JPH10309590A - Water treatment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a water treating rate and to reduce the consumption of an oxidizing agent by using at least one metal element selected from a group of specific metals such as scandium, titanium, vanadium, chromium, copper and zinc. SOLUTION: At least one metal element selected from a group composed of scandium, titanium, vanadium, chromium, copper, zinc, yttrium, zirconium, niobium, molybdenum, technetium, ruthenium, rhodium, silver, cadmium, lanthanum, hafnium, tantalum, tungsten, rhenium, osmium, iridium, platinum, gold, mercury, actinium, thorium, plutoactinium and uranium is used. Titanium, vanadium, chromium, copper, zinc, zirconium or the like is preferable and particularly copper is preferable. The metal can be directly added in a powdery state as the salt of the metal element especially without being restricted. As the result, the oxidation treating reaction is accelerated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water treatment using an oxidizing agent, which is effective for improving the processing speed by using a specific metal and at the same time reducing the running cost by reducing the amount of the oxidizing agent. It concerns a wide range of water treatment methods.

[0002]

2. Description of the Related Art Activated carbon adsorption method, coagulation sedimentation method, activated sludge method and the like are generally used as conventional wastewater treatment containing COD components. However, each of the above-mentioned methods has disadvantages, and the actual situation is that effective wastewater treatment cannot be performed alone. For example, the activated carbon adsorption method has drawbacks in that the treatment cannot be performed effectively with wastewater having a COD concentration of several tens of mg / l or more, and a running cost is expensive, so that activated carbon regeneration equipment is required. The coagulation sedimentation method is a method that is widely used mainly for the purpose of reducing the load on the biological treatment process in the preceding stage of the biochemical treatment method such as the activated sludge method, but in addition to the problem of high running cost, The treatment of generated sludge remains as a major issue. In the biochemical treatment method represented by the activated sludge method, generally, a biodegradable CO is used.
Since it is difficult to decompose the D component, removal of the biodegradable substance or chemical conversion to the readily decomposable substance in the former stage is possible by the combination with the coagulation precipitation method described above or the chemical oxidation method described later. It is a mandatory condition. In addition, there is a problem that it is necessary to treat excess sludge generated in the course of the treatment.

[0003] The common problems of the above-mentioned treatment methods are that when the COD component concentration in the wastewater is high, it is difficult to treat the wastewater, and when the water quality or flow rate of the wastewater fluctuates, it is easily dealt with. There is a point that can not be.

[0004] On the other hand, an oxidation treatment method is known as a chemical method for treating wastewater. This method can be applied even when the COD component concentration in the wastewater is high, and can easily cope with a continuous or discontinuous change in the water quality and flow rate of the wastewater. There are advantages such as not occurring. As the oxidation treatment method, there are an aeration method for efficiently contacting with air, an ozone oxidation method, an oxidation method by injecting an oxidizing agent such as chlorine, hypochlorite, hydrogen peroxide, and the like.

[0005]

However, each of the oxidation treatment methods has a disadvantage that the running cost is significantly higher than other treatment methods. In addition, the above-mentioned oxidation treatment method has the advantage that wastewater treatment of any COD value is possible, as long as the stoichiometric amount of the oxidizing agent used and the treatment time are taken into consideration, but the treatment speed of wastewater is generally low. And running cost (mainly chemicals) are severely restricted, so COD is several tens mg / l.
It has been used only for treatment of wastewater containing a small amount or treatment for the purpose of deodorization or decolorization only, when the load of the oxidation reaction process is small and oxidation treatment in a short time can be applied.

Accordingly, an object of the present invention is to provide a water treatment method which is effective for improving the processing speed of the above-mentioned oxidation treatment method and for reducing running costs by reducing the amount of oxidizing agent and has a wide range of application. And

[0007]

In order to achieve the above object, the present invention has the following arrangement. That is, "in the water treatment using an oxidizing agent, scandium, titanium, vanadium, chromium, copper, zinc, yttrium, zirconium, niobium, molybdenum, technetium, ruthenium,
Use of at least one metal element selected from the group consisting of rhodium, palladium, silver, cadmium, lanthanum, hafnium, tantalum, tungsten, rhenium, osmium, iridium, platinum, gold, mercury, actinium, thorium, protoactinium and uranium. A water treatment method characterized by the above-mentioned. ".

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be specifically described below.

The oxidizing agent used in the present invention can be used in general as long as it is capable of oxidizing organic compounds and metal elements. Examples thereof include a halogen-based oxidizing agent, a peroxide-based oxidizing agent, and ozone. And active oxygen. Oxidizing effects, and preferred oxidizing agents from the viewpoint of economy, chlorine, or hypochlorous acid and its salts, ozone, hydrogen peroxide and the like, particularly preferably chlorine or hypochlorous acid and its salts is there.
These oxidizing agents may be used alone or a plurality of oxidizing agents may be used at the same time. The amount of oxidizer used is
There is no particular limitation because it is determined in consideration of the properties of the water to be treated, the oxidizing agent used, the time constraints required for the treatment, and economic factors.

Next, the metal element used together with the oxidizing agent in the present invention will be described. By the presence of the metal element, the oxidizing ability of the oxidizing agent can be improved, and the processing efficiency can be improved. Scandium, titanium, vanadium,
Chromium, copper, zinc, yttrium, zirconium, niobium, molybdenum, technetium, ruthenium, rhodium, palladium, silver, cadmium, lanthanum, hafnium, tantalum, tungsten, rhenium, osmium,
It must be at least one metal element selected from the group consisting of iridium, platinum, gold, mercury, actinium, thorium, protactinium and uranium,
Preferably, titanium, vanadium, chromium, copper, zinc,
It is at least one metal element selected from the group consisting of zirconium, niobium, molybdenum, rhodium, palladium, silver, cadmium, tungsten, platinum, gold, and mercury, and is particularly preferably copper. The form of the metal element used is not particularly limited, and even in a so-called metal state, any of a metal element oxide, a metal element chloride, a metal element salt, a metal element complex, or a metal element ion It may be in a form. The metal element used may be a single metal element, or a plurality of metal elements may be used simultaneously. The method for adding the metal element is not particularly limited, and the powder of the metal element is added to the water to be oxidized,
The method of directly adding a metal element salt or the like, or the lump containing the above-mentioned metal element, and immersion of a molded product, or a treatment reaction tank, a liquid sending pipe, a liquid sending pump, etc. By using a member containing the metal element, a method of utilizing a metal element eluted from the member into the water to be treated, a method of adding the water containing the metal element to the water to be treated, and the like are effective. Preferably, a method of directly adding a metal element powder or a metal element salt is preferable, and a method of adding a metal element salt to the water to be treated is particularly preferable. The amount of the metal element used is not particularly limited since it varies depending on the form of the metal element used. However, in the case where the metal element is added as a metal element salt, 1 μg / l or more and 100 mg / l or less with respect to the water to be treated. What is necessary is just to use it. More preferably, 10 μg / l or more and 50 mg
/ L or less.

In the present invention, the object to be treated is not limited at all.
D component-containing wastewater and colored wastewater, particularly dye-containing wastewater, are preferred.

Hereinafter, as a specific embodiment of the present invention, an example of an oxidative decoloring treatment of an aqueous dye solution will be described. In addition, Table 1 summarizes the time required until the colorless color was obtained, together with Comparative Examples.
Note that the present invention is not limited to this.

[0013]

【Example】

Example 1 A reactive dye (“Sumifi” manufactured by Sumitomo Chemical Co., Ltd.) was added to pure water.
x supra brill. Red 2BF ") in a solution prepared by dissolving 100 mg / l of copper sulfate (II) pentahydrate at a concentration of 10 mg / l so as to obtain an effective chlorine concentration of 500 mg / l. Sodium was added and left at room temperature.
It was visually confirmed that it became colorless with time.

(Example 2) 100 mg of a reactive dye (“Sumifix supra brill. Red 2BF” manufactured by Sumitomo Chemical) in pure water.
/ L, copper (II) sulfate pentahydrate was dissolved at a concentration of 10 µg / l, and sodium hypochlorite was added at an effective chlorine concentration of 500 mg / l. When left at room temperature, it was visually confirmed that the solution became colorless in 6 hours.

Example 3 100 mg of reactive dye (“Sumifix supra brill. Red 2BF” manufactured by Sumitomo Chemical) in pure water
/ L, to a solution of copper (II) sulfate pentahydrate dissolved at 1 mg / l, sodium hypochlorite was added at an effective chlorine concentration of 100 mg / l. When the mixture was left at room temperature, it was visually confirmed that the mixture became colorless in 2 days.

Comparative Example 1 100 mg of reactive dye (“Sumifix supra brill. Red 2BF” manufactured by Sumitomo Chemical) in pure water.
/ L is added to the solution dissolved to give an effective chlorine concentration of 50 / l.
Sodium hypochlorite was added to a concentration of 0 mg / l. When left at room temperature, it was visually confirmed that the solution became colorless in 8 hours.

(Comparative Example 2) 100 mg of a reactive dye (“Sumifix supra brill. Red 2BF” manufactured by Sumitomo Chemical) in pure water.
/ L dissolved in the solution, the effective chlorine concentration 10
Sodium hypochlorite was added to a concentration of 0 mg / l. When left at room temperature, the color did not completely disappear even after 5 days.

Examples 1 to 3 and Comparative Examples 1 and 2 are summarized in Table 1 below. As is clear from Table 1, the use of the metal together with the oxidizing agent of the present invention has a remarkable effect of accelerating the oxidation treatment reaction.

[0019]

[Table 1]

[0020]

In the water treatment using an oxidizing agent, a water treatment method which is effective and has a wide application range can be used to improve the processing speed by using a specific metal and at the same time to reduce the running cost by reducing the amount of the oxidizing agent used. Can be provided.

Claims (7)

[Claims] In the water treatment using an oxidizing agent, scandium, titanium, vanadium, chromium, copper, zinc, yttrium, zirconium, niobium, molybdenum, technetium, ruthenium, rhodium, palladium, silver, cadmium, lanthanum, hafnium, A water treatment method comprising using at least one metal element selected from the group consisting of tantalum, tungsten, rhenium, osmium, iridium, platinum, gold, mercury, actinium, thorium, protactinium and uranium. 2. The method according to claim 1, wherein the metal element is titanium, vanadium, chromium, copper, zinc, zirconium, niobium, molybdenum, rhodium, palladium, silver, cadmium, tungsten,
The water treatment method according to claim 1, wherein the water treatment method is at least one metal element selected from the group consisting of platinum, gold, and mercury. 3. The water treatment method according to claim 1, wherein the metal is copper. 4. The water treatment method according to claim 1, wherein the oxidizing agent is a halogen-based oxidizing agent. 5. The water treatment method according to claim 1, wherein the oxidizing agent is chlorine or hypochlorite. 6. The water treatment method according to claim 1, wherein the raw water to be treated is colored wastewater. 7. The water treatment method according to claim 1, wherein the raw water to be treated is dye-containing wastewater.