JPH0648899U - Anaerobic treatment filter material - Google Patents

Abstract

(57) [Summary] [Purpose] To improve the solid matter trapping property of the filter for anaerobic treatment and to improve the treatment performance of the anaerobic treatment section. [Constitution] In a filter medium for anaerobic treatment which irregularly fills the inside of an apparatus for treating sewage by anaerobic microorganisms, the filter medium for anaerobic treatment has a cylindrical shape and its side wall has an outer shape of 0.
A net-like body having a predetermined thickness is formed of a thread-like body of a thermoplastic resin having a thickness of 5 to 2.5 mm.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention is mainly used in an anaerobic treatment section of a sewage purification device, and relates to an anaerobic treatment filter that does not cause clogging and has excellent solid matter trapping ability.

[0002]

[Prior art]

 BACKGROUND ART So-called anaerobic microorganism purification treatment of sewage has been widely used in various purification apparatuses. FIG. 5 shows an example of a sewage treatment apparatus using the anaerobic microorganism, and is a schematic sectional view of a so-called anaerobic filter bed contact aeration type combined treatment septic tank. That is, the sewage (human waste or household wastewater) 3 that has flowed into the first anaerobic filter bed tank 2a from the inflow port 1 enters the second anaerobic filter bed tank 2b through the advection pipe 4, and first, both anaerobic filter bed tanks 2a. , 2b, undergoes anaerobic treatment by anaerobic microorganisms. The sewage water 3a that has been anaerobically treated in the anaerobic filter bed tank 2 continuously enters the contact aeration tank 6 through the communication hole 5, is purified by aeration treatment, and then passes through the settling tank 7 and the disinfection tank 8 and then the discharge port. It is discharged from 9 to the outside.

Therefore, the solid matter in the wastewater 3 is trapped inside the anaerobic filter bed tank 2 to prevent the solid matter from flowing into the contact aeration tank 6 and to propagate the anaerobic microorganisms. The anaerobic treatment filter medium 10 having an appropriate thickness is filled in order to promote the anaerobic treatment performance. However, the anaerobic treatment filter medium 10 has an essential requirement that it has to satisfy simultaneously the contradictory performances that it is excellent in capturing solids and is unlikely to cause clogging. There are advantages and disadvantages to each type of anaerobic filter material that is used.

For example, a conventional anaerobic filter material of this type is formed into a skeleton-like ball body A having an outer diameter of about 150 mmφ by using polyvinyl chloride or the like. 64 m ² / m ³ ), a thin corrugated sheet B having a corrugation of about 80 mm 2 and a height of about 60 mm made of polyvinyl chloride (specific surface area of about 55 m ² / m ³ ), a mesh formed of polypropylene, etc. Of 60 mm thick thick plate with a pitch of 100-300 mm and a height of 150-350 mm bent into a corrugated thick corrugated plate C (specific surface area of about 45 m ² / m ³ ) and polyethylene etc. , Which is molded into a cage-like cylindrical body D having a length of 80 mm (specific surface area 40 m ² / m ³ ) and the like.

However, in the anaerobic treatment filter material of the skeleton-like ball body A, the thin corrugated plate body B, the reticulated thick corrugated plate body C and the basket-like cylindrical body D, sludge retention ability, sludge trapping ability, sludge dispersibility, gas There are merits and demerits in terms of ease of removal and compaction within the filter bed, and as a result, the treatment in the anaerobic filter bed tank 2 becomes insufficient and sewage flowing from the anaerobic filter bed tank 2 into the contact aeration tank 6 is discharged. However, there is a problem that the BOD value in the inside cannot be reduced sufficiently and the tank volume of the entire purification device cannot be reduced.

[0006]

[Problems to be solved by the device]

 The present invention has the above-mentioned problems in the conventional anaerobic treatment filter medium, that is, the sludge retention ability and sludge capturing ability of the anaerobic treatment filter medium are relatively low, sufficient anaerobic treatment is difficult, and the size of the treatment apparatus is significantly reduced. It aims to solve the problem of being unmeasurable, has high sludge trapping ability and sludge holding capacity, and is capable of highly anaerobic treatment of sewage without causing clogging, and easy degassing and cleaning. It is intended to provide a filter medium for anaerobic treatment which can be manufactured at a relatively low cost.

[0007]

[Means for Solving the Problems]

 The present invention relates to a filter medium for anaerobic treatment that irregularly fills the inside of a device for treating sewage by anaerobic microorganisms. The filter medium for anaerobic treatment has a cylindrical shape and its side wall has an outer shape of 0.5-2. The basic structure of the invention is to form a mesh body of a predetermined thickness made of a thread-shaped body of thermoplastic resin of 0.5 mm.

[0008]

[Action]

 The solid matter contained in the sewage flowing into the anaerobic treatment section is trapped by the filter medium while passing through the filter bed made of the anaerobic treatment filter medium, and so-called filtration treatment is performed. Further, by capturing and retaining the solid matter containing sludge in the anaerobic treatment filter medium, the anaerobic microorganisms in the sludge are sufficiently propagated, and the decomposition treatment of the wastewater by the anaerobic microorganisms is promoted.

[0009]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a filter medium S for anaerobic treatment according to the present invention, and FIG. 2 is a cross-sectional view of FIG. The anaerobic treatment filter medium S is formed into a cylindrical body having a mesh-like side wall Sa made of a filamentous material of a thermoplastic resin such as polypropylene or polyethylene by a method described later, and its shape and dimension are The diameter D is selected to be 50 mm to 300 mm, the length L is selected to be 20% to 300% of the outer diameter D, and the thickness t of the mesh side wall Sa is selected to be about 10 to 35% of the outer diameter D. The thermoplastic resin filaments forming the mesh side walls Sa are selected to have an outer diameter of about 0.5 to 2 mmφ, and a large number of curls having a diameter of about 5 to 30 mm are fixed to each other. It is in the state of doing.

The outer dimensions of the filter medium S are mainly determined by the capacity of the anaerobic filter bed tank to which the filter medium S is applied, the characteristics of sewage, the anaerobic treatment performance (sludge trapping ability, sludge retention rate, etc.), the method for producing the filter medium S, and the like. It is something. For example, if the outer diameter D of the filter medium S is 50 mmφ or less and 300 mmφ or more, the manufacturing thereof becomes difficult, and from this point, the outer diameter D is limited to about 50 to 300 mmφ. The thickness of the filter medium wall is determined mainly from the viewpoints of clogging and sludge trapping ability. When the outer diameter D of the filter medium S is 50, t = 5 mm to 17.5 mm, and It has been confirmed by an actual machine test that t = 30 to 105 mm is optimal when the outer diameter D is 300 mmφ. Further, the length L of the filter medium S is mainly determined by the capacity (outer dimensions) of the anaerobic filter bed. When the outer diameter D is 50 mmφ, L = 10 to 150 mm, and the outer diameter D It has been confirmed by the above-mentioned actual machine test that it is convenient to select L = 300 to 600 mm when L is 300 mmφ in terms of the filling property and repair (cleaning) of the filter medium S.

FIG. 3 shows an example of a method for manufacturing the filter medium S according to the present invention, and FIG. 4 is a cross-sectional view of the filter medium of FIG. In the figure, 11 is a synthetic resin supply device, 12 is a nozzle, 12a is a nozzle hole, 13 is a filament, 14 is a cooling water tank, 15 is cooling water, 16 is a drawing roller, 17 is a blower, and 18 is a delivery. It's Laura. In the synthetic resin supply device 11, the thermoplastic synthetic resin material heated and melted by the heater 11a is kneaded by the stirring blade 11b, and the synthetic resin material kneaded to have an appropriate viscosity is twisted by the screw conveyor 11c. The pressure is fed into the nozzle 12. The synthetic resin material pressure-fed into the nozzle 12 is spun out from the nozzle hole 12a and becomes a filament 13 and descends. At this time, since the so-called twist is applied to the thermoplastic synthetic resin material supplied to the nozzle hole 12a by the screw conveyor 11c, the filament 13 spun from the nozzle hole 12a is not linear. Instead, it twists and gradually descends.

The filament 13 that has descended in a twisted state is rapidly cooled by touching the cooling water 15 in the cooling water tank 14. Further, the solidification force is applied by the rapid cooling, and the lower end portion of the filamentous body 13 is deformed into a so-called curl shape. Further, the plurality of curls 13a formed in the vicinity of the upper surface of the cooling water enter the cooling water 15 in a state of being in contact with each other and fused, and are hardened to each other by hardening the contact portion. . In addition, warm air is sent to the vicinity of the water surface of the cooling water tank 14 by a blower 17 at an appropriate wind speed, and the plurality of curls 13a formed above the cooling water surface are forcibly brought into contact fusion by the hot air. Will be done.

A combination of a plurality of curls 13a that have been pulled down into the cooling water 15 and hardened, that is, a cylinder A ′ composed of a net-like side wall Sa having a thickness t is disposed slightly below the cooling water surface. Further, it is drawn into the cooling water 15 by the drawing-in roller 16 and continuously drawn out of the machine through the sending-out roller 18. In this embodiment, as shown in FIG. 4, the nozzle holes 12a (diameter of about 0.5 to 2.0 mmφ) of the nozzle 12 are arranged in a ring shape at intervals of 5 to 50 mm so that the cross section is circular. A tubular body A ′ having a shape is formed, and the tubular body A ′ is cut into an appropriate length dimension to obtain the anaerobic treatment filter medium S. The diameter of the curl due to the twist of the filament 13 can be changed by adjusting the viscosity of the synthetic resin material, the twisting force by the screw conveyor 11c, the nozzle diameter, etc., and is usually selected to be 5 to 30 mmφ.

The anaerobic treatment filter medium S manufactured as described above is placed in the anaerobic treatment section in a space between the filter medium receiver and the filter medium retainer, which are horizontally arranged with a certain space therebetween, to the space of about 30 minutes. It is filled irregularly at a rate of about 1500 pieces / m ³ and a so-called anaerobic treatment filter medium is formed.

Table 1 shows a comparison between the trapping property of the filter for anaerobic treatment according to the present invention and the trapping property of this type of conventional filter for anaerobic treatment, which was actually measured using a simulated sludge described later. Is.

[0016]

[Table 1]

That is, an anaerobic filter bed of 1 m × 1 m × 0.5 m (height) is formed inside the anaerobic filter bed tank having a volume of about 1.3 m ³ , and SS is introduced into the anaerobic filter bed tank from the inlet. The artificial sludge with a concentration of 3200 ppm was continuously supplied at a flow rate of 20 l / min, and the SS concentration in the outflow water discharged from the discharge port was continuously measured and the average value was calculated. It is a fixed one. In this test, it goes without saying that the total surface area of the filter media of each anaerobic filter bed is set to the same value. As is clear from Table 1, about 75% [(3200-800) / 3200] of sludge is captured by the filter medium S of the present invention, and the capture rate of the conventional skeleton-like ball filter medium A 63 % [(3200-1200) / 3200], the sludge capture rate is significantly improved.

[0018]

[Effect of device]

 As described above, in the present invention, the filter medium S is formed into a cylindrical shape having a net-like side wall of a predetermined thickness by gathering a plurality of plastic filaments curved in a curl shape and fixing them together. . As a result, as compared with the conventional anaerobic treatment filter medium, the sludge capture rate can be greatly improved without causing the filter medium to be clogged, and the treatment capacity in the anaerobic treatment unit is significantly improved. Further, the anaerobic treatment filter medium of the present invention can easily and continuously produce a large amount of a filter having a desired external dimension, and the production cost of the filter medium can be reduced. As described above, the present invention has excellent practical utility.

[Brief description of drawings]

1 is a perspective view of a filter medium for anaerobic treatment according to the present invention.

FIG. 2 is a sectional view taken along the line E-I of FIG.

FIG. 3 is an explanatory diagram of a method for producing a filter medium for anaerobic treatment.

FIG. 4 is an enlarged cross-sectional view of the roller of FIG.

FIG. 5 shows an example of a combined treatment septic tank using a filter material for anaerobic treatment.

[Explanation of symbols]

 1 is inlet 2 is anaerobic filter bed 3 is sewage 4 is advection pipe 5 is communication hole 6 is contact aeration tank 7 is precipitation tank 8 is disinfection tank 9 is discharge port 10 is anaerobic filter S is anaerobic Filter material for treatment Sa is a mesh side wall 13 is a filamentous body

Claims (3)

[Scope of utility model registration request] 1. A filter medium for anaerobic treatment, which is irregularly filled into a treatment apparatus for wastewater by anaerobic microorganisms, wherein the filter medium for anaerobic treatment has a cylindrical shape and its side wall has an outer shape of 0.5 mm to. A filter material for anaerobic treatment, which is a net-like body having a predetermined thickness and made of a filamentous material of a thermoplastic resin of 2.5 mm. 2. The shape and the outer diameter are 50 mm to 300 m.
The filter medium for anaerobic treatment according to claim 1, wherein m is a cylindrical shape having a length of 20% to 300% of the outer diameter and a side wall thickness of 10% to 35% of the outer diameter. 3. The side wall has a diameter of 5 to 30 made of filaments.
The filter medium for anaerobic treatment according to claim 1 or 2, which is formed by fixing a large number of mmφ loop bodies to each other.