JPS6028884A - Process and apparatus for treating waste water including electrolysis - Google Patents

Abstract

PURPOSE:To decompose org. matters contained in waste water by oxidation with high efficiency and to prevent generation of sludge by performing oxidation treatment of waste water filled in a reaction apparatus by dispersing ozonized gas in the waste water simultaneously with electrolysis and irradiation with ultraviolet rays of the waste water. CONSTITUTION:After regulating concn. and flow rate of ozonized gas by an ozone generator 15 and a flow rate controller 14, the gas is dispersed in the water to be treated through a gas dispersing device 13 having fine pores, and rises upward while keeping contact with the water to be treated and discharged into atmosphere after passing through an exhaust port 16 and a gas absorption tower 17. At the treatment, fixed amt. of raw water to be treated is filled in the reaction tank through an inlet 2 of the raw water at the top of the reaction tank, and samples of treated water are collected appropriately from sampling port 4 while circulating a part of the treated water through circulation passage provided with a circulating pump 6. The treatment is performed while grasping the quality of the treated water, and the treated water is discharged out of an outlet port 3 at the bottom of the reaction tank.

Description

Detailed Description of the Invention The present invention rapidly and effectively oxidizes various organic substances contained in industrial wastewater and urban sewage into carbon dioxide gas and water by using a combination of ozone oxidation method, electrolysis method, and ultraviolet irradiation method. The present invention relates to a treatment method and apparatus for decomposing and minimizing the generation of sludge after treatment.

The ozone oxidation method is one of the oxidation treatment methods, but its biggest advantage is that its oxidizing power at room temperature and pressure is significantly higher than other oxidizing agents, and it uses this strong oxidizing power to sterilize. , deodorization, and phenol conversion are selective, so it is difficult to completely decompose these organic substances into carbon dioxide gas and water, and low molecular weight alcohols, ketones,
Since decomposition stops at saturated fatty acids, these will remain in the treated water. For this reason, attempts have been made to increase the oxidizing power of ozone oxidation by combining it with electrolysis and ultraviolet irradiation. That is, in an electrolytic reaction of an aqueous solution by an electrolytic method, oxygen is generated from the R electrode and hydrogen is generated from the cathode, and the organic substances are oxidized or reduced by these. Furthermore, when salt water is electrolyzed using an insoluble electrode, chlorine is generated at the anode and hydrogen is generated at the cathode. When the electrolyte is sufficiently mixed, the chlorine becomes hypochlorous acid due to a disproportionation reaction. In alkalinity, it becomes chloric acid, so its oxidizing power can also be utilized. Furthermore, it is known that decarbonation occurs through electrolytic oxidation of saturated carboxylic acids, as seen in the Kolbe reaction. Therefore, some of the substances produced by the ozonation reaction undergo a decarboxylation process by electrolytic reaction. Also,
Reactions that use radicals to oxidize and decompose organic matter contained in industrial wastewater, urban sewage, and other wastewater are also being considered. Radicals are active chemical species with an odd number of electrons and are highly reactive, and heat, light, radiation, etc. are used to generate them. It is known that ozone absorbs ultraviolet to visible light and dissociates into highly reactive oxygen atoms and molecules.When irradiated with ultraviolet light using a low-pressure or high-pressure mercury lamp as the irradiation light source, ozone is . l+hV→0. +- 〇★+H,O→2HO- Oxygen atom O" which is highly reactive is generated, which easily reacts with water to become oxidizing radical HO・, and this radical is responsible for the oxidation reaction of organic matter. Can be an initiator.

The present invention utilizes the advantages of the combination of ozone oxidation method and electrolytic method as well as the combination of ozone oxidation method and ultraviolet irradiation method as described above to perform oxidative decomposition of organic matter. DESCRIPTION OF THE PREFERRED EMBODIMENTS The method for treating organic matter according to the present invention using ultraviolet rays will now be described with reference to the accompanying drawings. FIG. 1 is a plan view of a reaction tank according to the present invention, FIG. 2 is a sectional view of the top of the reaction tank, and FIG. 3 is a sectional view of the bottom of the reaction tank. In Fig. 1, (1) is a cylindrical reaction tank, with an electrode support (
7) is installed, and the required number of insoluble anode plates αO)a and cathode plates (10) are installed on this electrode support.
1), and any voltage can be applied to these insoluble electrodes by a power source (8).

Furthermore, an arbitrary inter-electrode distance can be selected by sliding the electrode holder (9) on the electrode support in the direction shown by the arrow in FIG. Further, at the bottom, an ultraviolet lamp (11) connected to a power supply for the ultraviolet lamp (11) and an aeration device θ field are installed. The installation method of this ultraviolet lamp αη and air diffuser (IS) is as follows.
As shown in FIG. 3, there is an ultraviolet lamp 00 in the center, and four air diffusers θ marks are installed concentrically with the ultraviolet lamp 00. After the concentration and flow rate of the ozonized gas are adjusted using an ozone generator and a flow rate regulator (14), it is diffused into the treated water by an aeration device having fine pores and comes into contact with the treated water. While rising, exhaust port (16)
The gas is discharged from the reactor system, and is discharged into the atmosphere through the gas absorption tower Q7). During treatment, a certain amount of raw water to be treated is filled into the reaction tank from the raw water inlet (2) at the top of the reaction tank,
A part of the treated liquid is circulated through a circulation system equipped with a circulation pump (6), and samples are collected as needed (4). The treated water is taken out from the treated water outlet (3).

Next, an example of processing using this processing apparatus will be shown. Ethylene glyco-7 100p as sample wastewater
A pm aqueous solution was used. The raw material gas used to generate ozone was oxygen, and the flow rate of the generated ozonized gas was 51. Am, the concentration is 19 mg/4. The electrolytic method uses ferrite plates (100X 100
x 6) and the current density z 1ty'ay? .

The distance between the electrodes is 3 cm, and in order to add conductivity,
1000 ppm of lPaol was added. A short wavelength UV lamp was used. The treatment was carried out for 3 hours, and
The removal rate of o (total organic carbon) was used as an index of treatment.

In order to compare the effects of these treatment methods, we will examine the combined use of ozone oxidation and electrolytic methods, the combined use of ozone oxidation and ultraviolet irradiation, and the combination of ozone oxidation, electrolytic, and ultraviolet irradiation. went. The processing results are shown in Table 1.

Table 1 As shown in this table, the three single treatment methods
While no decrease in C was observed, in the combined method of ozone oxidation and electrolytic method and the combined method of ozone butylation and ultraviolet irradiation, a decrease in TOO was observed due to the decarbonation of organic matter. However, by simultaneously using the ozone oxidation method, electrolytic method, and ultraviolet irradiation method, an even greater 'roa removal effect was obtained.

As described above, by the simultaneous combined treatment of ozone oxidation method, electrolytic method, and ultraviolet irradiation method according to the present invention, it is possible to efficiently oxidize and decompose organic substances contained in wastewater such as industrial wastewater or urban sewage, and moreover, completely remove the organic matter by decarbonization. Due to decomposition, no sludge is generated after treatment, making it a very effective treatment method.

[Brief explanation of drawings]

FIG. 1 is a plan view of a reaction tank according to the present invention, FIG. 2 is a sectional view of the top of the reaction tank, and FIG. 3 is a sectional view of the bottom of the reaction tank. (1)...Reaction tank, (2)...Raw water inlet, (3)...
... Treated water outlet, (4) ... Sample collection port, (5) ...
・Circulation port, (6)... Circulation pump', (7)... Electrode support, (8)... Power supply, (9)... Electrode holder,
α0)...Insoluble electrode ((10)a...-Anode plate, α
o) b... cathode plate), (9)... ultraviolet lamp, (
b)...Power source for ultraviolet lamp, 0 stage...diffuser,
o4)...Flow control device, (b)...Ozone generator, (16)...Exhaust port, α'? )...Gas absorption tower

Claims (2)

[Claims] (1) When oxidizing and decomposing various organic substances contained in wastewater such as industrial wastewater and urban sewage, a reaction tank equipped with an electrode-ultraviolet lamp and an aeration device is filled with wastewater,
A treatment method that performs electrolytic treatment and ultraviolet irradiation while simultaneously diffusing ozonized gas from an aeration device to perform oxidation treatment. (2) In a device that melts and decomposes various organic substances contained in industrial wastewater, urban sewage, and other wastewater, insoluble electrodes are installed in parallel at the top of the reaction tank, and an ultraviolet lamp and a microscopic electrode are installed at the bottom of the reaction tank. A treatment device equipped with an air diffuser with holes.