JP2023160583A - Organic matter decomposition method and its apparatus - Google Patents

Abstract

To provide an organic matter decomposition treatment method and its apparatus capable of reducing the cost of decomposing organic matter as much as possible, compared to decomposing organic matter by adding water peroxide to a treated liquid containing organic matter and bringing that the treated liquid into contact with a catalyst.SOLUTION: In the organic matter decomposition method of the present invention, hydrogen peroxide and nitric acid are added to a treated liquid containing organic matter, and the treated liquid is brought into contact with a catalyst. In the organic matter decomposition method of the present invention, the temperature of the treated liquid after adding the hydrogen peroxide and nitric acid is suitably within the range of 0°C to 200°C.SELECTED DRAWING: Figure 1

Description

The present invention relates to an organic matter decomposition method and an organic matter decomposition device.

In the past, ``organohalogen compound characterized by heating an organic halogen compound from 100°C to 200°C in the presence of a catalyst consisting of copper oxide and hydrogen peroxide to perform a hydrothermal oxidation reaction using the Fenton method. A method for decomposing a compound has been proposed (see, for example, Publication No. 2014/080739).

Re-table 2014/080739 publication

By the way, when using the decomposition treatment method described above to sufficiently decompose organic substances in the liquid to be treated (for example, organic substances such as 1,4-dioxane, which is subject to the PRTR system), a large amount of It was necessary to add hydrogen peroxide and then bring the treated liquid into contact with the catalyst. For this reason, the above-described decomposition treatment method has a problem in that the cost for decomposing organic matter increases.

An object of the present invention is to reduce the cost of decomposing organic matter as much as possible compared to the case where hydrogen peroxide is added to a liquid to be treated containing organic matter and the liquid to be treated is brought into contact with a catalyst to decompose the organic matter. An object of the present invention is to provide a decomposition treatment method and an organic substance decomposition device.

In the organic substance decomposition method according to the first aspect of the present invention, hydrogen peroxide and nitric acid are added to a liquid to be treated containing organic substances, and the liquid to be treated is brought into contact with a catalyst. Examples of organic substances include 1,4-dioxane, which is subject to the PRTR system. The catalyst is, for example, a Fenton catalyst (eg, an iron compound such as ferrous sulfate, a copper compound such as copper oxide, a mixture of copper and a metal element other than copper (eg, nickel, etc.)).

As a result of intensive studies by the inventors of the present application, by adding not only hydrogen peroxide but also nitric acid to the liquid to be treated containing organic matter, a smaller amount of hydrogen peroxide can be used than would be required if nitric acid was not added. It was revealed that the organic matter decomposition ability was equivalent to or higher than that without adding nitric acid. The price of hydrogen peroxide and nitric acid when nitric acid is added is lower than the price of hydrogen peroxide when nitric acid is not added. Therefore, in this method of decomposing organic matter, the cost for decomposing organic matter can be kept as low as possible compared to the case where hydrogen peroxide is added to the liquid to be treated containing organic matter and the liquid to be treated is brought into contact with a catalyst to decompose the organic matter. I can do it.

The organic substance decomposition method according to the second aspect of the present invention is the organic substance decomposition method according to the first aspect, wherein the temperature of the liquid to be treated after adding hydrogen peroxide and nitric acid is in the range of 0°C to 200°C. It is within.

As a result of intensive studies by the inventors of the present application, organic matter can be decomposed without deactivating the catalyst by keeping the temperature of the liquid to be treated after adding hydrogen peroxide and nitric acid within the range of 0°C to 200°C. It has become clear that it is possible to further promote

The organic matter decomposition device according to the third aspect of the present invention includes a first supply section and a second supply section. The first supply unit supplies a liquid to be treated containing organic matter to the catalyst. The second supply unit supplies hydrogen peroxide and nitric acid to the liquid to be treated before the liquid to be treated reaches the catalyst.

As a result of intensive studies by the inventors of the present application, by adding not only hydrogen peroxide but also nitric acid to the liquid to be treated containing organic matter, a smaller amount of hydrogen peroxide can be used than would be required if nitric acid was not added. It was revealed that the organic matter decomposition ability was equivalent to or higher than that without adding nitric acid. The price of hydrogen peroxide and nitric acid when nitric acid is added is lower than the price of hydrogen peroxide when nitric acid is not added. Therefore, in this organic matter decomposition device, the cost for decomposing organic matter can be kept as low as possible compared to the case where hydrogen peroxide is added to the liquid to be treated containing organic matter and the liquid to be treated is brought into contact with a catalyst to decompose the organic matter. I can do it.

The organic matter decomposition device according to the fourth aspect of the present invention is the organic matter decomposition device according to the third aspect, and further includes a reactor. In the reactor, the catalyst is immobilized. Moreover, the outlet of the first supply section is connected to the inlet of the reactor. The second supply section has an outlet connected to the first supply section.

According to the above configuration, the catalyst is fixed in the reactor. Therefore, in this organic matter decomposition device, it is possible to continuously perform the decomposition treatment of organic matter contained in the liquid to be treated.

The organic matter decomposition device according to the fifth aspect of the present invention is the organic matter decomposition device according to the fourth aspect, and further includes a heating section. The heating section heats at least one of the first supply section, the second supply section, and the reactor.

According to the above configuration, decomposition of organic matter can be promoted.

The organic matter decomposition device according to the sixth aspect of the present invention is the organic matter decomposition device according to the fifth aspect, wherein the heating section is in a state where the liquid to be treated after adding hydrogen peroxide and nitric acid is in contact with the catalyst. At least one of the first supply section, the second supply section, and the reactor is heated so that the temperature of the liquid to be treated is within the range of 0° C. or higher and 200° C. or lower.

According to the above configuration, the decomposition of organic matter can be further promoted without deactivating the catalyst.

FIG. 1 is a front view of an organic matter decomposition device according to an embodiment of the present invention. FIG. 1 is a left side view of an organic matter decomposition device according to an embodiment of the present invention. FIG. 1 is a right side view of an organic matter decomposition device according to an embodiment of the present invention. FIG. 1 is a rear view of an organic matter decomposition device according to an embodiment of the present invention.

<Description of organic substance decomposition method according to embodiment of the present invention>
In the organic substance decomposition method according to the embodiment of the present invention, hydrogen peroxide and nitric acid are added to a liquid to be treated containing organic substances, and the liquid to be treated is brought into contact with a catalyst. For example, a catalyst is put into a container containing a liquid to be treated after adding hydrogen peroxide and nitric acid, or a liquid to be treated after adding hydrogen peroxide and nitric acid is allowed to flow into a container containing a catalyst. By doing so, the liquid to be treated after adding hydrogen peroxide and nitric acid can be brought into contact with the catalyst. Organic matter is decomposed by the liquid to be treated after adding hydrogen peroxide and nitric acid coming into contact with a catalyst. Examples of organic substances include 1,4-dioxane, 1,3-dioxolane, 1,2-dichloroethane, 1,1-dichloroethylene, dichloromethane, chloroform, 1,1,1-trichloroethane, and 1,1-dichloroethane, which are subject to the PRTR system. , 2-trichloroethane, carbon tetrachloride, 1,2-dichloropropane, 1,3-dichloropropene, bromodichloromethane, trichloroethylene, tetrachloroethylene, trichlorobenzene, dichlorobenzene, dioxins, 1,2-epoxybutane, chlorodifluoromethane, These include 1-chloro-1,1-difluoroethane, perfluoro, phenol, N,N-dimethylformamide, formaldehyde, and toluene. The catalyst is, for example, a Fenton catalyst (eg, an iron compound such as ferrous sulfate, a copper compound such as copper oxide, a mixture of copper and a metal element other than copper (eg, nickel, etc.)). In addition, in the organic matter decomposition method according to the embodiment of the present invention, the temperature of the liquid to be treated after adding hydrogen peroxide and nitric acid is preferably within the range of 0°C or more and 200°C or less, and preferably 50°C or more. It is more preferably within the range of 200°C or less, more preferably within the range of 100°C or more and 200°C or less, even more preferably within the range of 150°C or more and 200°C or less, and 180°C or more and 200°C It is particularly preferable that it is within the following range.

When decomposing organic matter contained in a liquid to be treated using the organic matter decomposition method according to the embodiment of the present invention, it is preferable to use an organic matter decomposition apparatus 1 shown in FIGS. 1 to 4. The organic matter decomposition device 1 will be explained below.

<Configuration of an organic matter decomposition device according to an embodiment of the present invention>
As shown in FIGS. 1 to 4, the organic matter decomposition apparatus 1 mainly includes a liquid distribution section 100, an additive liquid distribution section 200, a reactor 300, a treatment liquid distribution section 400, and a pressure pump for the liquid to be treated. Consists of PO1, additive liquid pressure pump PO2, safety valve SV, first air vent valve AV1, second air vent valve AV2, residual pressure vent valve PV, back pressure valve BV, heater (not shown), and control device (not shown) has been done. These components will be explained in detail below.

1. Processing liquid distribution section The processing liquid distribution section 100 is for guiding the processing liquid to the reactor 300, and is made of metal (for example, stainless steel), and is shown in FIGS. 1 to 4. As shown in FIG. These components will be explained in detail below.

(1) First distribution section The first distribution section 110 is for guiding the liquid to be treated to the second distribution section 120, and as shown in FIGS. , left side piping LP2, front side piping FP1 to FP5, right side piping RP1, rear side piping BP1, BP2, and connection piping CP1 to CP5. These components will be explained in detail below.

The liquid supply pipe LP1 is arranged on the left side of the organic matter decomposition apparatus 1, as shown in FIGS. 1 and 2. The inlet of the liquid supply pipe LP1 is used as a supply port for the liquid to be treated, and is connected to a liquid to be treated tank (not shown) in which the liquid to be treated containing harmful substances is stored. The outlet of the liquid supply pipe LP1 is flange-connected to the inlet of the left-hand pipe LP2, as shown in FIGS. 1 and 2.

The left side pipe LP2 is arranged on the left side of the organic matter decomposition device 1, as shown in FIGS. 1 and 2. As shown in FIGS. 1 and 2, the inlet of the left pipe LP2 is flange-connected to the outlet of the liquid supply pipe LP1, and the outlet of the left-hand pipe LP2 is flange-connected to the inlet of the front pipe FP1. Note that, as shown in FIGS. 1 and 2, a safety valve SV is attached to the left side pipe LP2.

The front pipes FP1 to FP5 are arranged in front of the rear pipes BP1 to BP5, as shown in FIGS. 1 to 4. The inlet of the front side piping FP1 is flange-connected to the outlet of the left side piping LP2 as shown in FIGS. 1 and 2, and the outlet of the front side piping FP1 is connected to the inlet of the connecting pipe CP1 as shown in FIGS. 1 and 3. Flange connected. The inlet of the front pipe FP2 is flange-connected to the outlet of the connecting pipe CP1, as shown in FIGS. 1 and 3, and the outlet of the front pipe FP2 is connected to the inlet of the connecting pipe CP2, as shown in FIGS. 1 and 2. Flange connected. The inlet of the front pipe FP3 is flange-connected to the outlet of the connecting pipe CP2, as shown in FIGS. 1 and 2, and the outlet of the front pipe FP3 is connected to the inlet of the connecting pipe CP3, as shown in FIGS. 1 and 3. Flange connected. The inlet of the front pipe FP4 is flange-connected to the outlet of the connecting pipe CP3, as shown in FIGS. 1 and 3, and the outlet of the front pipe FP4 is flange-connected to the inlet of the connecting pipe CP4, as shown in FIG. ing. The inlet of the front pipe FP5 is flange-connected to the outlet of the connecting pipe CP4, as shown in FIG. 2, and the outlet of the front pipe FP5 is flange-connected to the inlet of the right-hand pipe RP1, as shown in FIGS. 1 and 3. ing.

Note that, as shown in FIG. 1, the front pipe FP1 is inserted into openings formed on the left end surface and the right end surface of the front pipe 407 of the processing liquid distribution section 400, and is inserted into the inside of the front pipe 407 of the processing liquid distribution section 400. will be placed in As shown in FIG. 1, the front piping FP2 is inserted into openings formed on the left end surface and the right end surface of the front piping 406 of the processing liquid distribution section 400, and is arranged inside the front piping 406 of the processing liquid distribution section 400. be done. As shown in FIG. 1, the front piping FP3 is inserted into openings formed in the left end surface and the right end surface of the front piping 405 of the processing liquid distribution section 400, and is arranged inside the front piping 405 of the processing liquid distribution section 400. be done. As shown in FIG. 1, the front piping FP4 is inserted into openings formed on the left end surface and the right end surface of the front piping 404 of the processing liquid distribution section 400, and is arranged inside the front piping 404 of the processing liquid distribution section 400. be done. As shown in FIG. 1, the front piping FP5 is inserted into openings formed in the left end surface and the right end surface of the front piping 403 of the processing liquid distribution section 400, and is arranged inside the front piping 403 of the processing liquid distribution section 400. be done.

The right pipe RP1 is arranged on the right side of the organic matter decomposition device 1, as shown in FIGS. 1, 3, and 4. The inlet of the right side piping RP1 is flange-connected to the outlet of the front side piping FP5 as shown in FIGS. 1 and 3, and the outlet of the right side piping RP1 is connected to the inlet of the rear side piping BP1 as shown in FIGS. 3 and 4. is flange connected to. Note that, as shown in FIGS. 3 and 4, a first air vent valve AV1 is attached to the right side pipe RP1.

The rear pipes BP1 and BP2 are arranged on the rear side of the front pipes FP1 to FP5, as shown in FIGS. 1 to 4. The inlet of the rear piping BP1 is flange-connected to the outlet of the right piping RP1 as shown in FIGS. 3 and 4, and the outlet of the rear piping BP1 is connected to the connecting piping CP5 as shown in FIGS. 2 and 4. Flange connected to the inlet. The inlet of the rear piping BP2 is flange-connected to the outlet of the connecting pipe CP5 as shown in FIGS. 2 and 4, and the outlet of the rear piping BP2 is connected to the outlet of the connecting pipe CP6 as shown in FIGS. 3 and 4. Flange connected to the inlet.

As shown in FIGS. 1 and 3, the connecting pipe CP1 connects the front pipe FP1 and the front pipe FP2. As shown in FIGS. 1 and 2, the connecting pipe CP2 connects the front pipe FP2 and the front pipe FP3. As shown in FIGS. 1 and 3, the connecting pipe CP3 connects the front pipe FP3 and the front pipe FP4. As shown in FIG. 2, the connecting pipe CP4 connects the front pipe FP4 and the front pipe FP5. The connecting pipe CP5 connects the rear pipe BP1 and the rear pipe BP2, as shown in FIGS. 2 and 4.

(2) Second circulation section The second circulation section 120 is for guiding the liquid to be treated after hydrogen peroxide and nitric acid have been added to the reactor 300, as shown in FIGS. 2 to 4. It mainly consists of connecting pipes CP6 to CP9 and rear pipes BP3 to BP5. These components will be explained in detail below.

As shown in FIGS. 3 and 4, the connecting pipe CP6 connects the rear pipe BP2 and the rear pipe BP3. Note that, as shown in FIGS. 3 and 4, the end on the outlet side of the injection part 205 of the additive liquid distribution part 200 is inserted into the interior of the connection pipe CP6. The connecting pipe CP7 connects the rear pipe BP3 and the rear pipe BP4, as shown in FIGS. 2 and 4. As shown in FIGS. 3 and 4, the connecting pipe CP8 connects the rear pipe BP4 and the rear pipe BP5. Note that, as shown in FIGS. 3 and 4, the end on the outlet side of the injection part 206 of the additive liquid distribution part 200 is inserted into the interior of the connection pipe CP8. The connecting pipe CP9 connects the rear pipe BP5 and the first reaction pipe 301 of the reactor 300, as shown in FIGS. 2 and 4.

The inlet of the rear piping BP3 is flange-connected to the outlet of the connecting piping CP6, as shown in FIGS. 3 and 4, and the outlet of the rear piping BP3 is connected to the outlet of the connecting piping CP7, as shown in FIGS. 2 and 4. Flange connected to the inlet. The inlet of the rear piping BP4 is flange-connected to the outlet of the connecting pipe CP7 as shown in FIGS. 2 and 4, and the outlet of the rear piping BP4 is connected to the outlet of the connecting pipe CP8 as shown in FIGS. 3 and 4. Flange connected to the inlet. The inlet of the rear piping BP5 is flange-connected to the outlet of the connecting pipe CP8 as shown in FIGS. 3 and 4, and the outlet of the rear piping BP5 is connected to the outlet of the connecting pipe CP9 as shown in FIGS. 2 and 4. Flange connected to the inlet.

2. Additive liquid distribution section The additive liquid distribution section 200 is for supplying hydrogen peroxide and nitric acid to the liquid to be treated before the liquid to be treated reaches the catalyst. 100 to the second circulation section 120. Further, the additive liquid flow section 200 is made of metal (for example, stainless steel, etc.), and mainly includes a first pipe 201, a second pipe 202, and a third pipe, as shown in FIGS. 203, a fourth pipe 204, and injection parts 205 to 207. These components will be explained in detail below.

The inlet of the first pipe 201 is used as a supply port for hydrogen peroxide and nitric acid to be mixed with the liquid to be treated, and is connected to an additive liquid tank (not shown) in which hydrogen peroxide and nitric acid are stored. The outlet of the first pipe 201 is flange-connected to the inlet of the second pipe 202, as shown in FIG.

The inlet of the second pipe 202 is flange-connected to the inlet of the first pipe 201 as shown in FIG. 1, and the outlet of the second pipe 202 is connected to the inlet of the third pipe 203 as shown in FIGS. 1 and 2. is flange connected to. Note that, as shown in FIG. 1, a residual pressure relief valve PV is attached to the second pipe 202.

The inlet of the third pipe 203 is flange connected to the outlet of the second pipe 202 as shown in FIGS. 1 and 2, and the outlet of the third pipe 203 is connected to the fourth pipe as shown in FIGS. 1 and 3. A flange connection is made to the inlet of 204.

The inlet of the fourth pipe 204 is flange-connected to the outlet of the third pipe 203, as shown in FIGS. 1 and 3. As shown in FIGS. 1 and 3, the fourth piping 204 has three outlets: the upper end, the middle part located below the upper end, and the lower part below the middle part. It is formed. The outlet at the upper end of the fourth pipe 204 is connected to the inlet of the injection part 205, as shown in FIGS. 3 and 4. The outlet of the intermediate portion of the fourth pipe 204 is connected to the inlet of the injection part 206, as shown in FIGS. 3 and 4. The lower outlet of the fourth pipe 204 is connected to the inlet of the injection part 207, as shown in FIGS. 3 and 4.

The inlet of the injection part 205 is connected to the outlet at the upper end of the fourth pipe 204, as shown in FIGS. 3 and 4, and the end of the injection part 205 on the exit side is connected to the liquid distribution part as described above. It is inserted into the inside of the connection pipe CP6 of the second flow section 120 of No. 100. The inlet of the injection part 206 is connected to the outlet of the intermediate part of the fourth pipe 204 as shown in FIGS. 3 and 4, and the end of the injection part 206 on the exit side is connected to the liquid to be treated flow part as described above. It is inserted into the connecting pipe CP8 of the second flow section 120 of No. 100. Note that the hydrogen peroxide and nitric acid flowing through the injection section 205 are added to the liquid to be treated that has flowed into the connection pipe CP6 of the second distribution section 120 of the liquid distribution section 100, and the hydrogen peroxide and nitric acid flowing through the injection section 206 are is added to the liquid to be treated that has flowed into the connection pipe CP8 of the second circulation part 120 of the liquid to be treated part 100. The inlet of the injection part 207 is connected to the lower outlet of the fourth pipe 204 as shown in FIGS. 3 and 4, and the end of the injection part 207 on the outlet side is connected to the connecting pipe of the reactor 300 as described above. It is inserted into the inside of 303. Note that hydrogen peroxide and nitric acid flowing through the injection part 207 are added to the liquid to be treated flowing out from the first reaction pipe 301 of the reactor 300.

3. Reactor The reactor 300 is made of metal (for example, titanium (titanium alloy or pure titanium), etc.), and as shown in FIG. and a connecting pipe 303. These components will be explained in detail below.

A catalyst is fixed inside the first reaction pipe 301. The catalyst is, for example, a Fenton catalyst (e.g., an iron compound such as ferrous sulfate, a copper compound such as copper oxide, a mixture of copper and a metal element other than copper (e.g., nickel), etc.), and may be in the form of granules, pellets, etc. It has a shape such as a honeycomb structure or a honeycomb structure. Further, as shown in FIG. 4, the inlet of the first reaction pipe 301 is flange-connected to the outlet of the connection pipe CP9 of the second flow section 120 of the liquid flow section 100, and the outlet of the first reaction pipe 301 is As shown in FIG. 4, it is flange-connected to the inlet of the connecting pipe 303.

A catalyst is fixed inside the second reaction pipe 302. The catalyst is, for example, a Fenton catalyst (e.g., an iron compound such as ferrous sulfate, a copper compound such as copper oxide, a mixture of copper and a metal element other than copper (e.g., nickel), etc.), and may be in the form of granules, pellets, etc. It has a shape such as a honeycomb structure or a honeycomb structure. Further, the inlet of the second reaction pipe 302 is flange-connected to the outlet of the connecting pipe 303 as shown in FIG. A flange connection is made to the inlet of the left side pipe 401 of the section 400.

The connecting pipe 303 connects the first reaction pipe 301 and the second reaction pipe 302, as shown in FIGS. 3 and 4. Note that, as described above, the end on the outlet side of the injection part 207 of the additive liquid distribution part 200 is inserted into the inside of the connection pipe 303.

4. Processing liquid distribution section The processing liquid distribution section 400 is for guiding the liquid to be treated (hereinafter referred to as "processing liquid") after harmful substances have been decomposed to the outside, and is made of metal (for example, stainless steel). As shown in FIGS. 1, 2, and 4, it is mainly composed of a left side pipe 401, front side pipes 402 to 407, and a drain pipe 408. These components will be explained in detail below.

The left side pipe 401 is arranged on the left side of the organic matter decomposition apparatus 1, as shown in FIGS. 1, 2, and 4. The inlet of the left pipe 401 is flange-connected to the outlet of the second reaction pipe 302 of the reactor 300, as shown in FIGS. 1, 2, and 4, and the outlet of the left pipe 401 is It is flange-connected to the inlet of the front pipe 402 so that the front pipe 402 can be opened.

The front pipes 402 to 407 are arranged in front of the rear pipes BP1 to BP5 of the liquid distribution section 100, as shown in FIGS. 1 to 4. The front pipes 403 to 407 have a substantially cylindrical shape with a left end surface and a right end surface (see FIG. 1). Openings are formed in these left and right end surfaces. The front piping FP1 of the first distribution section 110 of the liquid distribution section 100 to be treated is inserted through this opening of the front piping 407 and arranged inside the front piping 407. The front piping FP2 of the first distribution section 110 of the liquid distribution section 100 to be treated is inserted through this opening of the front piping 406 and arranged inside the front piping 406. The front piping FP3 of the first distribution section 110 of the liquid distribution section 100 to be treated is inserted through this opening of the front piping 405 and arranged inside the front piping 405. The front piping FP4 of the first distribution section 110 of the liquid distribution section 100 to be treated is inserted through this opening of the front piping 404 and arranged inside the front piping 404. The front piping FP5 of the first distribution section 110 of the liquid distribution section 100 to be treated is inserted through this opening of the front piping 403 and arranged inside the front piping 403. Further, as shown in FIG. 1, in the front piping 403, 405, 407, the inlet forming part protrudes downward from the right end, and the outlet forming part protrudes upward from the left end. In this case, the inlet forming part projects downward from the left end, and the outlet forming part projects upward from the right end.

The inlet of the front piping 402 is flange-connected to the outlet of the left-hand piping 401 as shown in FIGS. 1 and 2, and the outlet of the front piping 402 is flange-connected to the inlet of the front piping 403 as shown in FIG. Connected. The inlet of the front pipe 403 is flange-connected to the outlet of the front pipe 402, as shown in FIG. 1, and the outlet of the front pipe 403 is flange-connected to the inlet of the front pipe 404, as shown in FIGS. 1 and 3. Ru. The inlet of the front pipe 404 is flange connected to the outlet of the front pipe 403 as shown in FIGS. 1 and 3, and the outlet of the front pipe 404 is connected to the inlet of the front pipe 405 as shown in FIGS. 1 and 2. Flange connected. The inlet of the front pipe 405 is flange connected to the outlet of the front pipe 404 as shown in FIGS. 1 and 2, and the outlet of the front pipe 405 is connected to the inlet of the front pipe 406 as shown in FIGS. 1 and 3. Flange connected. The inlet of the front pipe 406 is flanged to the outlet of the front pipe 405 as shown in FIGS. 1 and 3, and the outlet of the front pipe 406 is flanged to the inlet of the front pipe 407 as shown in FIG. Ru. As shown in FIG. 1, the inlet of the front pipe 407 is flanged to the outlet of the front pipe 406, and the outlet of the front pipe 407 is flanged to the inlet of the drain pipe 408.

The inlet of the drain pipe 408 is flange-connected to the outlet of the front pipe 407, as shown in FIG. 1, and the outlet of the drain pipe 408 is used as a discharge port for the processing liquid. Note that, as shown in FIGS. 1 to 4, a second air vent valve AV2 and a back pressure valve BV are attached to the drain pipe 408.

5. Pressure Pump for Processed Liquid The pressurization pump PO1 for processed liquid distributes the processed liquid in the processed liquid tank through the liquid supply pipe LP1 of the first distribution section 110 of the processed liquid distribution section 100. It plays the role of distributing information to the department 100. Note that the pressurizing pump PO1 for the liquid to be treated is connected to a control device.

6. Additive Liquid Pressure Pump The additive liquid pressure pump PO2 plays the role of distributing hydrogen peroxide and nitric acid in the additive liquid tank to the additive liquid distribution section 200 via the first pipe 201 of the additive liquid distribution section 200. ing. Note that the additive liquid pressurizing pump PO2 is connected to the control device.

7. Safety Valve The safety valve SV has the role of releasing the pressure inside (inside the system) of the treated liquid distribution section 100, the additive liquid distribution section 200, the reactor 300, and the processing liquid distribution section 400, and is shown in FIG. As such, it is attached to the left side piping LP2 of the first distribution section 110 of the liquid distribution section 100 to be treated.

8. First air vent valve The first air vent valve AV1 has the role of discharging air accumulated in the system to the outside, and as shown in FIGS. It is attached to the right side pipe RP1 of 110.

9. Second Air Vent Valve The second air vent valve AV2 has the role of discharging air accumulated in the system to the outside and releasing the pressure in the system, and as shown in FIGS. 1, 2, and 4. , is attached to the drain pipe 408 of the processing liquid distribution section 400.

10. Residual Pressure Release Valve The residual pressure release valve PV plays a role of releasing pressure within the system, and is attached to the second pipe 202 of the additive liquid distribution section 200, as shown in FIG.

11. Back Pressure Valve The back pressure valve BV plays the role of preventing the processing liquid from being discharged in an amount larger than a specified amount from the outlet of the drain pipe 408 of the processing liquid distribution section 400, and keeping the pressure in the system constant. , as shown in FIGS. 2 and 4, is attached to the drain pipe 408 of the processing liquid distribution section 400.

12. Heater The heater (not shown) is, for example, a ribbon heater or the like, and is attached to the outer surface of the rear piping BP1 to BP5 of the liquid distribution section 100 and the outer surface of the third piping 203 of the additive liquid distribution section 200. . Note that the heater is connected to a control device.

13. Control Device As described above, the control device (not shown) is connected to the liquid to be treated pressurizing pump PO1, the additive liquid pressurizing pump PO2, the heater, etc., and controls the on/off and output of these power supplies.

<Description of organic matter decomposition method using the organic matter decomposition device according to the embodiment of the present invention>
An organic matter decomposition method using the organic matter decomposition device 1 will be described below.

First, the pressurizing pump PO1 for the liquid to be treated causes the liquid to be treated containing harmful substances to flow into the liquid supply pipe LP1 of the first distribution part 110 of the liquid to be treated part 100. At this time, the pressure in the system is preferably set within the range of 1 MPa or more and 2.2 MPa or less, and preferably set within the range of 1.5 MPa or more and 2.0 MPa or less, by the back pressure valve BV. More preferred. The liquid to be treated is supplied to the first distribution section 110 of the liquid distribution section 100 through liquid supply piping LP1 → left side piping LP2 → front side piping FP1 → connection piping CP1 → front side piping FP2 → connection piping CP2 → front side piping FP3 → connection. Piping CP3 → Front piping FP4 → Connecting piping CP4 → Front piping FP5 → Right piping RP1 → Rear piping BP1 → Connecting piping CP5 → Rear piping BP2 → Connecting piping CP6 of the second distribution section 120 of the liquid distribution section 100 flow inside these in order. The liquid to be treated is heated by the heating section while flowing through the rear piping BP1, BP2 of the liquid to be treated distribution section 100.

Note that when the liquid to be treated flows into the connection pipe CP6 of the second distribution part 120 of the liquid to be treated part 100, the hydrogen peroxide and nitric acid flowing out from the injection part 205 of the additive liquid distribution part 200 flow into the liquid to be treated. added to. The liquid to be treated after the addition of hydrogen peroxide and nitric acid is transferred from the rear pipe BP3 of the second distribution section 120 of the liquid distribution section 100 to the connecting pipe CP7 to the rear piping BP4 to the connecting pipe CP8 to the rear. It flows inside these in the order of side pipe BP5→connection pipe CP9. The treated liquid to which hydrogen peroxide and nitric acid have been added is heated by the heating section while flowing through the rear piping BP3, BP4, BP5 of the treated liquid distribution section 100. Note that when the treated liquid to which hydrogen peroxide and nitric acid have been added flows into the connection pipe CP8 of the second distribution part 120 of the treated liquid distribution part 100, the liquid flows from the injection part 206 of the additive liquid distribution part 200. The hydrogen peroxide and nitric acid that flowed out are further added to the liquid to be treated. Hydrogen peroxide and nitric acid are flowed into the first pipe 201 of the additive liquid distribution section 200 by the additive liquid pressurizing pump PO2, and are transferred from the first piping 201 to the second piping 202 to the third piping 203 of the additive liquid distribution section 200. → Fourth pipe 204 → Injection parts 205, 206, and 207 in this order. Further, hydrogen peroxide and nitric acid are heated by the heating section while flowing through the third pipe 203 of the additive liquid distribution section 200. That is, heated hydrogen peroxide and nitric acid are added to the liquid to be treated.

After hydrogen peroxide and nitric acid have been added, the liquid to be treated is transferred from the connection pipe CP9 of the second circulation part 120 of the liquid distribution part 100 to the first reaction pipe 301 of the reactor 300→connection pipe 303→ It flows inside these in order of the second reaction pipe 302. When the liquid to be treated comes into contact with the catalyst in the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, harmful substances contained in the liquid to be treated are decomposed. Note that when the liquid to be treated is in contact with the catalyst in the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated is in the range of 0°C or more and 200°C or less. It is preferably within the range of 50°C or more and 200°C or less, more preferably within the range of 100°C or more and 200°C or less, and more preferably within the range of 150°C or more and 200°C or less. It is more preferable that the temperature is in the range of 180°C or more and 200°C or less.

Note that when the treated liquid to which hydrogen peroxide and nitric acid have been added is flowing through the connection pipe CP9 of the reactor 300, the hydrogen peroxide and nitric acid that flowed out from the injection part 207 of the additive liquid distribution part 200 also Further added to the liquid to be treated.

The processing liquid is then transferred from the second reaction pipe 302 of the reactor 300 to the left pipe 401 of the processing liquid distribution section 400 → front pipe 402 → front pipe 403 → front pipe 404 → front pipe 405 → front pipe 406 → front pipe 407. →Flows inside these in the order of drainage pipe 408. In addition, in more detail, the inside of the front pipe 403 is the inside of the front pipe 403 and the outside of the front pipe FP5 of the liquid distribution section 100, and the inside of the front pipe 404 is the inside of the front pipe 404 and the outside of the front pipe FP5 of the liquid distribution section 100. It is outside the front piping FP4 of the liquid distribution section 100, the inside of the front piping 405 is inside the front piping 405 and the outside of the front piping FP3 of the liquid distribution section 100, and the inside of the front piping 406 is inside the front piping FP4. 406 and the outside of the front pipe FP2 of the liquid to be processed portion 100, and the inside of the front pipe 407 is the inside of the front pipe 407 and the outside of the front pipe FP1 of the liquid to be processed portion 100. Finally, the processing liquid is discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400.

<Characteristics of the organic substance decomposition method according to the embodiment of the present invention>
(1)
In the organic substance decomposition method according to the embodiment of the present invention, hydrogen peroxide and nitric acid are added to a liquid to be treated containing organic substances, and the liquid to be treated is transferred to the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300. is brought into contact with the catalyst inside. Therefore, in this organic substance decomposition method, hydrogen peroxide is added to a liquid to be treated containing organic substances, and the liquid to be treated is brought into contact with the catalyst in the first reaction pipe 301 and second reaction pipe 302 of the reactor 300 to remove organic substances. The cost of decomposing organic matter can be kept as low as possible compared to when decomposing organic matter.

(2)
In the organic substance decomposition method according to the embodiment of the present invention, the liquid to be treated after hydrogen peroxide and nitric acid is added comes into contact with the catalyst in the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300. In this state, the temperature of the liquid to be treated is within the range of 0°C or more and 200°C or less. Therefore, in this organic substance decomposition method, the decomposition of organic substances can be further promoted without deactivating the catalyst.

<Modified example>
(A)
In the organic matter decomposition apparatus 1 according to the previous embodiment, the heating section is connected to the outer surface of the rear piping BP1, BP2, BP3, BP4, BP5 of the liquid distribution section 100 and the third piping 203 of the additive liquid distribution section 200. It was attached to the outside. However, when the treated liquid to which hydrogen peroxide and nitric acid have been added comes into contact with the catalyst in the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the treated liquid reaches 100°C. As long as the temperature is within the range of 200°C or less, the heating part may be attached to the outer surface of at least one of these pipes, or the rear pipes BP1, BP2, BP3, It may be attached to at least one outer surface other than BP4, BP5, it may be attached to at least one outer surface other than the third pipe 203 of the additive liquid distribution section 200, or it may be attached to the outer surface of the reactor 300. It's okay.

(B)
Although not mentioned in the organic matter decomposition device 1 according to the previous embodiment, the number of pipes that constitute the treated liquid distribution section 100, the additive liquid distribution section 200, the reactor 300, and the treatment liquid distribution section 400 is not limited.

(C)
In the organic matter decomposition apparatus 1 according to the previous embodiment, it was said that the pressure in the system is preferably set within the range of 1 MPa or more and 2.2 MPa or less by the back pressure valve BV. However, pressure may not be applied to the system by the back pressure valve BV.

(D)
In the organic substance decomposition apparatus 1 according to the previous embodiment, the liquid to be treated after hydrogen peroxide and nitric acid is added comes into contact with the catalyst in the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300. In this state, the temperature of the liquid to be treated is preferably within the range of 0°C or more and 200°C or less. However, if the catalyst is not deactivated or the organic matter is sufficiently decomposed, the temperature of the liquid to be treated should be higher than 200°C under the same conditions (for example, within the range of 200°C to 400°C, 200°C (e.g., within a range of more than 300°C or less).

(E)
Although not mentioned in the organic substance decomposition apparatus 1 according to the previous embodiment, a catalyst may also be fixed inside the connecting pipe 303 of the reactor 300.

(F)
In the previous embodiment, decomposition of organic matter by the organic matter decomposition method according to the present invention was realized by using the organic matter decomposition device 1. However, decomposition of organic matter by the organic matter decomposition method according to the present invention may be realized without using the organic matter decomposition device 1. For example, hydrogen peroxide and nitric acid may be added to a liquid to be treated containing organic matter, and the liquid to be treated and the catalyst may be put into a container all at once. The liquid to be treated, to which hydrogen peroxide and nitric acid have been added, may be heated by a heating unit attached to the outer surface of the container. Alternatively, at least one of the liquid to be treated containing organic matter, hydrogen peroxide, and nitric acid may be heated in advance before hydrogen peroxide and nitric acid are added to the liquid to be treated containing organic matter.

(G)
In the organic matter decomposition apparatus 1 according to the previous embodiment, hydrogen peroxide and nitric acid flowed through the additive liquid distribution section 200 and were added to the liquid to be treated. However, the additive liquid flow section 200 may not be provided, and a hydrogen peroxide flow section through which only hydrogen peroxide flows and a nitric acid flow section through which only nitric acid flows may be provided. Then, the hydrogen peroxide flowing out from the outlet of the hydrogen peroxide flow section is transferred to the inside of the connection pipes CP6 and CP8 of the second flow section 120 of the liquid flow section 100 and the inside of the connection pipe CP9 of the reactor 300. The nitric acid added to the liquid and flowing out from the outlet of the nitric acid flow section causes the liquid to be treated to flow inside the connecting pipes CP6 and CP8 of the second flow section 120 of the liquid flowing section 100 and inside the connecting pipe CP9 of the reactor 300. may be added to.

(H)
In the organic matter decomposition apparatus 1 according to the previous embodiment, the first air vent valve AV1 is attached to the right pipe RP1 of the first distribution section 110 of the liquid distribution section 100, and the second air vent valve AV2 is attached to the right side pipe RP1 of the first distribution section 110 of the liquid distribution section 100. It was attached to the drain pipe 408 of the section 400. However, the piping to which the air vent valve is attached is not limited to these pipings. That is, an air vent valve may be attached to at least one of the pipes forming the treated liquid distribution section 100, the additive liquid distribution section 200, and the processing liquid distribution section 400.

(I)
Although not mentioned in the organic matter decomposition device 1 according to the previous embodiment, at least one of the pipes constituting the treated liquid distribution section 100, the additive liquid distribution section 200, and the treatment liquid distribution section 400 may be made of titanium. good. For example, all of the piping of the liquid distribution section 100, the additive liquid distribution section 200, and the treatment liquid distribution section 400 may be made of titanium, or the connection piping CP8 and the rear piping BP5 of the liquid distribution section 100 may be made of titanium. The connecting pipe CP9 may be made of titanium, and the first pipe 201, the second pipe 202, the third pipe 203, and the fourth pipe 204 of the additive liquid distribution section 200 may be made of titanium.

Note that the above modifications may be applied alone or in combination.

<Examples and comparative examples>
EXAMPLES Below, Examples and Comparative Examples will be shown to explain the present invention in more detail, but the present invention is not limited to these Examples.

Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. Then, as shown in Table 1, the liquid to be treated having a total organic carbon concentration (TOC) of 1007.4 mg/L and a concentration of 1,4-dioxane of 1600 mg/L is supplied to the liquid supply pipe of the liquid to be treated flow section 100. Nitric acid and hydrogen peroxide were made to flow into the first pipe 201 of the additive liquid flow section 200 so that the concentrations were 25 mM of nitric acid and 100 mM of hydrogen peroxide. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide and nitric acid are added varies within a range of 180°C or more and 200°C or less. I confirmed that In addition, in a state where the liquid to be treated after hydrogen peroxide and nitric acid has been added is flowing into the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, there are almost no bubbles in the reactor 300. We have confirmed that this has not occurred. When the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 402.5 mg/L, and the 1,4-dioxane concentration was 402.5 mg/L. was 70 mg/L. The results show that the TOC removal rate was 60% and the 1,4-dioxane decomposition rate was 95.6% (see Table 1).

Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. Then, as shown in Table 1, the liquid to be treated having a total organic carbon concentration (TOC) of 1007 mg/L and a concentration of 1,4-dioxane of 1600 mg/L is introduced into the liquid supply pipe LP1 of the liquid distribution part 100. Nitric acid and hydrogen peroxide were flowed into the first pipe 201 of the additive liquid flow section 200 so that the concentrations were 25 mM of nitric acid and 150 mM of hydrogen peroxide. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide and nitric acid are added varies within a range of 180°C or more and 200°C or less. I confirmed that In addition, in a state where the liquid to be treated after hydrogen peroxide and nitric acid has been added is flowing into the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, there are almost no bubbles in the reactor 300. We have confirmed that this has not occurred. When the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 154.9 mg/L, and the 1,4-dioxane concentration was 154.9 mg/L. was 6 mg/L. The results show that the TOC removal rate was 84.6% and the 1,4-dioxane decomposition rate was 99.6% (see Table 1).

Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. Then, as shown in Table 1, the liquid to be treated having a total organic carbon concentration (TOC) of 1022.2 mg/L and a concentration of 1,4-dioxane of 1700 mg/L is supplied to the liquid supply pipe of the liquid distribution part 100. Nitric acid and hydrogen peroxide were flowed into the first pipe 201 of the additive liquid flow section 200 so that the concentrations were 40 mM of nitric acid and 150 mM of hydrogen peroxide. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide and nitric acid are added varies within a range of 180°C or more and 200°C or less. I confirmed that In addition, in a state where the liquid to be treated after hydrogen peroxide and nitric acid has been added is flowing into the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, there are almost no bubbles in the reactor 300. We have confirmed that this has not occurred. When the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 176.4 mg/L, and the 1,4-dioxane concentration was 176.4 mg/L. was 16 mg/L. The results show that the TOC removal rate was 82.7% and the 1,4-dioxane decomposition rate was 99.1% (see Table 1).

Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. Then, as shown in Table 1, the liquid to be treated having a total organic carbon concentration (TOC) of 1029.6 mg/L and a concentration of 1,4-dioxane of 1800 mg/L is supplied to the liquid supply pipe of the liquid distribution part 100. Nitric acid and hydrogen peroxide were flowed into the first pipe 201 of the additive liquid flow section 200 so that the concentrations were 14 mM of nitric acid and 200 mM of hydrogen peroxide. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide and nitric acid are added varies within a range of 180°C or more and 200°C or less. I confirmed that In addition, in a state where the liquid to be treated after hydrogen peroxide and nitric acid has been added is flowing into the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, there are almost no bubbles in the reactor 300. We have confirmed that this has not occurred. When the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 401 mg/L, and the 1,4-dioxane concentration was 78 mg. /L. The results show that the TOC removal rate was 61.1% and the 1,4-dioxane decomposition rate was 95.7% (see Table 1).

Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. As shown in Table 1, a liquid to be treated having a total organic carbon concentration (TOC) of 1020.6 mg/L and a 1,4-dioxane concentration of 1600 mg/L is supplied to the liquid supply pipe of the liquid to be treated flow section 100. Nitric acid and hydrogen peroxide were allowed to flow into the first pipe 201 of the additive liquid flow section 200 so that the resulting amounts were 25 mM of nitric acid and 200 mM of hydrogen peroxide. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide and nitric acid are added varies within a range of 180°C or more and 200°C or less. I confirmed that In addition, in a state where the liquid to be treated after hydrogen peroxide and nitric acid has been added is flowing into the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, there are almost no bubbles in the reactor 300. We have confirmed that this has not occurred. When the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 14.8 mg/L, and the 1,4-dioxane concentration was 14.8 mg/L. was 0.06 mg/L. The results show that the TOC removal rate is 98.5% and the 1,4-dioxane decomposition rate is approximately 100% (≈99.99...%) (see Table 1).

(Comparative example 1)
Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. Then, as shown in Table 1, the liquid to be treated having a total organic carbon concentration (TOC) of 1034.6 mg/L is flowed into the liquid supply pipe LP1 of the liquid to be treated flow section 100, and 100 mM of hydrogen peroxide is added to the liquid to be treated. Hydrogen peroxide was allowed to flow into the first pipe 201 of the additive liquid flow section 200 so that In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide is added changes within a range of 180°C or more and 200°C or less. It was confirmed. Then, when the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 549.3 mg/L. As a result, it was found that the TOC removal rate was 46.9% (see Table 1).

(Comparative example 2)
Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. As shown in Table 1, the liquid to be treated having a total organic carbon concentration (TOC) of 1021.8 mg/L and a concentration of 1,4-dioxane of 1900 mg/L is supplied to the liquid supply pipe of the liquid to be treated flow section 100. Hydrogen peroxide was caused to flow into the first pipe 201 of the additive liquid flow section 200 so that the hydrogen peroxide concentration was 300 mM. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide is added changes within a range of 180°C or more and 200°C or less. It was confirmed. Further, in a state where the liquid to be treated after hydrogen peroxide has been added is flowing into the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, many bubbles are generated in the reactor 300. I confirmed that When the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 122.5 mg/L, and the 1,4-dioxane concentration was 122.5 mg/L. was 160 mg/L. The results show that the TOC removal rate was 88% and the 1,4-dioxane decomposition rate was 91.6% (see Table 1).

(Comparative example 3)
Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. Then, as shown in Table 1, the liquid to be treated having a total organic carbon concentration (TOC) of 1024.2 mg/L was flowed into the liquid supply pipe LP1 of the liquid to be treated distribution section 100, and 10 mM of sulfuric acid and peroxide were added. Sulfuric acid and hydrogen peroxide were flowed into the first pipe 201 of the additive liquid flow section 200 so that the hydrogen concentration was 100 mM. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide and sulfuric acid are added varies within a range of 180°C or more and 200°C or less. I confirmed that Then, when the processing liquid discharged from the outlet of the drain pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 755.1 mg/L. As a result, it was found that the TOC removal rate was 26.3% (see Table 1).

(Comparative example 4)
Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. Then, as shown in Table 1, the liquid to be treated whose total organic carbon concentration (TOC) is 1025.6 mg/L is flowed into the liquid supply pipe LP1 of the liquid to be treated flow section 100, so that the concentration of nitric acid is 120 mM. Then, nitric acid was allowed to flow into the first pipe 201 of the additive liquid flow section 200. Then, it is confirmed that the temperature of the liquid to be treated after nitric acid is added changes within the range of 180°C or more and 200°C or less in the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300. confirmed. Then, when the processing liquid discharged from the outlet of the drain pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 972.8 mg/L. As a result, it was found that the TOC removal rate was 5.1% (see Table 1).

(Comparative example 5)
Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. As shown in Table 2, a liquid to be treated having a total organic carbon concentration (TOC) of 34,000 mg/L, a phenol concentration of 29,000 mg/L, and a formaldehyde concentration of 2,300 mg/L is supplied to the liquid to be treated flow section 100. Hydrogen peroxide was caused to flow into the first pipe 201 of the additive liquid flow section 200 so that the hydrogen peroxide concentration was 300 mM. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide is added changes within a range of 180°C or more and 200°C or less. It was confirmed. When the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 2, the total organic carbon concentration was 17,350 mg/L, the phenol concentration was 9,600 mg/L, Formaldehyde concentration was 970 mg/L. The results show that the TOC removal rate was 49%, the phenol decomposition rate was 66.9%, and the formaldehyde decomposition rate was 57.8% (see Table 2).

(Comparative example 6)
Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. Then, as shown in Table 3, a liquid to be treated having a toluene concentration of 1 mg/L, an ethanol concentration of 40 mg/L, and a N,N-dimethylformamide concentration of 100 mg/L is supplied to the liquid to be treated flowing section 100. Hydrogen peroxide was caused to flow into the first pipe 201 of the additive liquid distribution section 200 so that the hydrogen peroxide concentration was 300 mM. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide is added changes within a range of 180°C or more and 200°C or less. It was confirmed. When the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 3, the toluene concentration was 0.12 mg/L, the ethanol concentration was 330 mg/L, and the N ,N-dimethylformamide concentration was 40 mg/L or less. The results show that the toluene decomposition rate is 88% and the N,N-dimethylformamide decomposition rate is 60%. It is assumed that the amount of ethanol is increased due to reaction by-products (see Table 3).

[Comparative verification of Examples and Comparative Examples]
Example 2 and Comparative Example 2 will be compared and verified regarding the cost of decomposing organic matter. In addition, in these examples, nitric acid (62.5%) which is 900 yen/500 mL (1.8 yen/mL), hydrogen peroxide (32.8%) which is 1850 yen/500 mL (3.7 yen/mL) %) is used. As in Example 2, when 25mM (0.025mol/L) nitric acid and 150mM (0.15mol/L) hydrogen peroxide are caused to flow into the first pipe 201 of the additive liquid flow section 200, the following From the calculation formula, 54.7 yen is required for 1 L of the liquid to be treated.
Nitric acid: 1.8 yen/mL x 63 g/mol x 0.025 mol/L x 100 ÷ 62.5% ÷ specific gravity 1.38 ≒ 3.3 yen/L
Hydrogen peroxide: 3.7 yen/mL x 34 g/mol x 0.15 mol/L x 100 ÷ 32.8% ÷ specific gravity 1.12 ≒ 51.4 yen/L
Total: 3.3 yen/L + 51.4 yen/L = 54.7 yen/L

As in Comparative Example 2, when 300mM (0.3mol/L) of hydrogen peroxide is flowed into the first pipe 201 of the additive liquid distribution section 200, the calculation formula below shows that 300mM (0.3mol/L) of hydrogen peroxide is Therefore, 102.8 yen is required.
Hydrogen peroxide: 3.7 yen/mL x 34 g/mol x 0.3 mol/L x 100 ÷ 32.8% ÷ specific gravity 1.12 ≒ 102.8 yen/L

From the above, by adding hydrogen peroxide and nitric acid to the liquid to be treated containing organic matter and bringing the liquid to be treated into contact with the catalyst, half the amount of hydrogen peroxide that would be required when nitric acid is not added to the liquid to be treated can be reduced. It has been revealed that hydrogen peroxide has the same or better ability to decompose organic matter than when nitric acid is not added, and that the cost of decomposing organic matter can be reduced by about half.

Next, Examples 1 to 5 and Comparative Example 2 will be compared and verified to see if bubbles are generated in the reactor 300. In Examples 1 to 5, as described above, in a state where the liquid to be treated after adding hydrogen peroxide and nitric acid is flowing into the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300. It has been confirmed that almost no bubbles are generated within the reactor 300. On the other hand, in Comparative Example 2, in a state where the liquid to be treated after adding hydrogen peroxide is flowing into the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, It has been confirmed that many bubbles are generated. When a large number of bubbles are generated in the reactor 300, there is a possibility that the liquid to be treated cannot flow into the reactor 300 or that the treated liquid cannot flow out from the reactor 300. Therefore, the organic matter decomposition method according to the present invention can reduce the occurrence of such a fear as much as possible.

1 Organic matter decomposition device 100 To-be-treated liquid distribution section (first supply section)
200 Additive liquid distribution section (second supply section)
300 reactor

The present invention relates to an organic matter decomposition method and an organic matter decomposition device.

In the past, ``organohalogen compound characterized by heating an organic halogen compound from 100°C to 200°C in the presence of a catalyst consisting of copper oxide and hydrogen peroxide to perform a hydrothermal oxidation reaction using the Fenton method. A method for decomposing a compound has been proposed (see, for example, Publication No. 2014/080739).

Re-table 2014/080739 publication

By the way, when using the decomposition treatment method described above to sufficiently decompose organic substances in the liquid to be treated (for example, organic substances such as 1,4-dioxane, which is subject to the PRTR system), a large amount of It was necessary to add hydrogen peroxide and then bring the treated liquid into contact with the catalyst. For this reason, the above-described decomposition treatment method has a problem in that the cost for decomposing organic matter increases.

An object of the present invention is to reduce the cost of decomposing organic matter as much as possible compared to the case where hydrogen peroxide is added to a liquid to be treated containing organic matter and the liquid to be treated is brought into contact with a catalyst to decompose the organic matter. An object of the present invention is to provide a decomposition treatment method and an organic substance decomposition device.

The organic substance decomposition method according to the first aspect of the present invention includes adding hydrogen peroxide and nitric acid to a liquid to be treated containing at least 1,4-dioxane as an organic substance, and bringing the liquid to be treated into contact with a copper-nickel catalyst as a Fenton catalyst. . Further, the temperature of the liquid to be treated after adding hydrogen peroxide and nitric acid is within the range of 180°C or more and 200°C or less.

As a result of intensive studies by the inventors of the present application, by adding not only hydrogen peroxide but also nitric acid to the liquid to be treated containing organic matter, a smaller amount of hydrogen peroxide can be used than would be required if nitric acid was not added. It was revealed that the organic matter decomposition ability was equivalent to or higher than that without adding nitric acid. The price of hydrogen peroxide and nitric acid when nitric acid is added is lower than the price of hydrogen peroxide when nitric acid is not added. Therefore, in this method of decomposing organic matter, the cost for decomposing organic matter can be kept as low as possible compared to the case where hydrogen peroxide is added to the liquid to be treated containing organic matter and the liquid to be treated is brought into contact with a catalyst to decompose the organic matter. I can do it. In addition, as a result of intensive studies by the inventors of the present application, it has been found that by keeping the temperature of the liquid to be treated after adding hydrogen peroxide and nitric acid within the range of 180°C to 200°C, organic substances can be removed without deactivating the catalyst. It has become clear that the decomposition of can be further promoted.

The organic matter decomposition method according to the second aspect of the present invention is the organic matter decomposition method according to the first aspect, wherein the molar concentration of hydrogen peroxide is in a range of 150/40 times or more and 200/14 times or less of the molar concentration of nitric acid. It is within.

The organic matter decomposition device according to the third aspect of the present invention includes a first supply section, a second supply section, and a heating section . The first supply unit supplies a liquid to be treated containing at least 1,4-dioxane as an organic substance to a copper-nickel catalyst serving as a Fenton catalyst . The second supply unit supplies hydrogen peroxide and nitric acid to the liquid to be treated before the liquid to be treated reaches the copper-nickel catalyst. The heating section is for adjusting the temperature of the liquid to be treated after adding hydrogen peroxide and nitric acid to within a range of 180°C or more and 200°C or less.

As a result of intensive studies by the inventors of the present application, by adding not only hydrogen peroxide but also nitric acid to the liquid to be treated containing organic matter, a smaller amount of hydrogen peroxide can be used than would be required if nitric acid was not added. It was revealed that the organic matter decomposition ability was equivalent to or higher than that without adding nitric acid. The price of hydrogen peroxide and nitric acid when nitric acid is added is lower than the price of hydrogen peroxide when nitric acid is not added. Therefore, in this organic matter decomposition device, the cost for decomposing organic matter can be kept as low as possible compared to the case where hydrogen peroxide is added to the liquid to be treated containing organic matter and the liquid to be treated is brought into contact with a catalyst to decompose the organic matter. I can do it. Moreover, according to the above configuration, the decomposition of organic matter can be further promoted without deactivating the catalyst.

The organic matter decomposition device according to the fourth aspect of the present invention is the organic matter decomposition device according to the third aspect, and further includes a reactor. In the reactor, a copper-nickel catalyst is fixed. Moreover, the outlet of the first supply section is connected to the inlet of the reactor. The second supply section has an outlet connected to the first supply section.

According to the above configuration, the catalyst is fixed in the reactor. Therefore, in this organic matter decomposition device, it is possible to continuously perform the decomposition treatment of organic matter contained in the liquid to be treated.

The organic matter decomposition device according to the fifth aspect of the present invention is the organic matter decomposition device according to the third or fourth aspect, wherein the molar concentration of hydrogen peroxide is 150/40 times or more the molar concentration of nitric acid or more, and 200/14. It is within the range of twice or less .

FIG. 1 is a front view of an organic matter decomposition device according to an embodiment of the present invention. FIG. 1 is a left side view of an organic matter decomposition device according to an embodiment of the present invention. FIG. 1 is a right side view of an organic matter decomposition device according to an embodiment of the present invention. FIG. 1 is a rear view of an organic matter decomposition device according to an embodiment of the present invention.

<Description of organic substance decomposition method according to embodiment of the present invention>
In the organic substance decomposition method according to the embodiment of the present invention, hydrogen peroxide and nitric acid are added to a liquid to be treated containing organic substances, and the liquid to be treated is brought into contact with a catalyst. For example, a catalyst is put into a container containing a liquid to be treated after adding hydrogen peroxide and nitric acid, or a liquid to be treated after adding hydrogen peroxide and nitric acid is allowed to flow into a container containing a catalyst. By doing so, the liquid to be treated after adding hydrogen peroxide and nitric acid can be brought into contact with the catalyst. Organic matter is decomposed by the liquid to be treated after adding hydrogen peroxide and nitric acid coming into contact with a catalyst. Examples of organic substances include 1,4-dioxane, 1,3-dioxolane, 1,2-dichloroethane, 1,1-dichloroethylene, dichloromethane, chloroform, 1,1,1-trichloroethane, and 1,1-dichloroethane, which are subject to the PRTR system. , 2-trichloroethane, carbon tetrachloride, 1,2-dichloropropane, 1,3-dichloropropene, bromodichloromethane, trichloroethylene, tetrachloroethylene, trichlorobenzene, dichlorobenzene, dioxins, 1,2-epoxybutane, chlorodifluoromethane, These include 1-chloro-1,1-difluoroethane, perfluoro, phenol, N,N-dimethylformamide, formaldehyde, and toluene. The catalyst is, for example, a Fenton catalyst (eg, an iron compound such as ferrous sulfate, a copper compound such as copper oxide, a mixture of copper and a metal element other than copper (eg, nickel, etc.)). In addition, in the organic matter decomposition method according to the embodiment of the present invention, the temperature of the liquid to be treated after adding hydrogen peroxide and nitric acid is preferably within the range of 0°C or more and 200°C or less, and preferably 50°C or more. It is more preferably within the range of 200°C or less, more preferably within the range of 100°C or more and 200°C or less, even more preferably within the range of 150°C or more and 200°C or less, and 180°C or more and 200°C It is particularly preferable that it is within the following range.

When decomposing organic matter contained in a liquid to be treated using the organic matter decomposition method according to the embodiment of the present invention, it is preferable to use an organic matter decomposition apparatus 1 shown in FIGS. 1 to 4. The organic matter decomposition device 1 will be explained below.

<Configuration of an organic matter decomposition device according to an embodiment of the present invention>
As shown in FIGS. 1 to 4, the organic matter decomposition device 1 mainly includes a liquid to be treated distribution section 100, an additive liquid distribution section 200, a reactor 300, a treatment liquid distribution section 400, and a pressure pump for the liquid to be treated. Consists of PO1, additive liquid pressure pump PO2, safety valve SV, first air vent valve AV1, second air vent valve AV2, residual pressure vent valve PV, back pressure valve BV, heater (not shown), and control device (not shown) has been done. These components will be explained in detail below.

1. Processing liquid distribution section The processing liquid distribution section 100 is for guiding the processing liquid to the reactor 300, and is made of metal (for example, stainless steel), and is shown in FIGS. 1 to 4. As shown in FIG. These components will be explained in detail below.

(1) First distribution section The first distribution section 110 is for guiding the liquid to be treated to the second distribution section 120, and as shown in FIGS. , left side piping LP2, front side piping FP1 to FP5, right side piping RP1, rear side piping BP1, BP2, and connection piping CP1 to CP5. These components will be explained in detail below.

The liquid supply pipe LP1 is arranged on the left side of the organic matter decomposition apparatus 1, as shown in FIGS. 1 and 2. The inlet of the liquid supply pipe LP1 is used as a supply port for the liquid to be treated, and is connected to a liquid to be treated tank (not shown) in which the liquid to be treated containing harmful substances is stored. The outlet of the liquid supply pipe LP1 is flange-connected to the inlet of the left-hand pipe LP2, as shown in FIGS. 1 and 2.

The left side pipe LP2 is arranged on the left side of the organic matter decomposition device 1, as shown in FIGS. 1 and 2. As shown in FIGS. 1 and 2, the inlet of the left pipe LP2 is flange-connected to the outlet of the liquid supply pipe LP1, and the outlet of the left-hand pipe LP2 is flange-connected to the inlet of the front pipe FP1. Note that, as shown in FIGS. 1 and 2, a safety valve SV is attached to the left side pipe LP2.

The front pipes FP1 to FP5 are arranged in front of the rear pipes BP1 to BP5, as shown in FIGS. 1 to 4. The inlet of the front side piping FP1 is flange-connected to the outlet of the left side piping LP2 as shown in FIGS. 1 and 2, and the outlet of the front side piping FP1 is connected to the inlet of the connecting pipe CP1 as shown in FIGS. 1 and 3. Flange connected. The inlet of the front pipe FP2 is flange-connected to the outlet of the connecting pipe CP1, as shown in FIGS. 1 and 3, and the outlet of the front pipe FP2 is connected to the inlet of the connecting pipe CP2, as shown in FIGS. 1 and 2. Flange connected. The inlet of the front pipe FP3 is flange-connected to the outlet of the connecting pipe CP2, as shown in FIGS. 1 and 2, and the outlet of the front pipe FP3 is connected to the inlet of the connecting pipe CP3, as shown in FIGS. 1 and 3. Flange connected. The inlet of the front pipe FP4 is flange-connected to the outlet of the connecting pipe CP3, as shown in FIGS. 1 and 3, and the outlet of the front pipe FP4 is flange-connected to the inlet of the connecting pipe CP4, as shown in FIG. ing. The inlet of the front pipe FP5 is flange-connected to the outlet of the connecting pipe CP4, as shown in FIG. 2, and the outlet of the front pipe FP5 is flange-connected to the inlet of the right-hand pipe RP1, as shown in FIGS. 1 and 3. ing.

Note that, as shown in FIG. 1, the front pipe FP1 is inserted into openings formed on the left end surface and the right end surface of the front pipe 407 of the processing liquid distribution section 400, and is inserted into the inside of the front pipe 407 of the processing liquid distribution section 400. will be placed in As shown in FIG. 1, the front piping FP2 is inserted into openings formed on the left end surface and the right end surface of the front piping 406 of the processing liquid distribution section 400, and is arranged inside the front piping 406 of the processing liquid distribution section 400. be done. As shown in FIG. 1, the front piping FP3 is inserted into openings formed in the left end surface and the right end surface of the front piping 405 of the processing liquid distribution section 400, and is arranged inside the front piping 405 of the processing liquid distribution section 400. be done. As shown in FIG. 1, the front piping FP4 is inserted into openings formed on the left end surface and the right end surface of the front piping 404 of the processing liquid distribution section 400, and is arranged inside the front piping 404 of the processing liquid distribution section 400. be done. As shown in FIG. 1, the front piping FP5 is inserted into openings formed in the left end surface and the right end surface of the front piping 403 of the processing liquid distribution section 400, and is arranged inside the front piping 403 of the processing liquid distribution section 400. be done.

The right pipe RP1 is arranged on the right side of the organic matter decomposition device 1, as shown in FIGS. 1, 3, and 4. The inlet of the right side piping RP1 is flange-connected to the outlet of the front side piping FP5 as shown in FIGS. 1 and 3, and the outlet of the right side piping RP1 is connected to the inlet of the rear side piping BP1 as shown in FIGS. 3 and 4. is flange connected to. Note that, as shown in FIGS. 3 and 4, a first air vent valve AV1 is attached to the right side pipe RP1.

The rear pipes BP1 and BP2 are arranged on the rear side of the front pipes FP1 to FP5, as shown in FIGS. 1 to 4. The inlet of the rear piping BP1 is flange-connected to the outlet of the right piping RP1 as shown in FIGS. 3 and 4, and the outlet of the rear piping BP1 is connected to the connecting piping CP5 as shown in FIGS. 2 and 4. Flange connected to the inlet. The inlet of the rear piping BP2 is flange-connected to the outlet of the connecting pipe CP5 as shown in FIGS. 2 and 4, and the outlet of the rear piping BP2 is connected to the outlet of the connecting pipe CP6 as shown in FIGS. 3 and 4. Flange connected to the inlet.

As shown in FIGS. 1 and 3, the connecting pipe CP1 connects the front pipe FP1 and the front pipe FP2. As shown in FIGS. 1 and 2, the connecting pipe CP2 connects the front pipe FP2 and the front pipe FP3. As shown in FIGS. 1 and 3, the connecting pipe CP3 connects the front pipe FP3 and the front pipe FP4. As shown in FIG. 2, the connecting pipe CP4 connects the front pipe FP4 and the front pipe FP5. The connecting pipe CP5 connects the rear pipe BP1 and the rear pipe BP2, as shown in FIGS. 2 and 4.

(2) Second circulation section The second circulation section 120 is for guiding the liquid to be treated after hydrogen peroxide and nitric acid have been added to the reactor 300, as shown in FIGS. 2 to 4. It mainly consists of connecting pipes CP6 to CP9 and rear pipes BP3 to BP5. These components will be explained in detail below.

As shown in FIGS. 3 and 4, the connecting pipe CP6 connects the rear pipe BP2 and the rear pipe BP3. Note that, as shown in FIGS. 3 and 4, the end on the outlet side of the injection part 205 of the additive liquid distribution part 200 is inserted into the interior of the connection pipe CP6. The connecting pipe CP7 connects the rear pipe BP3 and the rear pipe BP4, as shown in FIGS. 2 and 4. As shown in FIGS. 3 and 4, the connecting pipe CP8 connects the rear pipe BP4 and the rear pipe BP5. Note that, as shown in FIGS. 3 and 4, the end on the outlet side of the injection part 206 of the additive liquid distribution part 200 is inserted into the interior of the connection pipe CP8. The connecting pipe CP9 connects the rear pipe BP5 and the first reaction pipe 301 of the reactor 300, as shown in FIGS. 2 and 4.

The inlet of the rear piping BP3 is flange-connected to the outlet of the connecting piping CP6, as shown in FIGS. 3 and 4, and the outlet of the rear piping BP3 is connected to the outlet of the connecting piping CP7, as shown in FIGS. 2 and 4. Flange connected to the inlet. The inlet of the rear piping BP4 is flange-connected to the outlet of the connecting pipe CP7 as shown in FIGS. 2 and 4, and the outlet of the rear piping BP4 is connected to the outlet of the connecting pipe CP8 as shown in FIGS. 3 and 4. Flange connected to the inlet. The inlet of the rear piping BP5 is flange-connected to the outlet of the connecting pipe CP8 as shown in FIGS. 3 and 4, and the outlet of the rear piping BP5 is connected to the outlet of the connecting pipe CP9 as shown in FIGS. 2 and 4. Flange connected to the inlet.

2. Additive liquid distribution section The additive liquid distribution section 200 is for supplying hydrogen peroxide and nitric acid to the liquid to be treated before the liquid to be treated reaches the catalyst. 100 to the second circulation section 120. Further, the additive liquid flow section 200 is made of metal (for example, stainless steel, etc.), and as shown in FIGS. 203, a fourth pipe 204, and injection parts 205 to 207. These components will be explained in detail below.

The inlet of the first pipe 201 is used as a supply port for hydrogen peroxide and nitric acid to be mixed with the liquid to be treated, and is connected to an additive liquid tank (not shown) in which hydrogen peroxide and nitric acid are stored. The outlet of the first pipe 201 is flange-connected to the inlet of the second pipe 202, as shown in FIG.

The inlet of the second pipe 202 is flange-connected to the inlet of the first pipe 201 as shown in FIG. 1, and the outlet of the second pipe 202 is connected to the inlet of the third pipe 203 as shown in FIGS. 1 and 2. is flange connected to. Note that, as shown in FIG. 1, a residual pressure relief valve PV is attached to the second pipe 202.

The inlet of the third pipe 203 is flange connected to the outlet of the second pipe 202 as shown in FIGS. 1 and 2, and the outlet of the third pipe 203 is connected to the fourth pipe as shown in FIGS. 1 and 3. A flange connection is made to the inlet of 204.

The inlet of the fourth pipe 204 is flange-connected to the outlet of the third pipe 203, as shown in FIGS. 1 and 3. As shown in FIGS. 1 and 3, the fourth piping 204 has three outlets: the upper end, the middle part located below the upper end, and the lower part below the middle part. It is formed. The outlet at the upper end of the fourth pipe 204 is connected to the inlet of the injection part 205, as shown in FIGS. 3 and 4. The outlet of the intermediate portion of the fourth pipe 204 is connected to the inlet of the injection part 206, as shown in FIGS. 3 and 4. The lower outlet of the fourth pipe 204 is connected to the inlet of the injection part 207, as shown in FIGS. 3 and 4.

The inlet of the injection part 205 is connected to the outlet at the upper end of the fourth pipe 204, as shown in FIGS. 3 and 4, and the end of the injection part 205 on the exit side is connected to the liquid distribution part as described above. It is inserted into the inside of the connection pipe CP6 of the second flow section 120 of No. 100. The inlet of the injection part 206 is connected to the outlet of the intermediate part of the fourth pipe 204 as shown in FIGS. 3 and 4, and the end of the injection part 206 on the exit side is connected to the liquid to be treated flow part as described above. It is inserted into the connecting pipe CP8 of the second flow section 120 of No. 100. Note that the hydrogen peroxide and nitric acid flowing through the injection section 205 are added to the liquid to be treated that has flowed into the connection pipe CP6 of the second distribution section 120 of the liquid distribution section 100, and the hydrogen peroxide and nitric acid flowing through the injection section 206 are is added to the liquid to be treated that has flowed into the connection pipe CP8 of the second circulation part 120 of the liquid to be treated part 100. The inlet of the injection part 207 is connected to the lower outlet of the fourth pipe 204 as shown in FIGS. 3 and 4, and the end of the injection part 207 on the outlet side is connected to the connecting pipe of the reactor 300 as described above. It is inserted into the inside of 303. Note that hydrogen peroxide and nitric acid flowing through the injection part 207 are added to the liquid to be treated flowing out from the first reaction pipe 301 of the reactor 300.

3. Reactor The reactor 300 is made of metal (for example, titanium (titanium alloy or pure titanium), etc.), and as shown in FIG. and a connecting pipe 303. These components will be explained in detail below.

A catalyst is fixed inside the first reaction pipe 301. The catalyst is, for example, a Fenton catalyst (e.g., an iron compound such as ferrous sulfate, a copper compound such as copper oxide, a mixture of copper and a metal element other than copper (e.g., nickel), etc.), and may be in the form of granules, pellets, etc. It has a shape such as a honeycomb structure or a honeycomb structure. Further, as shown in FIG. 4, the inlet of the first reaction pipe 301 is flange-connected to the outlet of the connection pipe CP9 of the second flow section 120 of the liquid flow section 100, and the outlet of the first reaction pipe 301 is As shown in FIG. 4, it is flange-connected to the inlet of the connecting pipe 303.

A catalyst is fixed inside the second reaction pipe 302. The catalyst is, for example, a Fenton catalyst (e.g., an iron compound such as ferrous sulfate, a copper compound such as copper oxide, a mixture of copper and a metal element other than copper (e.g., nickel), etc.), and may be in the form of granules, pellets, etc. It has a shape such as a honeycomb structure or a honeycomb structure. Further, the inlet of the second reaction pipe 302 is flange-connected to the outlet of the connecting pipe 303 as shown in FIG. A flange connection is made to the inlet of the left side pipe 401 of the section 400.

The connecting pipe 303 connects the first reaction pipe 301 and the second reaction pipe 302, as shown in FIGS. 3 and 4. Note that, as described above, the end on the outlet side of the injection part 207 of the additive liquid distribution part 200 is inserted into the inside of the connection pipe 303.

4. Processing liquid distribution section The processing liquid distribution section 400 is for guiding the liquid to be treated (hereinafter referred to as "processing liquid") after harmful substances have been decomposed to the outside, and is made of metal (for example, stainless steel). As shown in FIGS. 1, 2, and 4, it is mainly composed of a left side pipe 401, front side pipes 402 to 407, and a drain pipe 408. These components will be explained in detail below.

The left side pipe 401 is arranged on the left side of the organic matter decomposition apparatus 1, as shown in FIGS. 1, 2, and 4. The inlet of the left pipe 401 is flange-connected to the outlet of the second reaction pipe 302 of the reactor 300, as shown in FIGS. 1, 2, and 4, and the outlet of the left pipe 401 is It is flange-connected to the inlet of the front pipe 402 so that the front pipe 402 can be opened.

The front pipes 402 to 407 are arranged in front of the rear pipes BP1 to BP5 of the liquid distribution section 100, as shown in FIGS. 1 to 4. The front pipes 403 to 407 have a substantially cylindrical shape with a left end surface and a right end surface (see FIG. 1). Openings are formed in these left and right end surfaces. The front piping FP1 of the first distribution section 110 of the liquid distribution section 100 to be treated is inserted through this opening of the front piping 407 and arranged inside the front piping 407. The front piping FP2 of the first distribution section 110 of the liquid distribution section 100 to be treated is inserted through this opening of the front piping 406 and arranged inside the front piping 406. The front piping FP3 of the first distribution section 110 of the liquid distribution section 100 to be treated is inserted through this opening of the front piping 405 and arranged inside the front piping 405. The front piping FP4 of the first distribution section 110 of the liquid distribution section 100 to be treated is inserted through this opening of the front piping 404 and arranged inside the front piping 404. The front piping FP5 of the first distribution section 110 of the liquid distribution section 100 to be treated is inserted through this opening of the front piping 403 and arranged inside the front piping 403. Further, as shown in FIG. 1, in the front piping 403, 405, 407, the inlet forming part protrudes downward from the right end, and the outlet forming part protrudes upward from the left end. In this case, the inlet forming part projects downward from the left end, and the outlet forming part projects upward from the right end.

The inlet of the front piping 402 is flange-connected to the outlet of the left-hand piping 401 as shown in FIGS. 1 and 2, and the outlet of the front piping 402 is flange-connected to the inlet of the front piping 403 as shown in FIG. Connected. The inlet of the front pipe 403 is flange-connected to the outlet of the front pipe 402, as shown in FIG. 1, and the outlet of the front pipe 403 is flange-connected to the inlet of the front pipe 404, as shown in FIGS. 1 and 3. Ru. The inlet of the front pipe 404 is flange connected to the outlet of the front pipe 403 as shown in FIGS. 1 and 3, and the outlet of the front pipe 404 is connected to the inlet of the front pipe 405 as shown in FIGS. 1 and 2. Flange connected. The inlet of the front pipe 405 is flange connected to the outlet of the front pipe 404 as shown in FIGS. 1 and 2, and the outlet of the front pipe 405 is connected to the inlet of the front pipe 406 as shown in FIGS. 1 and 3. Flange connected. The inlet of the front pipe 406 is flanged to the outlet of the front pipe 405 as shown in FIGS. 1 and 3, and the outlet of the front pipe 406 is flanged to the inlet of the front pipe 407 as shown in FIG. Ru. As shown in FIG. 1, the inlet of the front pipe 407 is flanged to the outlet of the front pipe 406, and the outlet of the front pipe 407 is flanged to the inlet of the drain pipe 408.

The inlet of the drain pipe 408 is flange-connected to the outlet of the front pipe 407, as shown in FIG. 1, and the outlet of the drain pipe 408 is used as a discharge port for the processing liquid. Note that, as shown in FIGS. 1 to 4, a second air vent valve AV2 and a back pressure valve BV are attached to the drain pipe 408.

5. Pressure Pump for Processed Liquid The pressurization pump PO1 for processed liquid distributes the processed liquid in the processed liquid tank through the liquid supply pipe LP1 of the first distribution section 110 of the processed liquid distribution section 100. It plays the role of distributing information to the department 100. Note that the pressurizing pump PO1 for the liquid to be treated is connected to a control device.

6. Additive Liquid Pressure Pump The additive liquid pressure pump PO2 plays the role of distributing hydrogen peroxide and nitric acid in the additive liquid tank to the additive liquid distribution section 200 via the first pipe 201 of the additive liquid distribution section 200. ing. Note that the additive liquid pressurizing pump PO2 is connected to the control device.

7. Safety Valve The safety valve SV has the role of releasing the pressure inside (inside the system) of the treated liquid distribution section 100, the additive liquid distribution section 200, the reactor 300, and the processing liquid distribution section 400, and is shown in FIG. As such, it is attached to the left side piping LP2 of the first distribution section 110 of the liquid distribution section 100 to be treated.

8. First air vent valve The first air vent valve AV1 has the role of discharging air accumulated in the system to the outside, and as shown in FIGS. It is attached to the right side pipe RP1 of 110.

9. Second Air Vent Valve The second air vent valve AV2 has the role of discharging air accumulated in the system to the outside and releasing the pressure in the system, and as shown in FIGS. 1, 2, and 4. , is attached to the drain pipe 408 of the processing liquid distribution section 400.

10. Residual Pressure Release Valve The residual pressure release valve PV plays a role of releasing pressure within the system, and is attached to the second pipe 202 of the additive liquid distribution section 200, as shown in FIG.

11. Back Pressure Valve The back pressure valve BV plays the role of preventing the processing liquid from being discharged in an amount larger than a specified amount from the outlet of the drain pipe 408 of the processing liquid distribution section 400, and keeping the pressure in the system constant. , as shown in FIGS. 2 and 4, is attached to the drain pipe 408 of the processing liquid distribution section 400.

12. Heater The heater (not shown) is, for example, a ribbon heater or the like, and is attached to the outer surface of the rear piping BP1 to BP5 of the liquid distribution section 100 and the outer surface of the third piping 203 of the additive liquid distribution section 200. . Note that the heater is connected to a control device.

13. Control Device As described above, the control device (not shown) is connected to the liquid to be treated pressurizing pump PO1, the additive liquid pressurizing pump PO2, the heater, etc., and controls the on/off and output of these power supplies.

<Description of organic matter decomposition method using the organic matter decomposition device according to the embodiment of the present invention>
An organic matter decomposition method using the organic matter decomposition device 1 will be described below.

First, the pressurizing pump PO1 for the liquid to be treated causes the liquid to be treated containing harmful substances to flow into the liquid supply pipe LP1 of the first distribution part 110 of the liquid to be treated part 100. At this time, the pressure in the system is preferably set within the range of 1 MPa or more and 2.2 MPa or less, and preferably set within the range of 1.5 MPa or more and 2.0 MPa or less, by the back pressure valve BV. More preferred. The liquid to be treated is supplied to the first distribution section 110 of the liquid distribution section 100 through liquid supply piping LP1 → left side piping LP2 → front side piping FP1 → connection piping CP1 → front side piping FP2 → connection piping CP2 → front side piping FP3 → connection. Piping CP3 → Front piping FP4 → Connecting piping CP4 → Front piping FP5 → Right piping RP1 → Rear piping BP1 → Connecting piping CP5 → Rear piping BP2 → Connecting piping CP6 of the second distribution section 120 of the liquid distribution section 100 flow inside these in order. The liquid to be treated is heated by the heating section while flowing through the rear piping BP1, BP2 of the liquid to be treated distribution section 100.

Note that when the liquid to be treated flows into the connection pipe CP6 of the second distribution part 120 of the liquid to be treated part 100, the hydrogen peroxide and nitric acid flowing out from the injection part 205 of the additive liquid distribution part 200 flow into the liquid to be treated. added to. The liquid to be treated after the addition of hydrogen peroxide and nitric acid is transferred from the rear pipe BP3 of the second distribution section 120 of the liquid distribution section 100 to the connecting pipe CP7 to the rear piping BP4 to the connecting pipe CP8 to the rear. It flows inside these in the order of side pipe BP5→connection pipe CP9. The treated liquid to which hydrogen peroxide and nitric acid have been added is heated by the heating section while flowing through the rear piping BP3, BP4, BP5 of the treated liquid distribution section 100. Note that when the treated liquid to which hydrogen peroxide and nitric acid have been added flows into the connection pipe CP8 of the second distribution part 120 of the treated liquid distribution part 100, the liquid flows from the injection part 206 of the additive liquid distribution part 200. The hydrogen peroxide and nitric acid that flowed out are further added to the liquid to be treated. Hydrogen peroxide and nitric acid are flowed into the first pipe 201 of the additive liquid distribution section 200 by the additive liquid pressurizing pump PO2, and are transferred from the first piping 201 to the second piping 202 to the third piping 203 of the additive liquid distribution section 200. → Fourth pipe 204 → Injection parts 205, 206, and 207 in this order. Further, hydrogen peroxide and nitric acid are heated by the heating section while flowing through the third pipe 203 of the additive liquid distribution section 200. That is, heated hydrogen peroxide and nitric acid are added to the liquid to be treated.

After hydrogen peroxide and nitric acid have been added, the liquid to be treated is transferred from the connection pipe CP9 of the second circulation part 120 of the liquid distribution part 100 to the first reaction pipe 301 of the reactor 300→connection pipe 303→ It flows inside these in order of the second reaction pipe 302. When the liquid to be treated comes into contact with the catalyst in the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, harmful substances contained in the liquid to be treated are decomposed. Note that when the liquid to be treated is in contact with the catalyst in the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated is in the range of 0°C or more and 200°C or less. It is preferably within the range of 50°C or more and 200°C or less, more preferably within the range of 100°C or more and 200°C or less, and more preferably within the range of 150°C or more and 200°C or less. It is more preferable that the temperature is in the range of 180°C or more and 200°C or less.

Note that when the treated liquid to which hydrogen peroxide and nitric acid have been added is flowing through the connection pipe CP9 of the reactor 300, the hydrogen peroxide and nitric acid that flowed out from the injection part 207 of the additive liquid distribution part 200 also Further added to the liquid to be treated.

The processing liquid is then transferred from the second reaction pipe 302 of the reactor 300 to the left pipe 401 of the processing liquid distribution section 400 → front pipe 402 → front pipe 403 → front pipe 404 → front pipe 405 → front pipe 406 → front pipe 407. →Flows inside these in the order of drainage pipe 408. In addition, in more detail, the inside of the front pipe 403 is the inside of the front pipe 403 and the outside of the front pipe FP5 of the liquid distribution section 100, and the inside of the front pipe 404 is the inside of the front pipe 404 and the outside of the front pipe FP5 of the liquid distribution section 100. It is outside the front piping FP4 of the liquid distribution section 100, the inside of the front piping 405 is inside the front piping 405 and the outside of the front piping FP3 of the liquid distribution section 100, and the inside of the front piping 406 is inside the front piping FP4. 406 and the outside of the front pipe FP2 of the liquid to be processed portion 100, and the inside of the front pipe 407 is the inside of the front pipe 407 and the outside of the front pipe FP1 of the liquid to be processed portion 100. Finally, the processing liquid is discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400.

<Characteristics of the organic substance decomposition method according to the embodiment of the present invention>
(1)
In the organic substance decomposition method according to the embodiment of the present invention, hydrogen peroxide and nitric acid are added to a liquid to be treated containing organic substances, and the liquid to be treated is transferred to the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300. is brought into contact with the catalyst inside. Therefore, in this organic substance decomposition method, hydrogen peroxide is added to a liquid to be treated containing organic substances, and the liquid to be treated is brought into contact with the catalyst in the first reaction pipe 301 and second reaction pipe 302 of the reactor 300 to remove organic substances. The cost of decomposing organic matter can be kept as low as possible compared to when decomposing organic matter.

(2)
In the organic substance decomposition method according to the embodiment of the present invention, the liquid to be treated after hydrogen peroxide and nitric acid is added comes into contact with the catalyst in the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300. In this state, the temperature of the liquid to be treated is within the range of 0°C or more and 200°C or less. Therefore, in this organic substance decomposition method, the decomposition of organic substances can be further promoted without deactivating the catalyst.

<Modified example>
(A)
In the organic matter decomposition apparatus 1 according to the previous embodiment, the heating section is connected to the outer surface of the rear piping BP1, BP2, BP3, BP4, BP5 of the liquid distribution section 100 and the third piping 203 of the additive liquid distribution section 200. It was attached to the outside. However, when the treated liquid to which hydrogen peroxide and nitric acid have been added comes into contact with the catalyst in the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the treated liquid reaches 100°C. As long as the temperature is within the range of 200°C or less, the heating part may be attached to the outer surface of at least one of these pipes, or the rear pipes BP1, BP2, BP3, It may be attached to at least one outer surface other than BP4, BP5, it may be attached to at least one outer surface other than the third pipe 203 of the additive liquid distribution section 200, or it may be attached to the outer surface of the reactor 300. It's okay.

(B)
Although not mentioned in the organic matter decomposition device 1 according to the previous embodiment, the number of pipes that constitute the treated liquid distribution section 100, the additive liquid distribution section 200, the reactor 300, and the treatment liquid distribution section 400 is not limited.

(C)
In the organic matter decomposition apparatus 1 according to the previous embodiment, it was said that the pressure in the system is preferably set within the range of 1 MPa or more and 2.2 MPa or less by the back pressure valve BV. However, pressure may not be applied to the system by the back pressure valve BV.

(D)
In the organic substance decomposition apparatus 1 according to the previous embodiment, the liquid to be treated after hydrogen peroxide and nitric acid is added comes into contact with the catalyst in the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300. In this state, the temperature of the liquid to be treated is preferably within the range of 0°C or more and 200°C or less. However, if the catalyst is not deactivated or the organic matter is sufficiently decomposed, the temperature of the liquid to be treated should be higher than 200°C under the same conditions (for example, within the range of 200°C to 400°C, 200°C (e.g., within a range of more than 300°C or less).

(E)
Although not mentioned in the organic matter decomposition apparatus 1 according to the previous embodiment, a catalyst may also be fixed inside the connecting pipe 303 of the reactor 300.

(F)
In the previous embodiment, decomposition of organic matter by the organic matter decomposition method according to the present invention was realized by using the organic matter decomposition device 1. However, decomposition of organic matter by the organic matter decomposition method according to the present invention may be realized without using the organic matter decomposition device 1. For example, hydrogen peroxide and nitric acid may be added to a liquid to be treated containing organic matter, and the liquid to be treated and the catalyst may be put into a container all at once. The liquid to be treated, to which hydrogen peroxide and nitric acid have been added, may be heated by a heating unit attached to the outer surface of the container. Alternatively, at least one of the liquid to be treated containing organic matter, hydrogen peroxide, and nitric acid may be heated in advance before hydrogen peroxide and nitric acid are added to the liquid to be treated containing organic matter.

(G)
In the organic matter decomposition apparatus 1 according to the previous embodiment, hydrogen peroxide and nitric acid flowed through the additive liquid distribution section 200 and were added to the liquid to be treated. However, the additive liquid flow section 200 may not be provided, and a hydrogen peroxide flow section through which only hydrogen peroxide flows and a nitric acid flow section through which only nitric acid flows may be provided. Then, the hydrogen peroxide flowing out from the outlet of the hydrogen peroxide flow section is transferred to the inside of the connection pipes CP6 and CP8 of the second flow section 120 of the liquid flow section 100 and the inside of the connection pipe CP9 of the reactor 300. The nitric acid added to the liquid and flowing out from the outlet of the nitric acid flow section causes the liquid to be treated to flow inside the connecting pipes CP6 and CP8 of the second flow section 120 of the liquid flowing section 100 and inside the connecting pipe CP9 of the reactor 300. may be added to.

(H)
In the organic matter decomposition apparatus 1 according to the previous embodiment, the first air vent valve AV1 is attached to the right pipe RP1 of the first distribution section 110 of the liquid distribution section 100, and the second air vent valve AV2 is attached to the right side pipe RP1 of the first distribution section 110 of the liquid distribution section 100. It was attached to the drain pipe 408 of the section 400. However, the piping to which the air vent valve is attached is not limited to these pipings. That is, an air vent valve may be attached to at least one of the pipes forming the treated liquid distribution section 100, the additive liquid distribution section 200, and the processing liquid distribution section 400.

(I)
Although not mentioned in the organic matter decomposition device 1 according to the previous embodiment, at least one of the pipes constituting the treated liquid distribution section 100, the additive liquid distribution section 200, and the treatment liquid distribution section 400 may be made of titanium. good. For example, all of the piping of the liquid distribution section 100, the additive liquid distribution section 200, and the treatment liquid distribution section 400 may be made of titanium, or the connection piping CP8 and the rear piping BP5 of the liquid distribution section 100 may be made of titanium. The connecting pipe CP9 may be made of titanium, and the first pipe 201, the second pipe 202, the third pipe 203, and the fourth pipe 204 of the additive liquid distribution section 200 may be made of titanium.

Note that the above modifications may be applied alone or in combination.

<Examples and comparative examples>
EXAMPLES Below, Examples and Comparative Examples will be shown to explain the present invention in more detail, but the present invention is not limited to these Examples.

Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. Then, as shown in Table 1, the liquid to be treated having a total organic carbon concentration (TOC) of 1007.4 mg/L and a concentration of 1,4-dioxane of 1600 mg/L is supplied to the liquid supply pipe of the liquid to be treated flow section 100. Nitric acid and hydrogen peroxide were made to flow into the first pipe 201 of the additive liquid flow section 200 so that the concentrations were 25 mM of nitric acid and 100 mM of hydrogen peroxide. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide and nitric acid are added varies within a range of 180°C or more and 200°C or less. I confirmed that In addition, in a state where the liquid to be treated after hydrogen peroxide and nitric acid has been added is flowing into the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, there are almost no bubbles in the reactor 300. We have confirmed that this has not occurred. When the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 402.5 mg/L, and the 1,4-dioxane concentration was 402.5 mg/L. was 70 mg/L. The results show that the TOC removal rate was 60% and the 1,4-dioxane decomposition rate was 95.6% (see Table 1).

Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. Then, as shown in Table 1, the liquid to be treated having a total organic carbon concentration (TOC) of 1007 mg/L and a concentration of 1,4-dioxane of 1600 mg/L is introduced into the liquid supply pipe LP1 of the liquid distribution part 100. Nitric acid and hydrogen peroxide were flowed into the first pipe 201 of the additive liquid flow section 200 so that the concentrations were 25 mM of nitric acid and 150 mM of hydrogen peroxide. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide and nitric acid are added varies within a range of 180°C or more and 200°C or less. I confirmed that In addition, in a state where the liquid to be treated after hydrogen peroxide and nitric acid has been added is flowing into the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, there are almost no bubbles in the reactor 300. We have confirmed that this has not occurred. When the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 154.9 mg/L, and the 1,4-dioxane concentration was 154.9 mg/L. was 6 mg/L. The results show that the TOC removal rate was 84.6% and the 1,4-dioxane decomposition rate was 99.6% (see Table 1).

Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. Then, as shown in Table 1, the liquid to be treated having a total organic carbon concentration (TOC) of 1022.2 mg/L and a concentration of 1,4-dioxane of 1700 mg/L is supplied to the liquid supply pipe of the liquid distribution part 100. Nitric acid and hydrogen peroxide were flowed into the first pipe 201 of the additive liquid flow section 200 so that the concentrations were 40 mM of nitric acid and 150 mM of hydrogen peroxide. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide and nitric acid are added varies within a range of 180°C or more and 200°C or less. I confirmed that In addition, in a state where the liquid to be treated after hydrogen peroxide and nitric acid has been added is flowing into the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, there are almost no bubbles in the reactor 300. We have confirmed that this has not occurred. When the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 176.4 mg/L, and the 1,4-dioxane concentration was 176.4 mg/L. was 16 mg/L. The results show that the TOC removal rate was 82.7% and the 1,4-dioxane decomposition rate was 99.1% (see Table 1).

Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. Then, as shown in Table 1, the liquid to be treated having a total organic carbon concentration (TOC) of 1029.6 mg/L and a concentration of 1,4-dioxane of 1800 mg/L is supplied to the liquid supply pipe of the liquid distribution part 100. Nitric acid and hydrogen peroxide were flowed into the first pipe 201 of the additive liquid flow section 200 so that the concentrations were 14 mM of nitric acid and 200 mM of hydrogen peroxide. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide and nitric acid are added varies within a range of 180°C or more and 200°C or less. I confirmed that In addition, in a state where the liquid to be treated after hydrogen peroxide and nitric acid has been added is flowing into the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, there are almost no bubbles in the reactor 300. We have confirmed that this has not occurred. When the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 401 mg/L, and the 1,4-dioxane concentration was 78 mg. /L. The results show that the TOC removal rate was 61.1% and the 1,4-dioxane decomposition rate was 95.7% (see Table 1).

Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. As shown in Table 1, a liquid to be treated having a total organic carbon concentration (TOC) of 1020.6 mg/L and a 1,4-dioxane concentration of 1600 mg/L is supplied to the liquid supply pipe of the liquid to be treated flow section 100. Nitric acid and hydrogen peroxide were allowed to flow into the first pipe 201 of the additive liquid flow section 200 so that the resulting amounts were 25 mM of nitric acid and 200 mM of hydrogen peroxide. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide and nitric acid are added varies within a range of 180°C or more and 200°C or less. I confirmed that In addition, in a state where the liquid to be treated after hydrogen peroxide and nitric acid has been added is flowing into the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, there are almost no bubbles in the reactor 300. We have confirmed that this has not occurred. When the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 14.8 mg/L, and the 1,4-dioxane concentration was 14.8 mg/L. was 0.06 mg/L. The results show that the TOC removal rate is 98.5% and the 1,4-dioxane decomposition rate is approximately 100% (≈99.99...%) (see Table 1).

(Comparative example 1)
Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. Then, as shown in Table 1, the liquid to be treated having a total organic carbon concentration (TOC) of 1034.6 mg/L is flowed into the liquid supply pipe LP1 of the liquid to be treated flow section 100, and 100 mM of hydrogen peroxide is added to the liquid to be treated. Hydrogen peroxide was allowed to flow into the first pipe 201 of the additive liquid flow section 200 so that In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide is added changes within a range of 180°C or more and 200°C or less. It was confirmed. Then, when the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 549.3 mg/L. As a result, it was found that the TOC removal rate was 46.9% (see Table 1).

(Comparative example 2)
Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. As shown in Table 1, the liquid to be treated having a total organic carbon concentration (TOC) of 1021.8 mg/L and a concentration of 1,4-dioxane of 1900 mg/L is supplied to the liquid supply pipe of the liquid to be treated flow section 100. Hydrogen peroxide was caused to flow into the first pipe 201 of the additive liquid flow section 200 so that the hydrogen peroxide concentration was 300 mM. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide is added changes within a range of 180°C or more and 200°C or less. It was confirmed. Further, in a state where the liquid to be treated after hydrogen peroxide has been added is flowing into the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, many bubbles are generated in the reactor 300. I confirmed that When the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 122.5 mg/L, and the 1,4-dioxane concentration was 122.5 mg/L. was 160 mg/L. The results show that the TOC removal rate was 88% and the 1,4-dioxane decomposition rate was 91.6% (see Table 1).

(Comparative example 3)
Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. Then, as shown in Table 1, the liquid to be treated having a total organic carbon concentration (TOC) of 1024.2 mg/L was flowed into the liquid supply pipe LP1 of the liquid to be treated distribution section 100, and 10 mM of sulfuric acid and peroxide were added. Sulfuric acid and hydrogen peroxide were flowed into the first pipe 201 of the additive liquid flow section 200 so that the hydrogen concentration was 100 mM. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide and sulfuric acid are added varies within a range of 180°C or more and 200°C or less. I confirmed that Then, when the processing liquid discharged from the outlet of the drain pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 755.1 mg/L. As a result, it was found that the TOC removal rate was 26.3% (see Table 1).

(Comparative example 4)
Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. Then, as shown in Table 1, the liquid to be treated whose total organic carbon concentration (TOC) is 1025.6 mg/L is flowed into the liquid supply pipe LP1 of the liquid to be treated flow section 100, so that the concentration of nitric acid is 120 mM. Then, nitric acid was allowed to flow into the first pipe 201 of the additive liquid flow section 200. Then, it is confirmed that the temperature of the liquid to be treated after nitric acid is added changes within the range of 180°C or more and 200°C or less in the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300. confirmed. Then, when the processing liquid discharged from the outlet of the drain pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 1, the total organic carbon concentration was 972.8 mg/L. As a result, it was found that the TOC removal rate was 5.1% (see Table 1).

(Comparative example 5)
Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. As shown in Table 2, a liquid to be treated having a total organic carbon concentration (TOC) of 34,000 mg/L, a phenol concentration of 29,000 mg/L, and a formaldehyde concentration of 2,300 mg/L is supplied to the liquid to be treated flow section 100. Hydrogen peroxide was caused to flow into the first pipe 201 of the additive liquid flow section 200 so that the hydrogen peroxide concentration was 300 mM. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide is added changes within a range of 180°C or more and 200°C or less. It was confirmed. When the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 2, the total organic carbon concentration was 17,350 mg/L, the phenol concentration was 9,600 mg/L, Formaldehyde concentration was 970 mg/L. The results show that the TOC removal rate was 49%, the phenol decomposition rate was 66.9%, and the formaldehyde decomposition rate was 57.8% (see Table 2).

(Comparative example 6)
Organic matter contained in the liquid to be treated was decomposed using the organic matter decomposition device 1. A copper-nickel catalyst was used as the catalyst, and the pressure in the system was set at 2 MPa using a back pressure valve BV, and then electricity was applied to the heating section. Then, as shown in Table 3, a liquid to be treated having a toluene concentration of 1 mg/L, an ethanol concentration of 40 mg/L, and a N,N-dimethylformamide concentration of 100 mg/L is supplied to the liquid to be treated flowing section 100. Hydrogen peroxide was caused to flow into the first pipe 201 of the additive liquid distribution section 200 so that the hydrogen peroxide concentration was 300 mM. In the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, the temperature of the liquid to be treated after hydrogen peroxide is added changes within a range of 180°C or more and 200°C or less. It was confirmed. When the processing liquid discharged from the outlet of the drainage pipe 408 of the processing liquid distribution section 400 was analyzed, as shown in Table 3, the toluene concentration was 0.12 mg/L, the ethanol concentration was 330 mg/L, and the N ,N-dimethylformamide concentration was 40 mg/L or less. The results show that the toluene decomposition rate is 88% and the N,N-dimethylformamide decomposition rate is 60%. It is assumed that the amount of ethanol is increased due to reaction by-products (see Table 3).

[Comparative verification of Examples and Comparative Examples]
Example 2 and Comparative Example 2 will be compared and verified regarding the cost of decomposing organic matter. In addition, in these examples, nitric acid (62.5%) which is 900 yen/500 mL (1.8 yen/mL), hydrogen peroxide (32.8%) which is 1850 yen/500 mL (3.7 yen/mL) %) is used. As in Example 2, when 25mM (0.025mol/L) nitric acid and 150mM (0.15mol/L) hydrogen peroxide are caused to flow into the first pipe 201 of the additive liquid flow section 200, the following From the calculation formula, 54.7 yen is required for 1 L of the liquid to be treated.
Nitric acid: 1.8 yen/mL x 63 g/mol x 0.025 mol/L x 100 ÷ 62.5% ÷ specific gravity 1.38 ≒ 3.3 yen/L
Hydrogen peroxide: 3.7 yen/mL x 34 g/mol x 0.15 mol/L x 100 ÷ 32.8% ÷ specific gravity 1.12 ≒ 51.4 yen/L
Total: 3.3 yen/L + 51.4 yen/L = 54.7 yen/L

As in Comparative Example 2, when 300mM (0.3mol/L) of hydrogen peroxide is flowed into the first pipe 201 of the additive liquid distribution section 200, the calculation formula below shows that 300mM (0.3mol/L) of hydrogen peroxide is Therefore, 102.8 yen is required.
Hydrogen peroxide: 3.7 yen/mL x 34 g/mol x 0.3 mol/L x 100 ÷ 32.8% ÷ specific gravity 1.12 ≒ 102.8 yen/L

From the above, by adding hydrogen peroxide and nitric acid to the liquid to be treated containing organic matter and bringing the liquid to be treated into contact with the catalyst, half the amount of hydrogen peroxide that would be required when nitric acid is not added to the liquid to be treated can be reduced. It has been revealed that hydrogen peroxide has the same or better ability to decompose organic matter than when nitric acid is not added, and that the cost of decomposing organic matter can be reduced by about half.

Next, Examples 1 to 5 and Comparative Example 2 will be compared and verified to see if bubbles are generated in the reactor 300. In Examples 1 to 5, as described above, in a state where the liquid to be treated after adding hydrogen peroxide and nitric acid is flowing into the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300. It has been confirmed that almost no bubbles are generated within the reactor 300. On the other hand, in Comparative Example 2, in a state where the liquid to be treated after adding hydrogen peroxide is flowing into the first reaction pipe 301 and the second reaction pipe 302 of the reactor 300, It has been confirmed that many bubbles are generated. When a large number of bubbles are generated in the reactor 300, there is a possibility that the liquid to be treated cannot flow into the reactor 300 or that the treated liquid cannot flow out from the reactor 300. Therefore, the organic matter decomposition method according to the present invention can reduce the occurrence of such a fear as much as possible.

1 Organic matter decomposition device 100 To-be-treated liquid distribution section (first supply section)
200 Additive liquid distribution section (second supply section)
300 reactor

Claims (6)

Hydrogen peroxide and nitric acid are added to a liquid to be treated containing organic matter, and the liquid to be treated is brought into contact with a catalyst.
Organic matter decomposition method. The temperature of the liquid to be treated after adding the hydrogen peroxide and the nitric acid is within a range of 0°C or more and 200°C or less,
The organic substance decomposition method according to claim 1. a first supply section that supplies a liquid to be treated containing organic matter to the catalyst;
An organic matter decomposition device comprising: a second supply unit that supplies hydrogen peroxide and nitric acid to the liquid to be treated before the liquid to be treated reaches the catalyst. further comprising a reactor in which the catalyst is fixed,
The first supply part has an outlet connected to the inlet of the reactor,
The organic matter decomposition apparatus according to claim 3, wherein the second supply section has an outlet connected to the first supply section. further comprising a heating unit that heats at least one of the first supply unit, the second supply unit, and the reactor;
The organic matter decomposition device according to claim 4. The heating section is configured such that the temperature of the liquid to be treated after adding the hydrogen peroxide and the nitric acid is 0° C. in a state where the liquid to be treated after adding the hydrogen peroxide and the nitric acid is in contact with the catalyst. heating at least one of the first supply section, the second supply section, and the reactor so that the temperature is within a range of 200° C. or less;
The organic matter decomposition device according to claim 5.

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