JP2002263683A - Upward stream anaerobic processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an upward stream anaerobic processor which can reliably separate floating up granules, and can process organic drainage with a high efficiency because there is no possibility that the granules flow out of the treated water discharge means with treated water. SOLUTION: In this upward stream anaerobic processor, a sludge floor formed of self-pelletizing sludge is formed at the lower part inside the anaerobic treating vessel, a three-layer separation part for separating gas, liquid, and the sludge into three layers is formed above the sludge floor, and a gas stay part is formed in the top part. Organic drainage is treated by making the drainage flow upwards. A spray means to inject liquid toward the surface of the treated liquid is disposed in the gas stay part. A treated water discharge means is used as an overflow means in which the solid component separating member is provided at the treated water inlet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to the biological biology of microorganisms by flowing organic wastewater upward through a self-granulated sludge bed (hereinafter simply referred to as sludge bed) of microorganisms formed in an anaerobic treatment tank. The present invention relates to an upflow anaerobic treatment device (hereinafter, simply referred to as a treatment device) that decomposes organic matter in wastewater by a specific action.

[0002]

2. Description of the Related Art Conventionally, as a device for treating organic industrial wastewater or sewage such as food processing wastewater, fermentation plant wastewater, chemical plant wastewater, and pulp and paper plant wastewater, means for supplying treated water at the bottom and treatment water at the top. And anaerobic microorganisms mainly composed of methane bacteria are formed into particles (hereinafter, referred to as granules) below the inside thereof, and the granules are developed and retained at a certain height, and the sludge bed is formed. In the anaerobic treatment tank formed, the organic matter in the wastewater constitutes a granule by supplying organic wastewater from the treated water supply means to the lower part of the sludge bed and flowing the sludge bed upward. Biologically decomposed by anaerobic microorganisms, generated gas such as methane gas and carbon dioxide gas, treated water and granules are separated at the top, treated water is discharged from treated water discharge means, and generated gas is discharged from gas discharge means , Granule processing apparatus to precipitate the sludge bed is used.

[0003] In the above-mentioned treatment apparatus, anaerobic microorganisms that biologically decompose organic matter in wastewater are converted into particles using the microorganisms themselves or fine particles as nuclei. By being able to treat wastewater efficiently, the installation area of the device can be reduced,
There is an advantage that the generated methane gas can be used as a fuel or a raw material for producing chemical products, and a large number of them are installed.

Further, the height of the processing tank in a conventional general processing apparatus is increased by two to three times, and gas separation sections provided with a plurality of gas recovery hoods in the height direction are provided in two upper and lower stages. A high-efficiency processing apparatus that uses a recovered gas to generate an internal circulation flow of a liquid and can increase the organic substance load by a factor of two to three times as compared with the prior art is disclosed in
Japanese Patent Application Laid-Open No. 1-71896, and Japanese Patent Application Laid-Open No. 61-204093 discloses a high-efficiency processing in which a gas separation unit is provided with a three-stage gas recovery hood at a staggered position in the height direction. An apparatus is described.

[0005]

In a conventional general treatment apparatus, turbulent flow occurs in the liquid in the treatment tank due to the generated methane gas. Therefore, when the upward flow velocity of the water to be treated is increased, the granules are generated in the treated water. There is a risk that the water will flow out of the treated water discharge means. Also, when the upward flow velocity of the water to be treated is increased, the sludge load is locally overloaded, acid-producing bacteria grow densely on the granule surface, and the structure of the granule becomes a structure that is difficult for gas to permeate, Since the specific gravity of the granules is reduced and the granules easily flow out, it has been difficult to increase the processing efficiency under high-speed and high-load conditions. Also, in the configuration of the high-efficiency processing apparatus, a large number of pipes and gas collection
The arrangement of the nodes causes the apparatus to be more complicated than necessary, and also raises the cost of equipment. Therefore, the present invention has been made in view of the above-mentioned problems of the prior art, and it is possible to reliably separate the floating granules, and there is no possibility of flowing out of the treated water discharging means with the treated water. The purpose of the present invention is to provide an upward anaerobic treatment device capable of efficiently treating effluent wastewater.

[0006]

The gist of the present invention for achieving the above object is as follows.
A sludge bed formed by self-agglomerated sludge in the anaerobic treatment tank provided with a treated water supply means at the bottom and a treated water discharge means and a generated gas discharge means at the top. A three-layer separation part for separating into three layers of gas, liquid and sludge at the upper part of the sludge bed and a gas retention part at the top,
In an upward anaerobic treatment apparatus for treating an organic wastewater by flowing it upward, a spray means for spraying a liquid toward a treatment liquid surface is disposed in the gas retaining section, and the treated water discharge means is treated. An upflow anaerobic treatment device characterized by an overflow means provided with a solid content separation member at a water inlet. As the solid content separation member provided at the treated water inlet of the overflow means, a member formed of a notch, a slit, a lattice, a wire mesh, or the like can be used. Any structure can be used as long as the microbial particles that have floated up with the air do not flow out.

[0007] With the above structure, the air bubbles adhering to the floating granules can be separated and removed by the spraying means, and the granules can be broken to separate the enclosed air bubbles. Since the granules are surely separated, the clarity of the treated water is increased, and the decrease in the concentration of microorganisms due to the outflow of the granules is prevented, so that highly efficient treatment is possible.

[0008]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a system diagram of an upflow anaerobic treatment device according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a cylindrical anaerobic treatment tank having a closed structure (hereinafter simply referred to as a treatment tank), but may be a rectangular treatment tank. At the lower part of the treatment tank 1, there is provided treated water supply means 2 to which a treated water supply passage 10 is connected, and at the upper part, an overflow having a solids separation member 5 at the treated water inlet. Means 4 is provided, and the treated water discharge channel 12 is connected. On the top, a generated gas discharging means 1 provided with a gas suction device (not shown)
1 is provided.

In the treatment tank 1, a sludge bed A formed by self-agglomerated sludge is provided below, and gas is provided above the sludge bed A.
A three-layer separation part B for separating into three layers of liquid and sludge and a gas retention part C are formed at the top. The three-layer separation part B includes a mountain-shaped collision plate 3a in a lower stage and a gas hood 3b in an upper stage. There is provided a gas collector 3 which is arranged in a zigzag manner, forms a flow path for meandering and raising the liquid, and collects the generated gas and causes the floating granules 9 to stay and settle. Also,
The liquid is sprayed toward the processing liquid surface in the gas retaining section C to remove and remove the bubbles attached to the floating granules 9 and to break the granules 9 to separate the enclosed bubbles. A spray means 6 is arranged. In addition, the generated gas collected by the gas hood 3b is transferred to the gas retaining section C.
However, the collected product gas may be directly extracted and stored in a gas tank (not shown) or the like. Further, the three-layer separating section B may have a gas collector provided with a plurality of gas hoods above and below, or a configuration provided with a plurality of gas collectors above and below. Further, a treated water storage tank 7 for storing a part of the discharged treated water is provided, and a treated water supply pump 8 is provided, and circulating water and spray for maintaining a predetermined upward flow velocity in the treatment tank 1 are provided. -It is configured to be supplied as spray water of the means 6.

As the solids separating member 5 provided at the treated water inlet of the overflow means 4, a notch, a slit, a grid, or a plate member formed of a wire mesh or the like is used. Although it is possible, any structure may be used as long as it does not allow the microbial particles floating with the treated water to flow out.

The treated water supply means 2 preferably distributes the treated water uniformly upward in the entire horizontal section of the treatment tank 1. It is preferable to dispose over almost the entire bottom surface,
The member for supplying the water to be treated in the tangential direction in the treatment tank 1 may be used, but is not limited thereto.

The operation of the present invention will be described below with reference to the drawings. Water to be treated as organic wastewater such as food processing wastewater is supplied to the lower part of the treatment tank 1 from the treatment water supply passage 10 via the treatment water supply means 2, and the inside of the treatment tank 1 is uniformly turned upward. The sludge bed A of the granules 9 is formed by the microorganisms such as methane bacteria which are self-granulated by using the initially filled sewage sludge as a seed microorganism by distributing the sludge as a stream. 9 may be filled.

In the water to be treated supplied into the treatment tank 1, organic substances in the water to be treated are decomposed by the biological action of microorganisms while flowing upward through the sludge bed A to produce methane gas, carbon dioxide gas and the like. Is done. In addition, in the conventional treatment apparatus, the upward flow velocity of the water to be treated is low to prevent the granules 9 from flowing out due to the expansion and deployment of the sludge bed A (for example, 1 to 2 m / hr). ), The inorganic solids contained in the water to be treated are easily trapped by the granules 9, and the biological activity of the sludge cannot be maintained at a high level. Although it was difficult to increase the processing efficiency under high load conditions, the processing apparatus of the present invention can completely prevent the granules 9 from flowing out, and therefore has a high upward flow velocity (for example, 3 to 10 m / h).
r), the sludge bed A can be positively expanded and deployed, and the contact efficiency between the water to be treated and the granules 9 can be increased. Further, the supply amount of the water to be treated can be increased, and the treatment efficiency can be increased under high-speed and high-load conditions.

The water to be treated, in which the organic matter is decomposed by the microorganisms in the sludge bed A, further rises and rises in the gas collector 3 in the three-layer separation section B.
, The floating granules 9 are separated by the lower chevron impact plate 3a and settled and circulated to the sludge bed A, and a part of the floating granules 9 and generated gas meander upward with the processing liquid, Floating granules 9 by upper gas hood 3b
And the product gas. Generated gas is gas hood 3b
The floating granules 9 are collected in the gas storage section C, and settle on the sludge bed A while staying.

The water to be treated, from which the product gas and the granules 9 have been separated by the gas collector 3 of the three-layer separation section B, rises further, reaches the gas retaining section C, and the remaining product gas is separated by standing. The remaining granules 9 are separated by the solid content separation member 5 provided at the treated water inlet of the bar flow means 4 and discharged out of the treated tank from the treated water discharge channel 12 as clear treated water. Further, the generated gas separated into the gas retaining section C is collected from a generated gas discharging unit to a gas tank (not shown) through a gas suction device (not shown).

The water to be treated staying in the gas staying section is:
The treated water sprayed from the spray means 6 removes and removes the air bubbles adhered to the remaining floating granules 9 and breaks the granules 9 to separate the enclosed air bubbles, so that the air bubbles are efficiently separated. The granules 9 can be settled off.

The clear treated water discharged from the treated water discharge channel 12 to the outside of the treated tank 1 is discharged to the outside of the system. A part of the treated water is stored in the treated water storage tank 7 and then supplied to the treated water supply tank 7. In order to maintain a predetermined upward flow velocity in the treatment tank 1 through the treatment water circulation flow path 14,
It merges with the water to be treated and mixes with the water to be treated, is circulated in the treatment tank 1, and the remaining treated water is supplied as spray water of the spray means 6 through the spray water supply flow path 13. You.

[0019]

According to the present invention, the floating granules can be reliably separated, and there is no possibility that the floating granules will flow out of the treated water discharge means with the treated water. Sexual processing device.

[Brief description of the drawings]

FIG. 1 is a system diagram of an upward anaerobic treatment device according to an embodiment of the present invention.

[Explanation of symbols]

 1: Anaerobic treatment tank 2: Treatment water supply means 3: Gas collector 4: Overflow means 5: Solids separation member 6: Spray means 7: Treated water storage tank 8: Treated water supply pump 9 : Granule A: Sludge bed B: Three-layer separation section C: Gas retention section

Claims (1)

[Claims] 1. An anaerobic treatment tank provided with a treated water supply means at a bottom part, a treated water discharge means and a generated gas discharge means at an upper part, and self-granulated sludge below the anaerobic treatment tank. The formed sludge bed, a three-layer separation part for separating into three layers of gas, liquid and sludge at the upper part of the sludge bed and a gas retention part at the top are formed to process organic wastewater by flowing upward. In the upward flow anaerobic treatment apparatus, a spray means for injecting a liquid toward a treatment liquid surface is disposed in the gas retaining section, and a solids separation member is provided at the treatment water inflow port for the treatment water discharge means. An upflow anaerobic treatment device characterized by an overflow means.