JP2003080285A - Water treatment equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide water treatment equipment which can sufficiently enhance cleaning efficiency. SOLUTION: The water treatment equipment 1 is provided with a reaction vessel 5 which stores wastewater 2 containing carriers 3 holding microorganisms. A cylindrical body 13 having an upper surface opening part 11 and a lower surface opening part 12 is arranged in the reaction vessel 5. The rotary vanes 24 of a downward flow generating means 21 to generate downward flow A are arranged in the cylindrical body 13. A screens 31 which is a carrier separation means to separate and remove the carriers 3 from the wastewater 2 flowing out of the inside of the cylindrical body 13 by using the downward flow A and to convert the downward flow A into the slope flow B are arranged at the downward position of the cylindrical body 13. The wastewater which has passed through the screen 31, flows out from the reaction vessel 5 through the inside of a wastewater flowing-out means 41.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water treatment device for purifying waste water by using a carrier holding microorganisms.

[0002]

2. Description of the Related Art Conventionally, water treatment apparatuses of this type of carrier method are disclosed in, for example, JP 2001-29975A and JP 2A.
The structure described in Japanese Patent Publication No. 001-38377 is known.

In this conventional water treatment device, a cylindrical cylindrical body having upper and lower openings and arranged in the reaction tank so that the axial directions thereof coincide with each other in the vertical direction, and a downward flow is generated in the cylindrical body. Downstream generating means is provided, and a cylindrical carrier separating portion is provided in the cylindrical body, and the waste water from which the carrier has been separated and removed by the carrier separating portion is made to flow out of the reaction tank through an outflow pipe. ing.

[0004]

However, in the above-mentioned conventional water treatment apparatus, for example, a swirl circulation flow, which is a part of the downward flow in the cylindrical body, is unlikely to occur in the reaction tank, and the purification treatment efficiency is sufficiently high. There is a problem that it may not be possible to increase the value.

The present invention has been made in view of the above points, and can appropriately generate a swirling circulation flow having a downward flow in the tubular body as a part in the reaction tank, thereby sufficiently improving the purification treatment efficiency. It is an object of the present invention to provide a water treatment device that can be improved.

[0006]

A water treatment apparatus according to claim 1 is a water treatment apparatus for purifying wastewater by using a carrier holding microorganisms, and storing the wastewater containing the carrier holding microorganisms. And a cylindrical body having upper and lower openings having an upper surface opening and a lower surface opening, which are arranged in the reaction tank such that the axial directions thereof coincide with each other in the vertical direction, and a downward flow in the cylindrical body. The descending flow generating means to be generated and the carrier disposed in a position below the cylindrical body are separated and removed from the drainage flowing out from the cylindrical body through the lower surface opening by the descending flow generated by the descending flow generating means. And carrier separating means for converting the downward flow generated by the downward flow generating means into an inclined flow in a direction inclined with respect to the vertical direction.

Then, the carrier is separated and removed from the drainage flowing out from the cylindrical body through the lower surface opening by the downward flow generated by the downward flow generating means, and the downward flow generated by the downward flow generating means is inclined in the vertical direction. Since the carrier separating means for converting into the inclined flow is arranged at the lower position of the cylindrical body, the swirling circulation flow, which is a part of the downward flow in the cylindrical body, is appropriately generated in the reaction tank.

According to a second aspect of the present invention, there is provided the water treatment apparatus according to the first aspect, wherein the carrier separating means is located coaxially with the tubular body and has a cone whose diameter gradually increases from the upper end to the lower end. And a drainage passage portion which is formed in an opening in the body portion and which separates and removes the carrier from the wastewater by prohibiting the passage of the carrier, and through which the wastewater separated and removed by the carrier passes. .

The carrier separating means having the conical main body and the drainage passage formed in the main body has a simple structure, but the swirl is caused by a downward flow in the tubular body. Circulating flow is properly generated in the reaction vessel.

According to a third aspect of the present invention, in the water treatment apparatus according to the first aspect, the carrier separating means is located on the same axis as the cylindrical body and has a pyramidal shape that gradually expands from the upper end to the lower end. And a drainage passage portion which is formed in the body portion and has an opening formed in the body portion to separate and remove the carrier from the wastewater by passing through the wastewater.

The carrier separating means having the pyramid-shaped main body and the drainage passage formed in the main body has a simple structure, but a swirl part of which is the downward flow in the tubular body. Circulating flow is properly generated in the reaction vessel.

According to a fourth aspect of the present invention, there is provided the water treatment apparatus according to the second or third aspect, wherein the drainage passage comprises a plurality of elongated holes having a longitudinal direction in the direction of the inclined flow. Is.

Further, since the drainage passage is composed of a plurality of elongated holes having a longitudinal direction in the direction of the inclined flow, it is possible to prevent entanglement of fibrous substances mixed in the drainage.

According to a fifth aspect of the present invention, there is provided the water treatment apparatus according to any of the first to fourth aspects, wherein the descending flow generating means is driven and rotated in the cylindrical body to descend into the cylindrical body. It has a plurality of rotating blades for generating.

By driving and rotating the plurality of rotary blades in the cylindrical body, it is possible to reliably generate a downward flow in the cylindrical body.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION A configuration of an embodiment of a water treatment apparatus of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a water treatment device, which is a carrier (microorganism immobilization carrier) 3 for holding wastewater 2 such as domestic wastewater, industrial wastewater, landfill leachate, etc.
This is a carrier-type water treatment device for biological purification treatment using. The carrier 3 is composed of, for example, a porous granular material that is insoluble in the wastewater 2 and can float in the wastewater 2, and has microorganisms immobilized on its surface and fine pores.

As shown in FIG. 1, the water treatment device 1 is provided with a reaction tank 5 which is a storage tank for storing the waste water 2 containing a plurality of carriers 3 holding microorganisms. Wastewater 2 to be purified from the inflow pipe 6 which is the wastewater inflow means
And a plurality of carriers 3 are introduced by a predetermined method.

The reaction tank 5 has, for example, a box shape with an open top, that is, a bottomed tubular shape having a horizontal bottom plate portion 8 and a vertical side plate portion 9 rising from the peripheral edge of the bottom plate portion 8 (for example, , A cylindrical shape, or a polygonal tubular shape such as a triangular shape or a triangular shape). The reaction tank 5 is, for example, an anaerobic reaction tank such as a denitrification tank, and the immobilized microorganisms are anaerobic microorganisms such as denitrification bacteria.

Then, in the reaction tank 5, there is formed a cylindrical shape having an upper surface opening 11 and a lower surface opening 12 and having upper and lower openings (for example, a cylindrical shape, or a polygonal cylindrical shape such as a triangle or a square). The formed tubular body 13, which is a rectifying body, is arranged at a substantially central position in the reaction tank 5 with the axial direction of the tubular body 13 aligned with the vertical direction.

The tubular body 13 having the upper and lower openings has a predetermined size corresponding to the capacity of the reaction tank 5 so that the entire tubular body 13 is immersed in the waste water 2 stored in the reaction tank 5. Has become. That is, the upper surface opening 11 that is the inlet of the tubular body 13.
Is located below the water surface of the waste water 2 stored in the reaction tank 5, and the lower surface opening 12 which is the outlet of the tubular body 13 is located above the bottom surface of the reaction tank 5 (the upper surface of the bottom plate portion 8). The entire tubular body 13 is immersed in the drainage 2.

Further, the water treatment device 1 is provided with the downflow generating means 21 for generating the downflow A in the cylindrical body 13.

The descending flow generating means 21 has a drive motor 22 which is a drive source. The drive motor 22 is provided with an upper end portion of a rotary shaft 23 in the vertical direction, and a cylindrical body of the rotary shaft 23.
Rotating blades 24, which are stirring blades such as a plurality of impellers, are radially attached to the lower end located inside 13. The plurality of rotary vanes 24 are rotated by the power from the drive motor 22.
It is driven and rotated in the tubular body 13 together with the 23
It is configured to generate a downward flow A of the drainage 2 in the inside 13. The tubular body 13 and the downward flow generating means 21 constitute a draft tube type stirring means 30.

Further, the water treatment device 1 has a downflow generating means.
The downward flow A from 21 causes the lower surface opening 12 from the inside of the cylindrical body 13.
The carrier 3 is captured and separated and removed from the waste water 2 flowing out through the downward flow A, and the downward flow A generated by the downward flow generating means 21 is inclined at a predetermined angle (30 ° to 60 °, preferably 4 °).
5 °) α and a screen 31 which is a carrier separating means for converting into a linear inclined flow (downward inclined flow) B in the inclined direction.
The screen 31 is disposed below the tubular body 13 and at a lower position in the reaction tank 5, and is placed on the bottom plate portion 8 of the reaction tank 5. That is, the screen 31 is for taking out the wastewater 2 not containing the carrier 3 from the inside of the reaction tank 5, and the liquid discharged or ejected from the inside of the cylindrical body 13 at the lower vicinity of the cylindrical body 13, that is, the bottom of the reaction tank 5. It is arranged at a position where it is exposed to a downward flow A which is a flow.

As shown in FIG. 2, the screen 31 has a conical main body 32 whose diameter gradually increases from the upper end to the lower end, and the main body 32 is positioned coaxially with the tubular body 13. However, the central axis of the main body 32, the central axis of the tubular body 13, and the central axis of rotation of the rotary shaft 23 coincide with each other.

The carrier 3 is separated and removed from the drainage 2 by prohibiting passage of the carrier 3 on the upper end side which is the apex of the body 32, that is, on the upper part of the body 32, and the carrier 3 is separated and removed. A drainage passage portion 33, which is an opening through which the wastewater 2 passes as treated water, is formed. That is, the main body 32
A drainage passage portion 33 is formed only at a portion facing the tubular body 13 and opens upward toward the tubular body 13.

The drainage passage portion 33 is composed of a plurality of radial elongated holes 34 having a longitudinal direction in the direction of the inclined flow B, for example. The plurality of elongated holes 34 are formed in a slit shape having a width smaller than that of the carrier 3, and are arranged over substantially the entire circumference of the main body 32 in a state of being arranged at equal intervals in the circumferential direction of the main body 32. There is. The entire outer peripheral surface (peripheral side surface) of the main body portion 32 other than the elongated hole 34 is a guide surface 35 that is an inclined action surface that converts the downward flow A into the inclined flow B.

Further, the water treatment device 1 is provided with an outflow pipe 41 which is a wastewater outflow means for outflowing the treated water, which is the wastewater 2 from which the carrier 3 has been separated and removed by the screen 31, to the outside of the reaction tank 5. Is a bottom plate portion 8 at a lower position in the reaction tank 5.
Are arranged horizontally along the.

The upstream end, which is one end of the outflow pipe 41, is connected to the main body 32 of the screen 31, and the internal flow path of the outflow pipe 41 is connected.
42 communicates with the internal space 43 of the main body 32. The downstream end, which is the other end of the outflow pipe 41, is open in a tank (reaction tank, precipitation tank, etc.) (not shown) in the next treatment step. Although not shown, a bubble removing means such as a chamber capable of separating and removing bubbles caused by nitrogen gas or the like generated in the reaction tank 5 and having passed through the drainage passage 33 together with the drainage 2 from the treated water is provided in the outflow pipe 41.
It may be provided in the middle of.

Next, the operation of the water treatment device 1 of the above-described embodiment will be described.

When the water treatment device 1 is in operation, the rotary vane 24 is rotated by the power from the drive motor 22 of the downward flow generating means 21.
In combination with the cylinder body 13, the cylinder body 13 is driven and rotated in a predetermined direction, and a downward flow A is generated in the cylinder body 13.

When the downward flow A is generated in the tubular body 13, the wastewater 2 containing the carrier 3 holding the microorganisms flows downward in the tubular body 13 by the downward flow A, that is, in the internal flow path of the tubular body 13. Then, it flows out (jets) from this internal flow path through the lower surface opening 12, and flows downward toward the lower screen 31. The flow velocity of the drainage 2 forming the downward flow A when flowing out of the tubular body 13 is set to a value in the range of 1 m / s to 3 m / s, for example.

The carrier 3 floating in the wastewater 2 is captured and separated and removed by the screen 31, and the wastewater 2 separated and removed from the carrier 3 passes through the wastewater passage portion 33 as treated water and passes through the main body. It enters the internal space 43 of the portion 32, and then flows through the internal flow path 42 of the outflow pipe 41 into the tank (not shown) of the next processing step.

The carrier 3 separated from the drainage 2 once adheres to the periphery of the drainage passage portion 33 of the screen 31, but immediately the inclined flow B (sweeping along the screen surface which is the guide surface 35 of the main body portion 32) is performed. ), And moves along the guide surface 35 of the main body 32. Therefore, the carrier 3 separated from the wastewater 2
Therefore, the slit-shaped long holes 34 are not blocked and clogged, and the carrier 3 is continuously and appropriately separated at the drainage passage portion 33.

On the other hand, the internal space of the main body 32 of the screen 31
The wastewater 2 during treatment that has not entered 43 flows along the inclined main body 32 by the inclined flow B generated by converting the downward flow A by the guiding action of the guide surface 35 of the main body 32, The inclined flow B is converted by the guiding action of the horizontal bottom plate 8 and horizontally flows along the bottom plate 8 by the horizontal flow C generated.

Thereafter, the drainage 2 is discharged from the vertical side plate portion 9
The horizontal flow C is converted by the guiding action of the above and the upward flow D generated around the cylindrical body 13 causes the upward flow to flow upward along the side plate portion 9 and the cylindrical body 13, and then the horizontal flow E generated near the water surface.
Flows into the cylindrical body 13 through the upper surface opening 11.

In this way, the entire reaction vessel 5 has a cylindrical body.
A swirling circulation flow having a downward flow A in 13 as a part, that is, a downward flow A, an inclined flow B, a horizontal flow C, an upward flow D and a horizontal flow E.
A swirl circulation flow consisting of is generated, and by this swirl circulation flow in the entire reaction tank 5, the wastewater 2 and the carrier 3 are circulated while being stirred in the entire reaction tank 5. Therefore, the pollutants of the wastewater 2 and the microorganisms of the carrier 3 (for example, anaerobic microorganisms such as denitrifying bacteria)
And are efficiently brought into contact with each other, and mainly by the biological reaction of the microorganisms, nitrate nitrogen is converted into nitrogen gas, which is a harmless gas, and the wastewater 2 is efficiently purified.

Then, the water treatment apparatus 1 of the above-mentioned one embodiment
According to the downflow A, the lower surface opening from the inside of the cylindrical body 13
A screen that separates and removes the carrier 3 from the wastewater 2 that has flowed through 12 and converts the downward flow A into a tilted flow B.
Since 31 is arranged at the lower position of the tubular body 13, a swirl circulation flow passing through the downward flow A in the tubular body 13 can be appropriately generated in the entire reaction vessel 5, and thus the entire reaction vessel 5 can be produced. Can be reliably stirred, and the purification treatment efficiency can be sufficiently enhanced.

Further, since the carrier 3 separated from the waste water 2 can be washed away by the inclined flow B, the long holes 34 are not clogged and blocked by the captured carrier 3, and the waste water is treated water. 2 can be appropriately flown out of the reaction tank 5 from the outflow pipe 41 through the screen 31, and an efficient purification treatment can be appropriately maintained.

Further, since the drainage passage portion 33 of the screen 31 is constituted by a plurality of slit-shaped elongated holes 34 having a longitudinal direction in the direction of the inclined flow B, for example, a fibrous material such as hair mixed in the drainage 2 Can be prevented from being entangled with each other, and the open state of the drainage passage portion 33 can be reliably maintained.

In the above embodiment, the screen 31
The main body portion 32 has been described as having a conical shape in which the vertex is upward and the diameter is gradually increased from the upper end to the lower end. However, for example, as shown in FIG. The main body 32a has a three-sided pyramid shape that gradually widens toward the side, or widens, or a polygonal main body such as a four-sided pyramid, a five-sided pyramid, and a six-sided pyramid that gradually expands from the upper end to the lower end (not shown). Or a truncated cone shape with the upper end cut out,
Even if the main body has a truncated pyramid shape, it is possible to obtain substantially the same operational effects as the conical main body 32.

In each of the above embodiments, the reaction tank 5 is described as an anaerobic reaction tank such as a denitrification tank. However, for example, the reaction tank 5 may be an aerobic reaction tank such as a nitrification tank, In this case, an aerobic microorganism such as nitrifying bacteria is used as the immobilized microorganism. Although not shown, when the reaction tank 5 is an aerobic reaction tank, it is preferable to provide an aeration means for supplying a gas containing oxygen (eg, air) into the cylindrical body 13.

The aeration means is constructed such that gas is jetted from the tip side of the supply pipe to a predetermined position in the cylindrical body 13, for example, a position in the vicinity of the lower part of the rotary vane 24, by the operation of a blower such as a blower. The gas bubbles supplied by the aeration means are cut by the substantially horizontal swirling flow generated in the cylindrical body 13 together with the downward flow A by the rotation of the rotary blades 24, and the surface area per bubble volume increases. , The dissolution efficiency of oxygen is increased. Further, since the bubbles generated by the aeration means do not come into direct contact with the rotary blades 24, the bubbles do not stay and accumulate near the rotary blades 24, and a stable swirling circulation flow is generated throughout the reaction tank 5. Furthermore, since gas-liquid contact is performed at a relatively deep position in the reaction tank 5, the water pressure increases the dissolution efficiency of oxygen. On the other hand, a bubble removing means such as a chamber capable of removing bubbles so that the flow of the drainage 2 does not deteriorate even if bubbles such as air supplied into the tubular body 13 by the aeration means flow into the outflow pipe 41. May be provided in the middle of the drainage outflow means such as the outflow pipe 41.

Further, the descending flow generating means 21 may generate a descending flow in the tubular body 13 by blowing gas into the tubular body 13 without using the rotary vanes 24 such as an impeller. Good.

Further, the drainage passage portion 33 of the screen 31 is not limited to the one constituted by a plurality of elongated holes 34.
It may be configured by assembling rod-shaped steel materials (not shown) in a grid pattern.

Further, the carrier separating means such as the screen 31 for separating the carrier 3 and preventing the carrier 3 from flowing out of the reaction tank 5 is the upper portion of the main body 32, 32a having the drainage passage 33 of a predetermined shape. It is not limited to the configuration in which the wastewater 2 is taken out as the treated water from substantially the entire circumference of the main body portions 32, 32a by being arranged over the entire circumference, and for example, the construction in which the wastewater 2 is partially taken out from a part of the main body portions 32, 32a in the circumferential direction. May be

Further, the gas collected by the bubble removing means such as a chamber provided in the middle of the drainage outflow means (that is, mainly nitrogen gas in the case of an anaerobic reaction tank, mainly air in the case of an aerobic reaction tank) is exposed to the atmosphere. Alternatively, the gas may be discharged to a cylindrical body or a return pipe (not shown)
It may be configured to return it to the inside of 13.

Further, the gas collected by the bubble removing means may be recovered by the recovering means (not shown) without being released to the atmosphere to effectively utilize the gas.

Further, the outflow pipe 41 for outflowing the wastewater 2 after the purification treatment in which the carrier 3 is separated and removed to the outside of the reaction tank 5 is not necessarily required, and the wastewater 2 after treatment is taken out by a wastewater extraction means such as a pumping means. You may do it.

The carrier separating means such as the screen 31 is
The downward flow A may be converted into a curved inclined flow that is inclined with respect to the vertical direction. For example, the conical body is not limited to a shape having a linear inclined surface, that is, a triangular shape having a straight hypotenuse when viewed from the side, and for example, a curved inclined surface (concave or convex). A shape having a curved inclined surface), that is, a triangular shape having a hypotenuse of a curved line when viewed from the side may be used. Similarly, the pyramidal main body is not limited to a shape having a flat inclined surface, and may have, for example, a shape having a curved inclined surface curved concavely or convexly.

[0051]

According to the first aspect of the present invention, the carrier is separated and removed from the wastewater flowing out of the cylindrical body through the lower surface opening by the downflow generated by the downflow generating means, and the downflow generated by the downflow generating means. Since the carrier separating means for converting the above into an inclined flow in the direction inclined with respect to the vertical direction is arranged at the lower position of the tubular body, the swirling circulation flow, which is a part of the downward flow in the tubular body, can be properly provided in the reaction tank. It can be generated and the purification treatment efficiency can be sufficiently enhanced.

According to the second aspect of the present invention, the carrier separating means having the conical main body portion and the drainage passage portion formed in the main body portion has a simple structure, but has a simple structure. A swirling circulation flow having a downward flow as a part can be appropriately generated in the reaction tank, and the purification treatment efficiency can be sufficiently enhanced.

According to the third aspect of the present invention, the carrier separating means having the pyramidal main body and the drainage passage formed in the main body has a simple structure, but has a simple structure. A swirling circulation flow having a downward flow as a part can be appropriately generated in the reaction tank, and the purification treatment efficiency can be sufficiently enhanced.

According to the fourth aspect of the invention, since the drainage passage is composed of a plurality of elongated holes having a longitudinal direction in the direction of the inclined flow, for example, the entanglement of fibrous substances mixed in the drainage is prevented. it can.

According to the fifth aspect of the present invention, by drivingly rotating the plurality of rotary blades in the cylindrical body, it is possible to reliably generate the downward flow in the cylindrical body.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a water treatment device of the present invention.

FIG. 2 is a perspective view showing a screen of the same water treatment device.

FIG. 3 is a perspective view showing another embodiment of the above screen.

[Explanation of symbols]

1 Water treatment device 2 drainage 3 carriers 5 reaction tanks 11 Top opening 12 Bottom opening 13 tubular 21 Downflow generator 24 rotating blades 31 Screen as carrier separating means 32, 32a body 33 Drainage passage 34 long hole A downflow B inclined flow

Claims (5)

[Claims] 1. A water treatment device for purifying wastewater using a carrier holding microorganisms, comprising: a reaction tank for storing wastewater containing a carrier holding microorganisms; and an axial direction up and down in the reaction tank. A cylindrical body having upper and lower openings, which are arranged so as to coincide with each other in direction, and which has an upper surface opening portion and a lower surface opening portion; downflow generating means for generating a downward flow in the cylindrical body; The carrier is separated and removed from the drainage flowing out of the tubular body through the lower surface opening by the downflow generated by the downflow generating means, and the downflow generated by the downflow generating means is vertically moved. And a carrier separating means for converting to a tilted flow in a tilted direction. 2. The carrier separating means is located concentrically with the cylindrical body, and has a conical main body whose diameter gradually increases from the upper end to the lower end, and an opening is formed in this main body to allow passage of the carrier. The water treatment apparatus according to claim 1, further comprising: a wastewater passage portion that separates and removes the carrier from the wastewater by prohibiting, and allows the wastewater that has been separated and removed from the carrier to pass through. 3. The carrier separating means is located on the same axis as the tubular body, and has a pyramidal main body that gradually expands from the upper end to the lower end, and an opening is formed in the main body to prevent the carrier from passing therethrough. The water treatment device according to claim 1, further comprising: a drainage passage portion that separates and removes the carrier from the wastewater, and allows the wastewater that has been separated and removed from the carrier to pass through. 4. The water treatment device according to claim 2, wherein the drainage passage is composed of a plurality of elongated holes having a longitudinal direction in the direction of the inclined flow. 5. The descending flow generating means has a plurality of rotating blades that are driven and rotated in the cylindrical body to generate a descending flow in the cylindrical body. Water treatment equipment.