JP4042275B2 - UV oxidation equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ultraviolet oxidation apparatus that efficiently oxidizes and decomposes a low-concentration organic compound having a low concentration dissolved or suspended in water by mixing an oxidizing agent and irradiating with ultraviolet rays.
[0002]
[Prior art]
As such an ultraviolet oxidizer, an oxidant pressure injection unit and a cross-flow treatment chamber equipped with an ultraviolet lamp are provided in multiple upper and lower stages, and raw water supplied from the bottom, for example, to the left end of the lowermost treatment chamber is supplied to the treatment chamber. After crossflowing to the right, the water is supplied to the inside of the right end of the upper processing chamber from the bottom and crossflowed to the left, thus causing the raw water to meander up and down from the lower processing chamber to the upper processing chamber. An apparatus is known that oxidizes and decomposes dangerous molecules in waste liquid into safe compounds by oxidizing agent injected into the chamber while cross-flowing to the left or right and the light of an ultraviolet lamp irradiated in the chamber.
[0003]
[Problems to be solved by the invention]
In the above conventional apparatus, mixing of the oxidant and irradiation of ultraviolet rays are performed simultaneously in the upper and lower processing chambers. Therefore, when the oxidant is not sufficiently mixed with the raw water, it is irradiated with ultraviolet rays, or when the oxidant is a gas. There is a problem that bubbles are generated by the press-fitting, and the bubbles inhibit ultraviolet light transmission in the raw water, so that the organic compound to be treated cannot be sufficiently oxidized and decomposed.
[0004]
[Means for Solving the Problems]
The present invention has been developed to solve the above-mentioned problems of the conventional apparatus, and the ultraviolet oxidation apparatus of the present invention includes a plurality of parts perpendicular to the bottom surface of the housing inside a hollow rectangular parallelepiped housing. A plurality of processing chambers are formed in the front-rear direction by partitioning in the front-rear direction with a vertical wall, and one side inside each of the odd-numbered processing chambers from the front to the rear among the plurality of processing chambers is irradiated with ultraviolet rays by an ultraviolet lamp. Irradiation part, the other side is divided into an oxidant mixing part having an oxidant supply means at the bottom with a partition wall, and the same side as one side inside each odd-numbered processing chamber inside each even-numbered processing chamber An oxidant mixing unit having an oxidant supply means at the bottom, the other side is partitioned by a partition wall into an ultraviolet irradiation unit, and an ultraviolet irradiation unit and an oxidant mixing unit of each processing chamber are provided at the lower end of the partition wall And communicate with the UV irradiation section of the front and rear processing chambers and acid Agent mixing portion and communicates with the opening provided in the vertical劃壁, raw water is supplied from the upper end to the interior of the oxidizing agent mixing section of the top of the processing chamber, the UV irradiation portion of the tail of the process chamber the process water, the It is characterized by discharging from the upper end of the side opposite to the side where raw water flows into the lower end of the irradiation unit . And in said ultraviolet oxidation apparatus, it is preferable to install in the bottom part of an oxidizing agent mixing part by making an oxidizing agent supply means into an ozone supply means.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Reference numeral 10 denotes a hollow rectangular parallelepiped housing in which a plurality of front and rear processing chambers 12 are formed by being partitioned by a plurality of vertical ridge walls 11 in the front and rear direction. In the illustrated embodiment, the processing chambers are four chambers 12-1, 12-2, 12-3, and 12-4 from front to back, but the number of chambers is arbitrary and dissolved in the raw water. The higher the concentration of the suspended organic compound to be treated, the greater the number of treatment chambers.
[0006]
One side (left in the figure) inside each of the odd-numbered processing chambers 12-1 and 12-3 from the front to the rear among the plurality of processing chambers, the ultraviolet irradiation unit 13 containing the ultraviolet lamp 14, and the other side (FIG. The right) is divided into the oxidant mixing unit 15 containing the oxidant supply means 16 by the partition wall 17 and one side (left in the figure) inside the even-numbered processing chambers 12-2 and 12-4 is oxidized. A partition wall 17 divides the oxidizing agent mixing unit 15 containing the agent supply means 16 and the other side (right side in the figure) into an ultraviolet irradiation unit 13 containing the ultraviolet lamp 14. And the ultraviolet irradiation part 13 and the oxidizing agent mixing part 15 of each process chamber are connected by the opening 18 of the lower end part of the partition wall 17, and the front and back process chambers 12-1 and 12-2, 12-2 and 12- 3, 12-3 and 12-4 of the ultraviolet irradiation unit 13 and the oxidizing agent mixing unit 15 are communicated with each other through the opening 19 at the upper end of the vertical wall 11.
[0007]
The ultraviolet lamps 14 accommodated in the ultraviolet irradiation units 13 of the respective processing chambers are arranged in a plurality of stages in the horizontal direction and in a single row or in a double row in the front-rear direction, and the processing chamber side wall 12 ′ (side wall of the housing) facing the partition wall 17. ) To support. In the figure, the ultraviolet lamps are arranged in an example of meandering in upper and lower stages.
[0008]
The oxidant supply means 16 is an ozone supply means in the illustrated embodiment, and is installed at the bottom of each oxidant mixing section 15. The ozone supplied through the air supply pipe 20 branched from the outside of the housing 10 is used as the water to be treated. Mix.
[0009]
Then, raw water is supplied from the upper end of the front wall of the housing into the oxidizer mixing section 15 of the first processing chamber 12-1 by the supply pipe 21, and treated water is supplied to the rear processing chamber 12-4 by the discharge pipe 22. The ultraviolet irradiation unit 13 is discharged from the upper end of the rear wall of the housing on the side opposite to the side where raw water flows into the lower end of the irradiation unit.
[0010]
When the raw water is supplied from the upper end to the inside of the oxidizer mixing section 15 of the leading treatment chamber 12-1 by the supply pipe 21 by the pump, the raw water flows downward in the mixing section 15 and then the lower end of the partition wall 17. It enters the ultraviolet irradiation unit 13 through the opening 18 and flows upward in the irradiation unit. Then, the processing chamber 12-1 overflows from the opening 19 at the upper end of the vertical partition wall 11 that separates the subsequent processing chamber 12-2 to the upper end of the oxidizing agent mixing section 15 of the processing chamber 12-2. It enters and flows downward, and then enters the ultraviolet irradiation unit 13 through the opening 18 at the lower end of the partition wall of the processing chamber 12-2 and flows upward.
[0011]
In this way, the raw water that has flowed downward through the oxidant mixing unit 15 in the previous processing chamber and flowed into the ultraviolet irradiation unit 13 and then flowed upward in the irradiation unit and then meandered is the oxidant mixing unit in the subsequent processing chamber. By flowing in from the upper end portion, it flows downward and meanders, and this is repeated until the raw water flows into the lower end portion of the irradiation portion of the ultraviolet irradiation portion of the final processing chamber 12-4. It is discharged as treated water from the discharge pipe 22 connected to the upper end of the side opposite to the portion.
[0012]
Accordingly, when ozone gas is supplied to each processing chamber as an oxidant and the ultraviolet lamp is turned on to operate, the raw water flowing downward in the oxidizer mixing section 15 of each processing chamber comes into countercurrent contact with the rising ozone. However, ozone is thoroughly mixed with raw water. The raw water sufficiently mixed with ozone is then irradiated with ultraviolet rays when flowing upward in the ultraviolet irradiation unit 13.
[0013]
The ultraviolet lamp used is preferably a low pressure lamp. This is because the low-pressure ultraviolet lamp has a short wavelength and a strong ability to generate hydroxy radicals. On the other hand, since the wattage is small, it is necessary to increase the number of use for sufficient irradiation. In the present invention, each processing chamber is divided by the partition wall 17 into the oxidant mixing unit 15, the ultraviolet irradiation unit 13, and the like. The volume of the irradiation unit 13 is reduced, and the raw water enters the lower end of one side (or the other side) of the ultraviolet irradiation unit 13 through the opening 18 at the lower end of the partition wall 17 and enters the vertical wall. From the opening 19 on the other side (or one side) upper end of the wall 11 to the overflow of the oxidant mixing unit 15 in the subsequent processing chamber, the irradiation unit 13 flows upward in a diagonal direction to irradiate ultraviolet rays. Therefore, a small number of low-pressure ultraviolet lamps can be used to take advantage of the features. For the same reason, the attachment position of the discharge pipe 22 attached to the ultraviolet irradiation section 13 of the rear processing chamber 12-4 is the side where raw water is injected into the irradiation section from the opening 18 at the lower end of the partition wall 17. It is preferable to use the upper end of the opposite side.
[0014]
The ozone concentration blown into the raw water in the oxidizer mixing section 15 by the ozone supply means is 6 ppm or more so that it can be oxidized even if the low-decomposable organic compound dissolved or suspended in the water has a low concentration. Bubbles generated by the blowing of ozone gas float in the water of the oxidizer mixing unit 15 in each processing chamber and do not enter the ultraviolet irradiation unit 13, and thus adversely affect the irradiation of the ultraviolet lamp in the irradiation unit 13. There is no. The initial raw water supplied to the oxidant mixing unit 15 of the first processing chamber 12-1 may contain oxygen, nitrogen, or other gases, but these bubbles are contained in the mixing unit. It floats and is removed with the rising ozone, and does not adversely affect the ultraviolet irradiation in the ultraviolet irradiation section of each processing chamber thereafter.
[0015]
Using the ultraviolet oxidation apparatus of the illustrated embodiment, water containing 38 ppb nonylphenol, bisphenol A 65 ppb, DDT 2.6 ppb, and estradiol 5.7 ppb, which are suspected of environmental hormones, was treated as raw water. However, the scale of the apparatus is 4 in which the width of the rectangular parallelepiped housing 10 is 2.0 m, the height is 3.5 m, the depth (length in the front-rear direction) is 1.5 m, and the thickness of the processing chamber 12 is 375 mm. The width of the oxidant mixing unit 15 in each chamber and each processing chamber is 375 mm, and the width of the ultraviolet irradiation unit 13 is 1625 mm. Oxygen is supplied to the ozone supply means of each oxidant mixing unit at a rate of 0.9 standing / hour. Was generated at 75 g / hr, and the ozone gas concentration supplied to each oxidizer mixing section was 83 mg / stand. In addition, 48 135 W low-pressure ultraviolet lamps were installed in the ultraviolet irradiation section and installed horizontally at an equal interval of 250 mm in the vertical direction within a height of 3.5 m. The total W number of the ultraviolet lamp is 6480 W. Raw water was supplied to the oxidizer mixing section of the first processing chamber at a flow rate of 1500 standing / hour. The stagnation time in the raw water apparatus was 7 hours.
[0016]
As a result, nonylphenol in the treated water decreased from 38 ppb to 0.2 ppb, bisphenol A from 65 ppb to 0.01 ppb, DDT from 2.6 ppb to 0.1 ppb, and estradiol from 5.7 ppb to 0.0004 ppb.
[0017]
On the other hand, the partition wall 17 that partitions the ultraviolet irradiation unit 13 and the oxidant mixing unit 15 in each processing chamber is removed, and the ultraviolet irradiation unit and the oxidant mixing unit are integrated in each processing chamber. The same apparatus as the illustrated embodiment was used for the structure, and the same raw water was treated under the same conditions for both ozone and ultraviolet rays. As a result, nonylphenol in treated water decreased from 38 ppb to 0.9, bisphenol A decreased from 65 ppb to 0.5 ppb, DDT decreased from 2.6 ppb to 0.8 ppb, and estradiol decreased from 5.7 ppb to 0.5 ppb. It was.
[0018]
【The invention's effect】
According to the present invention, as in claim 1, a plurality of processing chambers are arranged in the front-rear direction by dividing a plurality of processing chambers in the front-rear direction by a plurality of vertical hook walls perpendicular to the bottom surface of the housing. Form one of the plurality of processing chambers from the front to the rear in the odd numbered processing chambers, one side inside the ultraviolet irradiation section by the ultraviolet lamp, and the other side to the oxidizer mixing section having the oxidant supply means at the bottom In addition to partitioning with a partition wall, in each of the even-numbered processing chambers, the same side as one side of each of the odd-numbered processing chambers is an oxidant mixing unit having an oxidant supply means at the bottom, and the other side is irradiated with ultraviolet rays. The partition is partitioned by a partition wall, and the ultraviolet irradiation part and the oxidant mixing part of each processing chamber communicate with each other through an opening provided at the lower end of the partition wall, and the ultraviolet irradiation part and the oxidant mixing part of the front and rear processing chambers Are communicated with each other through an opening provided in the vertical dredging wall, Supplied from the inner to the upper end portion of the agent mixing section, of the UV irradiation portion of the tail of the process chamber the process water, discharged from the upper end portion of the opposite side to the side of raw water to the lower end of the irradiation portion flows by configuring such that, 1) can be completely dissolved in the raw water an oxidizing agent the oxidizing agent countercurrently to the contacted to raw water downflow at oxidizing agent mixing section of the processing chamber, 2) the process In the ultraviolet irradiation section of the chamber, the raw water in which the oxidant is dissolved can flow upward in a diagonal direction so that the ultraviolet rays irradiated by the ultraviolet lamp can be sufficiently bathed without causing a dead space. 3) Oxidant in each processing chamber The raw water is meandered from bottom to top from the mixing section to the ultraviolet irradiation section, and the raw water is meandered from top to bottom from the ultraviolet irradiation section of the previous processing chamber to the oxidizing agent mixing section of the subsequent processing chamber. It can be supplied reasonably without using any other. Furthermore, when the oxidant supply means is an ozone supply means installed at the bottom of the mixing section as in claim 2, the ozone floats up in the downward flowing raw water so as to come into countercurrent contact with the raw water. Since it completely dissolves in water and does not leak into the ultraviolet irradiation section from the opening at the lower end of the partition wall, it does not adversely affect the irradiation of the ultraviolet lamp.
[Brief description of the drawings]
FIG. 1 is a partially cutaway perspective view showing an embodiment of an ultraviolet oxidation apparatus of the present invention.
FIG. 2 is a plan view with the upper wall of the housing of FIG. 1 removed.
3 is a cross-sectional view taken along line III-III in FIG.
4A is a cross-sectional view taken along line AA in FIG. 2, and FIG. 4B is a cross-sectional view taken along line BB in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Housing 11 Vertical wall 12 Processing chamber 13 Ultraviolet irradiation part 14 Ultraviolet lamp 15 Oxidant mixing part 16 Oxidant supply means 17 Partition wall 18 of processing chamber 18 Opening of partition wall 19 Opening of vertical wall 20 Air supply pipe 21 Supply of raw water Pipe 22 Discharge pipe for treated water

Claims (2)

Inside the hollow rectangular parallelepiped housing, a plurality of processing chambers are formed in the front-rear direction by dividing a plurality of vertical chamber walls perpendicular to the bottom surface of the housing in the front-rear direction. The interior of each odd-numbered processing chamber from the rear to the rear is partitioned by an ultraviolet irradiation part using an ultraviolet lamp, and the other side is partitioned by an oxidant mixing part having an oxidant supply means at the bottom, and each even-numbered process Inside the chamber, the same side as the inside of each odd-numbered treatment chamber is divided into an oxidant mixing part having an oxidant supply means at the bottom, and the other side is partitioned by an ultraviolet irradiation part by a partition wall,
The ultraviolet irradiation part and the oxidant mixing part of each of the processing chambers are communicated with each other through an opening provided at the lower end of the partition wall, and the ultraviolet irradiation part and the oxidant mixing part of the front and rear processing chambers are provided on the vertical wall. Communicating at the opening, supplying raw water from the upper end to the inside of the oxidizer mixing section of the first treatment chamber, and supplying the treated water to the lower end of the irradiation section of the ultraviolet irradiation section of the rear treatment chamber An ultraviolet oxidizer characterized by being discharged from the upper end of the side opposite to the part .   2. The ultraviolet oxidizer according to claim 1, wherein the oxidant supply means is an ozone supply means and is installed at the bottom of the oxidant mixing section.

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