JP2022165529A - Wastewater final treatment apparatus for highly concentrated persistent organic matter, systems using the apparatus, and wastewater final treatment methods for highly concentrated persistent organic matter - Google Patents

Abstract

To provide a waste water final treatment apparatus for highly concentrated persistent organic matter using ozone microbubbles and/or ozone nanobubbles, and a system and a method using the apparatus.SOLUTION: A wastewater final treatment apparatus 1 for highly concentrated persistent organic matter includes an ozone generator 2, an ozone decomposition reactor 3, an ozone-ultraviolet decomposition reactor 4, and an ozone catalytic reactor 5, in which the ozone decomposition reactor comprises an ozone decomposition reaction tank, a raw water inlet, a first microbubble generator, an ejector pump, a first crushing tower 35, a first circulation pump, and a first activated carbon tower 37. The ozone-ultraviolet decomposition reactor has an ozone-ultraviolet decomposition reaction tank, a UV irradiator, a second microbubble generator, a second crushing tower 45, a third circulation pump, and a second activated carbon tower 47 there inside. The ozone catalytic reactor has an ozone catalytic decomposition tank, a third microbubble generator, a fourth circulation pump, a third crushing tower 54, a fifth circulation pump, and a third activated carbon tower 56.SELECTED DRAWING: Figure 1

Description

The present invention provides high-concentration persistent organic matter using water containing ozone gas-containing microbubbles (hereinafter referred to as "ozone microbubbles") and/or ozone gas-containing nanobubbles (hereinafter referred to as "ozone nanobubbles"). The present invention relates to a wastewater final treatment device, a system using the device, and a final treatment method for wastewater containing highly concentrated persistent organic matter.

Ozone has a strong oxidizing power next to fluorine, and is used for sterilization, virus inactivation, deodorization, decolorization, removal of organic matter, etc. in fields such as medicine, food, agriculture, livestock, and semiconductor product cleaning. It is generally well known that Furthermore, it is known that ozone is used not only in the fields mentioned above but also in wastewater treatment fields such as industry, agriculture, and living.

In the field of wastewater treatment, the advantage of using ozone is that it is possible to oxidize not only metals but also organic substances as described above. For example, Japanese Patent No. 3468414 (Patent Literature 1) discloses a method and system for treating wastewater containing machinery using its properties.

In the method and system described in Patent Document 1, wastewater containing organic substances and persistent substances is treated with ozone in a two-stage negative pressure separation tank, and after the ozone treatment, further microbial aeration and precipitation separation are performed. It is to do. When ozonating in a negative pressure type separation tank, that is, when waste water and ozone are condensed and mixed in a gas-liquid manner, vortexing is used to efficiently ozonize.

However, in the method and system described in Patent Document 1, even if the wastewater is treated with ozone, sterilization is sufficient, but the persistent substances only change from persistent substances to easily degradable substances. depends on microbial aeration and sedimentation separation. Moreover, it is unknown whether waste water with high BOD (biochemical oxygen demand) or COD (chemical oxygen demand) values, that is, waste water containing a high concentration of organic matter can be treated.

Here, when treating wastewater using ozone, microbubbles of the order of several tens to several hundred μm containing ozone gas in the wastewater (microbubbles) and/or microbubbles of the order of several tens to several hundred nm containing ozone gas A method of treating organic matter in wastewater using the adsorption capacity of the microbubbles and / or nanobubbles, for example, Japanese Patent Application Laid-Open No. 2012-106211 (Patent Document 2), Japanese Patent Application Laid-Open No. 2012-106212 It is disclosed in the publication (Patent Document 3) and Japanese Patent Application Laid-Open No. 2012-106213 (Patent Document 4). The method described in Patent Document 2 is a wastewater pretreatment method that enables subsequent wastewater treatment to be performed efficiently by removing high-molecular weight (molecular weight of 10,000 or more) organic fine solid substances. Further, in the method described in Patent Document 3, organic matter in wastewater is decomposed by ozone microbubbles and free radicals generated by the forcible crushing of ozone microbubbles, and is further treated with an inorganic coagulant to render it harmless. Wastewater treatment is carried out by depositing it as a precipitate. In addition, the method described in Patent Document 4 passes the final residual organic matter that could not be completely treated by the method described in Patent Document 3, that is, the organic fine solid substance together with ozone microbubbles and/or ozone nanobubbles through activated carbon. It is to process by letting The methods described in Patent Documents 2 to 4 are effective for relatively high-concentration wastewater with a COD value of 1000 mg/L or more.

Japanese Patent No. 3468414 JP 2012-106211 A JP 2012-106212 A JP 2012-106213 A Japanese Patent No. 6635444

However, in the method and system described in Patent Document 1, as described above, the persistent substance only changes from persistent to easily degradable, and ultimately depends on microbial aeration and sedimentation separation. do. In addition, it is unclear whether or not it is possible to decompose persistent substances such as acrylic wastewater, glass wastewater, and polar solvent wastewater such as aldehyde and THF. It is also unclear whether it can be processed.

Moreover, in Patent Document 2, considering that the method is a pretreatment method for wastewater treatment, the organic matter is not completely treated. Since the method of Patent Document 2 uses foam separation, it is sufficient if the foam can be generated efficiently, but it is also possible that the generation of foam is not confirmed or the organic matter does not move to the foam.

In addition, in Patent Document 3, it is difficult to treat organic matter in wastewater unless suspended matter is removed, and COD cannot be reduced without relying not only on ozone microbubbles and/or ozone nanobubbles but also on a coagulant. is a matter of concern. In Patent Document 4, since the object is only organic microsolid substances with a high molecular weight (molecular weight of 10,000 or more), it is unknown whether the above-mentioned hard-to-decompose substances such as acrylic and glass can be decomposed. and that the activated carbon used as a catalyst is backwashed with water (excluding water containing microbubbles and/or nanobubbles), which shortens the life of the activated carbon. Even if it were possible to react organic substances other than organic fine solid substances with ozone in the presence of an activated carbon catalyst, adsorption would take precedence unless the COD value was low (40 to 100 mg/L). Catalytic reaction could not occur.

In addition, Patent Documents 2 to 4 describe that it is possible to treat all organic substances, but when the techniques described in these documents are combined, even if it is possible to remove organic fine solid substances, Is it possible to treat persistent substances such as acrylic wastewater, glass wastewater, polar solvent wastewater such as aldehyde and THF, and nitrogen fixed substances such as ammonium sulfate, ammonia, nitrite, or nitrate nitrogen? is unknown.

Therefore, ozone microbubbles and/or ozone nanobubbles, which enable the treatment of persistent organic matter and nitrogen fixed substances such as ammonium sulfate, ammoniacal, nitrite, or nitrate nitrogen, and which do not incur running costs. A final wastewater treatment apparatus for high-concentration persistent organic matter, a system using the apparatus, and a final wastewater treatment method for high-concentration persistent organic matter are disclosed, for example, in Japanese Patent No. 6635444 (Patent Document 5). .

The device and system described in Patent Document 5 are roughly composed of an ozone decomposition reaction device and an ozone catalytic reaction device, and the wastewater final treatment method using the device utilizes ozone microbubbles and / or ozone nanobubbles to generate ozone By reacting organic matter with ozone in the decomposition reactor, most of the organic matter is treated, and by using the layered activated carbon layer as a catalytic reaction field, the ozone catalyst reaction device treats it in the ozone decomposition reactor or the activated carbon tower. This is a system that treats persistent organic matter and organic fine solid matter by reacting final residuals and floating matter with ozone, which could not be done.

However, in the apparatus and system described in Patent Document 5, free radicals or ozone gas generated by the collapse of ozone microbubbles and/or ozone nanobubbles, which are important factors in wastewater treatment, easily return to oxygen through an equilibrium reaction. Therefore, dissolved oxygen will be generated, and if the activated carbon layer is contaminated, the backwashing (cleaning) process must be considered frequently, and the running cost will be incurred to maintain the activated carbon layer. I had concerns.

Here, in view of the above circumstances, the present invention provides the treatment of persistent organic matter, nitrogen fixed matter such as ammonium sulfate, ammonia, nitrite, or nitrate nitrogen, and treatment of organic fine solid matter. and a system using ozone microbubbles and/or ozone nanobubbles for wastewater treatment of high-concentration persistent organic matter and high-concentration persistence To provide a final treatment method for waste water of organic matter.

An object of the final wastewater treatment apparatus according to the present invention is a final wastewater treatment apparatus comprising an ozone generator, an ozone decomposition reaction apparatus, an ozone-ultraviolet decomposition reaction apparatus and an ozone catalyst reaction apparatus, comprising: The ozonolysis reactor includes an ozonolysis reaction tank, a raw water inlet, a first microbubble generator, an ejector pump, a first crushing tower in which a punching plate is installed, a first circulation pump, and a first activated carbon tower. The ozone-ultraviolet decomposition reaction device includes an ozone-ultraviolet decomposition reaction tank, an ultraviolet irradiator, a second microbubble generator, a second circulation pump, a second crushing tower having a punching plate installed therein, and a third circulation. Equipped with a pump and a second activated carbon tower, the ozone catalyst reaction device includes an ozone catalyst decomposition tank, a third microbubble generator, a fourth circulation pump, a third crushing tower having a punching plate installed therein, and a fifth circulation Equipped with a pump and a third activated carbon tower, the ozone generator is connected to the ejector pump, the first microbubble generator, the second microbubble generator and the third microbubble generator by an ozone gas supply pipe. The ozone decomposition reaction tank, the ozone-ultraviolet decomposition reaction tank, and the ozone catalyst decomposition tank are connected by an overflow pipe, and the ozone catalyst decomposition tank has a first activated carbon layer and a second activated carbon layer. is provided, and a backwash water outlet is provided. A further object of the final wastewater treatment apparatus according to the present invention is a final wastewater treatment apparatus comprising an ozone generator, an ozone decomposition reaction apparatus and an ozone catalytic reaction apparatus, wherein the ozone decomposition reaction apparatus comprises , an ozone decomposition reaction tank, a raw water inlet, a first microbubble generator, an ejector pump, a first crushing tower having an orifice installed therein, a first circulation pump and a first activated carbon tower, wherein the ozone-ultraviolet decomposition The reactor comprises an ozone-ultraviolet decomposition reactor, an ultraviolet irradiator, a second microbubble generator, a second circulation pump, a second crushing tower having an orifice therein, a third circulation pump, and a second activated carbon tower. The ozone catalytic reactor comprises an ozone catalytic decomposition tank, a third microbubble generator, a fourth circulation pump, a third crushing tower having an orifice therein, a fifth circulation pump, and a third activated carbon tower. , the ozone generator is connected to the ejector pump, the first microbubble generator, the second microbubble generator, and the third microbubble generator by an ozone gas supply pipe; The ozone-ultraviolet decomposition reaction tank and the ozone catalyst decomposition tank are connected by an overflow pipe. This is effectively achieved by being characterized by the fact that the outlet is provided.

In the final wastewater treatment apparatus according to the present invention, the first crushing tower is installed so as to circulate raw wastewater containing ozone microbubbles through a plurality of pipes to and from the ozone decomposition reaction tank. Alternatively, the first activated carbon tower is installed to circulate wastewater raw water containing ozone gas, ozone microbubbles and/or ozone nanobubbles through a plurality of tubes to and from the ozone decomposition reaction tank, or The second crushing tower is installed to circulate the waste water containing ozone microbubbles through a plurality of pipes between the ozone-ultraviolet decomposition reaction tank, or the second activated carbon tower is By being installed to circulate wastewater raw water containing ozone gas, ozone microbubbles and/or ozone nanobubbles through a plurality of pipes to and from the ozone-ultraviolet decomposition reaction tank, or the third crushing tower, Through a plurality of pipes, waste water containing ozone micro bubbles is installed to circulate between the ozone catalyst decomposition tank, or the third activated carbon tower is installed to circulate ozone gas, ozone micro bubbles through a plurality of pipes. By being installed so as to circulate wastewater raw water containing bubbles and/or ozone nanobubbles between the ozone catalyst decomposition tank, or in the first activated carbon tower, the second activated carbon tower and the third activated carbon tower The activated carbon to be filled is granular activated carbon, and the diameter of the activated carbon is 1 to 2 mm, or the activated carbon to be filled in the first activated carbon layer is pellet-type activated carbon having a diameter of 6 to 7 mm, And the activated carbon filled in the third activated carbon layer is pellet-type activated carbon with a diameter of 3 to 4 mm, or by further comprising the ozone decomposition reaction device and the coagulation sedimentation tank. is achieved.

Further, the objective of the final wastewater treatment system according to the present invention is a final wastewater treatment system using the apparatus described above, wherein the final wastewater treatment system comprises an ozone decomposition reaction tank, raw water Ozonolysis using an ozonolysis reaction apparatus comprising an inlet, a first microbubble generator, an ejector pump, a first crushing tower having a punching plate installed therein, a first circulation pump, and a first activated carbon tower. A treatment system, an ozone-ultraviolet decomposition reaction tank for treating the wastewater raw water treated by the ozone decomposition treatment system, an ultraviolet irradiation device, a second microbubble generator, a second crushing tower having a punching plate installed therein, and a third circulation pump. and an ozone-ultraviolet decomposition system for treatment using an ozone-ultraviolet decomposition reactor comprising a second activated carbon tower; Equipped with a catalyst decomposition tank, a third microbubble generator, a fourth circulation pump, a third crushing tower in which a punching plate is installed, a fifth circulation pump and a third activated carbon tower, and a first activated carbon layer and a second activated carbon The ozone-ultraviolet decomposition system comprises an ozone catalytic decomposition system treated by an ozone catalytic reaction device inside which a layer is installed, and in the ozone-ultraviolet decomposition system, the raw wastewater is irradiated with ultraviolet rays for 2 to 12 hours, and the catalytic decomposition. The system is characterized in that the raw waste water is passed through the first activated carbon layer and the second activated carbon layer at a flow rate of 10 to 100 cm/sec. Furthermore, the final wastewater treatment system according to the present invention is a final wastewater treatment system using the apparatus described above, wherein the final wastewater treatment system comprises an ozone decomposition reaction tank for raw wastewater, and a raw water introduction tank. Ozonolysis treatment system for treatment using an ozonolysis reactor comprising a mouth, a first microbubble generator, an ejector pump, a first crushing tower having an orifice installed therein, a first circulation pump, and a first activated carbon tower , the wastewater raw water treated by the ozone decomposition treatment system is subjected to an ozone-ultraviolet decomposition reaction tank, an ultraviolet irradiation device, a second microbubble generator, a second crushing tower having an orifice installed therein, a third circulation pump, and a second an ozone-ultraviolet decomposition system that uses an ozone-ultraviolet decomposition reactor equipped with an activated carbon tower; , a third microbubble generator, a fourth circulation pump, a third crushing tower in which an orifice is installed, a fifth circulation pump and a third activated carbon tower, wherein the first activated carbon layer and the second activated carbon layer are placed inside An ozone catalyst decomposition system is provided for treatment by an installed ozone catalyst reaction device, wherein the ozone-ultraviolet decomposition system irradiates the wastewater raw water with ultraviolet rays for 2 to 12 hours, and the catalyst decomposition system includes: This is effectively achieved by passing raw waste water through the first activated carbon layer and the second activated carbon layer at a flow rate of 10 to 100 cm/sec.

In addition, the final wastewater treatment system according to the present invention is further provided with at least one or more of the ozone decomposition system, the coagulation system, the filtration system, and/or at least the ozone catalyst decomposition system, Alternatively, the activated carbon with which the first activated carbon layer is filled is pellet-type activated carbon with a diameter of 6-7 mm, and the activated carbon with which the second activated carbon layer is filled is pellet-type activated carbon with a diameter of 3-4 mm. is achieved more effectively.

Further, the object of the wastewater final treatment method according to the present invention is a wastewater final treatment method using the above-described wastewater final treatment system, which comprises a step of ozone decomposition treatment, a step of ozone-ultraviolet decomposition treatment, and a step of ozone catalytic decomposition. It can be effectively achieved by irradiating raw wastewater with ultraviolet rays for 2 to 12 hours in the step of ozone-ultraviolet decomposition treatment.

Further, the purpose of the final wastewater treatment method according to the present invention is to provide at least one or more of the ozone decomposition process, the coagulation process, the filtration process, and/or the ozone catalytic decomposition process. , is more effectively achieved.

According to the final wastewater treatment apparatus according to the present invention, the treatment of persistent organic matter or nitrogen fixed substances such as ammonium sulfate, ammonia, nitrite, or nitrate nitrogen, and further, 1,4-dioxane etc. A final wastewater treatment apparatus for high-concentration persistent organic substances using ozone microbubbles and/or ozone nanobubbles, which can treat polar solvents containing ozone microbubbles and/or ozone nanobubbles without incurring running costs, has become possible.

Further, according to the wastewater final treatment system and the wastewater final treatment method using the wastewater final treatment apparatus for high-concentration persistent organic matter according to the present invention, decomposition reaction treatment and ultraviolet irradiation treatment by ozone microbubbles and/or nanobubbles and ozone gas Furthermore, catalytic reaction treatment and ultraviolet rays in which ozone microbubbles and/or nanobubbles and free radicals generated by the crushing of ozone microbubbles are reacted with hard-to-decompose organic substances such as acrylics and organic fine solid substances in the presence of an activated carbon catalyst. By providing irradiation treatment, it has become possible to treat wastewater with a COD of 5000 (-500,000) mg/L or more.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing a final wastewater treatment apparatus for high-concentration persistent organic matter according to the present invention. FIG. 4 is a schematic diagram showing another embodiment of the final wastewater treatment apparatus for high-concentration persistent organic matter according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a system schematic which shows one aspect|mode which concerns on the waste water final treatment system which concerns on this invention.

First, the final wastewater treatment apparatus for high-concentration persistent organic matter according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic diagram showing a final wastewater treatment apparatus for high-concentration persistent organic matter according to the present invention. As shown in FIG. 1, the final wastewater treatment apparatus 1 comprises an ozone generator 2 , an ozone decomposition reactor 3 , an ozone-ultraviolet decomposition reactor 4 and an ozone catalyst reactor 5 . Next, the ozone decomposition reactor 3 includes an ozone decomposition reactor 31, a raw water inlet 32, a first microbubble generator 33, an ejector pump 34, a first crushing tower 35, a first circulation pump 36, and a first activated carbon tower 37. equip. Next, the ozone-ultraviolet decomposition reaction apparatus 4 includes an ozone-ultraviolet decomposition reaction tank 41, an ultraviolet irradiation device 42, a second microbubble generator 43, a second circulation pump 44, a second crushing tower 45, and a third circulation pump 46. and a second activated carbon tower 47. Next, the ozone catalytic reactor 5 comprises an ozone catalytic decomposition tank 51, a third microbubble generator 52, a fourth circulation pump 53, a third crushing tower 54, a fifth circulation pump 55 and a third activated carbon tower 56. A first activated carbon layer 57 and a second activated carbon layer 58 are disposed inside the ozone catalyst decomposition tank 51, and a backwash water outlet 59 is provided. The ozone gas is supplied from the ozone gas generator 2 through the ozone gas supply pipe Ts connected to the ejector pump 34, the first microbubble generator 33, the second microbubble generator 43, and the third microbubble generator 52. be. The supply amount of ozone gas is 150 to 600 g/h (hour). If the supply amount of ozone gas is less than 150 g/h, the raw water is hardly treated, and if it exceeds 600 g/h, the treatment capacity does not change much.

Next, the ozone reaction device 3 will be explained in more detail. In the embodiment shown in FIG. 1, the raw water inlet 32 is provided in the upper part of the ozone decomposition reaction tank 31 in a columnar shape, but the shape is not particularly limited. In addition, since the introduction port 32 should be capable of injecting waste water containing a high concentration of persistent organic matter (hereinafter referred to as "raw water") into the ozone decomposition reaction tank 31, the upper part of the ozone decomposition reaction tank 31 is an open system. and do not need to be provided separately. Next, in the embodiment shown in FIG. 1, the first microbubble generator 33 is provided in the upper part of the ozone decomposition reaction tank 31. However, since it is sufficient that the microbubbles spread evenly throughout the raw water from the outlet, the installation location may be slightly offset from the center of the ozonolysis reactor 31 . Note that the shape and type of the first microbubble generator 33 are not particularly limited as long as the shape can introduce (supply) the ozone gas from the ozone generator 2 . The ozone microbubbles (diameter of about 20 to 200 μm) supplied from the first microbubble generator 33 cause the raw water to be a gas-liquid mixture containing ozone microbubbles (hereinafter referred to as “raw water containing ozone microbubbles”). Become.

As shown in FIG. 1, the first crushing tower 35 circulates the above-described raw water containing ozone microbubbles through pipes Ta, Tb, and Tc in the order of pipes Ta, Tb, and Tc (see arrows). installed to allow In this case, the pipes Ta, Tb, and Tc may be made of any material, such as metal or plastic, as long as the raw water containing microbubbles can be circulated. Moreover, the target of the pipe, such as laminar flow or turbulent flow, is not particularly limited. Here, when the raw water containing ozone microbubbles is circulated between the first crushing tower 35 and the ozone decomposition reaction tank 31, the ejector pump 34 is required. The reason for adopting this configuration is not only the circulation of the ozone microbubble-containing raw water described above, but also the direct introduction of ozone gas from the ozone gas generator 2 into the raw water (hereinafter, to distinguish this raw water from the ozone microbubble-containing raw water). (hereinafter referred to as "raw water with ozone gas introduced"). The purpose of passing the ozone microbubble-containing raw water and the ozone gas-introduced raw water through the first crushing tower 35 is to crush the ozone microbubbles contained in the raw water in the case of the raw water containing ozone microbubbles to create ozone nanobubbles (on the order of 100 to 500 nm). ), and if the raw water is ozone gas-introduced, the gas-liquid (ozone-raw water) mixed water is generated and circulated to make this gas-liquid mixed water the same as the raw water containing ozone microbubbles. . In other words, the purpose is to continuously generate ozone microbubbles and ozone nanobubbles. Although not shown, a punching plate and an orifice (perforated plate) for crushing microbubbles are inserted in the crushing tower. Incidentally, the hole diameter and shape of the punching plate, orifice, etc. are not particularly limited as long as the microbubbles can be crushed.

Next, like the first crushing tower 35, the first activated carbon tower 37, as shown in FIG. is installed so as to circulate the gas-liquid mixed raw water in the order of pipe Td, pipe Te, and pipe Tf (see arrows). The pipes Td, Te, and Tf in this case are also made of any material, such as metal or plastic, as long as the raw water can be circulated. In addition, the pipe is not particularly limited to laminar flow, turbulent flow, or the like. Here, when circulating the raw water containing microbubbles between the first activated carbon tower 37 and the ozone decomposition reaction tank 31, the first circulation pump 36 is required. Regarding the first circulation pump 36, if the pump is capable of circulating waste water (raw water, etc.) between the activated carbon tower 37 and the ozone decomposition reaction tank 31 at a circulation rate of 100 to 200 L/min, the type etc. is not particularly limited. The amount of circulation by the ejector pump 34 when the raw water containing microbubbles is circulated between the first crushing tower 35 and the ozone decomposition reaction tank 31 is also 100 to 200 L/min. The reason and effect of adopting a circulation rate of 100 to 200 L/min will be described later.

The purpose of the first activated carbon tower 37 is to remove compounds by reaction between organic matter and ozone in the raw water and to remove microorganisms in the raw water. Granular activated carbon with a diameter of 1 to 2 mm is desirable as the activated carbon packed in the tower. If the diameter of the activated carbon is less than 1 mm, these compounds and microorganisms cannot be removed, and if the diameter of the activated carbon is greater than 2 mm, the raw water cannot be circulated and the column may become clogged. In addition, as for the filling of the activated carbon, 70 to 80% of the volume of the first activated carbon tower 37 may be filled.

By pretreating the raw water in the ozone reactor 3 configured as described above, most of the organic matter is treated, and the COD and TOC values of the raw water are reduced to about 1/2 to 1/5. .

Next, the ozone-ultraviolet decomposition reaction device 4 will be described in more detail. First, in the embodiment shown in FIG. 1, the overflow pipe To is shown as connecting (connecting) the upper portion of the ozone decomposition reaction tank 31 and the upper portion of the ozone-ultraviolet decomposition reaction tank 41. Since it is sufficient to introduce the raw water pretreated by the ozone decomposition reactor 3 (hereinafter referred to as "pretreated raw water") into the ozone-ultraviolet decomposition reaction tank 41, there are no particular restrictions on the piping method or installation location. Next, the second microbubble generator 43 is provided above the ozone-ultraviolet decomposition reaction tank 41 in the embodiment shown in FIG. , the installation location may be slightly shifted from the center of the ozone-ultraviolet decomposition reaction tank 41 . The shape and type of the second microbubble generator 43 are not particularly limited as long as the shape can introduce (supply) the ozone gas from the ozone generator 2 . The ozone microbubbles (diameter of about 20 to 200 μm) supplied from the second microbubble generator 43 turn the pretreated raw water into a gas-liquid mixture containing ozone microbubbles. Incidentally, the second microbubble generator 43 may be the same as the first microbubble generator 33 .

The ultraviolet irradiator 42 is provided above the ozone-ultraviolet decomposition reaction tank 41 in the embodiment shown in FIG. However, since the ultraviolet irradiator 42 only needs to be able to irradiate the pretreated raw water in the ozone-ultraviolet decomposition reaction tank 41, it is provided not in the upper part of the decomposition reaction tank 41 but in the middle or lower part thereof, or it can be irradiated from the outside. can be By the way, the purpose of providing the ultraviolet ray irradiator 42 is to minimize the conversion of ozone into oxygen molecules when some of the ozone microbubbles in the raw water remain as microbubbles without being crushed. The purpose is to generate active oxygen species and hydroxyl (hydroxyl group) radicals from ozone by irradiating ultraviolet rays at . Furthermore, the purpose of providing the ultraviolet ray irradiator 42 is to irradiate suspended matter and organic matter by irradiating with ultraviolet rays when the activated carbon layer, which will be described later, does not fulfill the function as a catalytic reaction field or when it is desired to rest the function. The purpose is to promote the reaction with fine solid substances. Incidentally, reactive oxygen species are known to have the same function as free radicals generated when ozone microbubbles and/or ozone nanobubbles are forcibly collapsed, and by oxidizing substances other than ozone and oxygen, , play a role in processing organic matter. Also, the wavelength of the ultraviolet irradiation when treating the organic matter is not particularly limited as long as it is in the ultraviolet region (approximately 100 to 380 nm). It should be noted that the irradiation by the ultraviolet ray irradiator 42 is preferably performed while the raw water is being treated. Moreover, the irradiation time using the ultraviolet ray irradiator 42 is preferably 2 to 12 hours. If the irradiation time is less than 2 hours, the COD and TOC values do not change to the same extent as the raw water COD and TOC values, and even if the irradiation time is 12 hours or more, the efficiency does not increase so much. At this time, the pH of the raw wastewater or pretreated raw water is desirably in a neutral range of about 6.5 to 7.9. Although the decomposition reaction by ultraviolet irradiation is possible even in the weakly basic region of pH 8-9 and the weakly acidic region of around pH 5, the efficiency is lower than in the neutral state. The reason for this is the reactivity of ozone gas and hydroxyl radicals.

Next, the second crushing tower 45, as shown in FIG. It is installed so as to circulate in the order of Tc' (see arrow). In this case, the material of the pipe, such as metal or plastic, does not matter as long as it can circulate the pretreated raw water containing microbubbles. Moreover, the target of the pipe, such as laminar flow or turbulent flow, is not particularly limited. Here, when circulating the raw water containing microbubbles between the second crushing tower 45 and the ozone-ultraviolet decomposition reaction tank 41, the second circulation pump 44 is required. The purpose of passing the pretreated raw water containing microbubbles through the second crushing tower 45 is to crush the ozone microbubbles contained in the raw water into ozone nanobubbles (order of 100 to 500 nm). In other words, the purpose is to continuously generate ozone microbubbles and ozone nanobubbles. Although not shown, like the first crushing tower 35, the second crushing tower 45 has a punching plate or an orifice (perforated plate) inserted therein for crushing microbubbles. Incidentally, the hole diameter and shape of the punching plate, orifice, etc. are not particularly limited as long as the microbubbles can be crushed and used in the method described later.

Similarly to the second crushing tower 45, the second activated carbon tower 47 also receives the above-mentioned pretreated raw water containing ozone microbubbles through pipes Td', Te', and Tf', as shown in FIG. Td', tube Te', and tube Tf' are installed so as to circulate in this order (see arrows). In this case, the pipe may be made of any material, such as metal or plastic, as long as it can circulate the pretreated raw water containing ozone microbubbles (and/or ozone nanobubbles). Moreover, the target of the pipe, such as laminar flow or turbulent flow, is not particularly limited. Here, when circulating the pretreated raw water containing ozone microbubbles (and/or ozone nanobubbles) between the second activated carbon tower 47 and the ozone-ultraviolet decomposition reaction tank 41, the third circulation pump 46 is required. . The third circulation pump 46 is capable of circulating waste water (raw water, etc.) between the second activated carbon tower 47 and the ozone-ultraviolet decomposition reaction tank 41 at a circulation rate of 100 to 200 L/min. If so, there are no particular restrictions on the type. The amount of circulation by the third circulation pump 46 when the raw water containing microbubbles is circulated between the second crushing tower 45 and the ozone-ultraviolet decomposition reaction tank 41 is also 100 to 200 L/min. . The reason and effect of adopting a circulation rate of 100 to 200 L/min will be described later.

Similar to the first activated carbon tower 37, the purpose of the second activated carbon tower 47 is to remove compounds and microorganisms in the raw water by reaction between organic matter and ozone in the raw water. Granular activated carbon with a diameter of 1 to 2 mm is desirable as the activated carbon packed in the tower. If the diameter of the activated carbon is less than 1 mm, these compounds and microorganisms cannot be removed, and if the diameter of the activated carbon is greater than 2 mm, the raw water cannot be circulated and the column may become clogged. As for filling with activated carbon, 70 to 80% of the volume of the second activated carbon tower 47 may be filled in the same manner as the first activated carbon tower 37 .

Next, the ozone catalytic reaction device 5 will be explained in more detail. First, in the embodiment shown in FIG. 1, the overflow pipe To' is shown as connecting (coupling) the upper portion of the ozone-ultraviolet decomposition reaction tank 41 and the upper portion of the ozone catalytic decomposition tank 51. , the raw water secondarily pretreated by the ozone-ultraviolet decomposition reaction device 4 (hereinafter referred to as "secondary pretreated raw water") can be introduced into the ozone catalyst decomposition tank 51, so the piping method, installation location, etc. is not particularly limited. Next, the third microbubble generator 52 is provided above the ozone catalyst decomposition tank 51 in the embodiment shown in FIG. As for the location, it may be slightly shifted from the center of the ozone catalyst decomposition tank 51 . The shape and type of the third microbubble generator 52 are not particularly limited as long as the shape can introduce (supply) the ozone gas from the ozone generator 2 . Ozone microbubbles (about 20 to 200 μm in diameter) supplied from the third microbubble generator 52 make the secondary pretreated raw water a gas-liquid mixture containing ozone microbubbles. Incidentally, the third microbubble generator 52 may be the same as the first microbubble generator 33 and the second microbubble generator 43 .

Next, as shown in FIG. 1, the third crushing tower 54 passes the microbubble-containing secondary pretreated raw water described above through pipe Ta'', pipe Tb'', and pipe Tc'' to pipe Ta'. ', tube Tb'' and tube Tc'' (see arrows). In this case, the material of the pipe, such as metal or plastic, does not matter as long as it can circulate the pretreated raw water containing microbubbles. Moreover, the target of the pipe, such as laminar flow or turbulent flow, is not particularly limited. Here, when circulating the raw water containing microbubbles between the third crushing tower 54 and the ozone catalyst decomposition tank 51, the fourth circulation pump 53 is required. The purpose of passing the secondary pretreated raw water containing microbubbles through the third crushing tower 54 is to crush the ozone microbubbles contained in the raw water into ozone nanobubbles (order of 100 to 500 nm). do. In other words, the purpose is to continuously generate ozone microbubbles and ozone nanobubbles. Although not shown, a punching plate or an orifice (perforated plate) for crushing microbubbles is inserted in the third crushing tower 54 in the same way as the first crushing tower 35 and the second crushing tower 45 . Incidentally, the hole diameter and shape of the punching plate, orifice, etc. are not particularly limited as long as the microbubbles can be crushed and used in the method described later.

Next, similarly to the third crushing tower 54, the third activated carbon tower 56, as shown in FIG. It is installed so as to circulate raw water in the order of pipe Td'', pipe Te'', and pipe Tf'' (see arrows). In this case, the tube may be made of any material, such as metal or plastic, as long as it can circulate the secondary pretreated raw water containing ozone microbubbles (and/or ozone nanobubbles). Moreover, the target of the pipe, such as laminar flow or turbulent flow, is not particularly limited. Here, when circulating the secondary pretreatment raw water containing ozone microbubbles (and/or ozone nanobubbles) between the third activated carbon tower 56 and the ozone catalyst decomposition tank 51, the fifth circulation pump 55 is required. Become. Regarding the fifth circulation pump 55, if it is a pump capable of circulating waste water (raw water, etc.) between the third activated carbon tower 56 and the ozone catalyst decomposition tank 51 at a circulation rate of 100 to 200 L/min. , there are no particular restrictions on the type, etc. The circulation rate of the fifth circulation pump 55 when circulating the microbubble-containing raw water between the third crushing tower 54 and the ozone catalyst decomposition tank 51 is also 100 to 200 L/min. The reason and effect of adopting a circulation rate of 100 to 200 L/min will be described later.

Similar to the first activated carbon tower 37 and the second activated carbon tower 47, the purpose of the third activated carbon tower 56 is to remove compounds by reaction between organic substances in the raw water and ozone and to remove microorganisms in the raw water. is. Granular activated carbon with a diameter of 1 to 2 mm is desirable as the activated carbon packed in the tower. If the diameter of the activated carbon is less than 1 mm, these compounds and microorganisms cannot be removed, and if the diameter of the activated carbon is greater than 2 mm, the raw water cannot be circulated and the column may become clogged. As for filling with activated carbon, 70% or 80% of the volume of the third activated carbon tower 56 may be filled in the same manner as the first activated carbon tower 37 and the second activated carbon tower 47 .

Next, the first activated carbon layer 57, the second activated carbon layer 58, and the backwash water outlet 59 in the ozone catalytic reactor 5 will be described in order.

However, regarding organic matter and harmful microorganisms contained in raw water, pretreated raw water, and secondary raw water, ozone gas, ozone microbubbles and / or ozone nanobubbles, the first activated carbon tower 37, the second activated carbon tower 47, and Most of it is treated (removed or rendered harmless) in the third activated carbon tower 56 . However, when treating wastewater containing a high concentration of persistent organic matter, etc., as in the present invention, some of the high molecular weight (molecular weight of 10,000 or more) organic micro solid matter, persistent organic matter and nitrogen Most of the fixed substances (ammonia state, nitrite state nitrogen, etc.) (hereinafter referred to as "final residue") and organic solvents (polar solvents including 1,4-dioxane, etc.) are removed using ozone gas. , ozone microbubbles and/or ozone nanobubbles and first activated carbon column 37, second activated carbon column 47, and third activated carbon column 56 alone will not work. Here, the first activated carbon layer 57 and the second activated carbon layer 58 are one of important components in the device, system and treatment method according to the present invention. Generally, the role of activated carbon is known to be a deodorizing agent, an adsorbent, a catalyst, etc., utilizing the surface area of pores. However, in the conventional method, when used as a catalyst, the concentration of the reaction substrate must be considerably low (for example, about 40 to 100 mg / L of COD in waste water), otherwise the adsorption will prevail over the catalytic reaction. In the field of wastewater (water purification) treatment, the majority of the role was exclusively as an adsorbent.

Here, in the apparatus according to the present invention, the roles of the first activated carbon layer 57 and the second activated carbon layer 58 are to act as hydroxyl (hydroxyl group) radicals generated from ozone nanobubbles, ozone gas itself, and the like, and final residues contained in the pretreated raw water. of the reaction field, the role of the so-called catalyst. Incidentally, pretreated raw water can be treated even if the COD is 5000 mg/L or more (up to about 150000 mg/L).

First, the first activated carbon layer 57 and the second activated carbon layer 58 will be described. Pellet-type activated carbon is used for the first activated carbon layer 57, and the diameter (effective diameter) of the activated carbon is 6 to 7 mm. This set range is set to be larger (longer) than the second activated carbon layer 58 . On the other hand, pellet type activated carbon is used for the second activated carbon layer 58, and the diameter (effective diameter) of the activated carbon is 3 to 4 mm. This set range is set so that the diameter (effective diameter) is smaller (shorter) than the first activated carbon layer 58 . The reason for this is that when the catalytic reaction in the first activated carbon layer 57 cannot be treated well, the second activated carbon layer 58 is used so that the catalytic reaction can be reliably carried out almost quantitatively in the second activated carbon layer 58, which has a larger specific surface area. The diameter of the pellet-type activated carbon with which the layer 58 is filled is made smaller than the diameter of the pellet-type activated carbon with which the first activated carbon layer 57 is filled. In addition, if the diameter of the pellet-type activated carbon is less than 3 mm, the adsorption reaction is superior to the catalyst, and if it is larger than 7 mm, the pretreated raw water cannot pass through each layer at a sufficient speed. may disappear.
Moreover, when the pretreated raw water containing the final residue is passed through the first activated carbon layer 57 and the second activated carbon layer 58, it is desirable to pass through each layer at a flow rate of 10 to 100 cm/sec. If the flow velocity is less than 10 cm/sec, the adsorption reaction will prevail over the catalyst, and if the flow velocity is higher than 100 cm/sec, neither adsorption nor catalytic reaction will take place. Note that the flow rate may be adjusted by the circulation amount of the fourth circulation pump 53 or the fifth circulation pump 55, or any flow rate adjustment means may be used.

Next, the backwash water outlet 59 will be described. The purpose of using the backwash water outlet 59 is to backwash the pellet-type activated carbon associated with the first activated carbon layer 57 and the second activated carbon layer 58 with ozone microbubble-containing water and/or ozone nanobubble-containing water. . As a backwashing method, ozone microbubble-containing water and/or ozone nanobubble-containing water that has been prepared in advance is stored in an arbitrary container (not shown), and backwashed through a pump P. Backwashing is performed by blowing out the contained water from the water outlet 59 .

As for the number of times of backwashing, there is no particular limitation on the number of times of backwashing or the time of backwashing, as long as biweekly or once a month is the minimum. Incidentally, by backwashing the pellet-type activated carbon related to the first activated carbon layer 57 and the second activated carbon layer 58 with the water containing ozone microbubbles and/or the water containing ozone nanobubbles, compared to backwashing with water (tap water), The life of pellet type activated carbon is extended by about 8 to 20 times. Batch processing is desirable for backwashing.

The embodiment of the wastewater final treatment apparatus for high-concentration persistent organic matter using ozone microbubbles according to the present invention has been described above with reference to FIG. Another embodiment of the waste water final treatment device will be described. In addition, about the code|symbol, it is the same about the part which FIG. 1 overlaps. In this description, the description of the portion overlapping with the aspect shown in FIG. 1 is omitted.

FIG. 2 is a schematic diagram showing another embodiment of the final wastewater treatment apparatus for high-concentration persistent organic matter using ozone microbubbles according to the present invention. In other words, the embodiment shown in FIG. 2 is such that the apparatus shown in FIG. 1 is further equipped with another ozonolysis reactor and a coagulating sedimentation tank in order to carry out further pretreatment.

In this alternative embodiment, the waste water treatment apparatus 1' further comprises an ozone decomposition reactor 3' and a coagulating sedimentation tank 50 in addition to the ozone generator 2, the ozone decomposition reactor 3 and the ozone catalytic reactor 4.

The ozone decomposition reactor 3' has basically the same structure as the ozone decomposition reactor 3, and includes an ozone decomposition reactor 31', a raw water inlet 32', a first microbubble generator 33', an ejector pump 34', It comprises a first crushing tower 35', a first circulation pump 36' and a first activated carbon tower 37'. Since the ozone decomposition reactor 3' is basically the same as the ozone decomposition reactor 3, the role of each component is also omitted.

Next, the coagulating sedimentation tank 50 will be described. In the coagulation sedimentation tank 50, a sedimentation flocculating agent is added to the raw water that has not been pretreated by the ozone decomposition reactor 3' to reduce the COD, and also to remove the organic fine solid substances contained in the raw water as sediments. The purpose is to treat the organic substances that could not be pretreated by the ozonolysis reactor 3'. When coagulating sedimentation is performed, an inorganic coagulating sedimentation agent is added to the raw water introduced into the coagulating sedimentation tank 50 . As for the inorganic flocculant, polyaluminum chloride or aluminum sulfate can be used, and a polymer flocculant can also be used as an auxiliary agent.

The sedimentation and the supernatant (raw water) are separated in the coagulating sedimentation tank 50. The supernatant raw water is passed through an appropriately connected introduction pipe (not shown) to the ozone decomposition reaction tank 31 of the ozone decomposition reaction apparatus 3. ′. On the other hand, the sediment can be compressed and dried by any method and either disposed of or the sediment can be reused as sludge. Then, the supernatant (raw water) is sequentially treated in the ozone decomposition reactor 3, the ozone-ultraviolet decomposition reactor 4, and the ozone catalyst reactor 5.

Although the final wastewater treatment apparatus according to the present invention has been described above, for example, the final wastewater treatment apparatus shown in FIG. The final wastewater treatment system according to the present invention is possible by introducing the above, means or equipment. Further, even if any process, means or device is inserted between the ozone decomposition reaction device 3, the ozone-ultraviolet decomposition reaction device 4 and the ozone catalytic reaction device 5 shown in FIG. It is possible. BEST MODE FOR CARRYING OUT THE INVENTION The final wastewater treatment system and wastewater treatment method according to the present invention will be described below with reference to the drawings. Moreover, it demonstrates, using FIG. 1 or FIG. 2 as needed.

FIG. 3 is a system schematic diagram showing one aspect of the final wastewater treatment system according to the present invention. In the embodiment shown in FIG. 3, first, raw waste water (hereinafter simply referred to as "raw water") is diluted. As for dilution, it is sufficient to dilute with water about 2 to 12 times. If it is less than 2 times, various components contained in the waste water may deteriorate the device or system. Even if it is diluted by 12 times or more, the effect does not change so much.

Next, the diluted raw water is treated by the ozone decomposition treatment system S10. In the case of the present invention, the ozone decomposition treatment system S10 uses the ozone decomposition reactor 3 shown in FIG. 1 or 2 to perform decomposition treatment with ozone microbubbles and ozone microbubble crushing treatment, that is, decomposition treatment with ozone nanobubbles. 1, that is, the raw water containing ozone microbubbles is crushed by the crushing tower with the ejector pump and the circulation pump, and part of the ozone nanobubbles are converted into micro and nanobubbles by crushing the ozone microbubbles. Since the raw water is treated and the ozone gas is directly blown from the ejector pump, the raw water becomes a gas-liquid mixture containing ozone gas. That is, as an image, roughly part of organic matter is oxidatively decomposed by ozone gas, and fine part of organic matter is oxidatively decomposed by ozone microbubbles and/or ozone nanobubbles. Ultimately, most of the organic matter is oxidized. Therefore, when the ozone decomposition treatment system S10 is finished, the COD and TOC values are about 1/2 to 1/5 of the raw water.

Incidentally, in the ozone decomposition system S10, the supply amount of ozone gas is desirably 150 to 600 g/h (hour). If the supply amount of ozone gas is less than 150 g/h, the raw water is hardly treated, and if it exceeds 600 g/h, the treatment capacity does not change much. In addition, in the ozone decomposition system S10, the circulation rate of the raw water in the ozone decomposition reactor 3 is 100 to 200 L/min. If the circulation rate is less than 100 L/min, the destruction of ozone microbubbles and the introduction of ozone gas into the raw water will not be successful, and the raw water will not be sufficiently treated. Or, on the contrary, it causes a decrease in processing capacity. It is desirable that the treatment in the ozone decomposition treatment system S10 takes about 2 to 72 hours. If the treatment time is less than 2 hours, the treatment is not sufficiently performed, and if it is more than 72 hours, the treatment is sufficient, but the failure of the apparatus may be hastened, and depending on the organic matter, the equilibrium reaction may proceed and the original It is possible to return to matter.

Next, in the ozone decomposition treatment system S10, the ozone decomposition treatment using ozone microbubbles, ozone nanobubbles and ozone gas is performed, and then the aggregation treatment system S11 is performed. The coagulation treatment system S11 is a treatment performed in the coagulation sedimentation tank 50 in the schematic diagram shown in FIG. The flocculation treatment performed here is to add a precipitating flocculating agent to the raw water that could not be pretreated as described above to lower the COD, and to The purpose is to treat organic matter that could not be pretreated. When coagulating sedimentation is performed, an inorganic coagulating sedimentation agent is added to the raw water introduced into the coagulating sedimentation tank 50 . As the inorganic coagulating sedimentation agent referred to here, an aluminum-based or iron-based agent can be used, and aluminum sulfate (aluminum sulfate) and PAC (polyaluminum chloride) are particularly suitable. Further, it is possible to use a polymer-based coagulating-sedimenting agent as an auxiliary agent for the inorganic coagulating-sedimenting agent. By the way, although the aggregation treatment system S11 is not necessarily an essential requirement, it is recommended to provide the aggregation treatment system S11 when it is desired to treat the organic fine solid matter more efficiently and completely. In addition, the sediment generated in the aggregation treatment system S11 can be used as sludge, and the sludge can be used as building materials, fertilizer, and the like.

In the ozone decomposition treatment system S10, if the pH (hydrogen ion concentration) of the raw water is about 8.5±1.5, the coagulant may be added without considering pH control. If the pH is outside the range of 8.5±1.5, the pH of the raw water may be controlled by any method so that it falls within the range.

In the coagulation treatment system S11, the ozone decomposition reaction device, the ozone-ultraviolet decomposition reaction device and/or the ozone catalyst reaction device may be connected to the coagulation sedimentation tank, or the coagulation sedimentation tank may be provided independently for treatment. But I don't mind.

Next, after the flocculation system S11, the filtration system S12 is performed. This sand filtration treatment system S12 is for removing by sand filtration the sediment that has not been completely removed by coagulation and sedimentation. Sand is used as a filter medium as in the case of sand filtration, and the grain size of the sand is preferably around 50 μm.

Even if the filtration system S12 is connected to the ozone decomposition reaction device, the ozone-ultraviolet decomposition reaction device and/or the ozone catalyst reaction device through a conduit or the like, the filtration treatment system S12 is independently provided with a sand filtration treatment device or means for treatment. It doesn't matter which one.

Next, the raw water treated by the filtration treatment system S12 (hereinafter referred to as "pretreated raw water") is introduced into the ozone-ultraviolet decomposition reaction system S13 and treated. In the case of the present invention, the ozone-ultraviolet decomposition reaction apparatus 4 shown in FIG. 1 or 2 is used to perform the decomposition treatment with ozone microbubbles and the collapse treatment with ozone microbubbles, that is, the decomposition treatment with ozone nanobubbles and ultraviolet irradiation. 1, that is, the pretreated raw water containing the ozone microbubbles is crushed by the crushing tower, and a part of the pretreated raw water is subjected to the crushing of the ozone microbubbles by the second and third circulating pumps. and undergoes microbubble and nanobubble treatment. That is, as an image, the ozone microbubbles and/or the ozone nanobubbles oxidize and decompose even fine portions of the organic matter. Further, the ultraviolet irradiation by the ozone-ultraviolet decomposition reaction system S13 always generates hydroxyl (hydroxyl group) radicals or various active acids, or promotes ozone oxidation, and most organic substances are oxidatively decomposed.

In the ozone-ultraviolet decomposition reaction system S13, as in the ozone decomposition system S10, the purpose of irradiating with ultraviolet rays is to: The purpose is to minimize the formation of oxygen molecules from ozone, that is, to generate active oxygen species from ozone by irradiating ultraviolet rays in the raw water. Furthermore, in the ozone-ultraviolet decomposition reaction system S13, the purpose of irradiating ultraviolet rays is to irradiate ultraviolet rays when the activated carbon layer described later does not fulfill the function as a catalytic reaction field or when the function is to be suspended. The purpose is to promote the reaction with floating matter and organic fine solid substances. Incidentally, reactive oxygen species are known to have the same function as free radicals generated when ozone microbubbles and/or ozone nanobubbles are forcibly collapsed, and by oxidizing substances other than ozone and oxygen, , play a role in processing organic matter. Also, the wavelength of the ultraviolet irradiation when treating the organic matter is not particularly limited as long as it is in the ultraviolet region (approximately 100 to 380 nm). It should be noted that the ultraviolet irradiation in the ozone-ultraviolet decomposition reaction system S13 is preferably performed while the raw water is being treated. Further, the ultraviolet irradiation time in the ozone-ultraviolet decomposition reaction system S13 is desirably 2 to 12 hours. When the irradiation time is less than 2 hours, the COD and TOC values do not change to the same extent as the raw water COD and TOC values, and even if the irradiation time is longer than 12 hours, the efficiency does not increase so much. At this time, the pH of the raw wastewater or pretreated raw water is desirably in a neutral range of about 6.5 to 7.9. Although the decomposition reaction by ultraviolet irradiation is possible even in the weakly basic region of pH 8-9 and the weakly acidic region of around pH 5, the efficiency is lower than in the neutral state. The reason for this is the reactivity of ozone gas and hydroxyl radicals.

Incidentally, also in the ozone-ultraviolet decomposition reaction system S13, the supply amount of ozone gas is desirably 150 to 600 g/h (hour). If the supply amount of ozone gas is less than 150 g/h, the raw water is hardly treated, and if it exceeds 600 g/h, the treatment capacity does not change much. Further, in the ozone-ultraviolet decomposition reaction system S13, the circulation rate of raw water in the ozone decomposition reaction device 3 is 100 to 200 L/min. If the circulation rate is less than 100 L/min, the ozone microbubbles will not be crushed well, and the raw water will not be sufficiently treated. cause a decline. It should be noted that the treatment in the ozone-ultraviolet decomposition reaction system S13 is preferably performed for about 1 to 72 hours. If the treatment time is less than 1 hour, the treatment is not sufficiently performed, and if it is longer than 72 hours, the treatment is sufficient, but the failure of the apparatus may be hastened, and depending on the organic matter, the equilibrium reaction may proceed and the original It is possible to return to matter.

Next, the raw water treated by the ozone-ultraviolet decomposition reaction system S13 (hereinafter referred to as "secondary pretreated raw water") is introduced into the ozone catalytic decomposition system S14 for treatment. In the case of the present invention, the ozone catalytic decomposition system S14 uses the ozone catalytic reactor 4 as shown in FIG. 1 or 2 to perform decomposition by ozone microbubbles and ozone microbubble crushing, that is, decomposition by ozone nanobubbles. conduct. 1, that is, the pretreated raw water containing the ozone microbubbles is crushed by the crushing tower, and a part of the pretreated raw water is crushed by the first and second circulation pumps. and undergoes microbubble and nanobubble treatment. That is, as an image, the ozone microbubbles and/or the ozone nanobubbles oxidize and decompose even fine portions of the organic matter. Ultimately, most of the organic substances (organic fine solid substances and persistent substances) are oxidized. Furthermore, when the ozone catalytic decomposition treatment system S14 is finished, the COD and TOC values are about 1/8 to 1/12 of the raw water.

Incidentally, also in the ozone catalytic decomposition system S14, the supply amount of ozone gas is desirably 150 to 600 g/h (hour). If the supply amount of ozone gas is less than 150 g/h, the raw water is hardly treated, and if it exceeds 600 g/h, the treatment capacity does not change much. Further, in the ozone catalytic decomposition system S5, the circulation rate of the raw water in the ozone decomposition reactor 3 is 100 to 200 L/min. If the circulation rate is less than 100 L/min, the ozone microbubbles will not be crushed well, and the raw water will not be sufficiently treated. cause a decline. It is desirable that the treatment in the ozone catalyst decomposition treatment system S14 is performed for about 1 to 72 hours. If the treatment time is less than 1 hour, the treatment is not sufficiently performed, and if it is longer than 72 hours, the treatment is sufficient, but the failure of the equipment (especially the activated carbon layer) may be accelerated, and depending on the organic matter, the equilibrium reaction may be delayed. It may progress back to the original substance.

In the ozone catalytic decomposition system S14, hydroxyl (hydroxyl group) radicals generated from ozone nanobubbles, ozone gas itself, etc., and pretreatment raw water The important point is that a reaction field, a so-called catalytic reaction, takes place with the final residue contained in the . As described above, pellet-type activated carbon is used for the first activated carbon layer 57, and the diameter (effective diameter) of the activated carbon is 6 to 7 mm. This set range is set to be larger (longer) than the second activated carbon layer 58 . On the other hand, pellet type activated carbon is used for the second activated carbon layer 58, and the diameter (effective diameter) of the activated carbon is 3 to 4 mm. This set range is set so that the diameter (effective diameter) is smaller (shorter) than the first activated carbon layer 57 . The reason for this is that if the catalytic reaction in the first activated carbon layer 57 is not successful, the catalytic reaction in the second activated carbon layer 58, which has a larger specific surface area, is almost quantitatively ensured. The diameter of the pellet-type activated carbon with which the layer 58 is filled is made smaller than the diameter of the pellet-type activated carbon with which the first activated carbon layer 57 is filled. In addition, if the diameter of the pellet-type activated carbon is less than 3 mm, the adsorption reaction is superior to the catalyst, and if it is larger than 7 mm, the pretreated raw water cannot pass through each layer at a sufficient speed. may disappear.

Moreover, when the pretreated raw water containing the final residue is passed through the first activated carbon layer 57 and the second activated carbon layer 58, it is desirable to pass through each layer at a flow rate of 10 to 100 cm/sec. If the flow velocity is less than 10 cm/sec, the adsorption reaction will prevail over the catalyst, and if the flow velocity is higher than 100 cm/sec, neither adsorption nor catalytic reaction will take place. Note that the flow rate may be adjusted by the circulation amount of the fourth circulation pump 53 or the fifth circulation pump 55 shown in FIG. 1, or any flow rate adjustment means may be used.

In addition, backwashing may be performed when the ozone catalytic decomposition system S14 and the ozone catalytic decomposition system S15 described later are used. The purpose of the backwash is to backwash the first activated carbon layer 57 and the second activated carbon layer 58 as described above. Regarding the number of times of backwashing, there is no particular limitation on the number of times of backwashing or the time of backwashing, as long as the minimum is once a week. Incidentally, by backwashing the pellet-type activated carbon related to the first activated carbon layer 57 and the second activated carbon layer 58 with the water containing ozone microbubbles and/or the water containing ozone nanobubbles, compared to backwashing with water (tap water), The life of pellet type activated carbon is extended by about 8 to 20 times. Batch processing is desirable for backwashing.

Next, after the ozone catalytic decomposition system S14, the ozone catalytic decomposition system S15 is performed. The basic operation is the same as that of the ozone catalytic decomposition system S14. However, if the ozone catalytic decomposition system S14 is not installed after the ozone catalytic decomposition system S14, the final concentrations of COD and THF will not be about 1/10 to 1/20 of the raw water. In other words, if the ozone catalytic decomposition treatment system is completed in one stage in this embodiment, the final concentration of COD, aldehydes, THF and other polar solvents will remain at about 1/10 of the raw water. The water that has been treated by the ozone catalytic decomposition system S15 can be reused as water for diluting raw water.

In addition to the embodiment shown in FIG. As long as the ozone catalyst treatment is performed via the ozone-ultraviolet decomposition reaction treatment, the order of filtration treatment, aggregation treatment, etc. may be changed.

As described above, the above system enables the treatment of waste water with a COD of 5000 mg/L or more (up to about 150,000 mg/L) or difficult-to-decompose waste water such as high-concentration acrylic or glass waste. It also enables the treatment of gaseous or liquid persistent substances, polar solvents including 1,4-dioxane and the like. Further, when performing a pretreatment system, a neutralizing agent such as ammonium chloride may be used for polar solvent-based waste water such as aldehyde and THF.

As described above, it is also possible to treat gaseous or liquid persistent substances. Further, when performing a pretreatment system, a neutralizing agent such as ammonium chloride may be used for polar solvent-based waste water containing aldehyde, 1,4-dioxane, or the like. The final wastewater treatment system and final wastewater treatment method according to the present invention are not limited to the embodiments shown in FIGS. Bring the ozone catalyst treatment system, and follow the method of ozone decomposition treatment, followed by ozone-ultraviolet decomposition treatment, followed by ozone catalyst treatment, filtration treatment, flocculation treatment, etc. in order. You can replace it.

In the above, embodiments of the final wastewater treatment apparatus for high-concentration persistent organic matter, the system using the apparatus, and the final wastewater treatment method for high-concentration persistent organic matter using ozone microbubbles according to the present invention have been described. Needless to say, various aspects can be adopted without departing from matters described in the claims, specification, drawings, or the like.

The above-described embodiment will be further described with an example. 1 to 3 according to the content of the embodiment. In Examples 1 to 3 below, ozone gas and ozone microbubble and ozone nanobubble treatments are referred to as "ozone treatment".

[Example 1] Wastewater treatment of non-degradable wastewater containing polar solvent (ozone treatment)
In Example 1, the wastewater treatment of the polar solvent-containing basic hardly decomposable wastewater was carried out as follows. The term "polar solvent" used herein mainly refers to 1,4-dioxane, and the term "polar solvent-containing recalcitrant wastewater" means wastewater containing a polar solvent such as 1,4-dioxane.

First, a polar solvent-containing difficult-to-decompose wastewater with a TOC (total organic carbon) of 1330 mg/L was subjected to ozone treatment for 1 to 4 hours in an ozone decomposition treatment system (ozone decomposition treatment apparatus 3).

Here, Table 1 shows changes in the concentration of 1,4-dioxane contained in the TOC and the polar solvent-containing hardly decomposable wastewater for each treatment time.

First, the TOC decreased as the treatment time of the ozone treatment was lengthened. Next, as for 1,4-dioxane, the concentration decreased as the treatment time of the ozone treatment was lengthened, and when the ozone treatment was performed for 4 hours, the concentration was about 65% of the concentration before the treatment.

[Example 2] Wastewater treatment of non-degradable basic wastewater (coagulation sedimentation treatment)
In Example 2, coagulation-sedimentation treatment was mainly performed for the wastewater treatment of the basic, difficult-to-decompose wastewater.

First, TOC (total organic carbon) = 1330 mg / L polar solvent-containing basic difficult-to-decompose wastewater (pH = 11.7, hereinafter referred to as "basic wastewater".) Ozonolysis treatment system (ozonolysis treatment Ozone treatment was performed for 1 hour in the apparatus 3).

Next, polyaluminum chloride (PAC) is added to the ozone-treated basic wastewater to perform coagulation treatment, and then an alkali adjuster is added to adjust the pH to between 6.8 and 7.2. took control. Incidentally, the pH at the time of PAC addition was 5.3. The TOC after the treatment was 1010 mg/L.

Further, when the PAC addition conditions were the same and the basic waste water was treated with ozone for 3 hours, the TOC was 910 mg/L. However, coagulation sedimentation was less likely to occur than when ozone treatment was performed for 1 hour.

In Example 2, it was found that the TOC of the basic waste water decreased in proportion to the ozonation time regardless of the presence or absence of coagulation sedimentation.

[Example 3] Wastewater treatment of polar solvent-based wastewater containing 1,4-dioxane etc. In Example 3, in order to confirm the performance of the ozone-ultraviolet decomposition system (ozone-ultraviolet decomposition system 4), By the treatment system (ozonolysis treatment device 3), polar solvent-based wastewater containing 1,4-dioxane and the like was previously treated (batch treatment) with a COD of about 2000 mg/L and a TOC of about 850 mg/L. The ultraviolet irradiation in the ozone-ultraviolet decomposition treatment system was performed continuously for 12 hours, and the ozone gas was continuously supplied for 12 hours at about 200 g/h. As a result, both COD and TOC decreased to about 1/3.

In this example, the concentration of the wastewater before ultraviolet irradiation was about 95 mg/L (ppm), but after 8 hours of ultraviolet irradiation, it was 10 ppm or less. was a value close to

From the above, although there is still room for examination such as the circulation amount of ozone gas, ozone microbubbles and ozone nanobubbles, the irradiation time of ultraviolet rays, etc., at least according to the present invention, all kinds of high-concentration organic substances and nitrogen (ammonia It can be used for the final treatment of wastewater containing not only nitric acid) but also polar solvents such as 1,4-dioxane. In addition, not only ozone microbubbles and/or ozone nanobubbles, but also microbubbles and/or nanobubbles such as oxygen and nitrogen may be used. In addition, the sediment produced by coagulation sedimentation can be applied as sludge to fertilizers, materials, and the like.

1 Wastewater Final Treatment Device 2 Ozone Gas Generator 3 Ozone Decomposition Reactor 4 Ozone-Ultraviolet Decomposition Reactor 5 Ozone Catalytic Reactor 31 Ozone Decomposition Reactor 33 First Microbubble Generator 35 First Crush Tower 37 First Activated Carbon Tower 41 Ozone -Ultraviolet decomposition reaction tank 42 Ultraviolet irradiation device 43 Second microbubble generator 45 Second crushing tower 47 Second activated carbon tower 51 Ozone catalyst reaction tank 52 Third microbubble generator 54 Third crushing tower 56 Third activated carbon tower 57 1 activated carbon layer 58 2nd activated carbon layer

Claims (17)

A wastewater final treatment apparatus for high-concentration persistent organic substances comprising an ozone generator, an ozone decomposition reaction apparatus, an ozone-ultraviolet decomposition reaction apparatus, and an ozone catalyst reaction apparatus,
The ozonolysis reactor includes an ozonolysis reaction tank, a raw water inlet, a first microbubble generator, an ejector pump, a first crushing tower in which a punching plate is installed, a first circulation pump, and a first activated carbon tower. death,
The ozone-ultraviolet decomposition reactor includes an ozone-ultraviolet decomposition reactor, an ultraviolet irradiator, a second microbubble generator, a second circulation pump, a second crushing tower having a punching plate installed therein, a third circulation pump, and Equipped with a second activated carbon tower,
The ozone catalyst reaction apparatus comprises an ozone catalyst decomposition tank, a third microbubble generator, a fourth circulation pump, a third crushing tower having a punching plate installed therein, a fifth circulation pump and a third activated carbon tower,
The ozone generator is connected to the ejector pump, the first microbubble generator, the second microbubble generator and the third microbubble generator by an ozone gas supply pipe,
The ozone decomposition reaction tank, the ozone-ultraviolet decomposition reaction tank, and the ozone catalyst decomposition tank are connected by an overflow pipe,
A final treatment of waste water of high-concentration persistent organic matter, characterized in that a first activated carbon layer and a second activated carbon layer are provided inside the ozone catalyst decomposition tank, and a backwash water outlet is provided. Device. A wastewater final treatment apparatus for high-concentration persistent organic matter, comprising an ozone generator, an ozone decomposition reaction apparatus, and an ozone catalyst reaction apparatus,
The ozone decomposition reactor comprises an ozone decomposition reactor, a raw water inlet, a first microbubble generator, an ejector pump, a first crushing tower having an orifice therein, a first circulation pump, and a first activated carbon tower. ,
The ozone-ultraviolet decomposition reactor includes an ozone-ultraviolet decomposition reactor, an ultraviolet irradiator, a second microbubble generator, a second circulation pump, a second crushing tower having an orifice therein, a third circulation pump, and a third 2 equipped with an activated carbon tower,
The ozone catalytic reaction device comprises an ozone catalytic decomposition tank, a third microbubble generator, a fourth circulation pump, a third crushing tower having an orifice therein, a fifth circulation pump and a third activated carbon tower,
The ozone generator is connected to the ejector pump, the first microbubble generator, the second microbubble generator and the third microbubble generator by an ozone gas supply pipe,
The ozone decomposition reaction tank, the ozone-ultraviolet decomposition reaction tank, and the ozone catalyst decomposition tank are connected by an overflow pipe,
A final treatment of waste water of high-concentration persistent organic matter, characterized in that a first activated carbon layer and a second activated carbon layer are provided inside the ozone catalyst decomposition tank, and a backwash water outlet is provided. Device. 3. The apparatus according to claim 1 or 2, wherein the first crushing tower is installed to circulate raw waste water containing ozone microbubbles through a plurality of pipes to and from the ozonolysis reactor. 4. The method according to any one of claims 1 to 3, wherein the first activated carbon tower is installed so as to circulate raw wastewater containing ozone gas, ozone microbubbles and/or ozone nanobubbles through a plurality of pipes to and from the ozone decomposition reaction tank. A device according to any one of the preceding claims. 5. The second crushing tower according to any one of claims 1 to 4, wherein the waste water containing ozone microbubbles is circulated between the ozone-ultraviolet decomposition reaction tank and the second crushing tower through a plurality of pipes. Apparatus as described. 1 to 4, wherein the second activated carbon tower is installed so as to circulate wastewater raw water containing ozone gas, ozone microbubbles and/or ozone nanobubbles through a plurality of pipes to and from the ozone-ultraviolet decomposition reaction tank. 6. Apparatus according to any one of 5. 7. The third crushing tower according to any one of claims 1 to 6, wherein the third crushing tower is installed so as to circulate the waste water containing ozone microbubbles between the ozone catalytic decomposition tank and the ozone catalyst decomposition tank through a plurality of pipes. Device. 8. The third activated carbon tower is installed so as to circulate raw wastewater containing ozone gas, ozone microbubbles and/or ozone nanobubbles through a plurality of pipes to and from the ozone catalytic decomposition tank. A device according to any one of the preceding claims. The activated carbon packed in the first activated carbon tower, the second activated carbon tower and the third activated carbon tower is granular activated carbon, and the activated carbon has a diameter of 1 to 2 mm. The apparatus described in . The activated carbon filled in the first activated carbon layer is pellet type activated carbon with a diameter of 6 to 7 mm, and the activated carbon filled in the third activated carbon layer is pellet type activated carbon with a diameter of 3 to 4 mm. 10. Apparatus according to any one of claims 1-9. 11. Apparatus according to any one of claims 1 to 10, further comprising one more said ozonolysis reactor and a coagulation-sedimentation tank. A wastewater final treatment system using the apparatus according to any one of claims 1 to 11, comprising:
The final wastewater treatment system includes:
Ozonolysis reaction of wastewater raw water equipped with an ozone decomposition reaction tank, a raw water inlet, a first microbubble generator, an ejector pump, a first crushing tower with a punching plate installed inside, a first circulation pump, and a first activated carbon tower Ozonolysis treatment system using equipment to treat,
The raw waste water treated by the ozone decomposition treatment system is treated by an ozone-ultraviolet decomposition reaction tank, an ultraviolet irradiation device, a second microbubble generator, a second crushing tower having a punching plate installed therein, a third circulation pump, and a second microbubble generator. an ozone-ultraviolet decomposition system for treatment using an ozone-ultraviolet decomposition reactor equipped with an activated carbon tower; , a third microbubble generator, a fourth circulation pump, a third crushing tower in which a punching plate is installed, a fifth circulation pump and a third activated carbon tower, and a first activated carbon layer and a second activated carbon layer are provided inside Equipped with an ozone catalytic decomposition system that is processed by an ozone catalytic reactor installed in
In the ozone-ultraviolet decomposition treatment system, the raw wastewater is irradiated with ultraviolet rays for 2 to 12 hours, and in the catalytic decomposition system, the raw wastewater is subjected to the first activated carbon layer and the A final wastewater treatment system for high-concentration persistent organic matter, characterized in that the wastewater is passed through the second activated carbon layer. A wastewater final treatment system using the apparatus according to any one of claims 1 to 11, comprising:
The final wastewater treatment system includes:
An ozonolysis reaction apparatus comprising an ozonolysis reaction tank for wastewater raw water, a raw water inlet, a first microbubble generator, an ejector pump, a first crushing tower having an orifice therein, a first circulation pump, and a first activated carbon tower. Ozonolysis treatment system to process using,
The wastewater raw water treated by the ozone decomposition treatment system is treated by an ozone-ultraviolet decomposition reaction tank, an ultraviolet irradiation device, a second microbubble generator, a second crushing tower having an orifice installed therein, a third circulation pump, and a second activated carbon. an ozone-ultraviolet decomposition system for treatment using an ozone-ultraviolet decomposition reactor equipped with a tower; Equipped with a third microbubble generator, a fourth circulation pump, a third crushing tower in which an orifice is installed, a fifth circulation pump and a third activated carbon tower, and a first activated carbon layer and a second activated carbon layer are installed inside Equipped with an ozone catalytic decomposition system processed by an ozone catalytic reactor that
In the ozone-ultraviolet decomposition treatment system, the raw wastewater is irradiated with ultraviolet rays for 2 to 12 hours, and in the catalytic decomposition system, the raw wastewater is subjected to the first activated carbon layer and the A final wastewater treatment system for high-concentration persistent organic matter, characterized in that the wastewater is passed through the second activated carbon layer. 14. Wastewater final treatment system according to claim 12 or 13, further comprising at least one or more of said ozonolysis treatment system, flocculation treatment system, filtration treatment system and/or at least said ozone catalytic decomposition system. The activated carbon filled in the first activated carbon layer is pellet type activated carbon with a diameter of 6 to 7 mm, and the activated carbon filled in the third activated carbon layer is pellet type activated carbon with a diameter of 3 to 4 mm. 15. Wastewater final treatment system according to any one of 12 to 14. A final wastewater treatment method using the final wastewater treatment system of high-concentration persistent organic matter using ozone microbubbles according to any one of claims 12 to 15,
It comprises a step of ozone decomposition treatment, a step of ozone-ultraviolet decomposition treatment, and a step of ozone catalytic decomposition, and in the step of ozone-ultraviolet decomposition treatment, raw wastewater is irradiated with ultraviolet rays for 2 to 12 hours. A final wastewater treatment method for high-concentration persistent organic matter. 17. The wastewater final treatment method according to claim 16, further comprising at least one or more of the ozone decomposition process, the flocculation process, the filtration process, and/or the ozone catalytic decomposition process.

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