation tower so as to flow upward from the bottom, ozone is diffused into the tower from the bottom, and water oxidized in the tower is supplied to the top. May be taken out as treated water. Also, the water to be treated is supplied to the catalytic oxidation tower from the top in a downward flow, the ozone is diffused into the tower from the bottom, and the water oxidized in the tower is taken out as treated water from the bottom. is there.

In the first and second methods, it is preferable that a part of the primary treated water generated in the catalytic oxidation tower is removed from the top or bottom of the tower and circulated to the bottom or top of the tower. In the third and fourth methods, it is preferable that a part of the treated water generated in the oxidation reaction tower be taken out from the top or bottom of the tower and circulated to the bottom or top of the tower. In addition, the fifth
In the above method, it is preferable that a part of the treated water generated in the catalytic oxidation tower is taken out from the top or bottom of the tower and circulated to the bottom or top of the tower. By circulating such primary treated water or treated water, there is obtained an advantage that efficient oxidative decomposition is achieved by increasing the contact area between the catalyst and ozone.
Passing gas through the catalyst is very difficult, such as creating a channel through which gas can escape in the catalyst layer.However, by circulating the primary treatment water as described above, the flow velocity in the tube can be increased, and Gas can be passed.

In the first to fifth methods, the amount of dissolved ozone at the top of the catalytic oxidation tower or at the top of the oxidation reaction tower is measured, and when the measured value falls below a set value, ozone can be supplied to the tower. . Thus, the ozone shortage is grasped by the ozone concentration meter, and when the concentration becomes lower than the set concentration, ozone is supplied from the ozone generator.

In the first and third methods, if the water supplied to the promoted oxidation zone of the promoted oxidation tower or the oxidation reaction tower contains the SS component, the irradiation of ultraviolet rays is hindered.
A catalytic oxidation tower or catalytic oxidation zone from which components can also be removed is disposed upstream of the promoted oxidation tower or promoted oxidation zone. Thereby, in the promoted oxidation tower or the promoted oxidation zone, the stain of the SS component does not easily adhere to the ultraviolet lamp, and maintenance is easy.

In the first to fourth methods, an organic compound which is hardly oxidized by a catalyst is oxidatively decomposed in a promoted oxidation tower or a promoted oxidation zone by using both ozone and ultraviolet rays.

In the first and second methods, it is preferable that the ozone used in the catalytic oxidation tower is sent from the top of the catalytic oxidation tower to the promotion oxidation tower, and then returned from the promotion oxidation tower to the catalyst oxidation tower again. In the third and fourth methods, it is preferable to return the ozone used in the oxidation reaction tower from the top to the bottom of the oxidation reaction tower. In the fifth method, it is preferable to return the ozone used in the catalytic oxidation tower from the top to the bottom of the same. As a result, the amount of ozone used can be minimized. The optimum injection rate of ozone in the catalytic oxidation tower, the promotion oxidation tower and the oxidation reaction tower is 50 to 500 mg / L, but the optimum injection rate may differ depending on the content of components such as COD.

In the fifth method, when the concentration of the hardly decomposable organic compound in the water is high or when the concentration of the compound in the treated water is required to be extremely low, a plurality of, for example, 3 to 5 groups are used. Preferably, the catalytic oxidation towers are arranged in series.

In the first to fifth methods, it is preferable to add an oxidizing agent to the water to be treated in advance. As the oxidizing agent to be added to the water to be treated, a common oxidizing agent such as sodium hypochlorite and aqueous hydrogen peroxide can be used.

In order to carry out the first method, a removing device comprising a catalytic oxidation tower filled with an oxidation catalyst and supplied with ozone and a promoting oxidation tower provided with an ultraviolet lamp and supplied with ozone is used. The water to be treated is oxidatively decomposed with ozone in a catalytic oxidation tower in the presence of an oxidation catalyst, and then further oxidized with ultraviolet light and ozone in a promoted oxidation tower.

In order to carry out the second method, a removing device comprising a promotion oxidation tower having a built-in ultraviolet lamp and supplied with ozone and a catalytic oxidation tower filled with an oxidation catalyst and supplied with ozone is used. The water to be treated is oxidized with ultraviolet light and ozone in a promoted oxidation tower, and then oxidized with ozone in the catalytic oxidation tower in the presence of an oxidation catalyst.

In order to carry out the third method, there is provided a catalytic oxidation zone filled with an oxidation catalyst and an accelerated oxidation zone containing a built-in ultraviolet lamp, and these zones are supplied with ozone. Using a removal device consisting of a reaction tower, the water to be treated is oxidized with ozone in the presence of an oxidation catalyst in the catalytic oxidation zone, and then further oxidized with ultraviolet light and ozone in the accelerated oxidation zone.

In order to carry out the fourth method, there is provided an oxidation zone having a built-in ultraviolet lamp and a catalyst oxidation zone filled with an oxidation catalyst, and these zones are supplied with ozone. Using a removal device consisting of a reaction tower, the water to be treated is oxidized with ultraviolet light and ozone in a promoted oxidation zone and then oxidized with ozone in the catalytic oxidation zone in the presence of an oxidation catalyst.

In order to carry out the fifth method, a removal device comprising a catalytic oxidation tower filled with an oxidation catalyst and supplied with ozone is used. Oxidation treatment.

In the apparatus for carrying out the first and second methods, a water inlet is provided at the bottom of the catalytic oxidation tower and the promoted oxidation tower, and a water outlet is provided at the top of the catalytic oxidation tower and the promoted oxidation tower. In some cases, the flow of water may be upward. Further, a water inlet is provided at the top of the catalytic oxidation tower and the promoted oxidation tower, and a water outlet is provided at the bottom of the catalytic oxidation tower and the promoted oxidation tower. is there.

In the apparatus for carrying out the third method, a catalytic oxidation zone is provided below the oxidation reaction tower and a promotion oxidation zone is provided above the oxidation reaction tower, and a water inlet is provided at the bottom of the oxidation reaction tower. Water outlets are provided at the tops, respectively, and the flow of water in the oxidation reaction tower may be upward.
In addition, a catalytic oxidation zone is provided above the oxidation reaction tower, and a promotion oxidation zone is provided below the oxidation reaction tower. A water inlet is provided at the top of the tower, and a water outlet is provided at the bottom of the tower. The flow of water in the reaction tower may be a downward flow.

In the apparatus for carrying out the fourth method, a promotion oxidation zone is provided below the oxidation reaction tower and a catalyst oxidation zone is provided above the oxidation reaction tower, and a water inlet is provided at the bottom of the tower. Water outlets are provided at the tops, respectively, and the flow of water in the oxidation reaction tower may be upward.
In addition, a promoted oxidation zone is provided above the oxidation reaction tower, and a catalytic oxidation zone is provided below the oxidation reaction tower. A water inlet is provided at the top of the tower, and a water outlet is provided at the bottom thereof. The flow of water in the reaction tower may be a downward flow.

In the apparatus for carrying out the fifth method, a water inlet may be provided at the bottom of the catalytic oxidation tower and a water outlet may be provided at the top of the catalytic oxidation tower, and the flow of water in the tower may be upward. is there. A water inlet may be provided at the top of the catalytic oxidation tower, and a water outlet may be provided at the bottom of the catalytic oxidation tower, so that the flow of water in the tower may be a downward flow.

The apparatus for performing the first and second methods is provided with a waste ozone treatment apparatus for decomposing waste ozone discharged from the top of the catalytic oxidation tower and / or the promotion oxidation tower. preferable. It is preferable that the apparatus for performing the third and fourth methods includes a waste ozone treatment apparatus for decomposing waste ozone discharged from the top of the oxidation reaction tower. Further, it is preferable that the apparatus for performing the fifth method includes a waste ozone treatment apparatus for decomposing waste ozone discharged from the top of the catalytic oxidation tower.

[0035] In the apparatus for carrying out the first to fifth methods, the waste ozone treatment apparatus further comprises a top of a catalytic oxidation tower and / or a promotion oxidation tower, a top of an oxidation reaction tower or a top of a catalytic oxidation tower, and a waste ozone treatment apparatus. In some cases, a gas-liquid separation tower is provided.

It is preferable that the apparatus for performing the first to fifth methods further includes an oxidizing agent supply device for adding an oxidizing agent to water to be treated in advance.

[0037]

In the first and second methods, a catalytic oxidation tower filled with an oxidation catalyst and a promoted oxidation tower equipped with an ultraviolet irradiation device are arranged in series, and ozone is diffused into each of them. Hydroxy radical having the strongest oxidizing power is generated in the tower. In the third and fourth methods, a catalyst oxidation zone filled with an oxidation catalyst and a promotion oxidation zone provided with an ultraviolet irradiation device are arranged in series in an oxidation reaction tower, and each of them is diffused with ozone. Then, a hydroxyl radical is generated in the tower. In the fifth method, ozone is diffused into a catalytic oxidation tower filled with an oxidation catalyst, and hydroxyl radicals are generated in the tower. In the first to fifth methods, if an oxidizing agent is added to the water to be treated in advance, more hydroxyl radicals are generated in each column. These hydroxyl radicals can decompose hard-to-decompose organic compounds such as dioxins and environmental hormones contained in water.

The oxidation catalyst loses one molecule of oxygen to generate a hydroxyl radical, but one molecule of oxygen can be obtained by supplying ozone, so that it can be used semipermanently. As a result, metals and the like contained in the catalyst rarely leak.

[0039]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will now be described with reference to FIGS.
This will be described with reference to FIG.

Embodiment 1 This embodiment shows an embodiment of the first removing method according to the present invention, and its flow sheet is shown in FIG. In this embodiment, water that has passed through the sand filtration tower and the activated carbon adsorption tower in the processing flow described above with reference to FIG. 12 is treated as the water to be treated. In FIG. 1, water to be treated is introduced into a regulating tank (2), from which a raw water supply pump is supplied.
It is sent to the catalytic oxidation tower (4) by (3). A catalyst layer (5) is provided in the catalytic oxidation tower (4), and the catalyst layer (5) is packed with a catalyst supporting a metal oxide. The above water is used as a catalytic oxidation tower
(4) Water is supplied from a water inlet provided at the bottom of the navel, and ozone is injected and diffused from the bottom through an ozone line (6) from an ozone generator (13). At the same time, in order to circulate the primary treated water in the catalytic oxidation tower (4), a part of the water is returned from the top to the bottom of the catalytic oxidation tower (4) through the circulation line (7) by the circulation pump (8).

The remaining primary treated water is discharged from a water outlet provided at the top of the catalytic oxidation tower (4), and then supplied to the promoted oxidation tower (9) from a water inlet provided at the bottom thereof.
Dioxin that could not be decomposed in the catalytic oxidation tower (4),
Here, hardly decomposable organic compounds such as environmental hormones are oxidatively decomposed. The accelerated oxidation tower (9) has a vertically built-in ultraviolet lamp (10), which reacts ultraviolet light with ozone to generate hydroxy radicals, which decompose dioxin and other hardly decomposable organic compounds. . The treated secondary treated water is discharged from a water outlet provided at the top of the promoted oxidation tower (9).

Ozone is sent from the top of the catalytic oxidation tower (4) to the promotion oxidation tower (9) by the gas circulation pump (11) and used. The remaining ozone is returned to the catalytic oxidation tower (4) again.
The shortage of ozone due to the use in both reactors,
Ozone is supplied from the ozone generator (13) when the concentration becomes lower than or equal to the set value, which is grasped by the ozone concentration measurement control device (12) provided in the catalytic oxidation tower. This allows the use of ozone to be minimized. In order to remove a small amount of waste ozone, an exhaust port is provided at the top of the catalytic oxidation tower (4), and a waste ozone treatment device (1) is connected to it, and the device (1) decomposes waste ozone. did.

Embodiment 2 This embodiment shows another embodiment of the first removing method according to the present invention, and its flow sheet is shown in FIG. As shown in FIG. 2, in this embodiment, the injection and diffusion of ozone into the bottom of the catalytic oxidation tower (4) and the bottom of the promotion oxidation tower (9) are all performed by an ozone generator (13).
Going through (6). Further, exhaust ports are provided at the top of the catalytic oxidation tower (4) and the top of the promoted oxidation tower (9), and a waste ozone decomposer (1) is connected to these exhaust ports. (9)
Decomposes waste ozone discharged from In this embodiment, the gas circulation pump does not circulate ozone between the catalytic oxidation tower (4) and the promotion oxidation tower (9),
The catalytic oxidation tower (4) is not provided with an ozone concentration measurement control device. Further, the circulation of the primary treated water in the catalytic oxidation tower (4) was not performed in this embodiment. In other respects, processing was performed in the same manner as in Example 1.

Embodiment 3 This embodiment shows still another embodiment of the first removing method according to the present invention, and its flow sheet is shown in FIG. As shown in FIG. 3, in this embodiment,
Water to be treated coming from the regulating tank (2) is supplied to the catalytic oxidation tower (4) so as to flow downward from a water inlet provided at the top thereof,
Water oxidized in the catalytic oxidation tower (4) is taken out as primary treated water from a water outlet provided at the bottom of the tower (4). Next, this primary treated water is supplied to the promoted oxidation tower (9) so as to flow downward from a water inlet provided at the top of the promoted oxidation tower (9).
Water oxidized in (9) is taken out as secondary treated water from a water outlet provided at the bottom of the tower (9). Other points are
The processing was performed in the same manner as in Example 2.

Embodiment 4 This embodiment shows an embodiment of the second removing method according to the present invention, and its flow sheet is shown in FIG. This embodiment is also the same in that the water that has passed through the sand filtration tower and the activated carbon adsorption tower in the processing flow described above with reference to FIG. 12 is treated as the water to be treated. In FIG. 4, water to be treated is introduced into a regulating tank (2), from which it is sent to a promoted oxidation tower (9) by a raw water supply pump (3).
An ultraviolet lamp (10) is vertically built in the promoted oxidation tower (9). The above water is supplied to the promoted oxidation tower (9) from the bottom thereof, and ozone is further supplied from an ozone generator (13) to an ozone line.
In (6), air is injected from the bottom. In the promoted oxidation tower (9), hydroxyl radicals are generated by reacting ultraviolet rays and ozone, and the hydroxyl radicals are decomposed in dioxin and other hardly decomposable organic compounds, particularly in the catalytic oxidation tower (4) described below. Oxidatively decomposes difficult-to-decompose organic compounds.

The primary treated water taken out from the promoted oxidation tower (9) is supplied into the catalytic oxidation tower (4), and is difficult to decompose in the promoted oxidation tower (9). Is oxidatively decomposed here. Catalytic oxidation tower
A catalyst layer (5) is provided in (4), and the catalyst layer (5) is packed with a catalyst supporting a metal oxide. The above water is supplied to the catalytic oxidation tower (4) from the bottom thereof, and furthermore, an ozone generator
From (13), ozone is injected and diffused from the bottom through an ozone line (6). The treated secondary treated water is discharged from the top of the catalytic oxidation tower (4).

In order to remove a small amount of waste ozone, exhaust ports are provided at the top of the promotion oxidation tower (9) and the top of the catalyst oxidation tower (4), respectively, and the waste ozone treatment device (1) is connected to these exhaust ports. Then, the waste ozone was decomposed by the same device (1).

Embodiment 5 This embodiment shows another embodiment of the second removing method according to the present invention, and its flow sheet is shown in FIG. As shown in FIG. 5, in this embodiment, the adjustment tank
The water to be treated coming from (2) is supplied to the promoted oxidation tower (9) so as to flow downward from a water inlet provided at the top of the promoted oxidation tower (9). It is taken out as primary treated water from a water outlet provided at the bottom of the tower (9). Next, this primary treated water is supplied to the catalytic oxidation tower (4) from the water inlet provided at the top so as to flow downward, and the water oxidized by the catalytic oxidation tower (4) is supplied to the tower (4). It is taken out as secondary treated water from a water outlet provided at the bottom. Otherwise, the processing was performed in the same manner as in Example 4.

Embodiment 6 This embodiment is a modification of Embodiments 1 to 5, and FIG. 6 shows a flow sheet thereof. As shown in FIG. 6, in the process of transferring water from the regulating tank (2) to the catalytic oxidation tower (4), the water to be treated is supplied from the oxidizing agent tank (14) via the supply pump (15) to the water to be treated. Add sodium or hydrogen peroxide solution. As a result, more hydroxyl radicals are generated in the subsequent catalytic oxidation tower (4) and promoted oxidation tower (9). Otherwise, the processing was performed in the same manner as in Examples 1 to 5.

Embodiment 7 This embodiment shows an embodiment of the third removing method according to the present invention, and its flow sheet is shown in FIG. This embodiment is also the same in that the water that has passed through the sand filtration tower and the activated carbon adsorption tower in the processing flow described above with reference to FIG. 12 is treated as the water to be treated. In FIG. 7, water to be treated is introduced into a regulating tank (2), from which it is sent to an oxidation reaction tower (16) by a raw water supply pump (3). The oxidation reaction tower (16) is a stepped cylindrical one having an upper small diameter portion and a lower large diameter portion. At the lower large-diameter portion of the oxidation reaction tower (16), a catalyst layer (5) packed with a catalyst supporting a metal oxide is provided, and the large-diameter portion has a catalytic oxidation zone.
(16A). An ultraviolet lamp (10) is vertically built in an upper small-diameter portion of the oxidation reaction tower (16), and the small-diameter portion constitutes an accelerated oxidation zone (16B).

The water is supplied to the oxidation reaction tower (16) from a water inlet provided at the bottom of the oxidation reaction tower (16). At the same time, the water is generated in the oxidation reaction tower (16) by the ozone generator (13). Ozone is passed through the ozone line (6) to the oxidation reaction tower (16)
7) Inject and diffuse more. The water flowing upward in the oxidation reaction tower (16) first enters the catalytic oxidation zone (16A), where ozone is reacted in the presence of an oxidation catalyst to generate hydroxy radicals. Oxidatively decomposes insoluble organic compounds in water, including hormones. Next, water enters the accelerated oxidation zone (16B), where hydroxyl radicals are generated by reacting ultraviolet light and ozone, and dioxins and environmental hormones that could not be completely decomposed in the catalytic oxidation zone (16A) by the hydroxyl radicals. Oxidatively decomposes hard-to-decompose organic compounds. The treated water is discharged from a water outlet provided at the top of the oxidation reaction tower (16).

A small amount of waste ozone is discharged from an exhaust port provided at the top of the oxidation reaction tower (16), and is separated from water in a gas-liquid separation tower (18) connected to the exhaust port. 1)
And was decomposed here.

Embodiment 8 This embodiment shows an embodiment of the fourth removing method according to the present invention, and its flow sheet is shown in FIG. This embodiment is also the same in that the water that has passed through the sand filtration tower and the activated carbon adsorption tower in the processing flow described above with reference to FIG. 12 is treated as the water to be treated. In FIG. 8, water to be treated is introduced into a regulating tank (2), from which it is sent to an oxidation reaction tower (16) by a raw water supply pump (3). The oxidation reaction tower (16) is a stepped cylindrical one having an upper small diameter portion and a lower large diameter portion. At the lower large-diameter portion of the oxidation reaction tower (16), a catalyst layer (5) packed with a catalyst supporting a metal oxide is provided, and the large-diameter portion has a catalytic oxidation zone.
(16A). An ultraviolet lamp (10) is vertically built in an upper small-diameter portion of the oxidation reaction tower (16), and the small-diameter portion constitutes an accelerated oxidation zone (16B).

The water is supplied to the oxidation reaction tower (16) from a water inlet provided at the top thereof, and at the same time, the water is generated in the oxidation reaction tower (16) by the ozone generator (13). Ozone is passed through the ozone line (6) to the oxidation reaction tower (16)
7) Inject and diffuse more. The water flowing downward in the oxidation reaction tower (16) first enters the accelerated oxidation zone (16B), where a hydroxyl radical is generated by reacting ultraviolet light and ozone, and the hydroxyl radical generates a hydroxyl radical in the catalytic oxidation zone (16A). It oxidatively decomposes hardly decomposable organic compounds in water such as dioxins and environmental hormones that are difficult to decompose.
The water then enters the catalytic oxidation zone (16A), where hydroxyl radicals are generated by reacting ozone in the presence of the oxidation catalyst, which hydroxyl radicals did not decompose in the accelerated oxidation zone (16B). Oxidatively decomposes hardly decomposable organic compounds such as dioxin. The treated water is discharged from a water outlet provided at the bottom of the oxidation reaction tower (16).

A small amount of waste ozone is discharged from an exhaust port provided at the top of the oxidation reaction tower (16), and separated from treated water in a gas-liquid separation tower (18) connected to the exhaust port.
It was sent to (1), where it was disassembled.

Embodiment 9 This embodiment is a modification of Embodiments 7 and 8, and its flow sheet is shown in FIG. FIG.
As shown in the figure, in the process of transferring water from the adjustment tank (2) to the oxidation reaction tower (16), the water to be treated from the oxidant tank (14) via the supply pump (15) is added to sodium hypochlorite or Add hydrogen peroxide solution. Thereby, more hydroxyl radicals are generated in the catalytic oxidation zone (16A) and the promoted oxidation zone (16B) of the subsequent oxidation reaction tower (16). Otherwise, the processing was performed in the same manner as in Examples 7 and 8.

Embodiment 10 This embodiment shows an embodiment of the fifth removing method according to the present invention, and its flow sheet is shown in FIG. This embodiment is also the same in that the water that has passed through the sand filtration tower and the activated carbon adsorption tower in the processing flow described above with reference to FIG. 12 is treated as the water to be treated. FIG.
At 0, the water to be treated is introduced into a regulating tank (2), from which it is sent by a raw water supply pump (3) to a catalytic oxidation tower (4).

A catalyst layer (5) is provided in the catalytic oxidation tower (4), and the catalyst layer (5) is packed with a catalyst supporting a metal oxide. The water is supplied to the catalytic oxidation tower (4) from a water inlet provided at the bottom thereof, and ozone is injected and diffused from the bottom of the ozone generator (13) through the ozone line (6). At the same time, to circulate the primary treated water in the catalytic oxidation tower (4),
Part of the water is returned from the top to the bottom of the catalytic oxidation tower (4) through the circulation line (7) by the circulation pump (8), and the remaining treated water is discharged from the water outlet provided at the top of the catalytic oxidation tower (4). From the system.

The ozone discharged from the top of the catalytic oxidation tower (4) is circulated by returning it to the bottom of the catalytic oxidation tower (4) by a gas circulation pump (11).

The ozone deficient due to use in the catalytic oxidation tower (4) is grasped by an ozone concentration measurement control device (12) provided in the tower, and when the concentration falls below a set concentration, an ozone generator is used. Ozone is supplied from (13). This allows the use of ozone to be minimized.
In order to remove a small amount of waste ozone, a catalytic oxidation tower
An exhaust port is provided at the top of (4), and there is a waste ozone decomposer (1)
And the same apparatus (1) was used to decompose waste ozone.

Embodiment 11 This embodiment shows another embodiment of the fifth removing method according to the present invention, and its flow sheet is shown in FIG. In this embodiment, in the process of transferring water from the regulating tank (2) to the catalytic oxidation tower (4), the supply pump is supplied from the oxidizing tank (14).
Add sodium hypochlorite or hydrogen peroxide to the water to be treated via (15). Thereby, more hydroxyl radicals are generated in the subsequent catalytic oxidation tower (4). The other points were the same as in Example 10.

[0062]

According to the method of the present invention, leachate, sewage,
It is possible to effectively remove hard-to-decompose organic compounds such as dioxins and environmental hormones contained in industrial wastewater, river water, lake water, pond water, tap water, groundwater, and the like.

[Brief description of the drawings]

FIG. 1 is a flow sheet showing a method of Example 1.

FIG. 2 is a flow sheet showing a method of Example 2.

FIG. 3 is a flow sheet showing a method of Example 3.

FIG. 4 is a flow sheet showing a method of Example 4.

FIG. 5 is a flow sheet showing a method of Example 5.

FIG. 6 is a flow sheet showing a method of Example 6.

FIG. 7 is a flow sheet showing a method of Example 7.

FIG. 8 is a flow sheet showing a method of an eighth embodiment.

FIG. 9 is a flow sheet showing a method of Example 9.

FIG. 10 is a flow sheet showing a method of Example 10.

FIG. 11 is a flow sheet showing a method of Example 11.

FIG. 12 is a flow sheet showing a conventional method.

[Explanation of symbols]

 (1): Waste ozone removal device (2): Regulating tank (3): Raw water supply pump (4): Catalytic oxidation tower (5): Catalyst bed (6): Ozone line (7): Circulation line (8): Circulation pump (9): Accelerated oxidation tower (10): UV lamp (11): Gas circulation pump (12): Ozone concentration measurement control device (13): Ozone generator (14): Oxidizer tank (15): Oxidation Agent supply pump (16): Oxidation reaction tower (16A): Catalytic oxidation zone (16B): Accelerated oxidation zone (17): Aeration tube (18): Gas-liquid separation tower

Continued on the front page (72) Inventor Shiro Inoue 1-7-89 Minami Kohoku, Suminoe-ku, Osaka Nichi-Shipbuilding Corporation

Claims (70)

[Claims] 1. Hardly decomposable water, characterized in that the water to be treated is oxidized with ozone in a catalytic oxidation tower in the presence of an oxidation catalyst, and then further oxidized with ultraviolet light and ozone in a promoted oxidation tower. Method for removing a volatile organic compound. 2. The water to be treated is supplied to the catalytic oxidation tower so as to flow upward from the bottom, and the water oxidized in the catalytic oxidation tower is taken out from the top as primary treated water. 2. The method according to claim 1, wherein the water is supplied so as to flow upward from the bottom, and water oxidized in the accelerated oxidation tower is taken out from the top as secondary treated water. 3. The process according to claim 2, wherein a part of the primary treated water is taken out from the top of the catalytic oxidation column and circulated to the bottom of the column. 4. The water to be treated is supplied to the catalytic oxidation tower from the top in a downward flow, and water oxidized in the catalytic oxidation tower is taken out from the bottom as primary treated water. 2. The method according to claim 1, wherein the water is supplied from the top so as to flow downward, and water oxidized in the accelerated oxidation tower is taken out as secondary treated water from the bottom. 5. The method according to claim 4, wherein a part of the primary treated water is taken out from the bottom of the catalytic oxidation tower and circulated to the top of the same. 6. The method according to claim 1, wherein the amount of dissolved ozone at the top of the catalytic oxidation tower is measured, and when the measured value falls below a set value, ozone is supplied to the tower. 7. Ozone is sent from the top of the catalytic oxidation tower to the promoted oxidation tower, and is returned from the promoted oxidation tower to the catalytic oxidation tower again.
The method according to claim 1. 8. The method according to claim 1, wherein an oxidizing agent is previously added to the water to be treated. 9. A catalytic oxidation tower filled with an oxidation catalyst and supplied with ozone, and a promoted oxidation tower provided with an ultraviolet lamp and supplied with ozone, wherein water to be treated is
An apparatus for removing hardly decomposable organic compounds in water, comprising oxidizing with ozone in the presence of an oxidation catalyst in a catalytic oxidation tower, and then oxidizing with an ultraviolet ray and ozone in a promoted oxidation tower. 10. A water inlet is provided at the bottom of the catalytic oxidation tower and the promoted oxidation tower, and a water outlet is provided at the top of the catalytic oxidation tower. The flow of water in the catalytic oxidation tower and the promoted oxidation tower is both upward flow. 10. The device of claim 9, wherein 11. A water inlet is provided at the top of the catalytic oxidation tower and the promoted oxidation tower, and a water outlet is provided at the bottom thereof, so that the water flows in the catalytic oxidation tower and the promoted oxidation tower in a downward flow. 10. The device of claim 9, wherein 12. The apparatus according to claim 9, further comprising a waste ozone treatment device for decomposing waste ozone discharged from the top of the catalytic oxidation tower and / or the promotion oxidation tower. 13. The apparatus according to claim 12, wherein a gas-liquid separation tower is provided between the top of the catalytic oxidation tower and / or the promoted oxidation tower and the waste ozonation apparatus. 14. An oxidizing agent supply device for adding an oxidizing agent to water to be treated in advance.
The device according to any one of claims 13 to 13. 15. The hardly decomposable water, characterized in that the water to be treated is oxidized with ultraviolet light and ozone in a promoted oxidation tower, and then oxidized with ozone in a catalytic oxidation tower in the presence of an oxidation catalyst. Method for removing a volatile organic compound. 16. The water to be treated is supplied to the promoted oxidation tower from the bottom so as to flow upward, water oxidized by the promoted oxidation tower is taken out from the top as primary treated water, and the primary treated water is removed from the catalytic oxidation tower. The method according to claim 15, wherein the water is supplied so as to flow upward from the bottom, and water oxidized in the catalytic oxidation tower is taken out as secondary treated water from the top. 17. The method according to claim 16, wherein a part of the primary treated water is taken out from the top of the catalytic oxidation tower and circulated to the bottom of the same. 18. The water to be treated is supplied to the promoted oxidation tower from the top in a downward flow, water oxidized in the promoted oxidation tower is taken out from the bottom as primary treated water, and the primary treated water is removed from the catalytic oxidation tower. The method according to claim 15, wherein water is supplied from the top so as to flow downward, and water oxidized in the catalytic oxidation tower is taken out as secondary treated water from the bottom. 19. The method according to claim 18, wherein a part of the primary treated water is taken out from the bottom of the catalytic oxidation tower and circulated to the top of the same. 20. The method according to claim 15, wherein the amount of dissolved ozone at the top of the catalytic oxidation tower is measured, and when the measured value falls below a set value, ozone is supplied to the tower. 21. The method according to claim 15, wherein the ozone is sent from the top of the catalytic oxidation tower to the promoted oxidation tower, and further returned from the promoted oxidation tower to the catalytic oxidation tower. 22. The method according to claim 15, wherein an oxidizing agent is added to the water to be treated in advance. 23. A promoting oxidation tower having a built-in ultraviolet lamp and supplied with ozone, and a catalytic oxidation tower filled with an oxidation catalyst and supplied with ozone. And an oxidation treatment with ozone in the catalytic oxidation tower, and then with an ozone in the presence of an oxidation catalyst in a catalytic oxidation tower. 24. A water inlet is provided at the bottom of the promoted oxidation tower and the catalytic oxidation tower, and a water outlet is provided at the top of the promoted oxidation tower and the catalytic oxidation tower. 24. The device of claim 23. 25. A water inlet is provided at the top of the promoted oxidation tower and the catalytic oxidation tower, and a water outlet is provided at the bottom of the promoted oxidation tower and the catalytic oxidation tower. 24. The device of claim 23. 26. The apparatus according to claim 23, further comprising a waste ozone treatment device for decomposing waste ozone discharged from the top of the promotion oxidation tower and / or the catalytic oxidation tower. 27. The apparatus according to claim 26, wherein a gas-liquid separation tower is provided between the top of the catalytic oxidation tower and / or the promoted oxidation tower and the waste ozonation apparatus. 28. The apparatus according to claim 23, further comprising an oxidant supply device for adding an oxidant to water to be treated in advance.
28. The apparatus according to any one of -27. 29. The water to be treated is oxidized with ozone in the catalytic oxidation zone of the oxidation reaction tower in the presence of an oxidation catalyst, and then further oxidized with ultraviolet light and ozone in the accelerated oxidation zone of the tower. A method for removing hardly decomposable organic compounds in water. 30. Water to be treated is supplied to the oxidation reaction tower from the bottom in an upward flow, and water oxidized sequentially in the catalytic oxidation zone on the lower side and the accelerated oxidation zone on the upper side is treated water from the top. 30. The method of claim 29, wherein the method comprises: 31. The method according to claim 30, wherein a part of the treated water is taken out from the top of the oxidation reaction column and circulated to the bottom of the column. 32. Water to be treated is supplied to the oxidation reaction tower from the top in a downward flow, and water oxidized sequentially in the catalytic oxidation zone on the upper side of the tower and the promoted oxidation zone on the lower side is treated from the bottom. 30. The method of claim 29, wherein the method is withdrawn as water. 33. The method according to claim 32, wherein a part of the treated water is taken out from the bottom of the oxidation reaction column and circulated to the top of the column. 34. The method according to claim 29, wherein the amount of dissolved ozone at the top of the oxidation reaction tower is measured, and when the measured value falls below a set value, ozone is supplied to the oxidation reaction tower. 35. The method according to claim 29, wherein the ozone is returned from the top of the oxidation reaction tower to the bottom of the oxidation reaction tower. 36. The method according to claim 29, wherein an oxidizing agent is added to the water to be treated in advance. 37. An oxidation reaction column having a catalytic oxidation zone filled with an oxidation catalyst and an accelerated oxidation zone containing an ultraviolet lamp, wherein ozone is supplied to these zones. An apparatus for removing hardly decomposable organic compounds in water, comprising oxidizing water with ozone in the presence of an oxidation catalyst in a catalytic oxidation zone, and then oxidizing the water with ultraviolet light and ozone in a promotion oxidation zone. 38. A catalytic oxidation zone below the oxidation reaction tower,
A promoted oxidation zone is provided on the upper side, respectively, a water inlet is provided on the bottom of the column, and a water outlet is provided on the top, and the flow of water in the oxidation reaction tower is made to flow upward. 38. The device according to claim 37. 39. A catalytic oxidation zone above the oxidation reaction tower,
A promoted oxidation zone is provided on the lower side, and a water inlet is provided on the top of the tower and a water outlet is provided on the bottom, respectively, so that the flow of water in the oxidation reaction tower is downward. 38. The apparatus of claim 37. 40. The apparatus according to claim 37, further comprising a waste ozone treatment device for decomposing waste ozone discharged from the top of the oxidation reaction tower. 41. The apparatus according to claim 40, wherein a gas-liquid separation tower is provided between the top of the oxidation reaction tower and the waste ozone treatment apparatus. 42. The apparatus according to claim 37, further comprising an oxidant supply device for adding an oxidant to water to be treated in advance.
42. The apparatus according to any one of -41. 43. The water to be treated is oxidized with ultraviolet light and ozone in an accelerated oxidation zone of an oxidation reaction tower, and then oxidized with ozone in the presence of an oxidation catalyst in a catalytic oxidation zone. A method for removing hardly decomposable organic compounds in water. 44. Water to be treated is supplied to an oxidation reaction tower from the bottom so as to flow upward, and water oxidized sequentially in a promoted oxidation zone below the tower and an upper catalytic oxidation zone is treated water from the top. 44. The method of claim 43, wherein the method retrieves 45. The method according to claim 44, wherein a part of the treated water is taken out from the top of the oxidation reaction column and circulated to the bottom of the column. 46. Water to be treated is supplied to the oxidation reaction tower from the top in a downward flow, and the water which has been sequentially oxidized in the promoted oxidation zone on the upper side and the catalytic oxidation zone on the lower side is treated from the bottom. 44. The method of claim 43, wherein the method is withdrawn as water. 47. The method according to claim 46, wherein a part of the treated water is taken out from the bottom of the oxidation reaction tower and circulated to the top of the oxidation reaction tower. 48. The method according to claim 43, wherein the amount of dissolved ozone at the top of the oxidation reaction tower is measured, and when the measured value falls below a set value, ozone is supplied to the oxidation reaction tower. 49. The method according to claim 43, wherein the ozone is returned from the top of the oxidation reaction column to the bottom of the oxidation reaction column. 50. The method according to claim 43, wherein an oxidizing agent is previously added to the water to be treated. 51. An oxidation reaction column having an accelerated oxidation zone containing an ultraviolet lamp and a catalytic oxidation zone filled with an oxidation catalyst, and these zones being supplied with ozone, to be treated. An apparatus for removing hardly decomposable organic compounds in water, comprising oxidizing water with ultraviolet rays and ozone in an accelerated oxidation zone, and then oxidizing water with ozone in the presence of an oxidation catalyst in a catalytic oxidation zone. 52. A promoted oxidation zone below the oxidation reaction tower,
A catalyst oxidation zone is provided on the upper side, a water inlet is provided on the bottom of the column, and a water outlet is provided on the top, respectively, so that the flow of water in the oxidation reaction tower is upward. The device of claim 51. 53. A promoted oxidation zone above the oxidation reaction tower,
A catalytic oxidation zone is provided on the lower side, and a water inlet is provided on the top of the column and a water outlet is provided on the bottom, respectively, so that the flow of water in the oxidation reaction tower is downward. 52. The device of claim 51. 54. The apparatus according to claim 51, further comprising a waste ozone treatment device for decomposing waste ozone discharged from the top of the oxidation reaction tower. 55. The apparatus according to claim 54, wherein a gas-liquid separation tower is provided between the top of the oxidation reaction tower and the waste ozonation apparatus. 56. The apparatus according to claim 51, further comprising an oxidant supply device for adding an oxidant to water to be treated in advance.
The apparatus according to any one of claims 55. 57. A method for removing hardly decomposable organic compounds in water, comprising oxidizing water to be treated with ozone in a catalytic oxidation tower in the presence of an oxidation catalyst. 58. Water to be treated is supplied to the catalytic oxidation tower so as to flow upward from the bottom, ozone is diffused into the tower from the bottom, and water oxidized in the tower is treated as treated water from the top. 58. The method of claim 57, wherein removing. 59. The method according to claim 58, wherein a part of the treated water is taken out from the top of the catalytic oxidation tower and circulated to the bottom of the same. 60. The water to be treated is supplied to the catalytic oxidation tower in a downward flow from the top, ozone is diffused into the tower from the bottom, and the water oxidized in the tower is treated as treated water from the bottom. 58. The method of claim 57, wherein removing. 61. The method according to claim 60, wherein a part of the treated water is taken out from the bottom of the catalytic oxidation tower and circulated to the top of the same. 62. The method according to claim 57, wherein the amount of dissolved ozone at the top of the catalytic oxidation tower is measured, and when the measured value falls below a set value, ozone is supplied to the tower. 63. The method according to claim 57, wherein the ozone discharged from the top of the catalytic oxidation tower is returned to the bottom of the catalytic oxidation tower. 64. The method according to claim 57, wherein an oxidizing agent is added to the water to be treated in advance. 65. A catalytic oxidation tower filled with an oxidation catalyst and supplied with ozone, wherein water to be treated is oxidized with ozone in the tower in the presence of an oxidation catalyst. Removal device for persistent organic compounds. 66. The apparatus according to claim 65, wherein a water inlet is provided at the bottom of the catalytic oxidation tower, and a water outlet is provided at the top of the catalytic oxidation tower, and the flow of water in the tower is upward. 67. The apparatus according to claim 65, wherein a water inlet is provided at the top of the catalytic oxidation tower, and a water outlet is provided at the bottom of the catalytic oxidation tower, and the flow of water in the tower is a downward flow. 68. The apparatus according to claim 65, further comprising a waste ozone treatment device for decomposing waste ozone discharged from the top of the catalytic oxidation tower. 69. The apparatus according to claim 68, wherein a gas-liquid separation tower is provided between the top of the catalytic oxidation tower and the waste ozonation apparatus. 70. The apparatus according to claim 65, further comprising an oxidant supply device for adding an oxidant to water to be treated in advance.
70. The apparatus according to any one of -69.