JP2003200183A - Activated carbon biological water treatment device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an activated carbon biological water treatment device directly treating raw city water by a biological activated carbon, exhibiting a treating ability for a long period of time while decomposing a substance adsorbed to an activated carbon fiber and capable of easily removing manganese or the like and enhancing a sanitary value of city water. <P>SOLUTION: The activated carbon fiber 1 molded to a sheet-like shape is fixed to a mesh plate 2 to form a plate-like element 3 and an element module 4 is formed by providing a plurality of elements in parallel at a predetermined interval. This element module 4 is immersed in a water tank 5 and a diffusing pipe 6 is installed below this element module 4. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biological activated carbon water treatment apparatus for treating raw tap water to produce safe tap water as drinking water. The present invention relates to a biological activated carbon water treatment device which exhibits a treatment capacity for a long period of time while decomposing adsorbed substances and can easily remove manganese and the like.

[0002]

2. Description of the Related Art At present, as raw water for water supply in Japan,
The specific gravity of reservoir water such as dams is increasing. In these reservoirs, microalgae such as green algae and cyanobacteria are often proliferated by so-called nutrient salts such as nitrogen and phosphorus contained in inflowing domestic wastewater and agricultural wastewater, and in tap water using the reservoir water as raw water, Due to the offensive odor-causing substances produced by these microalgae, many problems of offensive odor such as mold odor and algae odor have occurred. In addition, since it is suspected that agrochemicals mainly containing herbicides and trace chemical substances contained in factory effluent flowing from farmlands and golf courses around the reservoir are suspected to be contaminated, safety as tap water is also a concern. Furthermore, the organic substances contained in these raw water for tap water produce disinfection by-products such as trihalomethanes, which have been pointed out to be carcinogenic, when general chlorine disinfection is carried out in tap water purification treatment.

As a conventional technique for treating such raw tap water and supplying it as tap water, a granular activated carbon adsorption treatment is separately added to the process of coagulation sedimentation or rapid filtration, or this granular activated carbon adsorption treatment is carried out. Add a process that combines ozone treatment and granular activated carbon adsorption treatment to
The so-called advanced water treatment process is generally used, and there are many records of construction of water purification plants using this method.

When the ozone treatment and the granular activated carbon adsorption treatment are combined after the rapid filtration as described above, the offensive odor-causing substance and the disinfection by-products such as trihalomethane produced by chlorine disinfection at the time of tap water purification treatment are combined by the ozone treatment. The organic matter in the treated water, which is the cause, is reduced in molecular weight, and the organic matter adsorbed on the surface of the activated carbon is decomposed by aerobic microorganisms that live inside the small pores present on the surface of the granular activated carbon in the latter stage. It is said that the removal ability is exhibited for a period longer than the period assumed from the adsorption ability of the activated carbon, and such activated carbon treatment is called biological activated carbon treatment (BAC).

[0005]

However, the treatment of biological activated carbon with granular activated carbon is effective in this way,
There are some technical problems that remain as below.

[0006] That is, since activated carbon is granular, it is packed in a height of about 1.5 to 2.5 m in use.
Although the water to be treated is caused to flow through the granular activated carbon layer in a downward flow at a constant speed, in this process, the filtering action may be superior to the adsorption action which is the original function of the activated carbon. In such a case, the suspended matter remaining in the water to be treated or the oxidized iron content is retained in the upper layer of the granular activated carbon layer, so that the surface of the granular activated carbon in this part is covered with this retained substance. As a result, the adsorbed substances dissolved in the water to be treated, such as organic substances causing off-flavors, substances causing disinfection by-products, trace chemical substances such as pesticides, etc., become difficult to reach the surface of the activated carbon. The overall adsorption efficiency decreases. In addition, since the pressure loss in the activated carbon layer increases due to the accumulation in the upper layer of the detained matter, it is necessary to backwash the treated water from the lower portion of the activated carbon periodically at a frequency of about once every three days. Therefore,
A conventional biological activated carbon treatment device that uses granular activated carbon stacked in layers is used in the case where the raw tap water contains suspended substances, iron oxides, substances such as microalgae that rapidly clog the activated carbon layer, There is a limit that it cannot be applied unless some pretreatment such as coagulation sedimentation or rapid filtration is performed. Furthermore, in addition to these suspensions and iron oxides, if reduced manganese is present in the water to be treated, it will be oxidized by ozone treatment and attached to the surface of the granular activated carbon, blocking small-diameter pores on the surface. As a result, it becomes a factor of lowering the adsorption function as activated carbon as well as the suspension.

Further, granular activated carbon, which has been frequently used in the treatment of biological activated carbon, has a large number of small pores on the surface of the activated carbon, and aerobic microorganisms inhabit and propagate in the small pores, and further, earthworm-like particles that predate this. Since metazoans live and breed, they may leak into the treated water, resulting in a significant decrease in the sanitary value of tap water.

In view of the problems of the above-mentioned conventional biological activated carbon water treatment apparatus, the present invention directly treats raw tap water with biological activated carbon and decomposes substances to be adsorbed on the activated carbon fiber for a long period of time. It is an object of the present invention to provide a biological activated charcoal water treatment device that exhibits the above effects, can easily remove manganese and the like, and can improve the sanitary value of tap water.

[0009]

In order to achieve the above object, the biological activated carbon water treatment device of the first aspect of the present invention is a sheet-shaped activated carbon fiber fixed to a mesh plate to form a plate-shaped element, A plurality of the elements are arranged side by side at a predetermined interval to form an element module, the element module is immersed in a water tank, and an air diffuser is installed under the element module.

In this biological activated carbon water treatment apparatus, sheet-shaped activated carbon fibers are fixed to a mesh plate to form plate-shaped elements, and a plurality of these elements are arranged side by side at predetermined intervals to form an element module. At the same time, since this element module was dipped in a water tank and an air diffuser was installed under this element module, air flow from the air diffuser caused a flow due to the air lift effect between the elements, and the surface of the activated carbon fiber It is possible to promote contact with the water to be treated and to stir the entire water tank, and further to supplement oxygen necessary for the treatment with biological activated carbon.
As a result, tap water containing suspended solids, iron oxides, microalgae, etc. is directly treated with biological activated carbon, and the harmful carbonaceous substances such as organic odorous substances and organic substances caused by disinfection by-products, which are the original of activated carbon, and harmful agricultural chemicals are also removed. It is possible to exert the treatment ability for a long period of time without deteriorating the adsorption ability, and further, while decomposing the substance to be adsorbed on the activated carbon fiber by the action of the aerobic microorganism attached to the activated carbon fiber. Further, even when the water to be treated contains ammonia nitrogen, it is possible to nitrify ammonia by nitrifying bacteria adhering to the activated carbon fiber, and it is possible to reduce chlorine consumption due to ammonia nitrogen, and further, Manganese in the water to be treated is also converted into manganese oxide in a form that can be easily treated by the catalytic oxidation of microorganisms living on the activated carbon fiber, so it can be easily removed by installing a coagulating sedimentation device or a filtration device in the subsequent stage. Is possible.

In order to achieve the same object, in the biological activated carbon water treatment device of the second aspect of the present invention, a sheet-shaped activated carbon fiber is fixed to a mesh plate to form a disc-shaped element,
A plurality of the elements are arranged side by side at a predetermined interval and the centers are connected by a shaft to form an element module, and a part of the element module is immersed in a water tank so as to be rotationally driven about the shaft. Is characterized by.

In this biological activated carbon water treatment apparatus, sheet-shaped activated carbon fibers are fixed to a mesh plate to form disc-shaped elements, and a plurality of these elements are arranged side by side at predetermined intervals and the centers are connected by an axis. The element module is formed by immersing a part of the element module in a water tank and is driven to rotate about an axis. It is possible to efficiently contact with each other, simultaneously stir the water to be treated in the water tank, and simultaneously supplement oxygen from the atmosphere. As a result, tap water containing suspended solids, iron oxides, microalgae, etc. is directly treated with biological activated carbon, and the harmful carbonaceous substances such as organic odorous substances and organic substances caused by disinfection by-products, which are the original of activated carbon, and harmful agricultural chemicals are also removed. It is possible to exert the treatment ability for a long period of time without deteriorating the adsorption ability, and further, while decomposing the substance to be adsorbed on the activated carbon fiber by the action of the aerobic microorganism attached to the activated carbon fiber. Further, even when the water to be treated contains ammonia nitrogen, it is possible to nitrify ammonia by nitrifying bacteria adhering to the activated carbon fiber, and it is possible to reduce chlorine consumption due to ammonia nitrogen, and further, Manganese in the water to be treated is also converted into manganese oxide in a form that can be easily treated by the catalytic oxidation of microorganisms living on the activated carbon fiber, so it can be easily removed by installing a coagulating sedimentation device or a filtration device in the subsequent stage. Is possible.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the biological activated carbon water treatment apparatus of the present invention will be described below with reference to the drawings.

1 to 2 show a first embodiment of the biological activated carbon water treatment apparatus of the present invention. In this biological activated carbon water treatment device, a sheet-shaped activated carbon fiber 1 is fixed to a mesh plate 2 to form a plate-shaped element 3, and a plurality of the elements 3 are arranged in parallel at a predetermined interval. It forms the module 4. In this biological activated carbon water treatment device, the element module 4 is immersed in a water tank 5 into which water to be treated is introduced, and an air diffusing pipe 6 is installed below the element module 4.

The activated carbon fiber 1 can be obtained by subjecting a chemical fiber such as rayon or the like to a high temperature treatment to carbonize it in the presence of steam, to obtain an activated carbon fiber having an adsorption capacity several hundred times that of granular activated carbon. This activated carbon fiber 1 is formed into a sheet and fixed to a net plate 2 made of a corrosion resistant material such as stainless steel or synthetic resin to form a plate-shaped element. The sheet-shaped activated carbon fiber 1 can be arranged on one side or both sides of the mesh plate 2, and can be fixed to the mesh plate 2 by adhesion or a fastener such as a bolt. In addition, in this embodiment, a large number of elements 3 are arranged at regular intervals, and the box-shaped element module 4 is integrally formed by surrounding the elements 3 with side plates 7.

On the other hand, the water tank 5 in which the element module 4 is immersed has an inner enclosure wall 51 which surrounds the periphery of the element module 4 at its upper part, and enhances the air lift effect by the air diffuser 6 together with the side plate 7 of the element module 4. ing. Further, the air diffuser 6 is connected to a blower (not shown) and can aerate the element module 4. In this embodiment, as shown in FIG. 1 (b), a coagulating sedimentation device 9 and a filtration device 10 are provided after the biological activated carbon water treatment device A.

Thus, in the biological activated carbon water treatment apparatus of the first embodiment, the activated carbon fiber 1 formed into a sheet shape is used as the net plate 2.
To form a plate-shaped element 3, and a large number of the elements 3 are juxtaposed at predetermined intervals to form an element module 4, and the element module 4 is immersed in a water tank 5 to form the element module. Since the air diffuser 6 is installed below the air diffuser 6, the air from the air diffuser 6 causes a flow due to the air lift effect between the elements 3 to promote the contact between the surface of the activated carbon fiber 1 and the water to be treated and the water tank. It is possible to carry out stirring of the whole 5 and to supplement oxygen necessary for the treatment of biological activated carbon. As a result, tap water containing suspended solids, oxides of iron, microalgae, etc. is directly treated with bioactive carbon, and the harmful carbonaceous substances such as pesticides and other organic substances caused by the original off-flavor substances of active carbon and disinfection by-products. It is possible to exert the treatment ability for a long period of time without deteriorating the adsorption ability and further decomposing the substance to be adsorbed on the activated carbon fiber 1 by the action of the aerobic microorganisms attached on the activated carbon fiber 1. Further, even when the water to be treated contains ammonia nitrogen, nitrification of ammonia can be carried out by the nitrifying bacteria adhering to the activated carbon fiber 1, and the chlorine consumption due to ammonia nitrogen can be reduced. Since manganese in the water to be treated is also converted into manganese oxide in a form that can be easily treated by catalytic oxidation of microorganisms living on the activated carbon fiber 1, it is easily removed by installing a coagulating sedimentation device or a filtration device in the subsequent stage. It is possible to

Next, a second embodiment of the biological activated carbon water treatment apparatus of the present invention will be described with reference to FIGS. This biological activated carbon water treatment device is a sheet-shaped activated carbon fiber 1
Is fixed to the mesh plate 2 to form a disc-shaped element 3, and a large number of the elements 3 are arranged side by side at predetermined intervals.
The centers of the juxtaposed elements 3 are connected by a shaft 8 to form an element module 4. The biological activated carbon water treatment device supports the shaft 8 so that the lower part of the element module 4 is immersed in the water tank 5 into which the water to be treated is introduced, and the shaft 8 is driven by a driving device (not shown) such as a motor. It is configured so as to be driven to rotate in the center, and the water treatment is performed while rotating the element module 4.

The activated carbon fiber 1 can be obtained by carbonizing a chemical fiber such as rayon by steaming at a high temperature in the presence of steam to obtain an activated carbon fiber 1 having an adsorption capacity several hundred times that of granular activated carbon. This activated carbon fiber 1 is formed into a sheet and fixed to a net plate 2 made of a corrosion resistant material such as stainless steel or synthetic resin to form a plate-shaped element 3. The sheet-shaped activated carbon fiber 1 can be arranged on one side or both sides of the mesh plate 2, and can be fixed to the mesh plate 2 by adhesion or a fastener such as a bolt. In this embodiment, as shown in FIG. 3 (b), the membrane filtration device 11 and the like are provided at the subsequent stage of the biological activated carbon water treatment device A.

Thus, in the biological activated carbon water treatment apparatus of the second embodiment, the activated carbon fiber 1 formed into a sheet is used as the net plate 2.
To form the disk-shaped element 3, a large number of the elements 3 are arranged in parallel at a predetermined interval, and the centers are connected by the shaft 8 to form the element module 4, and a part of the element module 4 is formed. Since it is immersed in the water tank 5 and is driven to rotate about the shaft 8, the activated carbon fiber 1 of the element 3 is rotated by the rotation of the element module 4.
And the water to be treated can be efficiently contacted, and the water to be treated in the water tank 5 can be stirred and oxygen from the atmosphere can be supplied at the same time. As a result, suspended substances and iron oxides,
Raw tap water containing microalgae is directly treated with bioactive carbon, and the ability to adsorb harmful trace chemicals such as natural odorous substances and disinfection by-products originating from activated carbon and harmful chemical substances such as pesticides is not impaired, and activated carbon fiber 1 By the action of the aerobic microorganisms attached to the upper part, it is possible to exert the treatment ability for a long period of time while decomposing the substance to be adsorbed on the activated carbon fiber 1. Further, even when the water to be treated contains ammonia nitrogen, nitrification of ammonia can be carried out by the nitrifying bacteria adhering to the activated carbon fiber 1, and the chlorine consumption due to ammonia nitrogen can be reduced. Since manganese in the water to be treated is also converted into manganese oxide in a form that can be easily treated by catalytic oxidation of microorganisms living on the activated carbon fiber 1, it is easily removed by installing a coagulating sedimentation device or a filtration device in the subsequent stage. It is possible to

Although the embodiment of the biological activated carbon water treatment apparatus of the present invention has been described above, the structure of the present invention is not limited to the description of this embodiment, and may be appropriately modified within the scope of the invention. Is possible.

[0022]

According to the biological activated carbon water treatment apparatus of the first aspect of the present invention, sheet-shaped activated carbon fibers are fixed to a mesh plate to form plate-shaped elements, and a plurality of these elements are arranged at predetermined intervals. Installed to form an element module, dip this element module in a water tank,
Since the air diffuser is installed under this element module, the air from the air diffuser causes a flow due to the air lift effect between the elements, which promotes the contact between the surface of the activated carbon fiber and the water to be treated and the entire water tank. Stirring can be performed, and in addition, supplementation of oxygen required for biological activated carbon treatment can be performed. As a result, suspended solids and iron oxides,
Raw tap water containing microalgae is directly treated with bioactive carbon, and it does not impair the ability to adsorb harmful trace chemical substances such as the original off-flavor substances of the active carbon, disinfection by-products, pesticides, etc. By the action of the aerobic microorganisms attached to the, it is possible to exert the treatment ability for a long period of time while decomposing the substance to be adsorbed on the activated carbon fiber. Further, even when the water to be treated contains ammonia nitrogen, it is possible to nitrify ammonia by nitrifying bacteria adhering to the activated carbon fiber, and it is possible to reduce chlorine consumption due to ammonia nitrogen, and further, Manganese in the water to be treated is also converted into manganese oxide in a form that can be easily treated by the catalytic oxidation of microorganisms living on the activated carbon fiber, so it can be easily removed by installing a coagulating sedimentation device or a filtration device in the subsequent stage. Is possible. Furthermore, the element in which the activated carbon fiber formed in a sheet shape used for the biological activated carbon water treatment device of the present invention is fixed to the mesh plate has almost no small holes on the activated carbon surface like the granular activated carbon conventionally used in biological activated carbon treatment. Because it doesn't exist,
Earthworm-like metazoans that prey on aerobic microorganisms do not leak into the treated water, and the sanitary value of tap water can be improved.

According to the biological activated carbon water treatment apparatus of the second aspect of the present invention, the sheet-shaped activated carbon fiber is fixed to the mesh plate to form a disc-shaped element, and a plurality of these elements are arranged at predetermined intervals. While forming an element module by arranging them side by side and connecting the centers with an axis, by immersing a part of this element module in a water tank so as to drive the rotation about the axis, the rotation of the element module The activated carbon fiber of the element and the water to be treated can be efficiently contacted, and the water to be treated in the water tank can be stirred and oxygen can be supplied from the atmosphere at the same time. As a result, tap water containing suspended solids, iron oxides, microalgae, etc. is directly treated with biological activated carbon, and the harmful carbonaceous substances such as organic odorous substances and organic substances caused by disinfection by-products, which are the original of activated carbon, and harmful agricultural chemicals are also removed. It is possible to exert the treatment ability for a long period of time without deteriorating the adsorption ability, and further, while decomposing the substance to be adsorbed on the activated carbon fiber by the action of the aerobic microorganism attached to the activated carbon fiber. Further, even when the water to be treated contains ammonia nitrogen, it is possible to nitrify ammonia by nitrifying bacteria adhering to the activated carbon fiber, and it is possible to reduce chlorine consumption due to ammonia nitrogen, and further, Manganese in the water to be treated is also converted to manganese oxide in a form that can be easily treated by the catalytic oxidation of microorganisms living on activated carbon fibers, so it can be easily removed by installing a coagulating sedimentation device or a filtration device in the subsequent stage. Is possible. Further, the disk-shaped element used in the biological activated carbon water treatment device of the present invention, in which the activated carbon fiber formed into a sheet is fixed to the mesh plate, is on the surface of the activated carbon like the granular activated carbon conventionally used in the treatment of biological activated carbon. Since there are few small holes, earthworm-like metazoans that prey on aerobic microorganisms do not leak into the treated water, and the sanitary value of tap water can be improved.

[Brief description of drawings]

FIG. 1 shows a first embodiment of a biological activated carbon water treatment apparatus of the present invention, (a) is a cross-sectional view, and (b) is a front view showing an example of a combination of the biological activated carbon water treatment apparatus and another treatment apparatus. is there.

FIG. 2 shows a biological activated carbon water treatment apparatus of the same embodiment,
(A) is a partially broken front view of the element, and (b) is a perspective view of the element module.

FIG. 3 shows a second embodiment of the biological activated carbon water treatment apparatus of the present invention, (a) is a sectional view, and (b) is a front view showing an example of a combination of the biological activated carbon water treatment apparatus and another processing apparatus. is there.

FIG. 4 shows a biological activated carbon water treatment apparatus of the same embodiment,
(A) is a partially broken front view of the element, and (b) is a perspective view of the element module.

[Explanation of symbols]

1 activated carbon fiber 2 mesh plate 3 elements 4 element module 5 aquarium 51 Middle enclosure wall 6 Air diffuser 7 side plate 8 axes 9 Coagulation sedimentation equipment 10 Filtration device 11 Membrane filtration device

Continued front page    F-term (reference) 4D003 AA01 AA09 AB02 EA02 EA16                       EA25                 4D024 AA01 AB04 AB13 AB16 BA02                       BB02 BC01 BC04 CA07 DA06                       DA07 DB15

Claims (2)

[Claims] 1. A sheet-shaped activated carbon fiber is fixed to a mesh plate to form a plate-shaped element, and a plurality of the elements are arranged side by side at a predetermined interval to form an element module. A biological activated carbon water treatment device, characterized in that it is immersed in a water tank and an air diffuser is installed under the element module. 2. An element module is formed by fixing sheet-shaped activated carbon fibers to a mesh plate to form disc-shaped elements, and arranging a plurality of such elements at predetermined intervals and connecting the centers with an axis. At the same time, a part of the element module is immersed in a water tank so that the element module is driven to rotate about the shaft as a center.