KR100465521B1 - Method of treating wastewater using catalytic wet oxidation process - Google Patents

Abstract

A catalytic wet oxidation method is disclosed that is effective for the treatment of hardly degradable organic wastewater. According to this wastewater treatment method, hydrogen peroxide is supplied to the wastewater to be treated as an oxidant and lower temperature and pressure than the conventional catalytic wet oxidation method using Cu (NO ₃ ) ₂ · 3H ₂ O or Cu / Al ₂ O ₃ catalysts. In, for example, dyeing wastewater and domestic sewage can be decomposed at temperatures and atmospheric pressure below 80 ° C.

Description

Method of treating wastewater using catalytic wet oxidation process

The present invention relates to a method for treating wastewater such as dyeing wastewater and domestic sewage, and more particularly, to a wastewater treatment method using a catalytic wet oxidation process.

Dyeing wastewater accounts for more than 18.5% of the wastewater generated by the domestic dye processing industry, and it contains high concentrations of COD components, hardly degradable substances, and color-causing substances, so the wastewater treatment by conventional treatment methods using microorganisms is effective. It is difficult to expect. If not fully treated, the dyeing process wastewater will not only cause aesthetic discomfort by chromaticity but also impede the transmission of sunlight and directly affect the aquatic ecosystem.

In addition, living sewage has been treated mainly by biological methods until now, but for efficient treatment, not only a large site is required but also excessive maintenance costs such as electricity costs are required.

Conventional techniques for decomposing hardly degradable organics include incineration and biological treatment, which is suitable for wastewaters with COD higher than about 100 g / L, but requires a significant amount of fuel and is expensive, and biological treatment is about 20 g with toxic wastewater. It is not suitable for waste waters having COD of / L or more, and there is a problem of generating a large amount of sludge. Therefore, the wet oxidation process is currently best known as a very efficient process for hardly degradable wastewaters having a very low organic matter content for incineration and a very high biological treatment.

However, the conventional wet oxidation process has a typical operating condition of 200 ~ 325 ℃ temperature, 50 ~ 150bar pressure, high temperature and high pressure is required, and there are economic problems such as equipment cost or operation cost of the highly durable device, many performances There was difficulty (Zimmerman, EJ, Chem. Eng., 56 (1958) 117-120).

Therefore, it is urgent to develop a process that can alleviate the harsh reaction operating conditions of the wet oxidation process. Catalytic wet oxidation is well known as a technique for treating toxic wastewater or organic wastewater by injecting a catalyst into the wet oxidation process in order to alleviate the harsh conditions of the conventional wet oxidation process. Catalytic wet oxidation is a treatment method that decomposes organic substances in a liquid reaction condition of 150 to 200 ° C. and 5 to 50 bar using air as an oxidant. At high temperatures and pressures, the high solubility and dispersibility of oxygen are enhanced, so that the reaction rate is increased. By oxidation, the wastewater is finally converted into harmless products such as carbon dioxide and water.

Catalytic wet oxidation has the following advantages over the treatment of dyeing wastewater and domestic sewage compared to other treatment methods.

1. Simultaneous treatment of COD and nitrogen compounds in wastewater is possible, and high efficiency treatment allows direct discharge of treated water or reuse as water.

2. Deodorization and discoloration of waste water are possible.

3. The wastewater to be treated can be applied in a wide range of COD of several thousand ppm to 100,000 ppm.

4. Low energy consumption, low operating cost and low processing cost.

5. It is a continuous operation system with compact device and excellent maintenance.

6. Hazardous gas components are not included in the exhaust gas after treatment.

However, in spite of many of these advantages, the use of oxygen as an oxidant still requires high temperatures in the range of 150 to 200 ° C. and high pressure in the range of 5 to 50 bar.

Accordingly, the present invention is to solve the difficulty of applying the actual process according to the operating conditions of the conventional catalytic wet oxidation process, the catalytic wet oxidation process that can be operated at relatively low temperature and atmospheric pressure by relaxing the existing operating conditions An object of the present invention is to provide a wastewater treatment method.

In addition, an object of the present invention is to provide a wastewater treatment method using a catalytic wet oxidation process that can be applied to dyeing wastewater and domestic sewage treatment in the same way and can expand its application range.

1 is a schematic configuration diagram of an example of a wastewater treatment apparatus suitable for the method of the present invention.

Wastewater treatment method of the present invention for achieving the above object, by using a copper-based catalyst in the catalytic wet oxidation process for treating wastewater and oxidizing hydrogen peroxide as an oxidant to oxidatively decompose organic pollutants in the dyeing wastewater and domestic sewage. At this time, copper nitrate salt (Cu (NO ₃ ) ₂ .3H ₂ O) or Cu / Al ₂ O ₃ is used as a catalyst.

In the present invention, the Cu / Al ₂ O ₃ catalyst may have a form in which a Cu component is supported on Al ₂ O ₃ pellets, and may be prepared by an incipient wetness method. In the initial impregnation method, first, the pores of γ-Al ₂ O ₃ are first saturated with n-hexane so that the copper particles are mainly located on the outer surface of the γ-Al ₂ O ₃ carrier, and then copper (II) Nitrate (Cu (NO ₃ ) _{2. 3} H ₂ O) An appropriate amount of the aqueous solution is injected dropwise into γ-Al ₂ O ₃ . The prepared sample is vacuum dried at 120 ° C. The process is repeated 3 to 5 times so that the supported amount of copper is 10 to 50 weight percent, and finally calcined at 400 ° C. for 4 hours.

And a salt of copper nitrate _{(Cu (NO 3) 2 ·} 3H 2 O) to have the concentration of copper (Cu) can be treated are mixed and dissolved with a dyeing waste water and sewage to be 0.01M when used. At this time, the copper component must be recovered from the treated wastewater.

Hydrogen peroxide (H ₂ O ₂ ) used as an oxidant in the present invention can be removed by oxidizing the organic contaminants more easily the higher the concentration and the higher the mixing ratio with the waste water. However, since the catalyst according to the present invention is used, an aqueous solution having a concentration of about 18% (V / V) may have a desirable effect only by using about 1/1000 of the wastewater.

In the present invention, the wastewater can be treated with a considerable efficiency in the temperature range of 20 to 100 ° C., which includes atmospheric pressure and room temperature, which is lower than the conventional treatment temperature and pressure, and in practical terms, the temperature range of atmospheric pressure and 30 to 80 ° C. have. The optimum temperature expected for performance is 80 ° C. For example, at 100 ° C., the decomposition efficiency is somewhat lowered because the concentration of oxygen that can be saturated in water at normal pressure is small. The pressure is maintained at 1 atm while the reaction is in progress. Higher pressures require the use of a high pressure reactor, which increases the equipment cost and operating cost of the reactor, resulting in economic difficulties.

1 is a schematic configuration diagram of an example of a wastewater treatment apparatus suitable for the method of the present invention. Hereinafter, a process in which the wastewater treatment method using the catalytic wet oxidation of the present invention will be described with reference to FIG. 1. The wastewater treatment apparatus includes a wastewater injection pipe having a wastewater injection pump 11, a hydrogen peroxide injection pipe having a hydrogen peroxide injection pump 21, a reactor 15 prepared with a catalyst for catalytic wet oxidation of wastewater, A drain pipe for discharging the treated wastewater, a gas / liquid separator 23 provided on the drain pipe, and a heat exchanger 13 in which the waste water injection pipe and the drain pipe cross-contact each other.

Waste water to be treated in this apparatus is first introduced into the reactor 15 through the wastewater injection pipe in the wastewater storage tank 10. In the wastewater injection pipe, the wastewater is forcibly supplied to the reactor 15 by the wastewater injection pump 11 and passes through the heat exchanger 13 on the path. The heat exchanger 13 is configured to be in contact with a large area while the wastewater injection pipe and the treated wastewater pipe are crossed. Therefore, the wastewater to be treated is subjected to heat exchange with the treated wastewater which has passed through the reactor 15. Wastewater Treatment The oxidation reaction is usually exothermic, so the treated wastewater is at a temperature higher than room temperature and cooling is required for discharge, and the wastewater introduced into the reactor for process efficiency is preferably higher than room temperature.

The reactor 15 may be provided with a temperature controller 17 having a heater and a temperature sensor to maintain a constant temperature condition. The catalyst support layer in the reactor 15 is filled with a Cu / Al ₂ O ₃ catalyst. In addition, an 18% (V / V) aqueous hydrogen peroxide aqueous solution used as an oxidant is introduced into the reactor 15 together with the wastewater through a valve and a metering pump 21 in a reservoir 19. Thus, the wastewater injected into the reactor 15 is mixed with hydrogen peroxide and brought into contact with the catalyst through the catalyst bed. On the surface of the catalyst, hydrogen peroxide water supplied to the oxidant is activated to rapidly generate high oxidative radical hydroxide (· OH) to easily oxidatively decompose organic pollutants contained in the water. The catalyst also serves to adsorb organic contaminants, so that the organic contaminants adsorbed on the catalyst react more easily with the radicals produced on the catalyst surface.

The wastewater treated while passing through the reactor 15 is cooled by the wastewater flowing into the reactor 15 and the heat exchanger 13 and then sent to the gas / liquid separator 23. The wastewater treated with the gas discharged from the gas / liquid separator 23 is finally discharged.

Hereinafter, the present invention will be described in detail through various embodiments of the present invention, and the efficiency in each of them will be described.

(Example 1)

After filling 300g of Cu / Al ₂ O ₃ catalyst with 30% copper content at 1 atmosphere and 80 ℃, dark red color with total organic carbon (TOC) concentration of 1890mg / L and chromaticity of 3150 degrees Dyeing wastewater was injected. The flow rate of the injected wastewater was 20 L / min. The flow rate of the injected 18% (V / V) hydrogen peroxide water was 1/1000 of the wastewater flow rate. After passing through the catalyst-filled reactor, the total organic carbon concentration of the wastewater was 5.6 mg / L, and more than 99.7% of total organic carbon was removed, and the chromaticity was 6.1 degrees and more than 99.8%.

(Comparative Example 1)

All the conditions were the same as in the example, but the experiment was performed in a state in which the Cu / Al ₂ O ₃ catalyst was not filled at all. The total organic carbon concentration of the wastewater passed through the catalyst-free reactor was 1860 mg / L, and only about 1.5% of the total organic carbon was removed, and the chromaticity was 2995 degrees and less than 5%.

(Example 2)

The same conditions as in Example 1 and the case where the flow rate of the wastewater was 50 L / min. After passing through the catalyst-filled reactor, the total organic carbon concentration of the wastewater was 37 mg / L, about 98% of the total organic carbon was removed, and the color was removed at 56 degrees and more than 98.2%.

(Comparative Example 2)

All the conditions were the same as in Example 2, but the experiment was carried out in a state without filling the Cu / Al ₂ O ₃ catalyst. The total organic carbon concentration in the wastewater that passed through the catalyst-free reactor was 1885 mg / L, and the total organic carbon was hardly removed and only 1% of the chromaticity was 3120 degrees.

(Example 3)

The same conditions as in Example 1 or when 600g of Cu / Al ₂ O ₃ catalyst having a copper content of 30% is filled. After the catalyst-packed reactor, the total organic carbon concentration in the wastewater was 3.0 mg / L and the chromaticity was 3.2 degrees.

(Comparative Example 3)

The experiment was carried out under the same conditions as in Example 3 or without any catalyst. Experimental results showed similar values to Comparative Example 1. Only less than 1.5% total organic carbon and less than 5% chromaticity have been removed.

(Example 4)

The same conditions as in Example 2 or 600g of Cu / Al ₂ O ₃ catalyst having a copper content of 30%. After passing through the catalyst-filled reactor, the total organic carbon concentration of the wastewater was 6.4 mg / L, the color was 6.8 degrees, and 99.7% of total organic carbon and more than 99.5% of color were removed.

(Comparative Example 4)

The same conditions as in Example 4 or when no catalyst was used at all. After treatment, the total organic carbon concentration in wastewater was hardly removed at 1884 mg / L, and the chromaticity was less than 1% at 3122 degrees.

Examples 1 to 4 and Comparative Examples 1 to 4 can be summarized as shown in Table 1 below. In the state of the catalyst used in Table 1 s means solid.

Occation Reaction temperature (℃) Injection Wastewater Flow Rate (L / min) Hydrogen Peroxide Flow Rate for Wastewater Flow Catalyst used (state) Catalyst filling amount (g) Catalyst Copper Content (%) TOL removal rate after reaction (%) Color removal rate after reaction (%) Example 1 80 20 1/1000 Cu / Al ₂ O ₃ (s) 300 30 99.7 99.8 Comparative Example 1 80 20 1/1000 · · 30 1.5 5 Example 2 80 50 1/1000 Cu / Al ₂ O ₃ (s) 300 30 98 98.2 Comparative Example 2 80 50 1/1000 · · 30 0 One Example 3 80 20 1/1000 Cu / Al ₂ O ₃ (s) 600 30 99.9 99.9 Comparative Example 3 80 20 1/1000 · · 30 1.5 5 Example 4 80 50 1/1000 Cu / Al ₂ O ₃ (s) 600 30 99.7 99.5 Comparative Example 4 80 50 1/1000 · · 30 0 One

From the above examples and comparative examples, if the flow rate of the wastewater and the filling amount of the catalyst are properly adjusted, that is, if the flow rate of the wastewater is high (when the capacity of the wastewater to be treated is large), the filling amount of the catalyst is increased to 99.5% or more of total organic carbon and It can be seen that color can be removed.

The following examples show the results according to the reaction temperature.

(Example 5)

It is a case where the conditions and reaction temperature similar to Example 1 are 50 degreeC. After passing through the catalyst-filled reactor, the total organic carbon concentration of wastewater was 12.3 mg / L, and more than 99.4% of total organic carbon was removed, and the color was 22.4 degrees and more than 99.3% of color was removed.

(Example 6)

It is a case where the conditions and reaction temperature similar to Example 1 were made into 30 degreeC. After the catalyst-filled reactor, the total organic carbon concentration of the wastewater was 134.5 mg / L, and about 92.9% of total organic carbon was removed, and the color was removed by 89.2 degrees and about 97.2%.

Comparing Example 1, Example 5 and Example 6 it can be seen that as the reaction temperature is lowered, the removal efficiency of total organic carbon and color decreases.

The following examples increase the amount of catalyst used or the flow rate of hydrogen peroxide water to overcome the reduction in total organic carbon and chromaticity removal rate as the reaction temperature decreases.

(Example 7)

The same conditions as in Example 5 and the case where the flow rate of the injected 18% (V / V) hydrogen peroxide water was 2/1000 of the wastewater flow rate. After passing through the catalyst-filled reactor, total organic carbon in wastewater was 5.4 mg / L, and more than 99.7% of total organic carbon was removed, and the chromaticity was 6.0 degrees and more than 99.8%. After all, even if the reaction temperature of 80 ℃ to 50 ℃ to increase the flow rate of hydrogen peroxide water can be obtained the total organic carbon and color removal efficiency at the 80 ℃ reaction temperature.

(Example 8)

The same conditions as in Example 5 or 600g of Cu / Al ₂ O ₃ catalyst having a copper content of 30%. After passing through the catalyst-filled reactor, the total organic carbon of the wastewater was 3.9 mg / L, and more than 99.8% of total organic carbon was removed, and the chromaticity was 5.3 degrees and more than 99.8%. After all, even if the reaction temperature is lowered, increasing the amount of catalyst used may increase the removal efficiency of total organic carbon and color.

(Example 9)

In the same conditions as in Example 5, 400g of Cu / Al ₂ O ₃ catalyst having a copper content of 30% was charged, and the flow rate of 18% (V / V) hydrogen peroxide water was 1.5 / 1000 of the wastewater flow rate. The total organic carbon concentration of the wastewater passed through the reactor was 5.4 mg / L, the chromaticity was 6.2 degrees, and the high removal efficiency was obtained despite the reaction temperature of 50 ° C.

(Example 10)

The same conditions as in Example 6 were performed when the flow rate of the injected 18% (V / V) hydrogen peroxide water was 2/1000 and 600 g of a Cu / Al ₂ O ₃ catalyst having a copper content of 30% was charged. The total organic carbon concentration of the wastewater passed through the reactor was 9.4 mg / L and the chromaticity of 15.4 degrees was removed by 99.5% and 99.5%, respectively.

In view of the results of Examples 7 to 10 above, even if the reaction temperature is lowered to 50 ° C and 30 ° C, increasing the amount of catalyst used and the flow rate of hydrogen peroxide can achieve similar results to the removal efficiency at 80 ° C. It can be seen.

(Example 11)

The result is the same as in Example 1 or when 300 g of a Cu / Al ₂ O ₃ catalyst containing 50% copper is charged. The total organic carbon concentration of the wastewater that passed through the catalyst-filled reactor was 4.4 mg / L, and more than 99.8% of total organic carbon was removed, and the chromaticity was 5.2 degrees and more than 99.8%.

(Example 12)

The result is the same as in Example 1 or when 300 g of a Cu / Al ₂ O ₃ catalyst containing 10% copper is charged. The total organic carbon concentration of the wastewater that passed through the catalyst-filled reactor was 10.2 mg / L, which removed about 99.5% of total organic carbon and about 99.6% of chromaticity.

Comparing Example 1, Example 11 and Example 12 as described above, as the copper content of the Cu / Al ₂ O ₃ catalyst increases, the removal efficiency of the total organic carbon and chromaticity increased. However, even if the copper content is different, the use of Cu / Al ₂ O ₃ catalyst can effectively remove more than 95% of total organic carbon and color of waste water.

(Example 13)

Instead of using 300 g of Cu / Al ₂ O ₃ catalyst having the same conditions as in Example 1 or 300% of copper, Cu (NO ₃ ) ₂ .3H ₂ O was mixed with the wastewater so that the concentration of Cu was 0.01 M. It is the result of dissolving wastewater. The total organic carbon concentration of the wastewater after passing through the reactor not filled with the Cu / Al ₂ O ₃ catalyst was 4.2 mg / L, and more than 99.8% of total organic carbon was removed, and the chromaticity was 5.0 degrees and more than 99.8%. As a result, a similar wastewater treatment effect can be obtained by using Cu (NO ₃ ) ₂ · 3H ₂ O instead of Cu / Al ₂ O ₃ as a solid catalyst. However, if Cu (NO ₃ ) ₂ · 3H ₂ O is used, a separation process must be followed to remove Cu from the treated water prior to discharge of the treated wastewater.

Examples 5 to 13 are summarized in Table 2 below. Ac in the state of the catalyst used in Table 2 means an aqueous solution state.

Occation Reaction temperature (℃) Injection Wastewater Flow Rate (L / min) Hydrogen Peroxide Flow Rate for Wastewater Flow Catalyst used (state) Catalyst filling amount (g) Catalyst copper content (%) TOL removal rate after reaction (%) Color removal rate after reaction (%) Example 5 50 20 1/1000 Cu / Al ₂ O ₃ (s) 300 30 99.4 99.3 Example 6 30 20 1/1000 Cu / Al ₂ O ₃ (s) 300 30 92.9 89.2 Example 7 50 20 2/1000 Cu / Al ₂ O ₃ (s) 300 30 99.7 99.8 Example 8 50 20 1/1000 Cu / Al ₂ O ₃ (s) 600 30 99.8 99.8 Example 9 50 20 1.5 / 1000 Cu / Al ₂ O ₃ (s) 400 30 99.9 99.9 Example 10 30 20 2/1000 Cu / Al ₂ O ₃ (s) 600 30 99.5 99.5 Example 11 80 20 1/1000 Cu / Al ₂ O ₃ (s) 300 50 99.8 99.8 Example 12 80 20 1/1000 Cu / Al ₂ O ₃ (s) 300 10 99.5 99.6 Example 13 80 20 1/1000 Cu / (NO ₃ ) _{2 3} H ₂ O (ac) 0.01M 99.8 99.8

The following examples are the results of experiments using living sewage generated in the city. Household sewage was used for the experiment after the first precipitation and flocculation treatment.

(Example 14)

Municipal sewage with an initial chemical oxygen demand (COD, hereinafter referred to as COD) of 128.6 mg / L was treated under the same conditions as in Example 1. After passing through the catalyst-filled reactor, the COD of the treated water was removed at more than 96% as 4.1 mg / L.

(Example 15)

Municipal sewage with an initial COD of 128.6 mg / L was treated under the same conditions as in Example 2. After passing through the catalyst-filled reactor, the COD of the treated water was 8.4 mg / L, which was more than 93% removed.

(Example 16)

It is the result of treating the municipal sewage which is initial COD 128.6mg / L under the same conditions as Example 3. After passing through the catalyst-packed reactor, the COD of the treated water was 2.1 mg / L, which was removed by more than 98%.

(Example 17)

This is the result of treating living sewage with initial COD of 128.6 mg / L under the same conditions as in Example 4. After passing through the catalyst-filled reactor, the COD of the treated water was 6.0 mg / L, which was removed by more than 95%.

(Example 18)

When the same conditions and reaction temperature as in Example 1, 50 ℃ is the result of treatment of domestic sewage with an initial COD of 109.9 mg / L. The COD of the treated water was 10.2 mg / L and more than 90% was removed.

(Example 19)

When the same conditions and reaction temperature as in Example 1 is 30 ℃ is the result of treatment of domestic sewage with an initial COD of 109.9 mg / L. After the reactor, the COD of the treated water was 18.2 mg / L, about 83% of which was removed.

(Example 20)

The same conditions as in Example 18 or the flow rate of the injected 18% (V / V) hydrogen peroxide water were 2/1000 of the wastewater flow rate. When the sewage with an initial COD of 110.4 mg / L was passed through the reactor, the COD of the treated water was 8.3 mg / L, which was about 93% removed.

(Example 21)

The same conditions as in Example 18 or 600g of Cu / Al ₂ O ₃ catalyst having a copper content of 30%. When sewage with an initial COD of 112.4 mg / L was passed through the reactor, the COD of the treated water was 5.9 mg / L, which was more than 95% removed.

(Example 22)

The same conditions as in Example 18 or 400 g of a Cu / Al ₂ O ₃ catalyst having a copper content of 30% were charged, and the flow rate of 18% (V / V) hydrogen peroxide water was 1.5 / 1000 of the wastewater flow rate. When the sewage with an initial COD of 113.6 mg / L was passed through the reactor, the COD of the treated water was 6.7 mg / L, which was about 94% removed.

(Example 23)

The same conditions as in Example 19 were performed when the flow rate of the injected 18% (V / V) hydrogen peroxide water was 2/1000 and 600 g of a Cu / Al ₂ O ₃ catalyst having a copper content of 30% was charged. When the municipal sewage with an initial COD of 127.6 mg / L was passed through the reactor, the COD of the treated water was 10.4 mg / L and more than 90% was removed.

(Example 24)

The result is the same as in Example 14 or when 300 g of a Cu / Al ₂ O ₃ catalyst having a copper content of 50% is charged. The initial COD of domestic sewage was 131.6 mg / L, and after passing through the catalyst-filled reactor, the COD of the treated water was 2.7 mg / L, which was about 98% removed.

(Example 25)

The result is the same as in Example 14 or when 300 g of a Cu / Al ₂ O ₃ catalyst containing 10% copper is charged. After the municipal sewage with an initial COD concentration of 128.4 mg / L was passed through the catalyst-filled reactor, the COD of the treated water was 9.5 mg / L, which was removed by 93%.

(Example 26)

Instead of using 300 g of a Cu / Al ₂ O ₃ catalyst having the same conditions as in Example 14 or 300% of copper, the copper nitrate of Cu (NO ₃ ) ₂ · 3H ₂ O was depleted so that the concentration of Cu was 0.01M. This is the result of treatment of domestic sewage by mixing and dissolving in water. Treatment of municipal sewage with an initial COD of 120.6 mg / L resulted in more than 97% COD of 3.5 mg / L.

Examples 14 to 26 are summarized in Table 3 below.

Occation Reaction temperature (℃) Injection Wastewater Flow Rate (L / min) Hydrogen Peroxide Flow Rate for Wastewater Flow Catalyst used (state) Catalyst filling amount (g) Catalyst Copper Content (%) COD removal rate after reaction (%) Example 14 80 20 1/1000 Cu / Al ₂ O ₃ (s) 300 30 96 Example 15 80 50 1/1000 Cu / Al ₂ O ₃ (s) 300 30 93 Example 16 80 20 1/1000 Cu / Al ₂ O ₃ (s) 600 30 98 Example 17 80 50 1/1000 Cu / Al ₂ O ₃ (s) 600 30 95 Example 18 50 20 1/1000 Cu / Al ₂ O ₃ (s) 300 30 90 Example 19 30 20 1/1000 Cu / Al ₂ O ₃ (s) 300 30 83 Example 20 50 20 2/1000 Cu / Al ₂ O ₃ (s) 300 30 93 Example 21 50 20 1/1000 Cu / Al ₂ O ₃ (s) 600 30 95 Example 22 50 20 1.5 / 1000 Cu / Al ₂ O ₃ (s) 400 30 94 Example 23 30 20 2/1000 Cu / Al ₂ O ₃ (s) 300 30 90 Example 24 80 20 1/1000 Cu / Al ₂ O ₃ (s) 300 50 98 Example 25 80 20 1/1000 Cu / Al ₂ O ₃ (s) 300 10 93 Example 26 80 20 1/1000 Cu / (NO ₃ ) _{2 3} H ₂ O (ac) 0.01M 93

As can be seen from the examples of dyeing wastewater and domestic sewage, the use of Cu / Al ₂ O ₃ catalyst and Cu (NO ₃ ) ₂ · 3H ₂ O catalyst with hydrogen peroxide can effectively decompose wastewater. Could know.

According to the present invention, in the case of the dye wastewater, more than 95% of total organic carbon and color could be removed, and in the case of domestic sewage, more than 90% of COD could be removed by effectively controlling catalyst usage, hydrogen peroxide usage and temperature.

As shown in the above results, according to the present invention, when Cu (NO ₃ ) ₂ · 3H ₂ O and Cu / Al ₂ O ₃ are used as the catalyst and H ₂ O ₂ is used as the oxidizing agent, 1 atmosphere and a low temperature (30 to 80 ° C.) are used. ) Was able to effectively treat dyeing wastewater and domestic sewage. In particular, the treatment efficiency is much higher than that of the existing biological treatment method, so that a small-sized facility can be installed on a small site. In addition, the process itself can be easily automated, there is an advantage that can be operated without professional personnel.

Claims (7)

delete delete In the method of treating dyeing wastewater or domestic sewage wastewater, Injecting hydrogen peroxide as oxidant into the wastewater; Contacting the waste water to which the oxidant is added with a Cu / Al ₂ O ₃ catalyst, In the Cu / Al ₂ O ₃ catalyst, the pores of the γ-Al ₂ O ₃ carrier were first saturated with n-hexane, followed by injecting an aqueous solution of Copper (II) Nitrate (Cu (NO ₃ ) ₂ · 3H ₂ O), followed by vacuum. Repeating the drying process so that the supported amount of copper to 10 to 50% by weight, and formed by the initial impregnation method to be fired at 400 ℃ or more, wastewater treatment method using a catalytic wet oxidation process. delete The method of claim 3, wherein The hydrogen peroxide solution (H ₂ O ₂ ) is a wastewater treatment method using a catalytic wet oxidation process, characterized in that using an aqueous solution having a concentration of 18% (V / V) at a ratio of 1/1000 of the waste water. The method of claim 3, wherein The step of contacting the waste water with the Cu / Al ₂ O ₃ catalyst wastewater treatment method using a catalytic wet oxidation process, characterized in that the pressure is carried out in the normal pressure and temperature conditions 20 to 100 ℃ range. The method of claim 6, The step of contacting the waste water with the Cu / Al ₂ O ₃ catalyst wastewater treatment method using a catalytic wet oxidation process, characterized in that the pressure is carried out in the normal pressure and temperature conditions 30 to 80 ℃ range.