JP3400953B2 - Method for regenerating microflora and enhancing physical strength in activated sludge treatment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for regenerating microbial flora in an aeration tank which has caused a decrease in the removal rate of BOD and COD components in aerobic activated sludge treatment, and a method for enhancing physical strength, that is, activated sludge. The present invention relates to a method of regenerating microbial flora in treatment and enhancing physical strength.

[0002]

2. Description of the Related Art Wastewater discharged from various manufacturing plants is generally purified by treatment of activated sludge with aerobic microflora. However, if the quality of the wastewater discharged from the manufacturing process is almost constant, stable treatment is possible, but sometimes the concentration of various pollutant components in the wastewater fluctuates rapidly or the pH fluctuates rapidly. If it is generated or a large amount of oil and fat is mixed, it will damage the microflora inhabiting the aeration tank of the activated sludge treatment device and controlling the purification treatment of pollutants, and the treatment capacity will gradually decrease, that is, the BOD.
In addition, the removal rate of COD components decreases.

[0003] Above all, when a large amount of oil and fat is mixed, the problem is serious, and the surface of the aeration tank is covered with a sticky oil film, and the amount of dissolved oxygen in the tank is lowered, and gradually anaerobic. The state will also kill the microflora.

However, if the damage to the microbial flora in such an aeration tank is slight, it can be recovered by the autonomy and resistance of the microbial flora. When the physical strength of the body itself is weakened, it cannot be recovered, the state of the microflora also changes, and the days when the removal rates of BOD and COD components decrease will continue.

Generally, such a state in which the ability of activated sludge treatment is lowered, that is, a state in which the removal rate of BOD and COD components is lowered is called a bulking state. Due to changes in condition, it is extremely difficult to recover overnight, and recovery can take weeks or even months.

[0006] When such a situation occurs, it is usually necessary to first reduce the inflow of raw wastewater introduced into the aeration tank to reduce the load of pollutants, but immediately
It is not easy to stop the operation of the plant even partially, and the microbial flora in the aeration tank will be forced to undergo severe treatment, and the condition will continue to worsen. There are many.

Various preventive measures against the occurrence of such a bulking state and countermeasures against the occurrence of such a bulking condition have been considered so far. For example, as a preventive measure, if there is a sudden change in the concentration of various pollutants or a sudden change in pH, install a sensor and an alarm at the site before the raw wastewater is introduced into the aeration tank. By configuring to issue an alarm based on the detection signal from the sensor, the administrator who receives this can manually or automatically change the flow of raw wastewater and evacuate to another pit by bypass. is there.

Further, with respect to the mixture of oil and fat, various oil traps are provided and removed before the introduction into the aeration tank. Further, for strengthening the physical strength of the microflora, measures such as daily addition of appropriate amounts of nitrogen and phosphorus as nutrients for microorganisms to the aeration tank have been adopted.

On the other hand, as a countermeasure against the occurrence of the bulking state, as described above, the inflowing pollution load is reduced, air is sufficiently sent to secure the amount of dissolved oxygen, and an appropriate amount as a nutrient is provided. Add nitrogen and phosphorus and wait for the recovery of the aerobic microflora, or empty the aeration tank and add new seed sludge to allow the microbiota to acclimate over time. Etc. are adopted.

However, once the bulking state is reached, the microbial flora in the aeration tank is regenerated, and the generated raw wastewater is expeditedly treated and discharged below the emission standard value. Or, as a company, it is necessary to take immediate action to stop the production of the factory so as not to produce wastewater, which is a very big problem.

[0011]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned disadvantages of the conventional examples and changes the state of the microbial flora of the aeration tank in the treatment of aerobic activated sludge, thereby removing the BOD and COD components. When a decrease in the number of times occurs continuously, it is possible to promptly regenerate the healthy microflora of the aeration tank,
And to provide a method for regenerating microbial flora and strengthening physical strength in an inexpensive and activated sludge treatment, which can be a strong microbial flora that does not lose its balance even when subjected to a rapid pollution load. This is a problem to be solved.

[0012]

[Means for Solving the Problems] 1 of the present invention is mainly composed of aerobic bacteria in an aeration tank of an activated sludge treatment device which has caused a decrease in the removal rate of BOD and COD components. Also, a biosymbiotic bacterium coexisting with a small amount of anaerobic bacterium is added and stirred and aerated to regenerate the microbial flora in the aeration tank and enhance the stamina of the microbial flora. Is the way.

Therefore, according to the method for regenerating the microbial flora and enhancing the physical strength of the activated sludge process according to the first aspect of the present invention, as described above, B
Even in a situation where the removal rate of OD and COD components is reduced, the raw wastewater can be treated while continuing the normal operation without reducing or stopping the introduction amount of the raw wastewater, and the aeration can be performed. The microbial flora in the tank can be regenerated to a healthy state inexpensively and safely without trouble in a short period of time, and the activated sludge treatment can be returned to normal.

In a situation where the inside of the aeration tank is in an anaerobic state or a pseudo-anaerobic state and the organic matter in the introduced raw wastewater is wrapped with something like a glue, According to the observation of the inventor, even if aerobic bacteria are introduced and subjected to aeration treatment, almost no organic matter wrapped with the collagen is decomposed by the aerobic bacteria, and the treated wastewater simply moves in the tank. It will only move with the flow of water, and will eventually settle and accumulate in the lower part of the tank where the flow is poor.

However, when the aerobic bacterium and the biosymbiotic bacterium in which the aerobic bacterium and the anaerobic bacterium coexist are introduced into the tank in the above-mentioned situation, the organic matter encapsulated in the collagen is decomposed. Has started, good decomposition activities continued, and BO
The removal rate of the D and COD components can be restored to the required level.

This is because, when the symbiotic bacterium is put into the tank in the above situation, first, the anaerobic bacterium and the facultative anaerobic bacterium in the symbiotic bacterium act to act as a gelatinous substance that wraps the organic matter. Along with breaking the membrane, the decomposition of organic substances inside is started, and aerobic bacteria subsequently act to further promote the decomposition of organic substances.
It can be presumed that this is because the activated sludge will be returned to normal.

The second aspect of the present invention is the method for regenerating microbial flora and enhancing the physical strength of the activated sludge treatment of the first aspect of the present invention, wherein the aerobic bacterium is 60 to 80% and the facultative anaerobic bacterium is 20 as the biosymbiotic bacterium.
A bacterium group having a composition ratio of -10% and anaerobic bacterium 20 to 10% is adopted.

Therefore, according to the method 2 of the present invention for regenerating the microbial flora and enhancing the physical strength of the activated sludge treatment, as described above, B
Since the ratio of aerobic bacteria, facultative anaerobic bacteria and anaerobic bacteria groups in the bacterial groups to be put into the aeration tank of the activated sludge treatment device that has caused a reduction in the removal rate of OD and COD components becomes appropriate Therefore, the process of decomposing the organic matter described in regard to the first aspect of the present invention can be favorably performed. This percentage is the result of repeated experiments,
Outside the above range, good results cannot be obtained. For example, if the amount of aerobic bacteria is less than the above-mentioned minimum ratio or more than the maximum ratio, good results cannot be obtained. For anaerobic bacteria and facultative anaerobic bacteria, good results cannot be obtained if the combined ratio of both is larger than the maximum ratio or smaller than the minimum ratio.

A third aspect of the present invention is the method for regenerating microbial flora for treatment of activated sludge and enhancing the physical strength according to the first aspect of the present invention, when the temperature of the raw waste water introduced as the biosymbiotic bacteria is 25 to 35 ° C. Decided to mainly adopt mesophilic bacteria that are active in this temperature range and, when the temperature of the raw wastewater to be introduced is 25 ° C or lower, mainly use low temperature bacteria that are active in this temperature range. It is a thing.

Therefore, according to the method 3 of the present invention for regenerating the microbial flora for the treatment of activated sludge and enhancing the physical strength thereof, the bacteria belonging to each of the aerobic bacteria, facultative anaerobic bacteria and anaerobic bacteria are introduced. The temperature of the raw wastewater that corresponds to the temperature of the raw wastewater is adjusted so that it can be activated actively in that temperature range, so that the decomposition activity of organic substances can be performed more efficiently, resulting in speedy regeneration of microbial flora and enhancement of physical strength. Is what you can get.

The fourth aspect of the present invention is, in the method for regenerating a microbial flora for treatment of activated sludge and for enhancing the physical strength of the first aspect of the present invention, as the symbiotic bacterium, a microbial concentration corresponding to the concentration of the substrate of the raw wastewater is added. I decided to do it.

Therefore, according to the method 4 for regenerating the microbial flora of the activated sludge treatment and enhancing the physical strength of the present invention, the bacterial concentration is adjusted according to the substrate concentration of the raw wastewater. Since it was decided to add the necessary amount of the symbiotic bacterium without increasing the amount of the above, it is not necessary to increase the substance requiring decomposition in the wastewater to be treated.

The above-mentioned symbiotic bacterium is used by being adsorbed and immobilized on a carrier, but when the concentration of the substrate is high, for example, when the concentration of protein, carbohydrate, fat, nitrogen content, phosphorus content, etc. is high, It will also be necessary to increase the proportion of symbiotic bacteria to be input. However, simply increasing the input amount causes a problem that the input amount of carriers also increases at the same time. That is, the carrier also needs to be disassembled, and needless to say, this will increase more than necessary.
Not preferable. Therefore, the titer of the symbiotic bacterium, that is, the concentration of the symbiotic bacterium, is used by adsorbing and fixing it on the carrier as a substance corresponding to the concentration of the substrate, and by doing so, unnecessary unnecessary decomposition products are not increased. The activated sludge can be treated very efficiently.

The fifth aspect of the present invention is the method for regenerating the microbial flora of the activated sludge treatment and enhancing the physical strength of the first aspect of the present invention, wherein, as the above-mentioned symbiotic bacteria, yeasts mainly composed of aerobic bacteria, ascomycetes and cellulose decomposition. Bacteria, proteolytic bacteria mainly composed of facultative anaerobic bacteria, lactic acid bacteria and Bacillus subtilis, and photosynthetic bacteria mainly composed of anaerobic bacteria, nitrogen-fixing bacteria, acetic acid bacteria and butyric acid bacteria as carriers, This is a method that employs a complex microbial bacterium that is adsorbed and fixed to coexist, and cultivated at a bacterium concentration corresponding to the substrate concentration of the raw wastewater to which it is applied.

According to the method 5 for regenerating the microbial flora of the activated sludge treatment and enhancing the physical strength of the present invention, a group of aerobic bacteria, facultative anaerobic bacteria and anaerobic bacteria necessary for constituting a symbiotic bacterium. Since the above-mentioned various bacterial groups were selected, as described above, by introducing them into the aeration tank in the situation where the removal rate of BOD and COD components was lowered, the anaerobic bacteria and facultative bacteria The effects of anaerobic bacteria and aerobic bacteria, that is, the decomposition of organic substances encapsulated in the collagen and the subsequent oxidative decomposition of organic substances can be efficiently performed, and as a result, the removal of BOD and COD components The rate can be quickly recovered to the required level.

When a symbiotic bacterium composed of the above-mentioned bacterial group is adopted, no odorous gas is generated in the decomposition of organic matter and the organic matter is efficiently decomposed into carbon dioxide and water. The generation of sewage is extremely small, and the load of sludge treatment is reduced.

Furthermore, the biosymbiotic bacteria composed of the above-mentioned bacterial groups can ensure safety, and when they are put into the aeration tank and the activity is started, new biosymbiotic bacteria are formed in the aeration tank. Since biosynthesis is carried out, the microflora of the aeration tank is in a good state of being resistant to fluctuations in the raw wastewater.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below. INDUSTRIAL APPLICABILITY The method for regenerating microbial flora and enhancing the physical strength of the activated sludge process of the present invention can be applied to the aeration tank in the existing aerobic activated sludge process.

The target activated sludge treatment here is generally known and does not seem to require any particular explanation. However, for the sake of convenience, only the essential points will be described below.
The treatment equipment includes a raw water tank for introducing raw wastewater, an aeration tank for aerating the raw wastewater, a settling tank for settling and separating sludge generated by aeration, a discharge tank for storing the supernatant of the settling tank, and sludge settling in the settling tank. It is a series of equipment including a sludge tank that stores sludge, a sludge dehydrator that dehydrates the water content of the sludge as an auxiliary device that processes the sludge, and an incinerator that incinerates the dehydrated sludge.

The capacity of the pit of the aeration tank is determined by the amount of raw wastewater generated and the required aeration processing time in the aeration tank. Normally, the raw wastewater is 4 to 6 in the tank.
It is designed to be processed for a long period of time.

Further, in the aeration tank, a stirring device for stirring the raw wastewater, a device for feeding air such as a diffuser pipe for supplying dissolved oxygen to the raw wastewater in the tank, a water meter necessary for operation management, and dissolved oxygen. A meter, pH meter and thermometer are attached.

Purification of pollutants in wastewater by treatment with activated sludge is mainly to treat organic substances in wastewater, that is, BOD components, by treating them with microorganisms. It is important to adjust the environment, and it is especially necessary to operate within a certain range of temperature, pH, dissolved oxygen content, nitrogen and phosphorus content of nutrient sources, and various pollution loads.

However, raw wastewater discharged from a wastewater generation source such as a factory is rarely always discharged with a constant water quality, and occasionally, for example, when trouble occurs in the manufacturing process or at regular intervals. At the time of repair, etc., the amount of various pollutants will increase, the pH will change rapidly, the BOD and COD components will increase rapidly, and the oil content will increase rapidly. It may deviate significantly from driving.

In such a state, it is necessary to take a measure such as detecting an abnormality with a sensor and temporarily bypassing the raw wastewater and introducing it into another pit. In a place where there is no pit for temporary storage, in order to continue processing without help,
The microflora in the aeration tank will be greatly damaged, and as a result, the removal rate of BOD and COD components will continue to decrease.

When such a state occurs, as described above, the inflow amount of the raw waste water introduced into the aeration tank is reduced early to reduce the load amount of the pollutants, and the amount of dissolved oxygen is reduced. Therefore, it is necessary to provide a nutrient such as nitrogen or phosphorus to cure the nutrient.

However, in a factory that does not have a bypass facility for use under such a situation, the operation of the factory cannot be partially stopped, and the microflora in the aeration tank is treated more and more severely. As a result, the condition of the aeration tank continues to deteriorate, and many filamentous fungi are found in the aeration tank, gradually becoming anaerobic and the hue of the aeration tank also changes, resulting in the bulking state. It becomes.

In the present invention, when such a phenomenon of a deterioration tendency begins to appear in the aeration tank, aerobic bacteria are mainly contained in the aeration tank, and facultative anaerobic bacteria and some anaerobic bacteria are added. The coexisting symbiotic bacteria are added and aerated with stirring, thereby imparting regeneration or recovery of the microflora in the aeration tank and enhancement of the physical strength of the microflora.

Here, the symbiotic bacterium will be described.
The symbiotic bacterium is an aerobic, effective facultative anaerobic and anaerobic bacterial group that is carefully selected from a myriad of microbial groups existing in nature, and is the temperature of the target wastewater. According to the above, for example, if the temperature of the raw waste water is in the range of 25 to 35 ° C., it is selected from mesophilic bacteria, and if the temperature is 25 ° C. or less, it is selected from low temperature bacteria and used.

These bacterial groups are mainly anaerobic, mainly yeasts containing aerobic bacteria, ascomycetes and cellulolytic bacteria, proteolytic bacteria mainly containing facultative anaerobic bacteria, lactic acid bacteria and Bacillus subtilis. It is a group of complex microorganisms that coexist with photosynthetic bacteria including nitrogenous bacteria, nitrogen-fixing bacteria, acetic acid bacteria and butyric acid bacteria.

Further, among these bacterial groups, aerobic bacterial groups are 6
0-80%, facultative anaerobic bacteria group 20-10%,
Those in which the anaerobic bacteria group is contained in about 20 to 10% are effective.

These complex microbial groups are co-cultivated,
As a carrier in that case, for example, brown rice powder, rice bran, bran, a combination of single or plural kinds of zeolite and fiber, protein, corn powder, nitrogen inorganic matter, single or plural kinds of vitamins and minerals It is intended to be adsorbed and fixed to a mixture of a mixture of these, and these bacterial groups are gradually planted in these carriers and co-cultivated while gradually reducing the water content,
Carry in a dormant state. When these dormant bacteria are put into the raw wastewater of the aeration tank, they will immediately resume their activities.

The concentration (titer) of the bacterial group to be adsorbed on the carrier is determined according to the substrate concentration of the raw wastewater to be applied, which is mainly the bacterial stock solution (from inoculum) when planting the bacteria on the carrier. (Obtained by brewing). For example, in the case of using the bacterium stock solution brewed by the present inventor, in the usual case, 10 kg of carrier
On the other hand, the bacteria are planted at a ratio of 700 cc of the stock solution.
On the other hand, when it is necessary to increase the concentration (titer) of the bacterial group, the proportion of the stock solution is increased as necessary. It cannot be said that the bacterial concentration at the time of planting is high when the concentration of the undiluted solution is high when the culture is completed and the water content is lowered to the dormant state, but it generally increases accordingly. .

The standard of the concentration of the bacterial group to be added to the raw wastewater can be determined experimentally. For example, by inoculating a bacterium stock solution brewed under a certain condition in a certain carrier, culturing and fixing the bacterium group under a certain condition into a certain amount of raw wastewater having a certain substrate condition (concentration), and repeating the experiment, The degree of effectiveness of such a bacterial group becomes clear, and this can be used as a reference value for bacterial concentration. In this way, if the standard of the concentration of bacteria that effectively acts on the raw wastewater with a constant substrate concentration is determined, the substrate concentration of the raw wastewater is compared with the above-mentioned constant substrate concentration as the standard, and if it exceeds it, Therefore, the bacterial concentration should be increased accordingly. As described above, the bacterium concentration can be increased by increasing the ratio of the bacterium stock solution to be planted on the carrier.
Can be increased.

Further, this complex microbial group is a bacterium that exists in nature and works effectively for purification, and in any case, a safe microbial group is selected.

The above-mentioned mechanism of purification by the symbiotic bacterium is to find an effective purification action by the action of the microorganism group which is carried out in the natural world, and to carry out this effectively artificially. According to the knowledge of the present inventor, various organic substances are decomposed by repeated oxidation activity by aerobic bacteria and reduction activity by anaerobic bacteria, and in the present invention, they are included in the above-mentioned symbiotic bacteria. The aerobic, facultative and anaerobic, and anaerobic bacterial groups are responsible for their respective functions of oxidation and reduction, and decompose various organic substances in the target raw wastewater. Furthermore, the biosymbiotic bacterium undergoes new biosynthesis along with such activity,
Proliferation is repeated and a stable purifying action continues.

In order to carry out such an effective activity by the symbiotic bacterium, temperature,
It is necessary that pH, dissolved oxygen content, nutrient balance, trace elements, enzymes, etc. be suitable.

Therefore, in the present invention, as described above, the bacterium to be used is selected depending on the temperature of the target raw wastewater. When the raw wastewater has a low temperature of less than 10 ° C., a psychrophilic bacterium that prefers a low temperature can be adopted among the psychrophilic bacteria.

It is preferable that the pH of the raw wastewater is about 5.5 to 8.5 and the dissolved oxygen amount is about 1 to 1.5 ppm.

On the other hand, as a nutrient salt balance, appropriate amounts of nitrogen and phosphorus salts are required for oxidative decomposition under aerobic conditions. Also, as trace elements, elements such as potassium, sodium, calcium and magnesium are osmotic pressure adjusting action that keeps the in vivo osmotic pressure constant against external environmental changes in the growth and metabolism of microorganisms and catalytic action that activates enzymes. Needed for.

Further, bicarbonates, phosphates and the like are also necessary because they impart a buffering effect for keeping the pH in the body constant. Furthermore, enzymes also play an important role in oxidative degradation of various bacteria under aerobic conditions.

The function of decomposing organic matter by such a symbiotic bacterium does not generate a foul-smelling gas in the process and the organic matter is effectively decomposed into water and carbon dioxide, so that the generation of sludge is extremely small. Has become.

The amount of such a symbiotic bacterium to be added to the aeration tank is 3 to 3 for both carriers with respect to the BOD pollution load amount (kg / day) in the case of culturing by the present inventor as described above. It is suitable to add about 4% daily. Also BO
D When the pollution load is high (the substrate concentration is high), it is preferable to increase the titer (concentration) of the bacterium to be added, as described above, because the influence of the carrier amount is reduced. . Further, even if the recovery of the state of the aeration tank is confirmed, it is necessary to continuously add it for a while, for example, for about a week, in order to strengthen the microbiota.

Next, a method of treatment with a symbiotic bacterium when a decrease in the removal rate of BOD and COD components occurs continuously and an abnormality is observed in the microflora of the aeration tank will be described.

Usually, in the activated sludge treatment, the color, smell and bubbles of the aeration tank are observed by daily patrol, and the aeration solution being treated in the aeration tank is collected in a 1-liter graduated cylinder. Let stand for 30 minutes and settle the activated sludge (S
It is important to measure V) to understand the condition of the aeration tank when it is in good condition.

In this way, the change in the state is visually or olfactually compared with the current situation, and the pH, BOD, COD, SS values and BOD, COD of the wastewater before and after the activated sludge treatment,
It is to read the change quickly from the value of the removal rate of SS.

Generally, BOD, COD and SS are measured by
In many cases, the measurement is made about twice a week, but it is preferable to make the measurement every day in order to quickly find the change in the condition of the aeration tank. Usually, when the change from a good condition lasts for 3 days, it should be considered as urgently necessary to be treated if it continues to be for 4 to 5 days or more with caution. If left in this state, it will take a long time to recover the microbial flora in the aeration tank, and in severe cases, the microbial flora may be regenerated from the seed sludge.

In such a case, the pH of the aeration tank is promptly adjusted to 6.0 to 8.0, and the dissolved oxygen content is adjusted to 1 to 1.
5ppm each, while continuing to stir while introducing the raw wastewater, the biosymbiotic bacteria in the aeration tank, a certain ratio to the BOD pollution load of the raw wastewater (kg / day), for example, as described above. As described above, in the case of culturing by the present inventor, the carrier is added so as to be about 3 to 4%.
The above-mentioned symbiotic bacteria are added every day, and even if the condition is restored, 1
It is preferable to continuously add it for about a week to 10 days in order to strengthen the microflora in the aeration tank.

The microbial flora in the aeration tank is gradually recovered by the addition of the above-mentioned symbiotic bacteria, and the BOD, COD, SS values of the treated water and the BOD, COD of the waste water,
The removal rate of SS improves. Further, by adding the above-mentioned symbiotic bacterium, a new symbiotic bacterium is generated in the microbial flora of the aeration tank by biosynthesis, so that the microbial flora gradually becomes resistant and is in a good state.

[0059]

EXAMPLES Next, the present invention will be described in detail with reference to Examples 1 and 2, but this is for explaining the effects of the present invention, and the present invention is not limited thereby. Absent.

<Example 1> The water quality of the raw wastewater (effluent volume 140 m ³ / day) after coagulation and sedimentation treatment in a food processing plant was such that the wastewater temperature was 28 ° C., pH 5.5, BOD 850 ppm, and COD 380 pp.
m, SS 360 ppm, and N-hexane extract 75 ppm were treated by the usual aerobic activated sludge treatment method.

However, the water quality after the activated sludge treatment is BOD 90.
~ 120ppm, COD70 ~ 140ppm, SS70 ~ 1
Since the treatment condition was 40 ppm, which was inferior for 5 days, it was detected as abnormal, and 4.2 kg of bio-symbiotic bacteria of the following composition (bacterial concentration was almost the standard concentration) was added to the aeration tank together with the carrier (BOD pollution load). (3.5% of the amount added), pH was controlled at 6.0-8.0, dissolved oxygen amount was controlled at 1-1.5 ppm, and raw sludge was introduced and activated sludge treatment was performed while stirring and aeration. Continued. Regarding the introduction of the symbiotic bacterium, 4.2 kg of each carrier was continuously introduced every day for 10 days, and the state of the aeration tank was observed and the water quality test after the treatment was conducted.

[Composition of the symbiotic bacterium of Example 1] As aerobic bacteria, yeast, ascomycetes, and cellulolytic bacteria
As a facultative anaerobic bacterium, a proteolytic bacterium, a lactic acid bacterium, and a Bacillus subtilis are selected, and as an anaerobic bacterium, a photosynthetic bacterium, a nitrogen-fixing bacterium, and an acetic acid bacterium are selected.
%, The facultative anaerobic group was 20%, and the anaerobic group was 15%. In each case, a group of bacteria belonging to the mesophilic bacterium was selected.
These bacterial groups were symbioticly cultivated and adsorbed and fixed on a mixture of brown rice flour and bran, protein, corn powder, vitamins and minerals as a carrier.
Prior to the treatment of Example 1, it was confirmed that the above-mentioned symbiotic bacterium was safe by an acute toxicity test using a fish killifish and an oral acute toxicity test using a mouse.

<Example 2> The quality of the raw wastewater (wastewater amount 1270 m ³ / day) of the wool treatment plant was such that the wastewater temperature was 26 ° C and the pH was 8.
4, BOD900ppm, COD300ppm, SS180
The ppm and the N-hexane extract of 90 ppm were treated by the usual aerobic activated sludge treatment method.

However, the water quality after the activated sludge treatment is BOD10.
0-140ppm, COD70-85ppm, SS40-6
Since the treatment condition was 0 ppm and continued to be inferior for 5 days, it was detected as an abnormality and the aeration tank was treated with a symbiotic bacterium with the titer (bacterial concentration) of the bacteria of the following composition increased to about 3 times the normal level. Add 12 kg each (add 3.2% in normal titer to BOD pollution load), control pH to 6.0-8.0 and dissolved oxygen content to 1-1.5 ppm respectively. The activated sludge treatment was continued while introducing waste water and stirring and aerating. Also,
The above-mentioned symbiotic fungus input is 12 kg for each carrier every day.
It was continuously charged for 0 days, and the state of the aeration tank was observed and the water quality test after the treatment was performed.

[Composition of the symbiotic bacterium of Example 2] Among aerobic bacteria, yeast, ascomycetes and cellulolytic bacteria,
As a facultative anaerobic bacterium, proteolytic bacteria, lactic acid bacteria and Bacillus subtilis are selected, and as anaerobic bacteria, photosynthetic bacteria, nitrogen-fixing bacteria and butyric acid bacteria are selected.
%, The facultative anaerobic group was 15%, and the anaerobic group was 15%. In all cases, mesophilic bacteria were selected. Coexisting with these bacterial groups, the amount of the stock solution when planting the bacteria (the one brewed by the present inventor) was added and cultivated at 3 times the reference value described above, and the mixture was cultured as brown rice flour and bran and protein, It was adsorbed and fixed to a mixture of corn powder, vitamins and minerals. In addition, it was confirmed that the above-mentioned symbiotic bacterium was also safe prior to the treatment in Example 2 by an acute toxicity test using a fish killifish and an oral acute toxicity test using a mouse.

In Examples 1 and 2, the water quality data of each raw wastewater, the water quality data before introducing the symbiotic bacterium of the above composition into each aeration tank, and the symbiotic bacterium of the above composition were used. The water quality data 7 days after the injection was measured by the following measurement items and measurement methods, and summarized in Table 1 and Table 2, respectively.

<Measurement Item and Measurement Method> 1. Measurement of Discharged Water A commercially available flow meter is used for measurement. 2. Measurement of pH Measured according to JIS K0102 12.1. 3. BOD measurement It is measured according to JIS K01021. 4. COD measurement It is measured according to JIS K01021. 5. SS measurement S46 Announcement 59 Measure according to Appendix Table 8. 6. Measurement of N-hexane extract substance Measure according to S49 Announcement 64 Appendix 5. 7. Judgment of odor in the aeration tank The odor during operation in the aeration tank is scented and expressed.

[0068]

[Table 1]

As can be seen from the results of the water quality test before and after the addition of the symbiotic bacterium of Example 1 shown in Table 1, the weak rotten odor before the addition of the symbiotic bacterium was slightly sweet and sour peculiar to the activated sludge treatment after the addition. The smell has changed, and you can clearly feel that the condition has improved. Also, looking at the respective values of BOD, COD, and SS before and after the addition of the symbiotic bacterium, the numerical values are decreasing, and it can be seen that there is a clear effect.

[0070]

[Table 2]

As shown in Table 2, the weak rotten odor before the addition of the symbiotic bacterium has changed to a slightly sweet and sour odor peculiar to the activated sludge treatment after the addition, and the state is clearly shown in Example 2. You can feel the improvement. Also, in the water quality test results, BOD before and after the introduction of the symbiotic bacteria,
Looking at the respective values of COD and SS, the numerical values are decreasing, and it can be seen that a clear effect is obtained here as well.

[0072]

As described above, according to the method for regenerating microbial flora and enhancing the physical strength of the activated sludge process of the present invention 1, normal operation can be performed without reducing or stopping the introduction amount of raw wastewater. The raw wastewater can be treated while continuing, and the microbial flora in the aeration tank can be regenerated to a healthy state inexpensively and safely in a short period of time without any trouble, and the activated sludge treatment can be restored to normal. it can.

The inside of the aeration tank is in the anaerobic state or the pseudo-anaerobic state as described above, and a situation occurs in which the organic matter in the raw waste water introduced is wrapped in something like a colloid. If it does, even if it is inside the tank in such a situation, if the aerobic bacterium and the biosymbiotic bacterium in which the anaerobic bacterium is symbiotic are added, the decomposition of the organic matter encapsulated in the collagen is caused. As a result, good decomposition activity will continue, and the removal rates of BOD and COD components can be restored to the required levels.

This is because when the symbiotic bacterium is put into the tank in the above situation, first, the anaerobic bacterium and the facultative anaerobic bacterium in the bacterium act to act on the colloidal membrane wrapping the organic matter. It can be presumed that this is because when the organic sludge is broken, the decomposition of the organic matter in the inside is started, and subsequently the aerobic bacteria act to further promote the decomposition of the organic matter to restore the activated sludge to the normal state.

The second aspect of the present invention is the method for regenerating microbial flora and enhancing the physical strength of the activated sludge process according to the first aspect of the present invention, wherein the aerobic bacterium is 60 to 80%, and the facultative anaerobic bacterium is 20% as the symbiotic bacterium.
A bacterium group having a composition ratio of 10% to 10% and an anaerobic bacterium of 20% to 10% is adopted. Therefore, according to 2 of the present invention, BO
Since the proportion of aerobic bacteria, facultative anaerobic bacteria and anaerobic bacteria groups in the bacterial groups to be put into the aeration tank of the activated sludge treatment device that has caused a decrease in the removal rate of D and COD components becomes appropriate. ,
The process of decomposing organic matter described in relation to 1 of the present invention can be well performed.

The third aspect of the present invention is the method for regenerating the microbial flora of the activated sludge treatment of the first aspect of the present invention, wherein the raw wastewater introduced as the symbiotic bacterium has a temperature of 25 to 35 ° C. Decided to mainly adopt mesophilic bacteria that are active in this temperature range and, when the temperature of the raw wastewater to be introduced is 25 ° C or lower, mainly use low temperature bacteria that are active in this temperature range. Therefore, according to 3 of the present invention, the bacteria belonging to each of the aerobic bacteria, facultative anaerobic bacteria and anaerobic bacteria groups are made to correspond to the temperature of the raw wastewater to be introduced,
Since it is decided to use the one that is active at that temperature, it is possible to more efficiently decompose organic substances and the like, and it is possible to speedily obtain the results of microbial flora regeneration and physical strength enhancement.

The fourth aspect of the present invention is the method for regenerating the microbial flora and enhancing the physical strength of the activated sludge process according to the first aspect, wherein the symbiotic bacterium is added at a microbial concentration corresponding to the concentration of the raw wastewater substrate. Therefore, according to the present invention,
According to, according to the substrate concentration of the raw wastewater, the bacterial concentration is adjusted,
For example, even when the substrate concentration is high, the required amount of the biosymbiotic bacterium is introduced without increasing the amount of the carrier, so that it is not necessary to increase the substance to be decomposed in the wastewater to be treated.

The fifth aspect of the present invention is the method for regenerating the microbial flora of the activated sludge treatment and enhancing the physical strength of the first aspect of the present invention, wherein yeasts, ascomycetes and cellulosics mainly composed of aerobic bacteria are used as the symbiotic bacteria. Bacteria, proteolytic bacteria mainly composed of facultative anaerobic bacteria, lactic acid bacteria and Bacillus subtilis, and photosynthetic bacteria mainly composed of anaerobic bacteria, nitrogen-fixing bacteria, acetic acid bacteria and butyric acid bacteria as carriers, The present invention employs a complex microbial bacterium that is adsorbed, fixed and symbiotic, and cultivated at a bacterium concentration corresponding to the substrate concentration of the target wastewater to be applied. Therefore, according to 5 of the present invention, a symbiotic bacterium is constituted. Since the above-mentioned various bacterial groups were selected among the aerobic bacteria, facultative anaerobic bacteria and anaerobic bacteria necessary for the above, as described above, in the situation in which the removal rate of BOD and COD components was decreased By putting these into the aeration tank, The action of the anaerobic bacterium and the facultative anaerobic bacterium and the action of the aerobic bacterium, that is, the action of the decomposition of the organic substance encapsulated in the collagen by the former and the subsequent oxidative decomposition of the organic substance by the latter can be efficiently performed, As a result, B
The removal rate of the OD and COD components can be quickly recovered to the required level.

When a symbiotic bacterium composed of the above-mentioned group of bacteria is adopted, no odorous gas is generated in the decomposition of organic matter, and the organic matter is efficiently decomposed into carbon dioxide and water. The generation of sewage is extremely small, and the load of sludge treatment is reduced.

Further, the symbiotic bacterium composed of the above-mentioned bacterium group can ensure the safety, and when it is put into the aeration tank and the activity is started, a new symbiotic bacterium is generated in the aeration tank. Since biosynthesis is carried out, the microflora of the aeration tank is in a good state of being resistant to fluctuations in the raw wastewater.

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI C12N 1/00 C12N 1/00 S // (C12N 1/00 C12R 1:01) C12R 1:01 (C12N 1/00 1: 125 C12R 1: 125) C12R 1: 645 (C12N 1/00 C12R 1: 645) (58) Fields investigated (Int.Cl. ⁷ , DB name) C02F 3/12 C02F 3/34

Claims (5)

(57) [Claims] 1. An aeration tank of an activated sludge treatment device, which has caused a reduction in the removal rate of BOD and COD components, is mainly composed of aerobic bacteria, and facultative anaerobic bacteria and some anaerobic bacteria are allowed to coexist therewith. A method for regenerating a microbial flora in an activated sludge process and a method for enhancing a stamina, which comprises introducing a symbiotic bacterium and stirring and aerating to revitalize the microbial fauna in the aeration tank and enhance the stamina of the microflora. 2. An aerobic bacterium 60-as the symbiotic bacterium.
80%, facultative anaerobic bacteria 20 to 10%, anaerobic bacteria 20 to 1
The method for regenerating the microbial flora and enhancing the physical strength of the activated sludge process according to claim 1, wherein a bacterial group having a composition ratio of 0% is adopted. 3. When the temperature of the raw wastewater to be introduced is 25 to 35 ° C., the mesophilic bacterium actively active in this temperature range is mainly used as the biosymbiotic bacterium, and the temperature of the raw wastewater to be introduced is selected. When the temperature is 25 ° C or lower, the method for regenerating microbial flora and enhancing the physical strength of the activated sludge treatment according to claim 1 or 2, wherein psychrophilic bacteria actively active in this temperature range are mainly adopted. 4. The method for regenerating microbial flora and enhancing physical strength of activated sludge treatment according to claim 1, 2 or 3, wherein the symbiotic bacterium is added at a bacterium concentration corresponding to the concentration of a substrate of raw wastewater. . 5. As the symbiotic bacteria, yeasts, ascomycetes, and cellulolytic bacteria mainly composed of aerobic bacteria, proteolytic bacteria, lactic acid bacteria and Bacillus subtilis mainly composed of facultative anaerobic bacteria, and anaerobic A complex consisting of photosynthetic bacteria mainly consisting of bacteria, nitrogen-fixing bacteria, acetic acid bacteria and butyric acid bacteria, which are adsorbed and fixed on a carrier to coexist, and cultured at a bacterial concentration corresponding to the substrate concentration of the raw wastewater to be applied. The method for regenerating the microbial flora and enhancing the physical strength of the activated sludge treatment according to claim 1, 2 or 3 employing a microbial bacterium.