CN1326786C - Method and device for treating organic wastewater - Google Patents

Abstract

The present invention relates to a method and an apparatus for treating sewage, feces and urine, and organic wastewater discharged from a production process of a food factory or a chemical factory by biological digestion, and an object of the present invention is to provide a method and an apparatus for treating organic wastewater which can significantly reduce the amount of excess sludge discharged to the outside of a treatment system and which can contain a small amount of nitrogen-containing organic components or nitrogen-containing inorganic components in treated water discharged to the outside of the treatment system. The method for treating organic wastewater according to the present invention is characterized in that sludge produced by nitrification and denitrification after the nitrification and denitrification of organic wastewater is solubilized. The method for treating organic wastewater according to the present invention is characterized by comprising: an apparatus for nitrification and denitrification of organic wastewater and an apparatus for solubilizing sludge produced by nitrification and denitrification.

Description

Method and device for treating organic wastewater

technical field

The invention relates to a method and a device for treating waste water containing organic substances, such as sewage, excrement, organic waste water discharged from the manufacturing process of food factories, chemical factories, etc., by biological treatment methods.

Background technique

Conventionally, as a treatment method for such organic wastewater, a method of biologically digesting organic components in organic sludge by an aerobic treatment method called an activated sludge method, an anaerobic methane digestion method, etc. has been used. Aerobic or anaerobic microorganisms. In the method, for the excess sludge composed of microbial biomass and untreated residual sludge formed by biological digestion while converting organic matter into gas components such as carbon dioxide and biogas, solidification is carried out with a sedimentation tank or the like on the one hand. The liquid component is separated to properly dispose of the treatment liquid, and on the other hand, the excess sludge is usually disposed of by sea disposal and landfill.

However, ocean dumping also involves environmental damage, so it is in the trend of being banned recently when the call for global environmental protection is getting higher and higher. In addition, in landfill, it becomes difficult year by year to secure a landfill disposal site.

Therefore, the applicant of the present patent applied for an invention patent described in Japanese Patent Application Laid-Open No. 9-10791 as a method for reducing the amount of excess sludge generated by biologically treating organic wastewater.

Said invention is that after the organic waste water sent from the organic waste water storage device is treated aerobically with an aeration device, the waste water is separated into solid and liquid parts into treated water and sludge in a solid-liquid part separation device, and the A part of the sludge separated in the solid-liquid separation device is sent back to the aeration device, and then the remaining sludge of the separated sludge is exchanged in the solid-liquid separation device using a heat exchanger, and then the solubilization device is used at a high temperature The method of solubilizing and returning the solubilized treated water to the aeration device.

However, in general, the sludge produced by the biological treatment method contains protein, so there are nitrogen compounds such as ammonia in the wastewater returned from the solubilization device to the aeration device along with the treated water discharged from the solid-liquid separation device The problem of being discharged to the outside together. In addition, because the sludge produced by the biological treatment method generally contains phosphorus components, there are also phosphorus compounds in the wastewater discharged from the solubilization device to the aeration device together with the treated water discharged from the solid-liquid separation device. external problems.

Contents of the invention

The present invention is made to solve such problems, and the purpose is to provide a method and device for treating organic wastewater, which can greatly reduce the amount of excess sludge discharged to the outside of the treatment system, and can reduce the amount of sludge discharged to Nitrogen-containing organic components or nitrogen-containing inorganic components in the treated water outside the treatment system.

The present invention is a method for treating organic wastewater with a biological method. In order to achieve this purpose, after nitrification and denitrification treatment of organic wastewater, organic wastewater that can dissolve the sludge produced by nitrification and denitrification treatment is provided. Approach.

In addition, the present invention provides a device for treating organic waste water with a biological method, and provides a method for treating organic waste water, which is equipped with a device for nitrification and denitrification of organic waste water, and for the sludge produced by nitrification and denitrification. Solubilizing solubilizing tank.

Like this, in the present invention, after carrying out nitrification and denitrification treatment to organic waste water, solubilization treatment is carried out to the sludge produced by nitrification and denitrification treatment, therefore, can reduce the sludge that nitrification and denitrification treatment produce, thereby, It has the effect of significantly reducing nitrogen-containing organic components or nitrogen-containing inorganic components in the treated water discharged out of the treatment system than before.

The nitrification and denitrification treatment of organic wastewater is performed batchwise in a reaction tank, for example.

Nitrification in this case is carried out, for example, by aeration, and denitrification takes place by stopping the aeration. Preferably, the solubilization treatment liquid is returned to the reaction tank 30 minutes to 3 hours before the aeration is stopped, more preferably, the return is carried out 30 minutes to 1 hour before.

When the nitrification process of nitrification and denitrification treatment by aeration is carried out intermittently in this way, and the solubilization treatment liquid is returned to the reaction tank before the specified time of stopping the aeration, the solubilization treatment liquid can be contained in the solubilization treatment. The organic matter in the sludge is effectively used as a proton source (BOD source) during denitrification treatment, and can promote denitrification. Therefore, since the amount of chemicals such as methanol generally used as a proton source can be reduced, there is an effect that costs associated with the amount of the drugs can be reduced.

In addition, other methods of nitrification and denitrification treatment of organic wastewater are performed through an anaerobic treatment process, a primary aeration process, a denitrification process in an anaerobic tank, and a secondary aeration process. In this case, the sludge from which the solid and liquid components were separated after the secondary aeration process is subjected to solubilization treatment.

Furthermore, other methods of nitrification and denitrification treatment of organic wastewater are denitrification process in anaerobic tank, anaerobic treatment process, treatment process in exchange tank, denitrification process in anaerobic tank, exposure gas process. In this case, the sludge from which solid and liquid components have been separated after the aeration process is subjected to solubilization treatment. In addition, nitrification is carried out in the aeration process, and the nitrification liquid after nitrification will be returned to the denitrification process.

Furthermore, other forms of nitrification and denitrification treatment of organic wastewater are carried out by anaerobic treatment process, denitrification process in anaerobic tank, aeration process, and by reducing the amount of water dissolved in the solubilization treatment. oxygen in the water. In this case, nitrification also takes place in the aeration process. The nitrification liquid after nitrification will be returned to the denitrification process.

Furthermore, other methods of nitrification and denitrification treatment of organic wastewater are performed by an anaerobic treatment process, a denitrification process in an anaerobic tank, and an aeration process.

As these nitrification and denitrification treatments, in the case of including anaerobic treatment process or aerobic treatment process such as aeration treatment, even if phosphorus content is contained in the sludge generated by nitrification and denitrification treatment, anaerobic treatment can also be used. Phosphorus removal by anaerobic treatment and binding phosphorus by aerobic treatment.

Another object of the present invention is to provide an organic wastewater treatment method and an apparatus thereof capable of reducing phosphorus content in treated water discharged outside the treatment system.

In order to achieve the above-mentioned objects, the present invention provides a method for treating organic wastewater and a device thereof equipped with the above-mentioned device for removing phosphorus in sludge produced by nitrification and denitrification treatment. Furthermore, by providing a phosphorus removal device, there is an effect of suitably preventing phosphorus components from being discharged to the outside of the system.

Description of drawings

FIG. 1 is a schematic block diagram showing an organic wastewater treatment device as one embodiment.

FIG. 2 is a block diagram of a batch processing process performed in the processing apparatus shown in FIG. 1 .

Fig. 3 is a block diagram of another example of batch processing steps performed in the processing apparatus shown in Fig. 1 .

Fig. 4 is a schematic block diagram showing an organic wastewater treatment device in another embodiment.

Fig. 5 is a schematic block diagram showing an organic wastewater treatment device in another embodiment.

Fig. 6 is a schematic block diagram showing an organic wastewater treatment device in another embodiment.

Fig. 7 is a schematic block diagram showing an organic wastewater treatment device in another embodiment.

Fig. 8 is a schematic block diagram showing an organic wastewater treatment device in another embodiment.

Fig. 9 is a schematic block diagram showing an organic wastewater treatment device in another embodiment.

Fig. 10 is a schematic block diagram showing an organic wastewater treatment device in another embodiment.

Fig. 11 is a schematic block diagram showing an organic wastewater treatment device in another embodiment.

Fig. 12 is a schematic block diagram showing an organic wastewater treatment device in another embodiment.

Fig. 13 is a schematic block diagram showing an organic wastewater treatment device in another embodiment.

Fig. 14 is a schematic block diagram showing an organic wastewater treatment device in another embodiment.

Fig. 15 is a schematic block diagram showing an organic wastewater treatment device in another embodiment.

FIG. 16 is a block diagram of a batch-type treatment process performed in the treatment apparatus shown in FIG. 15 .

Fig. 17 is a schematic block diagram showing an organic wastewater treatment device in another embodiment.

Fig. 18 is a schematic block diagram showing an organic wastewater treatment device in another embodiment.

Detailed ways

Embodiments of the present invention will be described below based on the drawings.

(Embodiment 1)

The organic wastewater treatment device of this embodiment is composed of a reaction tank 1 and a dissolving tank 2 as shown in FIG. 1 . The organic waste water is treated intermittently in the reaction tank 1 . Sewage is used in this embodiment as organic waste water of raw water.

In this embodiment, inflow of raw water, reaction, sedimentation, drainage, sludge discharge, etc. are treated as one cycle. More specifically, as shown in Fig. 2, the processes of aeration, agitation, aeration, agitation, aeration, precipitation by aeration stop, solid-liquid separation, and solubilization treatment are circulated in the raw water inflow receiving device to proceed. In this case, aeration is an aerobic treatment and agitation is anaerobic. In the reaction tank 1, the process of repeating aeration and stirring, the process of sedimentation, and the separation of solid and liquid components are performed, and the process of solubilization treatment is performed in the solubilization tank 2. The treatment time of each process can be adjusted, and a series of intermittent treatment of wastewater treatment from the inflow of raw water to the discharge of treated water can be performed several times (for example, 2 to 4 times) in one day, but it can also be performed according to the nature and amount of wastewater, etc. It does not matter if the treatment time of each step is adjusted so that it is performed about once a day, or about twice in three days.

In the present embodiment, nitrification treatment is performed by nitrifying bacteria in the aeration step, and denitrification treatment is performed by denitrification bacteria in the stirring step in which aeration is stopped. Thereafter, the aeration is stopped, and the sludge is precipitated and separated. The above clarified liquid was discharged, a part of the precipitated sludge was stored in the reaction tank 1 for the next batch treatment, and a part of the remaining sludge was supplied to the solubilization tank 2 for solubilization treatment. Preferably, the waste water that has been solubilized in the solubilization tank 2 is returned to the stirring step of the first step as shown in FIG. 2 . Also, preferably, in the nitrification step, in order to maintain the nitrification reaction of the nitrifying bacteria, the pH is set to 7 or more, and it is especially preferable to set the pH to 7.0-8.0. Moreover, it is preferable to set temperature as 15 degreeC - 35 degreeC, and it is more preferable to set it as 25 degreeC - 35 degreeC. Return the solubilized treatment liquid to the reaction tank 1 30 minutes to 3 hours before stopping the aeration in the first step, preferably 30 minutes to 1 hour before stopping. The number of cycles depends on the BOD-SS load of the reaction tank. Generally, it is preferable to operate in the form of nitrification and denitrification with aeration and stirring for 3 to 4 cycles during high load operation (BOD-SS load: 0.2 to 0.4 kgBOD/kgSS·day). In addition, it is preferable to perform nitrification and denitrification treatment by circulating 2 to 3 times during low-load operation (BOD-SS load: 0.03-0.05 kgBOD/kgSS·day).

The solubilization tank 2 is for solubilizing the sludge supplied from the reaction tank 1 as described above, and the solubilization is performed by a solubilizing enzyme such as protease. The soluble enzyme is produced by thermophilic bacteria, such as aerobic thermophilic bacteria of the genus Bacillus . Such aerobic bacteria may be stored in the dissolving tank 2 in advance, contained in the sludge supplied to the dissolving tank 2 in advance, or added separately in the dissolving tank 2 .

As bacteria of the genus Bacillus, Bacillus stearothermophilus, Bacillus thermoleovorans, etc. can be used, preferably, Bacillus SPT2-1 [FERM P-15395], Bacillus (Bacillus)SPT3[FERM P-19226], GeobacillusSPT4[FERM P-08452], GeobacillusSPT5[FERM P-08453], GeobacillusSPT6[FERM P-08454], GeobacillusSPT7[FERM P-08455], etc.

In the dissolving tank 2, the sludge is decomposed by aerobic bacteria in this way, but it can also cooperate with conventionally known methods such as ozonolysis, electrolysis, thermal alkali decomposition, and enzymatic decomposition (for example, adding protease and lipase alone or in combination) , glycosidase, etc.) and other methods to implement.

In the solubilization tank 2, solubilization of anaerobic or aerobic organic sludge is performed under biological high-temperature conditions. In this case, the anaerobic or aerobic microbial inoculum (thermophilic bacteria) used at high temperature is, for example, obtained by culturing microorganisms in conventional anaerobic or aerobic treatment tanks . In addition, the optimum temperature of the dissolving tank 2 is preferably operated at a temperature in the range of 50 to 90° C., but it varies depending on the type of thermophilic bacteria that decompose the The organic solid matter in the sludge of the high-temperature treatment object, for example, when it is a thermophilic bacteria separated from the excess sludge of sewage, it is operated under high-temperature conditions in the range of 55 to 75° C., preferably at At 60 to 70° C., two functions of solubilization reaction by microorganisms (thermophilic bacteria) and physicochemical thermal decomposition due to heat are effectively and fully exhibited at the same time.

In any case, it is preferable to set the temperature range to 50 to 90° C. depending on the type of microorganisms so that both the solubilization reaction by microorganisms (thermophilic bacteria) and the physicochemical thermal decomposition by heat The role can be effectively and fully exerted at the same time. It is preferable to set the temperature in the range of 55 to 70°C, particularly preferably 60 to 65°C, especially when bacteria of the genus Bacillus, which are aerobic thermophilic bacteria, are used. In addition, it is preferable to set the temperature range to 55 to 65°C when Geobacillus, an aerobic thermophilic bacterium, is used.

In addition, the pH is set according to the type of microorganisms, and the pH range is set in the range of 6-9, preferably in the range of 7-8. This is so that the solubilization treatment liquid does not have a bad influence on nitrification or denitrification treatment. Furthermore, it is preferable that the solubilization treatment is performed with aerobic treatment in order to decompose (nitrate) ammonia generated by decomposition of sludge to some extent.

In this embodiment, before stopping the aeration treatment for 30 minutes to 3 hours, preferably before 30 minutes to 1 hour, the solubilized sludge is returned to the first (first) aeration treatment process reaction tank. Thereby, the organic matter contained in the solubilized sludge can be effectively utilized as a proton source (BOD source) at the time of denitrification treatment, and denitrification can be promoted. Therefore, the amount of chemicals such as methanol, which is generally used as a proton source, can be reduced, and therefore the cost associated with the amount of the drugs can be reduced.

Preferably, the solubilization treatment time in this case is 12 to 72 hours, more preferably 18 to 48 hours, especially preferably 20 to 36 hours. In addition, the solubilization treatment time is set according to the combination method of the waste water treatment system for nitrification and denitrification treatment of waste water and sludge solubilization, so it will be described below for each embodiment.

In addition, the solubilization of thermophilic sludge generates ammonia, but the ammonia contained in the solubilized sludge is oxidized to nitrite nitrogen and nitrate nitrogen that can be denitrified in the aeration process. As a result, the denitrification process happens to be completely performed, and harmful nitrogen components are not discharged outside the system.

In the aeration process in this embodiment, the organic matter is retained, and since the step of oxidizing ammonia to nitrous acid and nitric acid is very important, the reaction of returning the solubilized sludge to the first aeration treatment process is set. The timing of the bath and the time of the solubilization treatment are critical.

(Embodiment 2)

This embodiment is the same batch treatment method as the above-mentioned first embodiment, and the treatment device is composed of a reaction tank 1 and a dissolving tank 2, and circulates through aeration, stirring, aeration, stirring, It is the same as that of Embodiment 1 in that aeration, precipitation by aeration stop, separation of solid and liquid components, and solubilization treatment are performed. Therefore, also in this embodiment, the nitrification treatment by the nitrifying bacteria is performed in the aeration step, and the denitrification treatment by the denitrification bacteria is performed in the stirring step in which the aeration is stopped.

However, in the present embodiment, as shown in FIG. 3 , the treated water after the solubilization treatment is returned to the first (first) stirring step, which is different from the case of returning to the aeration step in Embodiment 1 at this point. different.

In this embodiment, the solubilization treatment liquid is returned to the reaction tank 1 in the denitrification process, so the organic matter contained in the solubilization treatment liquid is effectively used as a proton source during the denitrification treatment, thereby promoting denitrification. In this case, it is preferable to oxidize the ammonia to nitrite nitrogen and nitrate nitrogen in the solubilization treatment in order to reduce the ammonia contained in the solubilization treatment. The longer solubilization treatment time is preferably 24 to 72 hours, more preferably 36 to 72 hours.

In particular, in the present embodiment, the organic matter as a proton source is directly returned to the denitrification treatment step, so the amount of commonly used chemicals such as methanol can be reduced, thereby reducing the cost associated with the amount of chemicals. As mentioned above, by combining the nitrification and denitrification treatment of wastewater with the sludge solubilization treatment, or by setting each treatment process optimally at the time of combination, it is possible to significantly reduce the amount of excess sludge generated, It has the effect of maintaining good water quality.

In addition, as microorganisms that produce soluble enzymes that dissolve sludge, it is preferable to use thermophilic bacteria, especially the various Bacillus and Geobacillus bacteria disclosed in Embodiment 1.

In addition, it is desirable to set the temperature during the solubilization treatment to 50-90°C, which is the same as Embodiment 1. Preferably, in the case of using aerobic thermophilic bacteria such as Bacillus, the set temperature range is 55-70°C. °C, more preferably, especially in the range of 60-65 °C. In addition, the pH at the time of the solubilization treatment is set to be in the range of pH 6-9 as in Embodiment 1, preferably in the range of 7-8.

In addition, the temperature, pH, etc. of the nitration step are also the same as those in Embodiment 1.

(Embodiment 3)

The treatment device of organic wastewater in this embodiment, as shown in Figure 4, has: fermentation liquid storage tank 3, anaerobic tank 4, primary aeration tank 5, anaerobic tank 6, secondary aeration tank 7, sedimentation tank 8. And dissolving tank 2. In this embodiment, as the untreated liquid stored in the fermented liquid storage tank 3 , an acidic fermented liquid obtained by decomposing gas (methane fermentation) and fermenting leftover rice discharged from a food factory is used. In addition to the above liquid to be treated, sewage and the like are supplied to the anaerobic tank.

The anaerobic tank 4 has the function of performing anaerobic digestion on the sewage and the acid fermentation liquid supplied from the above-mentioned fermentation liquid storage tank 1. When the returned sludge or the sludge in the acid fermentation liquid contains phosphorus, it is discharged into the sludge. The function of phosphorus in wastewater.

The primary aeration tank 5 is used to perform aerobic biological treatment on the anaerobic treated treatment liquid in the above-mentioned anaerobic tank 4 through aeration and agitation, to oxidize and decompose the organic matter in the anaerobic treated treated water, or to nitrify the influent of ammonia. The key of the primary aeration tank 5 is that it has an aeration device, and its aeration device need not ask too much, such as an air diffusion tube or the like can be used. Preferably, in order to allow aerobic digestion and decomposition, aeration treatment is performed at room temperature with an air flow rate of 0.1 to 0.5 vvm, but treatment may be performed at a higher temperature than the air flow rate depending on the load. The pH of the liquid to be treated is adjusted to, preferably, 5.0-8.0, more preferably, the pH is adjusted to 7.0-8.0.

The anaerobic tank 6 is made for denitrification treatment of the treatment liquid that has been aerobically treated in the above-mentioned primary aeration tank 5 .

The secondary aeration tank 7 is made for aerobic biological treatment of the treatment liquid denitrified in the above-mentioned anaerobic tank 6 . The secondary aeration tank 7 has the same structure as the above-mentioned primary aeration tank 3, and also carries out biological treatment through aeration and stirring. In this case, the secondary aeration tank 7 has two functions of nitrification and BOD removal. Also, although not shown, part of the nitrification liquid as the treatment liquid in the secondary aeration tank 7 is returned to the anaerobic tank 6, where nitric acid or nitrous acid in the nitrification liquid is denitrified.

The settling tank 8 is made for the separation of solid and liquid components from the treatment liquid biologically treated in the above-mentioned secondary aeration tank 7 . The separated liquid part is reused or discharged as a treatment liquid, and a part of the sludge of the separated and precipitated solid part is supplied to the next dissolving tank 2, and the remaining part is returned to the anaerobic tank 4.

Next, an embodiment of a processing method for processing both sewage and leftovers discharged from a food factory will be described with the processing apparatus having the above-mentioned configuration.

First, gas decomposition is performed on leftover rice discharged from food factories. The gas decomposition is performed by methods such as acid fermentation and methane fermentation. A sour fermented liquid is obtained by decomposing such gas, and the sour fermented liquid is stored in the fermentation storage tank 3 . The acid fermentation broth is supplied from the fermentation broth storage tank 3 to the anaerobic tank 4 . In addition, sewage is also supplied to the anaerobic tank 4 .

In addition, the treated water of the anaerobic treatment is supplied to the primary aeration tank 5 in the next step, and the aerobic treatment is performed while performing aeration and stirring. The nitrification treatment is carried out by carrying out the above-mentioned aerobic treatment with aeration and stirring.

Next, the treatment liquid treated in the primary aeration tank 5 is supplied to the anaerobic tank 6 . Then, denitrification treatment is performed in the anaerobic tank 6 .

In addition, the acid fermentation liquid is supplied from the fermentation liquid storage tank 3 to the anaerobic tank 6 . This is to promote denitrification by effectively using the acid fermentation broth as a proton source (BOD source) during denitrification.

The treatment solution denitrified in the anaerobic tank 6 is supplied to the secondary aeration tank 7, and aerobic treatment is performed while performing aeration and stirring. Nitrification is carried out through aeration treatment in the secondary aeration tank 7 to remove BOD.

Next, the treatment liquid aerated in the secondary aeration tank 7 is supplied to the sedimentation tank 8 . Solid-liquid components are separated in the settling tank 8, and the separated liquid components are reused as treatment liquids or discharged, and a part of the separated and precipitated solid part of the sludge is supplied to the dissolving tank 2 , where the sludge is solubilized aerobically by thermophilic bacteria.

In addition, the remaining part of the settled sludge is returned to the anaerobic tank 4 as return sludge.

The sludge solubilised in the solubilising tank 2 is returned to the anaerobic tank 6 for further treatment. Then, the following processes will be repeatedly circulated: denitrification treatment in the anaerobic tank 6; aeration treatment in the secondary aeration tank 7; solid-liquid component separation in the settling tank 8; Melting treatment.

In the present embodiment, the solubilization of sludge is performed using a continuous method instead of the batch treatment as in Embodiment 1 above. However, in the case of using such a continuous method to solubilize sludge, it is possible to and the effective capacity of the reaction tank to obtain HRT. That is, HRT was calculated based on the formula of HRT (hydraulic residence time)=V/Q (V: capacity of reaction tank, Q: amount of inflow water).

Needless to say, in order to achieve the desired degree of solubilization, the volume of the reaction tank can be reduced to shorten the HRT. Thus, the solubilization time is determined according to the HRT, and lengthy solubilization time is avoided.

Preferably, the HRT is selected based on the HRT that produces and secretes the largest amount of thermophilic bacteria. If the HRT is set in this way, the generated and secreted sludge-soluble enzyme can be effectively used for the reaction. Usually, it is preferable that the HRT is set at 12 to 72 hours, and from the viewpoint of oxidizing the ammonia in the solubilized liquid, it is more preferably set at 24 to 72 hours. From both viewpoints of improving the quality of treated water, it is most preferable to set it to 36 to 48 hours.

In addition, the HRT other than the dissolving tank 2 is 0.5 to 1.5 hours in the anaerobic tank 4, 2 to 6 hours in the primary aeration tank 5, 0.5 to 3 hours in the anaerobic tank 6, and 0.5 to 3 hours in the secondary aeration tank 5. 0.5 to 2 hours in the aeration tank 7, preferably 0.5 to 1 hour in the anaerobic tank 4, 3 to 5 hours in the primary aeration tank 5, and 1 to 2 hours in the anaerobic tank 6. hours, 0.5 to 1.5 hours in the secondary aeration tank 7.

In addition, thermophilic bacteria are used as microorganisms that produce soluble enzymes that dissolve sludge, and it is preferable to use the bacteria of the genus Bacillus and the genus Geobacillus disclosed in the first embodiment.

In addition, it is desirable to set the temperature during the solubilization treatment to 50 to 90°C, which is the same as in Embodiment 1. When using aerobic thermophilic bacteria such as Bacillus, it is preferable to set the temperature in the range of 55-70°C, more preferably, especially 60-65°C. In addition, the pH at the time of the solubilization treatment is set to be in the range of pH 6-9 as in Embodiment 1, preferably in the range of 7-8.

In addition, the temperature, pH, etc. of the nitration process similar to Embodiment 1 were set.

(Embodiment 4)

In this embodiment, as shown in FIG. 5 , a concentrator 9 is provided between the sedimentation tank 8 and the dissolving tank 2 , that is, in the passage from the sedimentation tank 8 to the dissolving tank 2 .

In this embodiment, the sludge separated from the sedimentation tank 8 is supplied to the thickener 9 . In the thickener 9, for example, the sludge is thickened by gravity settling. As the concentration method, besides the gravity sedimentation method, a concentration method using flotation concentration, evaporation concentration, membrane concentration, flocculant addition, trommel type concentration, or centrifugal force can also be used. From the viewpoint of improving the sludge solubilization rate of thermophilic bacteria and compacting the solubilization tank, the sludge concentration rate is preferably concentrated to a water content of 99% by weight or less (sludge concentration of 1% by weight or more). The concentrated liquid is supplied to the dissolving tank 2 . However, the sludge concentration at this time is preferably not more than 5% by weight. This is because, if it exceeds 5% by weight, it will be difficult to discharge it with a pump, and air bubbles in the sludge will remarkably increase during aerobic treatment in a dissolving tank.

Anaerobic treatment in the anaerobic tank 4, aeration treatment in the primary aeration tank 5, denitrification treatment in the anaerobic tank 6, aeration treatment in the secondary aeration tank 7, in the sedimentation The separation of solid and liquid components in the tank 8 and the solubilization treatment in the solubilization tank 5 are the same as those in Embodiment 3, and therefore description thereof will be omitted.

In addition, thermophilic bacteria are used as microorganisms that produce soluble enzymes that dissolve sludge, and it is preferable to use the bacteria of the genus Bacillus and the genus Geobacillus disclosed in the first embodiment.

In addition, it is desirable to set the temperature during the solubilization treatment to 50 to 9°C, which is the same as in Embodiment 1. In the case of using aerobic thermophilic bacteria such as Bacillus, it is preferable to set the temperature range to 55-70°C, more preferably, especially 60-65°C. In addition, the pH at the time of the solubilization treatment is set to be in the range of pH 6-9 as in Embodiment 1, preferably in the range of 7-8.

(Embodiment 5)

In this embodiment, as shown in FIG. 6 , a nitrification tank 10 is provided between the dissolving tank 2 and the anaerobic tank 6 , that is, on the passage from the dissolving tank 2 to the anaerobic tank 6 . By providing such a nitrification tank 10, the ammonia contained in the sludge solubilization liquid is converted into nitrous acid or nitric acid.

In addition, in the present embodiment, a part of the sludge is returned from the sedimentation tank 8 to the outside of the anaerobic tank 4 , and the remaining sludge is also supplied to the nitrification tank 10 via the solubilization tank 2 .

The HRT of the dissolving tank in this embodiment is preferably selected according to the HRT when the generation and secretion of sludge-soluble enzymes are the largest, wherein the sludge-soluble enzymes are secreted by thermophilic bacteria. When HRT is set in this way, the generated and secreted sludge-soluble enzyme can be effectively used for reaction. Usually, HRT is set at 12 to 72 hours, but in this embodiment, because there is the nitrification tank 10 in the step after the solubilization tank, it can be used in the state where ammonia remains in the solubilization treatment liquid. The melting treatment solution is injected into the nitrification tank 10. In consideration of the above, it is preferable to set the HRT at 18-48 hours, most preferably at 20-36 hours.

In addition, the operating conditions of the nitrification tank 10 are preferably in the range of pH 7.0 to 8.0 at 25 to 35°C. The ammonia contained in the sludge soluble waste water is oxidized to nitrous acid and nitric acid, and it is necessary to retain the organic matter as a proton source in the denitrification treatment of the next process. Considering the above points, the HRT of the nitrification tank 10, Preferably, 30 minutes to 3 hours.

Anaerobic treatment in anaerobic tank 4, aeration treatment in primary aeration tank 5, denitrification treatment in anaerobic tank 6, aeration treatment in secondary aeration tank 7, solids in sedimentation tank 8 The separation of the liquid components and the solubilization treatment in the solubilization tank 2 are the same as those in Embodiment 3, and therefore description thereof will be omitted.

In addition, thermophilic bacteria are used as microorganisms that produce soluble enzymes that solubilize sludge. In particular, bacteria of the genus Bacillus or bacteria of the genus Geobacillus disclosed in Embodiment 1 are preferably used.

Furthermore, it is desirable that the temperature during the solubilization treatment be set at 50 to 90° C. as in Embodiment 1, and in the case of using an aerobic thermophilic bacterium such as Bacillus, it is preferable to set the temperature in the range of 55-70°C, more preferably, especially 60-65°C. In addition, the pH at the time of the solubilization treatment is set to be in the range of pH 6-9 as in Embodiment 1, preferably in the range of 7-8.

(Embodiment 6)

In this embodiment, two anaerobic tanks are provided, but only one aeration tank is provided, and there is no difference from Embodiments 3 to 5 in this point.

That is, the treatment device of the present embodiment, as shown in FIG. , and dissolving tank 2.

In this embodiment, the raw water flowing into the anaerobic tank 4 is supplied to the exchange tank 12 .

The exchange tank 12 can change the path of returning sludge and treated water (nitrification liquid) from the aeration tank 13 according to the denitrification degree of the inflowing sewage. For example, in summer and other periods when the degree of denitrification is high, it is used as an anaerobic tank to promote the phosphorus removal reaction of the returned sludge; And the denitrification reaction of the nitrification liquid that the aeration tank 13 returns to the anaerobic tank 11 or the exchange tank 12.

In this way, after being treated in the exchange tank 12, the raw water is supplied to the anaerobic tank 6 for denitrification treatment, and further, is supplied to the aeration tank 13 for aerobic biological treatment by aeration and agitation. Next, it is supplied to the settling tank 8 from the aeration tank 13, and solid-liquid components are separated in the settling tank 8, and then the separated liquid part is properly discharged. In addition, the separated and precipitated solid part sludge is supplied to the thickener 9 and then supplied to the dissolving tank 2 . In this case, the aeration tank 13 has the functions of BOD removal and nitrification. A part of the nitrification liquid which is the treatment liquid in the aeration tank 13 is returned to the preceding anaerobic tank 11, preferably, to the anaerobic tank 6 (not shown).

Furthermore, the sludge that has been solubilized in the solubilization tank 2 is returned to the exchange tank 12, thereby, in the exchange tank 12, the anaerobic tank 6, the aeration tank 13, the sedimentation tank 8, the thickener 9, and the solubilized sludge Circulation in tank 2. In addition, the sludge separated in the sedimentation tank 8 is supplied to the previous anaerobic tank 11 in addition to the thickener 9 . In addition, the sludge is also returned from the anaerobic tank 4 or the exchange tank 12 to the preceding anaerobic tank 11 .

Preferably, the HRT of the dissolving tank 2 is set to 12 to 72 hours as in Embodiment 3, more preferably to 24 to 72 hours, and most preferably to 36 to 48 hours.

The HRT other than the dissolution tank 2 is preferably 0.5 to 1.5 hours in the anaerobic tank 11, 0.5 to 2 hours in the anaerobic tank 4, 0.5 to 1 hour in the exchange tank 12, and 0.5 to 1 hour in the anaerobic tank 12. 1 to 3 hours in the anaerobic tank 6, 3 to 6 hours in the aeration tank 13, more preferably 0.5 to 1 hour in the anaerobic tank 11, and 0.5 to 1 hour in the anaerobic tank 4 , 0.5 to 1 hour in the exchange tank 12, 1 to 2 hours in the anaerobic tank 6, and 3.5 to 5 hours in the aeration tank 13.

In addition, thermophilic bacteria are used as microorganisms that produce soluble enzymes that solubilize sludge. In particular, bacteria of the genus Bacillus or bacteria of the genus Geobacillus disclosed in Embodiment 1 are preferably used.

In addition, it is desirable to set the temperature during the solubilization treatment to 50 to 90° C. as in Embodiment 1. When using aerobic thermophilic bacteria such as bacteria of the genus Bacillus, it is preferable to set the temperature The range is 55-70°C, more preferably, especially the range 60-65°C. In addition, the pH at the time of the solubilization treatment is set to be in the range of pH 6-9 as in Embodiment 1, preferably in the range of 7-8.

In addition, the processing apparatus in this embodiment is equipped with the concentrator 9, however, the provision of the concentrator 9 is an essential condition of this invention.

(Embodiment 7)

In the present embodiment, as shown in FIG. 8 , a nitrification tank 10 is provided in the subsequent step of the dissolving tank 2 , and this point is the same as that of the sixth embodiment described above.

That is, in this embodiment, the sludge that has undergone solubilization treatment in the solubilization tank 2 is supplied to the nitrification tank 10, and the ammonia in the sludge is converted into nitrous acid or nitric acid in the nitrification tank 10, and then returned to the exchange tank. Slot 12. In addition, the sludge separated from the sedimentation tank 8 is supplied to the thickener 9 and returned to the previous anaerobic tank 11 in the same manner as in the sixth embodiment, and is also directly supplied to the nitrification tank 10 in this embodiment. .

The other configurations and processing procedures are the same as those in Embodiment 6, so descriptions thereof are omitted.

Also, the HRT of the dissolving tank 2 is preferably set at 12 to 72 hours as in Embodiment 5, more preferably at 18 to 48 hours, and most preferably at 20 to 72 hours. 36 hours.

In addition, thermophilic bacteria are used as microorganisms that produce soluble enzymes that solubilize sludge. In particular, bacteria of the genus Bacillus or bacteria of the genus Geobacillus disclosed in Embodiment 1 are preferably used.

Furthermore, it is desirable that the temperature during the solubilization treatment be set at 50 to 90° C. as in Embodiment 1, and in the case of using an aerobic thermophilic bacterium such as Bacillus, it is preferable to set the temperature in the range of 55-70°C, more preferably, especially 60-65°C. In addition, the pH at the time of the solubilization treatment is set to be in the range of pH 6-9 as in Embodiment 1, preferably in the range of 7-8.

(Embodiment 8)

The treatment device in this embodiment, as shown in Figure 9, is equipped with dissolved oxygen reduction tank 16, anaerobic tank 4, anaerobic tank 6, aeration tank 13, sedimentation tank 8, concentration tank 9, and dissolving tank 2 . In this embodiment, in addition to supplying the treated water treated in the anaerobic tank 2 to the anaerobic tank 4, the treated water treated to reduce dissolved oxygen in the dissolved oxygen reduction tank 16 is also supplied to the anaerobic tank 4. Slot 6.

The treated water supplied to the anaerobic tank 6 for denitrification treatment is further supplied to the aeration tank 13 for aerobic treatment by aeration and agitation, and then supplied to the sedimentation tank 8 for solid-liquid separation. At this time, the separated liquid component is properly discharged, and the separated solid component, that is, sludge is supplied to the concentrator 9 , and a part of the sludge is returned to the aeration tank 13 .

In addition, a part of the nitrification liquid which is the treatment liquid in the aeration tank 13 is returned to the anaerobic tank 6 via the dissolved oxygen reduction tank 16 to perform denitrification treatment of the nitrification liquid. Furthermore, the denitrification efficiency can be stabilized by injecting the nitrification liquid into the anaerobic tank to reduce the dissolved oxygen in the nitrification liquid.

Furthermore, the sludge concentrated by the thickener 9 is supplied to the solubilization tank 2, is solubilized, and is returned to the dissolved oxygen reduction tank 16 after that.

In addition, the sludge supplied to the anaerobic tank 6 is also returned to the anaerobic tank 4, and then returned to the dissolved oxygen reduction tank 16 from the anaerobic tank 4.

Preferably, the HRT of the dissolving tank 2 is set to 12 to 72 hours as in Embodiment 3, more preferably to 24 to 72 hours, and most preferably to 36 to 48 hours.

The HRT other than the dissolving tank 2 is set, preferably 0.15 to 0.3 hours in the dissolved oxygen reduction tank 16, 0.5 to 2 hours in the anaerobic tank 4, 1 to 3 hours in the anaerobic tank 6, and aeration 3 to 6 hours in the tank 13, more preferably 0.17 to 0.25 hours in the dissolved oxygen reduction tank 16, 1 to 1.5 hours in the anaerobic tank 4, 1 to 2 hours in the anaerobic tank 6, and aeration 3.5 to 5 hours in tank 13.

In addition, thermophilic bacteria are used as microorganisms that produce soluble enzymes that solubilize sludge. In particular, bacteria of the genus Bacillus or bacteria of the genus Geobacillus disclosed in Embodiment 1 are preferably used.

Furthermore, it is desirable that the temperature during the solubilization treatment be set at 50 to 90° C. as in Embodiment 1, and in the case of using an aerobic thermophilic bacterium such as Bacillus, it is preferable to set the temperature in the range of 55-70°C, more preferably, especially 60-65°C. In addition, the pH at the time of the solubilization treatment is set to be in the range of pH 6-9 as in Embodiment 1, preferably in the range of 7-8.

(Embodiment 9)

In this embodiment, as shown in FIG. 10 , a point that a nitrification tank 10 is provided in a subsequent step of the solubilization tank 2 is different from the eighth embodiment described above.

That is: in this embodiment, the sludge solubilised in the solubilization tank 2 is supplied to the nitrification tank 10, and the ammonia in the sludge is converted into nitrous acid or nitric acid in the nitrification tank 10 and then returned to the dissolved oxygen reduction tank 16. In addition, a part of the sludge in the sedimentation tank 8 is supplied to the nitrification tank 10 to maintain the nitrification treatment.

The other configurations and processing procedures are the same as those in the eighth embodiment, so descriptions thereof are omitted.

Also, the HRT of the dissolving tank 2 is preferably set at 12 to 72 hours as in Embodiment 5, more preferably at 18 to 48 hours, and most preferably at 20 to 72 hours. 36 hours.

In addition, thermophilic bacteria are used as microorganisms that produce soluble enzymes that solubilize sludge. In particular, bacteria of the genus Bacillus or bacteria of the genus Geobacillus disclosed in Embodiment 1 are preferably used.

Furthermore, it is desirable that the temperature during the solubilization treatment be set at 50 to 90° C. as in Embodiment 1, and in the case of using an aerobic thermophilic bacterium such as Bacillus, it is preferable to set the temperature in the range of 55-70°C, more preferably, especially 60-65°C. In addition, the pH at the time of the solubilization treatment is set to be in the range of pH 6-9 as in Embodiment 1, preferably in the range of 7-8.

(Embodiment 10)

The organic wastewater treatment device of this embodiment is equipped with an anaerobic tank 4 , anaerobic tank 6 , aeration tank 13 , sedimentation tank 8 , and dissolving tank 2 as shown in FIG. 11 .

In the present embodiment, raw water is anaerobically treated in the anaerobic tank 4 and phosphorus components in the sludge are discharged, and then supplied to the anaerobic tank 6 and subjected to denitrification treatment in the anaerobic tank 6 . Next, the treatment liquid denitrified in the anaerobic tank 6 is supplied to the aeration tank 13 , and ammonia contained in the sludge is converted into nitrous acid or nitric acid in the aeration tank 13 . That is, nitrification treatment is performed in the aeration tank 13 .

Next, the treatment liquid treated by nitrification in the aeration tank 13 is supplied to the sedimentation tank 8 . And in the said settling tank 8, solid-liquid separation is carried out and the separated liquid part is discharged. In addition, while a part of the sludge of the solid part separated and precipitated is supplied to the solubilization tank 2, the remaining part is used as return sludge. The mud is returned to the anaerobic tank 4.

The sludge after the solubilization treatment is returned to the anaerobic tank 6, thereby repeatedly performing the denitrification treatment in the anaerobic tank 6, the treatment in the aeration tank 13, the solid-liquid separation in the sedimentation tank 8, and the solid-liquid separation in the solubilization tank. 2 in the solubilization treatment. In addition, part of the nitrification liquid treated in the aeration tank 13 is returned to the anaerobic tank 6 or the anaerobic tank 4 , and denitrification treatment is performed in the anaerobic tank 6 .

Preferably, the HRT of the dissolving tank 2 is set to 12 to 72 hours as in Embodiment 3, more preferably to 24 to 72 hours, and most preferably to 36 to 48 hours.

The HRT other than the dissolving tank 2 is set, preferably 0.15 to 0.3 hours in the dissolved oxygen reduction tank 16, 0.5 to 2 hours in the anaerobic tank 4, 1 to 3 hours in the anaerobic tank 6, and aerobic 3 to 6 hours in the tank 17, more preferably 0.17 to 0.25 hours in the dissolved oxygen reduction tank 16, 1 to 1.5 hours in the anaerobic tank 4, 1 to 2 hours in the anaerobic tank 6, and aerobic 3.5 to 5 hours in tank 17.

In addition, thermophilic bacteria are used as microorganisms that produce soluble enzymes that solubilize sludge. In particular, bacteria of the genus Bacillus or bacteria of the genus Geobacillus disclosed in Embodiment 1 are preferably used.

Furthermore, it is desirable that the temperature during the solubilization treatment be set at 50 to 90° C. as in Embodiment 1, and in the case of using an aerobic thermophilic bacterium such as Bacillus, it is preferable to set the temperature in the range of 55-70°C, more preferably, especially 60-65°C. In addition, the pH at the time of the solubilization treatment is set to be in the range of pH 6-9 as in Embodiment 1, preferably in the range of 7-8.

(Embodiment 11)

In this embodiment, as shown in FIG. 12 , the sludge that has been solubilized in the solubilization tank 2 is returned to the anaerobic tank 4, which is different from the case of Embodiment 10 in which it is returned to the anaerobic tank 6. .

Anaerobic treatment is performed in the anaerobic tank 4, denitrification treatment is performed in the anaerobic tank 6, nitrification treatment is performed in the aeration tank 13, solid-liquid components are separated in the sedimentation tank 8, and solubilization is performed in the solubilization tank 2 The processing steps are the same as those in Embodiment 10, and therefore description thereof will be omitted. In this embodiment, a part of the nitrifying liquid is also returned to the anaerobic tank 6 or the anaerobic tank 4 .

Preferably, the HRT of the dissolving tank 2 is set to 12 to 72 hours as in Embodiment 3, more preferably to 24 to 72 hours, and most preferably to 36 to 48 hours.

In addition, thermophilic bacteria are used as microorganisms that produce soluble enzymes that solubilize sludge. In particular, bacteria of the genus Bacillus or bacteria of the genus Geobacillus disclosed in Embodiment 1 are preferably used.

In addition, it is desirable to set the temperature during the solubilization treatment to 50 to 90°C, which is the same as in Embodiment 1. When using aerobic thermophilic bacteria such as Bacillus, it is preferable to set the temperature in the range of 55-70°C, more preferably, especially 60-65°C. In addition, the pH at the time of the solubilization treatment is set to be in the range of pH 6-9 as in Embodiment 1, preferably in the range of 7-8.

(implementation mode 1 2)

In this embodiment, as shown in FIG. 13 , a nitrification tank 10 is provided at a step after the dissolving tank 2 . In the present embodiment, the sludge treated in the dissolving tank 2 is supplied to the nitrification tank 10 , and ammonia in the sludge is converted into nitrous acid or nitric acid in the nitrification tank 10 and returned to the anaerobic tank 6 . In addition, sludge is supplied from the sedimentation tank 8 to the nitrification tank 10 .

Anaerobic treatment is performed in the anaerobic tank 4, denitrification treatment is performed in the anaerobic tank 6, nitrification treatment is performed in the aeration tank 13, solid-liquid components are separated in the sedimentation tank 8, and solubilization is performed in the solubilization tank 2 The processing steps are the same as those in Embodiment 11, and therefore description thereof will be omitted.

Also, the HRT of the dissolving tank 2 is preferably set at 12 to 72 hours as in Embodiment 5, more preferably at 18 to 48 hours, and most preferably at 20 to 72 hours. 36 hours.

In addition, thermophilic bacteria are used as microorganisms that produce soluble enzymes that solubilize sludge. In particular, bacteria of the genus Bacillus or bacteria of the genus Geobacillus disclosed in Embodiment 1 are preferably used.

In addition, it is desirable to set the temperature during the solubilization treatment to 50 to 90°C, which is the same as in Embodiment 1. When using aerobic thermophilic bacteria such as Bacillus, it is preferable to set the temperature in the range of 55-70°C, more preferably, especially 60-65°C. In addition, the pH at the time of the solubilization treatment is set to be in the range of pH 6-9 as in Embodiment 1, preferably in the range of 7-8.

(Embodiment 13)

In this embodiment, a nitrification tank 10 is provided in the same manner as Embodiment 12 in the subsequent steps of the dissolving tank 2, and the treated sludge in the nitrification tank 10 is returned to the anaerobic tank 4 as shown in Figure 14 This point is different from Embodiment 12 in which it is returned to the anaerobic tank 6 .

Anaerobic treatment is performed in the anaerobic tank 2, denitrification treatment is performed in the anaerobic tank 6, nitrification treatment is performed in the aeration tank 13, solid-liquid components are separated in the sedimentation tank 8, and solubilization is performed in the solubilization tank 2 The processing steps are the same as those in Embodiment 10, and therefore description thereof will be omitted.

Also, the HRT of the dissolving tank 2 is preferably set at 12 to 72 hours as in Embodiment 5, more preferably at 18 to 48 hours, and most preferably at 20 to 72 hours. 36 hours.

This embodiment is also the same as the twelfth embodiment, and it is necessary to supply the sludge from the sedimentation tank 8 to the nitrification tank 10 .

In addition, thermophilic bacteria are used as microorganisms that produce soluble enzymes that solubilize sludge. In particular, bacteria of the genus Bacillus or bacteria of the genus Geobacillus disclosed in Embodiment 1 are preferably used.

In addition, it is desirable to set the temperature during the solubilization treatment to 50 to 90°C, which is the same as in Embodiment 1. When using aerobic thermophilic bacteria such as Bacillus, it is preferable to set the temperature in the range of 55-70°C, more preferably, especially 60-65°C. In addition, the pH at the time of the solubilization treatment is set to be in the range of pH 6-9 as in Embodiment 1, preferably in the range of 7-8.

(Embodiment 14)

The organic wastewater treatment device in this embodiment is composed of a reaction tank 1 , a dissolving tank 2 , and a storage tank 3 as shown in FIG. 15 . In the reaction tank 1, the same organic wastewater treatment as in the first embodiment is performed.

In this embodiment, as shown in FIG. 16 , the steps of anaerobic treatment by stirring and aerobic treatment by aeration are repeated three times each, and thereafter, the aeration by stopping aeration is performed in a cycle. Process of precipitation, solid-liquid separation, and solubilization treatment. In the reaction tank 1 , the process of repeating anaerobic treatment and aerobic treatment, precipitation, and solid-liquid separation are performed, and the solubilization treatment is performed in the solubilization tank 2 .

It is possible to adjust the time of each process to perform a series of intermittent treatment of wastewater treatment from the inflow of raw water to the discharge of treated water several times a day (for example, 2 to 4 times). However, depending on the properties and amount of wastewater, etc. Adjust the treatment time of each process to perform about once a day, or batch treatment twice a day.

The process time of wastewater treatment is, for example, 60 minutes for inflow, 60 minutes for anaerobic treatment, 70 minutes for aerobic treatment, 30 minutes for anaerobic treatment, 80 minutes for aerobic treatment, 20 minutes for anaerobic treatment, and Oxygen treatment for 10 minutes, precipitation for 40 minutes, and discharge for 40 minutes.

In this embodiment, nitrification is performed in the aerobic treatment process, and denitrification treatment is performed in the anaerobic treatment process.

The solubilized solubilized solution is returned to the reaction tank 2 in the first (first) aerobic treatment step. The timing of its return depends on the treatment time of the first aerobic treatment process, but it is set to 30 minutes to 3 hours before stopping the aeration, preferably, 30 minutes to 1 hour before.

In this embodiment, the storage tank 3 is provided in the step behind the dissolving tank 2, so the solubilizing liquid treated in the dissolving tank 2 can be temporarily stored with the storage tank 3, thereby, in the first aerobic It is easy to adjust the timing and amount of returning the solubilized liquid to the reaction tank 2 in the treatment process.

The HRT of the dissolving tank 2 is preferably set at 12 to 72 hours as in Embodiment 1, more preferably at 18 to 48 hours, and most preferably at 20 to 36 hours.

As microorganisms that produce a soluble enzyme that dissolves sludge, thermophilic bacteria are used, preferably, the bacteria of the genus Bacillus or the genus Geobacillus disclosed in Embodiment 1 are used.

In addition, it is desirable to set the temperature during the solubilization treatment to 50 to 90°C, which is the same as in Embodiment 1. When using aerobic thermophilic bacteria such as Bacillus, it is preferable to set the temperature in the range of 55-70°C, more preferably, especially 60-65°C. In addition, the pH at the time of the solubilization treatment is set to be in the range of pH 6-9 as in Embodiment 1, preferably in the range of 7-8.

(Embodiment 15)

The organic waste water treatment device in this embodiment, as shown in FIG. 17 , is provided with a storage tank 3 at a step behind the reaction tank 1 , and is further provided with a dissolving tank 2 at a step behind it. In the present embodiment, the nitrified and denitrified sludge is stored in the storage tank 3, and the sludge is supplied to the solubilization tank 2 according to the amount of solubilization treatment required.

By supplying only the amount of sludge requiring solubilization treatment to the solubilization tank 2 in this way, the amount of the solubilization liquid returned to the aerobic treatment step can be adjusted in advance.

Repeating the steps of anaerobic treatment and aerobic treatment, followed by precipitation and separation of solid and liquid components is the same as in Embodiment 14.

The HRT of the dissolving tank 2 is preferably set at 12 to 72 hours as in Embodiment 5, more preferably at 18 to 48 hours, and most preferably at 20 to 36 hours.

In addition, thermophilic bacteria are used as microorganisms that produce soluble enzymes that solubilize sludge. In particular, bacteria of the genus Bacillus or bacteria of the genus Geobacillus disclosed in Embodiment 1 are preferably used.

In addition, it is desirable to set the temperature during the solubilization treatment to 50 to 90°C, which is the same as in Embodiment 1. When using aerobic thermophilic bacteria such as Bacillus, it is preferable to set the temperature in the range of 55-70°C, more preferably, especially 60-65°C. In addition, the pH at the time of the solubilization treatment is set to be in the range of pH 6-9 as in Embodiment 1, preferably in the range of 7-8.

(Embodiment 16)

This embodiment is an embodiment in which, when phosphorus is contained in the sludge generated by biological treatment such as nitrification and denitrification, a device for removing phosphorus therein is provided.

In this embodiment, phosphorus is removed by adding a flocculant such as polyaluminum chloride to the rear stage side of the sedimentation tank 8 as in the above-mentioned embodiments, or by installing a filter material to remove phosphorus by flocculation filtration.

In each of the above-mentioned embodiments, in the embodiment having an anaerobic treatment and an aerobic treatment step (aeration treatment step), when the treated water or sludge contains phosphorus, the phosphorus is released from the sludge in the anaerobic treatment step. Microbial emissions in the aerobic treatment process are bound by microorganisms. However, even if phosphorus is discharged or combined in this way, there is still a concern that the treatment solution containing phosphorus will be discharged out of the system when the solubilization treatment of sludge is used, and it cannot be achieved by both anaerobic treatment and aerobic treatment. The purpose of the function of discharging phosphorus or binding phosphorus.

Therefore, phosphorus contained in treated water or sludge can be positively removed by providing the above-mentioned phosphorus removal device. This applies to both continuous and batch processing.

(Embodiment 17)

In this embodiment, as the dephosphorization device, it is changed to a device using the above-mentioned flocculant or the like, and its configuration is as follows. A phosphorus release tank equipped with a phosphorus separation device is provided on the rear side of the sedimentation tank 8, and the phosphorus separated from the sedimentation tank 8 Sludge, in the sludge state such as anaerobic state, heating state, etc. in the phosphorus release tank, further release phosphorus, the released phosphorus is separated into the eluate of phosphorus sludge and phosphorus, and phosphorus Phosphorus is removed by adding flocculant etc. to the release liquid. Then, solubilize the phosphorus release sludge.

Therefore, in the present embodiment, various tanks as in the above-mentioned embodiments may be provided on the front side of the settling tank 8 . These are applicable to both continuous processing and batch processing.

(Embodiment 18)

In this embodiment, iron plates, iron particles, steel wool, etc. are put into the reaction tank 1, aeration tank 13, nitrification tank 10, solubilization tank 2, anaerobic tank 6, etc. of the above-mentioned embodiments to make the phosphorus component adhere Implementation of phosphorus removal on iron.

In this embodiment, there is no need to use the flocculant as in the above-mentioned embodiment, and it is not necessary to set up a phosphorus discharge tank for discharging phosphorus like the above-mentioned embodiment 17. , soluble tank 2, anaerobic tank 6, etc. are put into iron raw materials, and phosphorus is attached to the iron raw materials, so that phosphorus can be easily removed.

(Other implementations)

Also, in the above-mentioned Embodiments 3, 4, 5, etc., as the liquid to be treated, an acid fermentation liquid obtained by decomposing and fermenting leftover gas discharged from a food factory is used, but the type of liquid to be treated is not limited thereto. Other types are fine too.

In addition, as in the above-mentioned embodiments 3, 4, and 5, it is not an essential condition for the present invention to arrange a fermentation liquid storage tank 3, but as shown in FIG. 4. Treatment devices for primary aeration tank 5, anaerobic tank 6, secondary aeration tank 7, sedimentation tank 8, and dissolving tank 2. For example, in the case of treating only sewage from a sewage treatment plant, a treatment device as shown in FIG. 18 can be suitably used.

Moreover, the exhaust gas is discharged from the dissolution tank 2, but by introducing such exhaust gas into the nitrification tank or aeration tank in the above-mentioned embodiment, it is possible to introduce high-temperature exhaust gas into the nitrification tank while removing the odor of the exhaust gas. Or the aeration tank, increasing the temperature of each tank is higher than the temperature when aeration is carried out based on the usual air, thus the activity of microorganisms can be improved, thereby improving the treatment efficiency, therefore, the above scheme is preferred.

Moreover, it can be used regardless of the kind of organic wastewater to be treated.

Claims (19)

1. A treatment method for organic waste water is a method in which organic waste water is treated with a biological method, and is characterized in that it has: For the sludge produced by nitrification and denitrification treatment after nitrification and denitrification treatment of organic wastewater, thermophilic bacteria are used for solubilization treatment at a temperature of 50-90°C. 2. the processing method of organic waste water according to claim 1, is characterized in that, The nitrification and denitrification treatment of organic wastewater is carried out intermittently in the reaction tank (1), the nitrification treatment is carried out by aeration, and the denitrification treatment is carried out by stopping the aeration treatment, and before the aeration treatment is stopped 30 minutes to 3 hours Return the solubilized treatment liquid to the reaction tank (1). 3. the processing method of organic waste water according to claim 2, is characterized in that, Before the aeration treatment is stopped for 30 minutes to 1 hour, the solubilization treatment liquid is returned to the reaction tank (1). 4. the processing method of organic waste water according to claim 1, is characterized in that, The nitrification and denitrification treatment of organic wastewater is carried out through anaerobic treatment process, primary aeration process, denitrification process in anaerobic tank, and secondary aeration process. 5. the processing method of organic waste water according to claim 1, is characterized in that, The nitrification and denitrification treatment of organic wastewater is carried out through the denitrification process in the anaerobic tank, the anaerobic treatment process, the treatment process in the exchange tank, the denitrification process in the anaerobic tank, and the aeration process. 6. The method for treating organic wastewater according to claim 4 or 5, characterized in that nitrification is carried out after solubilization treatment. 7. the processing method of organic waste water according to claim 1, is characterized in that, The nitrification and denitrification treatment of organic wastewater is carried out through anaerobic treatment process, denitrification process in anaerobic tank, and aeration process, and at the same time, the dissolved oxygen in the treatment liquid after solubilization treatment is reduced. 8. the processing method of organic wastewater according to claim 1, is characterized in that, The nitrification and denitrification treatment of organic wastewater is carried out through anaerobic treatment process, denitrification process in anaerobic tank, and aeration process. 9. The method for treating organic waste water according to claim 1, characterized in that the sludge is concentrated before solubilization treatment. 10. The method for treating organic wastewater according to claim 1, wherein the thermophilic bacteria that dissolve the sludge are aerobic thermophilic bacteria. 11 . The method for treating organic wastewater according to claim 10 , wherein the aerobic thermophilic bacteria are microorganisms of the genus Bacillus, ie microorganisms of the genus Bacillus. 12. The method for treating organic wastewater according to claim 1, further comprising a step of removing phosphorus in sludge generated by nitrification and denitrification treatment. 13. An organic wastewater treatment device is a device for carrying out biological treatment of organic wastewater, characterized in that, It has: a device for nitrification and denitrification of organic waste water; and a dissolving tank for dissolving sludge produced by nitrification and denitrification at a temperature of 50-90°C by thermophilic bacteria. 14. The treatment device of organic wastewater according to claim 13, characterized in that, The device for nitrification and denitrification of organic wastewater is a device for nitrification and denitrification in a batch reaction tank (1), the nitrification treatment is carried out by aeration, the denitrification treatment is carried out by stopping the aeration, and the The solubilized treatment liquid is returned to the reaction tank (1) 30 minutes to 3 hours before the aeration treatment. 15. The treatment device of organic wastewater according to claim 13, characterized in that, The device for nitrification and denitrification of organic waste water is a device for nitrification and denitrification through anaerobic tank (4), primary aeration tank (5), anaerobic tank (6) and secondary aeration tank (7). 16. The treatment device of organic wastewater according to claim 13, characterized in that, The device for nitrification and denitrification of organic wastewater is carried out through anaerobic tank (11), anaerobic tank (4), exchange tank (12), anaerobic tank (6) and aeration tank (13) for nitrification , Denitrification device. 17. The treatment device of organic wastewater according to claim 13, characterized in that, The device for nitrification and denitrification of organic wastewater is a device for nitrification and denitrification through anaerobic tank (4), anaerobic tank (6), and aeration tank (13), and is equipped with a device to reduce The dissolved oxygen reduction tank (16) of the dissolved oxygen. 18. The treatment device of organic wastewater according to claim 13, characterized in that, The device for nitrification and denitrification of organic waste water is a device for nitrification and denitrification through anaerobic tank (4), anaerobic tank (6) and aeration tank (13). 19. The treatment device for organic wastewater according to claims 13 to 18, characterized in that, It has a device for removing phosphorus contained in sludge generated by nitrification and denitrification treatment.

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