JPH02152595A - Treatment of organic waste water - Google Patents

Abstract

PURPOSE:To separate sludge stuck to the surfaces of the synthetic fibers in excess and to maintain the purifying function of a contact treating mechanism having rotating disks made of synthetic fibers over a long period of time by feeding air to the bottoms of the disks partially immersed in waste water having high BOD. CONSTITUTION:Rotating disks 11 having 85-99% void volume obtd. by compression-molding synthetic fibers of 0.5-1.2mm diameter mixed at random are partially immersed in org. waste water and rotated. The disks 11 are alternately brought into contact with the org. waste water and air and aerobic micro-organisms are stably stuck and propagated on the surfaces of the fibers. When org. waste water having >=800ppm BOD is introduced into a contact treating mechanism 1 having the disks 11, air is fed to the disks 11 with an air blowing mechanism 10 and sludge layers stuck to the surfaces of the fibers in excess by the aerobic micro-organisms are separated by ascending flows of the air. At the same time, the blocked inter-fiber voids in the disks 11 are made vacant so that air is effectively fed to the aerobic micro-organisms.

Description

[Detailed Description of the Invention] "Object of the Invention" The present invention relates to a method for treating organic wastewater, and provides a method that can stably, precisely, and efficiently purify organic wastewater with a high BOD concentration over a long period of time. This is what we are trying to provide.

(Industrial Application Field) A technology that purifies wastewater with high BOD concentration discharged from various industries and living environments without diluting it further and over a long period of time.

(Prior Art) It is well known that rivers, lakes, etc. are contaminated by domestic wastewater in cities and organic wastewater from various food industries. It can be broadly divided into biochemical methods that utilize the oxidation or nitrification effect caused by the proliferation of microorganisms, and chemical methods that use various chemicals. The latter, chemical method, is a method in which organic wastewater is treated directly by adding various chemicals depending on its contamination state, so it is naturally possible to treat wastewater quickly. Since it is necessary to add chemicals for each wastewater treatment, and therefore the running cost for each treatment increases, it cannot be commonly used in the treatment of organic wastewater, so the former biochemical method is recommended. It is gradually becoming popular.

In other words, treatment methods using microorganisms include the activated sludge method, in which air is blown into the sewage in the treatment tank, the contact oxidation method, in which a contact material is placed in the tank (immersion filter method), and the trickling filter method. However, by attaching a large number of comparatively lightweight and strong rotating plate members to a rotating shaft, and immersing approximately 40% of the body surface area of the rotating plate parts, and rotating them at low speed, the rotating plate group can be removed from the air and sewage. A preferred method is the rotating plate contact method, in which wastewater is purified by microorganisms attached to the rotating plate bodies and their surfaces, and is described in, for example, ``Water Treatment Technology'' magazine, Vol. 24, 1983. It is introduced in No. 10, pages 35-40. That is, according to this method, it is not necessary to blow air into the sewage in the tank, and there is no need for special water sprinkling (furthermore, there is no need to return sludge, so it is said to be the most energy-saving method, and it is already It is being used in a considerable number of treatment plants in Japan.However, even in the case of this advantageous rotating disk method, in the case of conventional rotating disks, the disk bodies are placed in close contact with each other. However, since the surface area per unit volume (m3) is limited, it is difficult to obtain efficient oxygen supply and the favorable oxidizing action of microorganisms associated with it.

Therefore, in order to eliminate the above-mentioned disadvantages, the present inventors adopted a slowly decomposing structure made by interlacing flexible synthetic fiber materials as the rotary body, aimed at preferable air supply, and moreover, microorganisms were not contained in the fiber structure. For example, Japanese Utility Model Application No. 582161 (Utility Model Application No. 59-110096 ), ■ Japanese Utility Model No. 176665 (Utility Model Application No. 60-86500), and ■ Japanese Utility Model No. 59-116464 (Utility Model Application No. 61-33696). That is, according to the prior art of the present inventors, it is possible to form a porosity state of 95% or more with the fiber material and make the contact area about 180 to 250 m', and for example, it is possible to operate in a 40% submerged system. In such cases, it has been confirmed that microorganisms actively adhere to and proliferate on the surrounding surface of the fibrous material after approximately 20 days of operation, and
■When it comes to suggestions like
It has been experimentally confirmed that stable operation can be achieved without separation of fiber materials or breakage of various parts due to adhesion of sludge. It has also been confirmed that the temperature reaches 8 to 15 times that at the start of operation.

(Problems to be Solved by the Invention) The above-mentioned proposal by the present inventors utilizes a fine structure in which synthetic fibers are interwoven, and supplies organic wastewater and air into the structure by rotating a rotary disk. Since this process is repeated alternately and at appropriate time intervals, aerobic microorganisms (fungi) can be grown efficiently, and BO
The D load can be improved to at least several times or more than that of the filter bed method, which is considered to be an effective conventional equipment, and effective treatment with a removal rate of 60 to 95% can be ensured, making it practical in various fields. has been made into However, with the improvement of the performance of the equipment by the inventors and others, and also due to stricter wastewater regulations, the BODI degree of raw water (organic wastewater) used in conventional equipment has increased to 500 pp.
In many cases, we are treating highly concentrated wastewater that exceeds the limit of 11,000 pp or more and has a fine level of 38 min. without doubling or more, thus eliminating the need for extra clean water, streamlining the treatment, and achieving advantageous operations from all aspects without generating large amounts of treated water. becomes possible.

However, even in operations using such highly concentrated wastewater, it is possible to carry out stable and efficient purification treatment for at least two months, and in some cases several months, but continuous operation beyond such limits is not possible. As a result, the sludge around the fibers, which had previously adhered and grown smoothly, suddenly falls off, resulting in a significant drop in processing efficiency, and once this phenomenon occurs, it is extremely difficult to restore its functionality. Therefore, even if recovery treatment using diluted low-concentration wastewater is performed for several months or more, not only the rotary plate contact mechanism but also
It is not possible to restore the overall purification function, including the sedimentation tank that separates the treated liquid after treatment and removes the sludge, and to obtain a high level of treatment efficiency.

In other words, the high processing efficiency, which is several tens of times higher than that of conventional methods, rapidly decreases after being used for two to three months or several months as described above, and the mechanism to ensure advantageous operation is Despite the above-mentioned proposals by the present inventors regarding the improvement of the water quality, a situation arises in which it is difficult to obtain the originally high-efficiency purification treatment. Even if it is confirmed by the data, we have no choice but to follow the disadvantageous operation of purposefully diluting it.

``Structure of the Invention'' (Means for Solving the Problems) A synthetic fiber rotary disk made of synthetic fibers with a diameter of 0.5 to 1.2 mm intertwined irregularly and compression molded to have a porosity of 85 to 99%. The fibers are partially immersed in organic wastewater and rotated to alternately bring the organic wastewater into contact with air, allowing aerobic microorganisms to grow on the surface of the fibers to purify the organic wastewater as described above. When wastewater is subjected to sedimentation treatment and discharged, BOD? , organic wastewater with a concentration of 800 ppm or more is supplied, and during the contact treatment, air is supplied to the synthetic fiber rotary disk part to control the sludge film thickness due to aerobic microorganisms that adhere to and form on the synthetic fiber surface. An organic wastewater treatment method that supplies and treats wastewater.

(Function) By using synthetic fibers with a diameter of 0.5 to 1.21 mm, it has the strength to withstand the adhesion and growth of sludge caused by vigorous aerobic microorganisms, and also forms voids with a porosity of 85% or more. The supply of organic wastewater and air during rotation of the rotary disk is facilitated, efficient proliferation on the fiber surface is achieved, and a high removal rate of the BOD content of the organic wastewater is achieved.

BOD concentration in organic wastewater (raw water) supplied to 8
By setting the concentration to 00 ppm or more, it is possible to purify high-concentration wastewater discharged from various food manufacturing facilities and other sources without diluting it, making it unnecessary or significantly reducing the amount of clean water used for dilution, and reducing the amount of treated wastewater. This results in a significant reduction.

By supplying air to the synthetic fiber rotary disk, the film thickness of the sludge that adheres to or is about to be produced in excess on the peripheral surface of the synthetic fibers is controlled, and the voids between the fibers are prevented from being clogged. Air and organic wastewater are always supplied smoothly, and the generation or proliferation of anaerobic microorganisms on or near the fiber material is completely eliminated or restricted. Therefore, the rapid shedding of sludge caused by such anaerobic microorganisms is prevented, and the interfering effect of the anaerobic microorganisms on the rotating contact mechanism or the settling tank used continuously therewith is prevented.

As a result, as described above, the vigorous aerobic microorganisms can perform highly efficient cleaning treatment for highly concentrated wastewater over a long period of time.

(Example) To explain the present invention as described above in more detail, one of the general structural relationships of the apparatus for carrying out the present invention will be described.
An example is shown in Fig. 1, in which the organic wastewater described above is appropriately received in the raw water pit (2), coarse particles are removed by a screen (4), and then the organic wastewater is transferred to the adjustment tank (3). A fixed amount of synthetic fibers is supplied to a contact processing mechanism (1) equipped with a synthetic fiber rotary disk (11).

In other words, the raw water (organic wastewater) obtained from the food industry and other wastewater sources, even if it is domestic wastewater from a general household, fluctuates considerably over time in its discharge amount and concentration, and this can be Raw water bit (2) and adjustment tank (3)
The adjusted state is constantly supplied to the contact treatment mechanism (1) for contact purification treatment.

The treated water from the contact treatment mechanism (1) is transferred to the aeration tank (5) as appropriate.
The sludge is sent to a sedimentation tank (6) through a sludge tank (6), where the settled sludge bones are separated, and then drained through a treatment water tank (7) and a disinfection tank (8). A sludge digestion tank (9) is installed as appropriate for the settling tank (6).
) is attached for digestion processing as shown in the figure.
In the present invention, an air blowing mechanism (10) is provided, which blows air into the adjustment tank (2) as appropriate, and a contact mechanism (
Air is blown into the synthetic fiber rotary disk (11) portion of 1). Although the one shown in Fig. 1 is relatively large and requires careful treatment, the one according to the present invention can be suitably simplified and implemented, and in some cases, the raw water supply section and the contact treatment mechanism ( 1) and settling tank (
6) may be used.

The specific structure of the synthetic fiber rotary disk (11) is based on the prior art described above, and as shown in FIG. On the other hand, a mixture of appropriate other fibers is cut into a predetermined length, and if necessary, subjected to a curling process under appropriate heating conditions, and then mixed and arranged in a relaxed state. Synthetic resin latex is sprayed onto the fibers in the form of a spray, the latex is made to flow along the fiber surface, and the latex is heat-treated in a state where it aggregates at the intersections of each fiber, and the fibers are fastened together at each intersection as described above. In addition, the curly bending process described above gives it bulkiness.

As mentioned above, the material plate (lla) obtained in the above manner does not allow the fastened fibers to partially fall off and separate due to vigorous growth of microorganisms and accompanying resistance or friction during rotation in the raw water. In order to prevent this, according to the method shown in the above-mentioned prior patent application No. 61-33696, the peripheral side of the material plate (lla) and the assembly member insertion hole (llb)
The parts are made into compressed welded parts (15) (15a), that is, by partially compressing and heating the thermoplastic synthetic fibers as described above, the thermoplastic synthetic fibers are welded. The pressed welded part (15) or (15a) forms a compressed dense state even when a certain amount of other fibers are blended, and becomes rigid like a simple synthetic resin molded plate.
is formed.

Furthermore, it is clear that it is preferable for the rotating body as described above to have a circular shape, and it is advantageous to form the material plate (lla) as a plurality of sector-shaped units. The material plate (11a) has its insertion hole (
It is assembled using a cylindrical spacing member (12) to the flattened weld (15a) formed in the 1l b) section. This spacing member (12) is connected to the shaft cylinder portion (21) as shown in FIG.
) is provided with a flange (22) facing each other at both ends, and a butterfly part (23) and a female thread part (24) are formed that protrude from the flange (22), respectively. With respect to one of the two spacing members (12) (12) located on both sides of the material plate (11a), with its female thread (24) inserted into the insertion hole (1lb),
Connect the butterfly part (23) of the other spacing member (12) to the female thread part (
24) By screwing into the rain spacing member (12) (
The compressed welded portion (15a) is sandwiched between the collar portions (22) (22) in (12). The above-mentioned insertion hole (llb
) are arranged for each material plate (113') as shown in Fig. 3, and these insertion holes (1l b
As shown in FIG. 3, a spacing member (12) is used for each of the parts ( ), and the collar part (22) is set in a state embedded in the pressed weld part (15a). In this way, when the spacing members (12) are sequentially screwed together in the axial direction and the material plate (lla) is inserted and supported between the flanges (22) of the spacing members (12), a rigid body is formed. The spacing in the thickness direction of each material plate (lla) is automatically determined based on the dimensions of a certain spacing member (2) and the thickness dimension of the rigid pressed welded part (15a), and the spacing in the thickness direction of each material plate (lla) is automatically determined. is taken and positioned.

Therefore, if the tightening rod (13) is inserted into the inner hole of the spacer member (12) installed in this way as shown in FIG. Each rotary disk (11) formed by
As shown in the figure, the straight flattened welded portions (15) on both sides of lla) are also substantially aligned.

The end plate (16) and rotary disk (11) as described above are supported on the machine frame (14) by a shaft rod (19), and are rotationally driven by a driving mechanism (17) such as a motor. The contact processing mechanism (1) is appropriately covered with a cover (1a).

The thickness of the thermoplastic synthetic fibers used for each material board (lla) and the porosity formed by it are selected as appropriate, but in the present invention, the conditions are such that sludge caused by microorganisms adheres to and propagates on the surface. Since it is rotated in the supplied wastewater, it requires considerable strength, and the diameter is preferably in the range of 0.5 to 1.2 mm, particularly 0.7 to 1.0 mm, and the diameter is preferably in the range of 0.5 to 1.2 mm. Rate is 85-99
%, especially about 89 to 98%. That is, by doing this, an appropriate supply relationship of raw water and air can be obtained,
Moreover, stable adhesion and growth of microorganisms can be achieved.

As mentioned above, in the operation of the above-mentioned equipment, a situation occurs in which the high level of processing efficiency rapidly decreases, and such a decrease in processing efficiency can be considered as follows. In other words, the proliferation of microorganisms (sludge) on the fiber surface, which is the media, progresses and completely covers the entire surface, and then the density of the film increases, and new cells cover the surface of the already formed film. As the proliferation progresses and these proliferations are obtained on the respective surfaces of adjacent fibers, the voids between the fibers are closed over a certain period of time, and ventilation and water supply are obstructed, especially at the inner fiber interface. As aeration and water supply become difficult, the aerobic microorganisms that were proliferating begin to die and cease to function aerobically, and anaerobic microorganisms emerge in their place, using the dead aerobic microorganisms as food and multiplying. In other words, when the lowest layer of the fiber boundary is eaten away by the generation and proliferation of these anaerobic microorganisms, the structure created by the aerobic microorganisms up to that point is lost, and gas is generated and a large amount of sludge is produced. It is assumed that this would result in a large amount of anaerobic microorganisms remaining in the contact mechanism layer and the sedimentation tank that is continuous with it. The generation and proliferation of original aerobic microorganisms are significantly inhibited by anaerobic microorganisms such as
Furthermore, it is not easy to completely kill or eliminate the remaining anaerobic microorganisms, so it is difficult to expect the aerobic microorganisms to grow as vigorously as before in the equipment where sludge has already fallen out. It was thought that this would be the case.

Therefore, in the present invention, in order to avoid the above-mentioned sudden and large falling off from the surface of the fiber material and to perform an operation that allows stable growth of aerobic microorganisms to continue over a long period of time, the above-mentioned contact mechanism (1) is used. Air is blown from the diffuser pipe (10) at the bottom of the synthetic fiber rotary plate (11) to form an upward air flow (bubbles), and the bubble upward force caused by this air and the associated burst force of the liquid flow or bubble This system applies a complex impact action or contact friction force, as well as a turbulent agitation action, to remove excessively adhered sludge. In other words, by removing the excess adhered sludge in this way, the spaces between each fiber are not blocked by sludge, and
Therefore, air is effectively supplied to the aerobic microorganisms adhering to each fiber surface, and the purification process is continued in an optimal state suitable for each substrate. Since sludge does not adhere excessively to each fiber surface and oxygen is continuously supplied to the fiber surface through the envelope membrane, the death of aerobic microorganisms on the fiber surface is almost eliminated, and anaerobic microorganisms are not generated. Since proliferation is suppressed, there is no fermentation or gas generation, and it is possible to accurately prevent large amounts of sludge from falling from the deep layer (fiber surface). Furthermore, by suppressing the generation and proliferation of anaerobic microorganisms, the interfering effects caused by anaerobic microorganisms in the contact treatment mechanism or settling tank are also eliminated.

Theoretically, it is preferable to blow air as described above from the time when sludge (aerobic microorganisms) with a thickness of about 0.2 mm has adhered to the fiber surface. It is not effective because there is no adhesion of excess sludge. In other words, by starting the purification process without blowing air and starting blowing air after a certain amount of sludge has adhered, it is possible to continue the purification process in the optimal state as described above over a long period of time. Become.

However, in actual operation, it is not easy to accurately determine the point in time when the above-mentioned appropriate sludge adhesion range shifts to the excessive sludge adhesion state. That is, it is not easy to measure the adhesion thickness in detail, and it is difficult to judge visually because the entire fiber surface has the same sludge color. One method is to determine the purification efficiency.In other words, since the purification efficiency decreases due to excess sludge adhesion, it is expected to detect this point and start air blowing. It is difficult to determine accurately. In other words, considerable equipment is required to analyze and determine efficiency, and generally samples are sent to a specific institution from time to time to obtain reports, and it takes a week or more to obtain such results. Because such a period of time is required, by the time such results are available, the results of the analysis will be quite old. In other words, the adhesion and proliferation of sludge varies depending on the supplied wastewater conditions and external temperature conditions, and aerobic microorganisms die on the fiber surface.
The generation and proliferation of anaerobic microorganisms is unavoidable, and there remains room for interference by the anaerobic microorganisms that are introduced.

Therefore, taking such relationships into account, in order to obtain stable operation in practice, it is possible to carry out air injection at a point when sludge adhesion is not yet sufficient, or in some cases, at the start of purification treatment. After examining this relationship, it was confirmed that stable and efficient purification can be achieved even by continuous injection from the start of purification treatment. In other words, at the start of the purification process, sufficient space is maintained between the fibers, so even if the same amount of air is blown, the exfoliation effect of the blown air is relatively weak; on the other hand, the above-mentioned microorganisms are Since it is a living organism, it has resistance to peeling action against the flow of air and raw water, and it seems to be strengthened by blowing from the start, and stable adhesion and growth can be achieved under moderate air blowing conditions. can. By continuously blowing air from the start of the purification process, there is no need to take special consideration to determine the timing of air blowing intermittently. This makes it possible to carry out stable operations that avoid the interfering effects of anaerobic microorganisms.

A specific example of operation according to the present invention will be described below.

Operation example 1 (Example of a Western confectionery manufacturing factory) BOD is 1800 to 3200 ppm (average approx. 240 ppm)
0ppm), SS is 500-3000ppm (average 11
38 ppm), N-hexane 100-300 ppm (average 201 ppm), p)I 3.5-5.0 (average 4
．． The results of treating the confectionery factory wastewater in 1) are summarized at each multiplication rate as shown in Table 1 below. Figure 5 shows the removal rate in this case as a graph. Figure 1 is simplified and shown in the upper part of Figure 5, that is, the screen (4), the adjustment tank (3), and the contact treatment mechanism (1).
and a settling tank (6). The contact treatment mechanism (1) used was a tank with a volume of 4.5 m, in which vinylidene chloride fibers with a diameter of 2 m and a diameter of 0.8 mm were placed with a porosity of 95.6%.
24 rotary disks (11) each having a thickness of about 5 cm were arranged in parallel and processed while rotating at a circumferential speed of about 20 m/min. The amount of raw water supplied to the contact treatment mechanism (1) is 3 to 5
ff1″/hr (average 3.5m3/hr).

That is, the BOD removal rate gradually improved until about 3 weeks after the start of treatment operation, reaching 91%, but then gradually decreased, and by the 11th week, this BOD removal rate was 68% and 70%.
%, so the air blowing mechanism (10) was used to blow air at a rate of 0.2 mj/l1 inch for about 15 minutes to remove the excessively adhered sludge from the surface layer, resulting in a removal rate of 88%. I have recovered.

Continue operation in this state, and in the 15th week, the removal rate will be 70 again.
%, so when 0.2m'/11in of air was similarly blown for 20 minutes, the removal rate recovered to 85%.
Furthermore, the removal rate decreased to 66% at the 21'a'th point, so it was 0.2
When air was blown at m''/1 lin for 30 minutes, the removal rate recovered to 83%.

In addition, the removal rate decreased to 55% in the 29th week, so from then on, we continued to blow air at a rate of 0.1 to 0.15m3/l5in, and after the 30th week, the removal rate decreased to over 80%. could ensure a high removal rate of 87-89%, which is an excellent performance corresponding to a high removal rate during the initial 3-8 weeks of operation.

Operation example 2 Meat center (and place) example BOD 1100-1600pps+ (average 1358pp
m), SS is 500 to 1300 ppm (average 795
ppm), N-hexane is 200-500 ppm (
The results of treating slaughterhouse wastewater with an average of 296 ppm) and a PLL of 6.5 to 6.8 (average 6.7) are summarized at each multiplication as shown in Table 2 below. A diagram of this is shown in FIG. 6, and the equipment is the same as that in FIG. 5 except that two contact treatment mechanisms (1) and an aeration tank (5) are used.

Raw water supply rate is 6 to 9.5 m'/hr (average 8 m')
/hr), and the other operating conditions were substantially the same as in Operation Example 1.

In other words, in this case, the BOD removal rate decreased to 70% in 10 weeks after the start of operation, so 0.2 m''
When air was blown for 15 minutes at a speed of /min, the analysis value recovered to 90% or more after 3 days.

However, in this case, although the BOD removal rate decreased to 60% at the 148th step, when we continued the operation without air blowing as a trial, we found that the BOD removal rate was 15 i! On the 2nd day of 1, an abnormal odor was noticed, and then the sludge turned black.
2. Adhesive sludge. A severe fallout occurred.

Therefore, as a restoration measure after falling off, high-pressure industrial water is used to completely remove the remaining anaerobic sludge (black), and after a few days, new wastewater is supplied and 0.1~ When the operation was carried out by continuously supplying air at 0.15 m'/n+in, the removal rate gradually improved, with a removal rate of nearly 80% for the 17-week daily removal rate and 90% for the 19-week daily removal rate.
It is possible to continue operation with a high removal rate of over %,
This high removal rate could be completely maintained even after 50 weeks.

Operation example 3 (noodle making and rice factory) BOD: 22QO ~ 3000ppm (average 2465
ppm), SS: 1500-2500ppm (average 1985ppn+), N-hexane: 30-50ppm (
average 30.5 ppm), pH: 3.1-7.0 (
The results of treating wastewater from a noodle and rice factory with an average of 4.4) are summarized at each multiplier as shown in Table 3 below.
A diagram of this is shown in FIG. 7, and the equipment is the same as Operation Example 2.

Raw water supply rate is 6.5-8 r11″/hr, average 7
m'/hr, and other operating conditions were carried out almost in accordance with Operation Example 1.

That is, in this operation example, B
The OD removal rate decreased to 56%, and on the 2nd day of the same week, an abnormal odor occurred, followed by blackening of the sludge and rapid falling off of the adhered sludge. Therefore, as a restoration measure after such falling, the remaining anaerobic sludge (black) was completely removed using high-pressure industrial water, and when operations were restarted, the BOD
The removal rate was 46%, which exceeded the initial 36%, indicating a reasonable improvement in the removal rate.

Furthermore, the BOD removal rate suddenly decreased to 39% on the 13th week, so when air was blown at 0.2 m''/n+in for 30 minutes, the removal rate recovered to 73% the next week.

However, the removal rate decreased to 58% on the 16th day of the week, and after that, the removal rate was continuously increased from 0.15 to 0.2 in this operation.
When air was blown at a rate of 310 m+in, the removal rate improved, and the operation was able to be stably continued for more than 50 weeks with a high removal rate of 80% from the next week onwards.

Operation example 4 (in the case of a noodle factory) BOD: 1300 to 2000 ppm (average 1847
ppm), SS: 300-11000pp (average 7
70ppm), N hexane: 30-50ppm (average 35.9ppm), pH: 3.1-7.0
Table 4 below summarizes the noodle factory wastewater (average 3.3) for each multiplier, and Figure 8 shows this as a diagram. This is the same as Operation Example 1.

The amount of raw water supplied was 4 m3/hr, and the other operating conditions were similar to Operation Example 1.

That is, in this operation example, 0.1 to 0.0 from the beginning of operation.
When air was blown continuously at a rate of 15n+3/hr, the BOD removal rate improved, and from the 4th week onwards, it was possible to continue operating with a high removal rate of 90%. It was confirmed that stable and efficient operation could be achieved even after several weeks.

"Effects of the Invention" According to the present invention as explained above, the synthetic resin fiber material is fastened in a relaxed state and has a large surface area and 9
Using a synthetic fiber rotary disk with a high porosity of 5% or more, BOD is 11,000p due to highly efficient microbial growth.
Exceeding p, and several hundred ppm+ to 100 ppm for SS content as well.
Stable and economical cleaning with a high removal rate of at least 80% for at least one year, even for highly concentrated wastewater exceeding 0ρpo+, and several years or more for boat fishing. This invention enables processing to be carried out smoothly and has great industrial effects.

[BRIEF DESCRIPTION OF THE DRAWINGS] The drawings show the technical contents of the present invention, and FIG. Figure 3 is a partially cutaway slope view of the contact mechanism, Figure 3 is a slope view of the material plate, Figure 4 is a side view partially showing the mounting relationship of the rotary disk, Figure 5
The figure is a diagram summarizing the implementation results of Operation Example 1 in the present invention, and FIGS. 6 to 8 are diagrams summarizing the implementation results of Operation Examples 2 to 4, respectively. In Figures 1 to 8, explanatory diagrams of specifically adopted equipment are also shown. However, in these drawings, (1) is a contact processing mechanism,
(2) is a raw water pit, (3) is an adjustment tank, (4) is a screen, (5) is an aeration tank, (6) is a sedimentation tank, (7) is a treated water tank, (8) is a disinfection tank, (9) ) is the sludge digestion tank, (lO)
is an air blowing mechanism, (11) is a synthetic fiber rotary disk, (lla
) is the material plate, (1l b) is its insertion hole, (12)
is the spacing member, (13) is the tightening rod, (14) is the machine frame, (1
5) (15a) is the flattened welded part, (16) is the end plate, (17
) is the driving mechanism, (19) is the shaft rod, (20) is the shaft cylinder part, is the shaft cylinder part, is the flange part, is the butterfly part, and is the female thread part. Patent applicant Kyokusui Planning Co., Ltd. Inventor Hiromi Iketomo! lr,,'mii'ri7! Part ■

Claims (1)

[Claims] 1. A synthetic fiber rotary disk made of synthetic fibers with a diameter of 0.5 to 1.2 mm intertwined irregularly and compression molded to have a porosity of 85 to 99% was partially immersed in organic wastewater. The organic wastewater is rotated in a state in which the organic wastewater is brought into contact with air alternately, and aerobic microorganisms are allowed to adhere to and proliferate on the surface of the fibers to purify the organic wastewater as described above, and then the wastewater is subjected to sedimentation treatment and discharged. , Organic wastewater with a BOD concentration of 800 ppm or more was supplied to the contact treatment using the synthetic fiber rotary disk described above, and during the contact treatment, air was supplied to the synthetic fiber rotary disk portion to cause the synthetic fibers to adhere to the surface of the synthetic fibers. An organic wastewater treatment method characterized by controlling the sludge film thickness using aerobic microorganisms. 2. A claim in which the contact treatment is started without supplying air to the synthetic fiber rotating disk portion, and the sludge film thickness control by supplying air is started after a sludge film of a predetermined thickness is formed by aerobic microorganisms on the synthetic fiber surface. 1. The organic wastewater treatment method described in 1. 3. The organic wastewater treatment method according to claim 1, wherein the contact treatment is carried out while supplying air substantially at the same time as the start of the contact treatment and controlling the sludge film. 4. BOD concentration in organic wastewater is 1000-100
The organic wastewater treatment method according to claim 1, wherein the organic wastewater treatment method is 00 ppm. 5. The organic wastewater treatment method according to claim 1, wherein organic wastewater having an SS of 300 to 5000 ppm is supplied and treated. 6. When the sludge that adheres to the fiber material turns black and suddenly falls off, the remaining anaerobic sludge is completely removed using high-pressure water, and air is continuously blown in as appropriate to restart the operation. 1. The organic wastewater treatment method described in 1.