JP2008055423A - Method for boiling sewage - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sewage treatment method in which organic sludge is dissolved thermally before carrying out a step of treating sewage with a microbe to facilitate the decomposition of the dissolved organic sludge by the microbe and particularly organic sludge can be dissolved efficiently by easy temperature management. <P>SOLUTION: In a method for treating sewage microbiologically, when the fluidity of raw sewage is low, water is added to the raw sewage in an agitation tank to dilute the raw sewage so that the water-added sewage has about 10,000 ppm or lower BOD concentration and increase the fluidity thereof before the raw sewage is introduced into a boiling tank. The water-diluted sewage agitated in the agitation tank is introduced into the boiling tank to heat the introduced sewage and adjust the temperature of the heated sewage to 55-98°C. After the organic sludge in the boiling tank is solubilized, the boiled sewage is sent to a step of decomposing the boiled sewage by the microbe. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for efficiently purifying organic wastewater such as domestic wastewater and livestock wastewater discharged in large quantities.

  In order to purify organic wastewater such as domestic wastewater, livestock wastewater, and business wastewater from hotels and restaurants, various sewage purification methods using microorganisms have been proposed and implemented.

In general, there are many activated sludge processes in which sewage in a sewage treatment tank is aerated and organic sludge is decomposed by aerobic microorganisms.
Usually, in the case of this method, an optimum temperature for the aerobic microorganism, that is, a temperature condition slightly higher than normal temperature is preferred.

In general, even when aerobic microorganism treatment is performed by aeration, when the temperature of sewage is low, the dissolved oxygen dissolved in water increases and the supply of oxygen increases, but the activity of microorganisms is impaired. It becomes active and the processing capacity cannot be increased.
Conversely, when the temperature is high, the activity of microorganisms increases when the temperature is low, but the dissolved oxygen dissolved in water decreases and the supply of oxygen decreases. The processing capacity could not be increased.
That is, there is a problem that the processing capacity is lowered at both low temperature and high temperature. In addition, there is a problem that when the temperature is high, a strong odor is emitted.

Therefore, as a method of reducing the burden of the processing amount in such a processing tank, before flowing into the processing tank, solid oil such as garbage is separated and removed from the garbage receptacle or a grease trap is installed. Pre-separation removal of the minute is performed.
Further, there is a mitigation method by using a flocculant or the like, but a commonly used flocculant such as a cation is not preferable for the environment, and therefore there is a problem that secondary treatment of the flocculant has to be performed.

  Furthermore, in a sewage treatment method having a low treatment capacity, it is generally adopted that a large amount of sewage can be treated by increasing the scale of the treatment tank. However, it is very difficult to secure a large facility site nearby that can be treated sufficiently in urban areas.

Therefore, even if it is simply aerated, there is a limit, so in order to further increase the processing capacity, the sewage water becomes a habitat of microorganisms and promotes the propagation of microorganisms and increases the sludge decomposition capacity so that many microorganisms are stagnant. A sewage treatment tank into which a microbial carrier made of a material having a large contact surface area is introduced.
In a sewage treatment tank using such a carrier, when sewage containing a large amount of fats and oils or sewage with a high concentration of SS flows, an oil film that cannot be decomposed by ordinary microorganisms or a sewage substance that cannot be decomposed sticks to the surface of the microbial carrier. In such a case, there is a problem in that any carrier is clogged in the voids and meshes, the original function as the carrier is lowered, and in the worst case, the processing function cannot be obtained.

Also, in the treatment method with anaerobic microorganisms, the sewage treatment tank is sealed, and organic sludge in the anaerobic treatment tank is decomposed into methane, hydrogen sulfide gas, etc. by various decomposing synthetic bacteria. In some cases, the temperature becomes high with heat generation, and there is a case where the temperature is forced to be set to a high temperature environment suitable for anaerobic bacteria to promote decomposition.
However, in this method, solubilization of organic sludge cannot be obtained efficiently, and in this temperature adjustment, the temperature is adjusted to about 50 ° C. to 70 ° C. preferred by normal anaerobic microorganisms. At higher temperatures, various degrading bacteria weaken and eventually die, so there was a limit to the degree of high temperature.

Therefore, technical proposals have been made to treat the above-mentioned problems in microbial treatment more efficiently from another viewpoint.
It is called a hydrothermal / biological method, and it is intended to dissolve sludge at a high temperature of 150 ° C. to 300 ° C. by a hydrothermal reactor and facilitate subsequent decomposition by microorganisms.
In the case of this method, since the hydrothermal reaction is performed, the treatment time efficiency can be improved by boiling the sewage for a short time and dissolving the organic matter. Since this occurs, a large amount of energy due to heat of vaporization is consumed.
Further, when pressurization is performed in order to suppress the heat of vaporization, the high-temperature pressurization apparatus becomes complicated and the apparatus therefor has to be large.

  The present invention has been made in view of the above circumstances, and before entering the sewage treatment process by microorganisms, organic sewage is dissolved by a hydrothermal reaction so that subsequent decomposition by microorganisms can be facilitated, and domestic wastewater Even if sewage generation exceeds the capacity of various sewage purification systems equipped with sewage treatment tanks with microorganisms for treating organic sewage such as livestock effluent, business effluents such as hotels and restaurants, before that It is possible to respond sufficiently by processing, especially in terms of equipment, it is possible to make it extremely compact, temperature management can be easily done without boiling or pressurizing, and organic sludge can be efficiently mixed by mixing A sewage treatment method that can be dissolved is provided.

  In order to solve the above problems, the sewage simmering treatment method in the sewage microbiological treatment method of the present invention mainly involves transferring the sewage treated in the simmering tank directly to the decomposition treatment step with the following microorganisms; There are two types of methods of mixing in a mixing pipe and then transferring to a microbial degradation process.

In the former type, when the raw sewage is low in fluidity, the water is added to the raw sewage in a stirring tank before being introduced into the simmering tank to dilute the BOD concentration to about 10,000 ppm or less to increase the fluidity. The sewage is stirred in the stirring tank.
The stirred sewage is introduced into a simmering tank, and the sewage is heated to adjust the temperature to 55 ° C to 98 ° C.
Then, after the sludge is in a solubilized state in the simmering tank, the sewed sewage is transferred to a decomposition treatment step with microorganisms.

In the latter type of form, when the raw sewage has low fluidity, the water is added to the sewage in the stirring tank before being introduced into the stew tank to dilute the BOD concentration to about 10,000 ppm or less to increase the fluidity. The waste water is stirred in the stirring tank.
The stirred sewage is introduced into a simmering tank, and the sewage is heated to adjust the temperature to 55 ° C to 98 ° C.
Then, after the sludge is solubilized in the simmering tank, the sewage sewage is passed through the mixing pipe together with the injected air, and then mixed in the mixing pipe and then transferred to the decomposition treatment step by microorganisms. It is characterized by.

  Further, in the above configuration, the stirring method of the sewage in the stirring tank is extracted from the stirring tank and pumped and passed through the mixing pipe, and then mixed in the mixing pipe. Agitating and circulating back inside.

  Further, in the above configuration, the method of stirring the sewage in the stirring tank is to mix the sewage in the mixing pipe by drawing out and feeding the sewage in the stirring tank and passing it through the mixing pipe together with the injected air. The mixture is stirred and returned to the stirring tank.

  Moreover, the said structure WHEREIN: The stirring method of the sewage in the said stirring tank is characterized by stirring the sewage in the stirring tank at high speed.

  Further, in the above configuration, the sewage agitation method in the agitation tank is the same as the sewage agitation method in the agitation tank by pulling out the sewage water in the agitation tank and feeding it through a mixing pipe. It is characterized by combining stirring circulation returning to the stirring tank after mixing in the mixing pipe and stirring at high speed for the sewage in the stirring tank.

  Moreover, in the said structure, when stirring in the said stirring tank, the temperature of the sewage in a stirring tank is adjusted to 55 degreeC-98 degreeC, It is characterized by the above-mentioned.

  In the above configuration, the method for stirring sewage in the stirring tank is to stir the sewage in the stirring tank at a low speed for several minutes while adjusting the temperature to 55 ° C to 98 ° C, and then the stirring tank. The sewage is extracted and pumped, and passed through the mixing pipe, whereby mixing in the mixing pipe is performed, and then stirring and returning to the stirring tank is performed.

  Moreover, in the configuration of each of the above embodiments, before the sewage is passed through the first mixing pipe, the microbial hard-to-decompose solids contained in the sewage are removed.

  Furthermore, in the configuration of each of the above embodiments, sodium hydroxide, a surfactant, or an enzyme agent is added to sewage during or before stirring.

The present invention is as described above, and before entering the sewage treatment process with microorganisms, the sewage is stirred and pulverized in a stirring tank, and then the fine organic sludge is heated at a high temperature of 55 ° C to 98 ° C. At the same time as boiled, it is passed through the mixing pipe 1 for mixing, thereby dissolving and destroying the cell walls of the organisms contained in the sewage, synergistically increasing the dissolution efficiency of organic matter, solubilization rate of 90% or more It is 5 to 10 times faster than before and can be processed for a very short time.
In addition, dissolution efficiency can be further increased by adding sodium hydroxide, a surfactant, or an enzyme agent to sewage during or before mixing.

In addition, mixing with the mixing pipe significantly increases the dissolved oxygen concentration in the sewage D, and promotes the consumption of oxygen from the aerobic microorganisms in the sewage treatment tank later by the microorganisms, so that the organic matter It comes to disassemble.
For this reason, the load on the sewage treatment capacity of the sewage treatment tank is greatly reduced.
As a result, even if sewage generation exceeding the treatment capacity occurs for various sewage purification systems equipped with sewage treatment tanks with microorganisms for treating organic sewage such as business wastewater in hotels and restaurants, the present invention. By pre-processing, it became possible to cope with the equipment as it was.

  In addition, this method makes it possible to make the device extremely compact, and since temperature control can be easily performed without boiling or pressurization, it is possible to realize a significant reduction in equipment costs and management costs.

The sewage simmering treatment method in the sewage microbiological treatment method of the present invention is a method of directly transferring the sewage treated in the simmering tank to the decomposition process step with the following microorganisms (shown in the flow diagram of FIG. 1), There are two types of methods of mixing in a mixing pipe and then transferring to a microbial degradation process.
These embodiments will be described below based on examples of the drawings.

  First, a method for stirring and circulating the sewage in the simmering tank shown in the flowchart of FIG. 1 will be described in detail with reference to FIGS. 2 to 6 showing an apparatus for carrying out the method.

  In this form, the raw sewage G has a high fluidity and a low fluidity. When the fluidity is high (when the BOD concentration is about 10,000 ppm or less), it is not necessary to dilute.

The reason is that when the BOD concentration of sewage is about 13000 ppm, it is difficult to pass through the mixing pipe 1 and the passing efficiency is lowered.
Furthermore, if it is 15000 ppm or more, depending on the size of the pipe diameter, the stirrer 22 may become difficult to operate or may not flow into the mixing pipe 1.

Therefore, when the fluidity is low, as shown in FIG. 7, which is a structure different from the present invention, the raw sewage G is introduced into the microbially difficult-to-decompose solid matter removing device 7 through the water supply pipe 9, A vinyl string, a synthetic resin wrap piece, a plastic piece, a metal piece, a ceramic piece, etc. are poured and removed together with water, and then the ceramic or stainless steel stirring tanks 13 and 21 are removed from the solid matter removing device 7. It may be introduced through the water pipe 8 (there is a different part in FIG. 7 in that the simmering tank 2 is added).
As the solid matter removing device 7, devices such as a wire mesh, a coarsely woven nonwoven screen, and a drum screen can be used.
And in the said stirring tanks 13 and 21, water W is added to the waste water G, BOD density | concentration is diluted to about 10,000 ppm or less, and fluidity | liquidity is improved.

  That is, in this method, raw sewage G is first introduced into the agitation tank 13, and when the raw sewage G has low fluidity, water W is added to the agitation tank 13 to dilute the BOD concentration to about 10000 ppm or less. Then, the fluidity is increased, and the highly fluid wastewater is agitated, and then sent to the simmering tank 2.

And the waste water D is heated within the boiling tank 2, and temperature control is carried out to 55 degreeC-98 degreeC.
At the same time, in the simmering tank 2, the temperature-controlled high temperature sewage D is mixed with the high temperature sewage D in the simmering tank 2 through the water supply pipe 5, and a mixing pipe in which irregularities and alternating tongues are provided in the pipe. It is also possible to continue the agitation circulation that is led to 1 and mixed and returned to the boiled tank 2 by the return pipe 6.
If the hair and the vinyl string are previously removed from the mixing pipe 1 by the microorganism-resolvable solid matter removing device 7 in advance, troubles such as hair clogging can be prevented.

  Then, after about 30 minutes to 1 hour, when the sludge is in a solubilized state in the simmering tank 2, the sewage sewage D is transferred to a decomposition process by the next microorganism.

The boiling tank 2 is provided with an electric heater 3 for temperature adjustment, and the electric heater 3 is connected to a power source via a control unit provided with a temperature sensor installed in the boiling tank.
Then, the sewage D that has been boiled is then sent to the sewage treatment tank 10 by microorganisms through a water pipe 11 by a pump 12.

  The sewage treatment tank 10 is a sewage treatment tank 10 in which a conventional treatment method using microorganisms is carried out, including an aerobic treatment tank, an anaerobic treatment tank, and a complex sewage treatment system S including both. It can be used for most sewage treatment tanks 10.

  As for the method of stirring sewage in the stirring tank 13, mixing by the mixing pipe 1 and stirring by the stirrer 24 can be performed simultaneously as shown in FIG.

The method of the present invention has various forms. As shown in FIG. 2, the sewage D in the agitation tank 13 is guided to the mixing pipe 1 by the pump 15 through the water supply pipe 14, and is stirred again from the water discharge pipe 16. Mixing circulation returning into the tank 13 may be continued for at least several minutes.
At this time, if the heater 19 provided in the stirring tank 13 is heated to 55 ° C. to 98 ° C. and stirred, the organic matter dissolved by hydrothermal heat can be mechanically destroyed by mixing, so a dramatic synergistic effect for solubilization. Appears.

Then, the sewage D that has been subjected to the mixing treatment is fed from the stirring tank 13 through the water feeding pipe 17 by the pump 18 and guided into the simmering tank 2.
Then, the sewage D is heated in the simmering tank 2 by the heater 3 and the temperature is adjusted to 55 ° C. to 98 ° C. When the sludge is solubilized in the simmering tank 2, the sewed sewage D is converted into the above method. Similarly, water is fed to a sewage treatment tank 10 for carrying out a conventional treatment method using microorganisms through a water pipe 11 with a pump 12.

In another embodiment, as shown in FIG. 3, the sewage D in the agitation tank 13 is continuously agitated with a stirrer 24 using a blade by an agitation motor 25, and the agitated sewage in the agitation tank 13 is fed. It is guided by a pump 18 through a water pipe 17 and sent into the simmering tank 2.
In the agitator 24, mixing is continued for a while.
Also at this time, if the heater 19 provided in the stirring tank 13 is stirred in a state heated to 55 ° C. to 98 ° C., the organic matter dissolved by the hydrothermal heat can be mechanically destroyed by mixing, so that it is dramatic for solubilization. A synergistic effect appears.

In addition, as shown in FIG. 4, the method for stirring sewage in the stirring tank 13 may be such that mixing by the mixing pipe 1 and stirring by the stirrer 24 can be performed simultaneously.
Also at this time, if the heater 19 provided in the stirring tank 13 is stirred in a state heated to 55 ° C. to 98 ° C., the organic matter dissolved by the hydrothermal heat can be mechanically destroyed by mixing, so that it is dramatic for solubilization. A synergistic effect appears.

Then, the sewage D that has been boiled is then sent directly to the sewage treatment tank 10 with microorganisms via the water pipe 11 as shown in FIG. Next, the high temperature sewage D in the simmering tank 2 is guided along with the air injected from the air injection pipe 20 to the mixing pipe 1 provided with irregularities and alternating tongues in the pipe by the pump 12 through the water supply pipe 11. There is a method that can be mixed and sent.
In the latter method, fine bubbles can be put in the sewage of the next sewage treatment tank 10 as in the above method. And oxygen in a bubble can be supplied to the aerobic microorganisms in the sewage treatment tank 10, and a sludge decomposition process can be accelerated | stimulated.

  Further, as shown in FIG. 6, the mixing circulation in which the sewage D in the agitation tank 13 is guided to the mixing pipe 1 by the pump 15 through the water supply pipe 14 and returned from the water discharge pipe 16 to the agitation tank 13 is continued for a while. In doing so, if air is injected from the air injection tube 20, the effect of dissolving the sludge is enhanced by the fine bubbles generated thereby.

In addition, as a method for improving dissolution efficiency, in each of the above-described configurations, it is effective to add sodium hydroxide, a surfactant, or an enzyme agent to the sewage during or before mixing.
For example, it has been confirmed by experiments that the efficiency increases by about 10% when 40 kg of sodium hydroxide is added to 10 t of treated sewage.

  In addition, when the mixing pipe 1 is used during the stirring process of stirring sewage or when supplying water to the sewage treatment tank 10, troubles such as clogging in the mixing pipe 1 occur in any case. In order to prevent this, if the hair and the vinyl string are removed in advance by the microorganism-resolvable solid matter removing device 7, the hair removal work is eliminated and smooth management can be performed.

(Function)
As described above, the present invention allows organic sludge to be boiled at a high temperature at which water of 55 ° C. to 98 ° C. does not evaporate and passed through the mixing pipe 1 at the same time without being subjected to pressure boiling at an extremely high temperature of 100 ° C. or higher. By mixing and mixing, the cell walls derived from organisms contained in the sewage are dissolved by heat, and the weakened cell walls are mechanically destroyed by mixing, thereby effectively dissolving the cell fluid into the water. I was able to do it.
That is, it is possible to synergistically increase the dissolution efficiency of organic substances by hydrothermal dissolution and mixing destruction.
In addition, the dissolution efficiency can be further increased by introducing an agent having a property of dissolving an organic substance, that is, sodium hydroxide, a surfactant or an enzyme agent, into sewage during or before stirring.

Further, when mixing is performed by passing air through the mixing pipe 1 and injecting air, the dissolved oxygen concentration in the sewage D is greatly increased. This is very preferable for the aerobic microorganisms in the sewage treatment tank 10 by microorganisms later, and the organic matter is decomposed very actively by consuming the oxygen.
For this reason, the load on the sewage treatment capacity of the sewage treatment tank 10 is greatly reduced.
Further, the bad odor can be prevented by the bubbles generated by the mixing, and there is an advantage that the state of agitation can be confirmed by checking the state of the bubbles contained by sampling the sewage.

(Test Example 1)
Conventionally, the solubilization rate was about 90% after processing for about 6 hours or more, but now it can be made about 90% or more by the treatment for about 30 minutes to 1 hour.
The following is the time required for the temperature when the solubilization rate is 90%.
20 ° C: PH11 (adjustment with caustic soda) 6-12 hours (beaker test)
50 ° C: PH2.5 (adjustment with sulfuric acid) About 2 hours 85 ° C: PH7 About 10 minutes (with stirring)
85 ° C: PH11 (adjustment with caustic soda) 10 minutes (with stirring)

The term “solubilization” as used in the present invention refers to breaking the cell wall of an organism so that the cell fluid inside dissolves in water. The “solubilization rate” is a numerical value obtained by dividing the stock solution COD concentration by the COD concentration “solved-COD concentration (S-COD)” of the cell fluid that has passed through the filter.
To achieve a solubilization rate of 90%, it takes about 6-12 hours at 20 ° C, but at 85 ° C it can be confirmed that the solubilization rate exceeds 90% in 10 minutes. It is.

(Test Example 2)
An experiment was conducted in which sewage having an S-COD concentration of 15 ppm was placed in a beaker and heated with a heater.
The temperature was maintained by operating the heater switch every 10 to 20 minutes so that the temperature was maintained in the range of 85 ° C to 95 ° C.
And since the inside of the beaker was stirred by convection, it was manually stirred to supplement the stirring from time to time.

In this experiment, the following results were obtained.
(1) 10 minutes S-COD 380 ppm: Solubilization rate 96%
[Calculation formula of this solubilization rate: (380-15) ÷ 380 = 96]
(2) 30 minutes S-COD 790 ppm: Solubilization rate 98.1%
(3) 10-minute caustic soda used S-COD 1300 ppm: Solubilization rate 98.8%
(4) 10-minute caustic soda used S-COD 1800 ppm: Solubilization rate 99.1%

Conventionally, the S-COD was 430 ppm and the solubilization rate was 96.5% after being treated for about 6 hours, and in this experiment, it was confirmed that the treatment could be sufficiently performed in about 10 minutes.
Therefore, according to the present invention, if the temperature is 85 ° C. for 10 minutes, the solubilization rate can be increased to 90% or more and the sludge treatment capacity can be greatly improved.

(Test Example 3)
An experiment was conducted in which sewage having an S-COD concentration of 75 ppm was placed in a beaker and heated with a heater.
The temperature was maintained by operating the heater switch every 10 to 20 minutes so that the temperature was maintained in the range of 85 ° C to 95 ° C.
(1) 10 minutes S-COD 380 ppm: Solubilization rate 80%
(2) 10 minutes using caustic soda S-COD 1300ppm: Solubilization rate 94%
In this experiment, it was found that when caustic soda was used, the S-COD value was increased as the temperature became higher, and a great effect could be expected.

(Test Example 4)
An experiment was conducted in which sewage having an S-COD concentration of 15 ppm was put in a container, and the temperature was simply increased to use a thermophilic bacterium.

The results are as follows: (1) Solubility is 10% when treated at 20 ° C for 48 hours.
(2) When treated at 50 ° C for 48 hours, the solubilization rate is 28%
(3) Solubilization rate is 30% when treated at 70 ° C for 48 hours
(4) When treated at 80 ° C for 48 hours, the solubilization rate is 30%
Met.

In addition, when the case of mesophilic bacteria was examined for reference, the result was as follows: (5) When treated at 20 ° C for 48 hours, the solubilization rate was 3%
(6) When treated at 80 ° C for 1 hour, the solubilization rate is 15%
(7) When treated at 80 ° C for 24 hours, the solubilization rate is 15%
(8) Solubilization rate is 15% when treated at 80 ° C for 48 hours
Met.

In this experiment, even when the thermophilic bacterium was treated at 80 ° C for 48 hours, the solubilization rate was only 30%, and in the case of mesophilic bacteria, 15% when treated for 1 hour. The value did not change no matter how many hours later.
Therefore, in the microbial treatment, even if the temperature is raised, the solubilization rate cannot be increased, and if the temperature is further increased, the solubilization rate is decreased, so that the solubilization rate is lowered.

(Test Example 5)
A comparative experiment was conducted in which sewage having an S-COD concentration of 15 ppm was placed in a container and the change in S-COD at low and high temperatures was examined.
As a result, S-COD and solubilization rate were as follows.

Temperature range With or without caustic soda S-COD (ppm) Solubilization rate (%)
(1) Before treatment 75
(2) 25-35 ° C 68
(3) 25-35 ° C using caustic soda 72
(4) 35-45 ° C 69
(5) 35-45 ° C using caustic soda 72
(6) 45-55 ° C 110 31.8
(7) 45-55 ° C using caustic soda 230 67.3
(8) 55-65 ° C 230 67.3
(9) 55-65 ° C using caustic soda 240 68.7
(10) 65-75 ° C 270 72.2
(11) 65-75 ° C using caustic soda 340 77.9
(12) 75-85 ° C 290 74.1
(13) 75-85 ° C using caustic soda 360 79.1
(14) 85-95 ° C 380 80.0
(15) 85-95 ° C using caustic soda 1300 94.2

From this experimental result, it was found that the solubilization rate is about 70% at 55 to 65 ° C. or more, and the effect can be sufficiently expected.
In addition, the solubilization rate was 80% unless the strength of caustic soda in the high temperature range of 85-95 ° C was used, but the solubilization rate can be greatly improved to 94.2% by using caustic soda. It was.

  The present invention is a treatment technique performed before the treatment with microorganisms in the microbiological treatment of sewage treatment, and the microbiological treatment performed after this is either a treatment with an aerobic microorganism or a treatment with an anaerobic microorganism. Even it can be used.

The flowchart which shows the process process of this invention. The typical longitudinal section side view of the device used for the present invention. The typical vertical side view of the apparatus of another aspect. Moreover, the typical vertical side view of the apparatus of another aspect. Moreover, the typical vertical side view of the apparatus of another aspect. Moreover, the typical vertical side view of the apparatus of another aspect. The typical longitudinal section side view of an apparatus different from the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mixing pipe 2 Sterilization tank 3 Heater 4 Pump 5 Water supply pipe 6 Return pipe 7 Microorganism refractory solid substance removal device 8 Water supply pipe 9 Water supply pipe 10 Sewage treatment tank 11 Water supply pipe 12 Pump 13 Stirring tank 14 Water supply pipe 15 Pump 16 Mixing Pipe discharge pipe 17 Water supply pipe 18 Pump 19 Heater 20 Air injection pipe 21 Stirring circulation tank 22 Stirrer 23 Stirring motor G Raw water D Sewage W Water S Sewage treatment system

Claims (10)

In the microbiological treatment method of sewage, if the flowability of the raw sewage is low, add water to the raw sewage in the stirring tank and dilute the BOD concentration to about 10,000 ppm or less before introducing it into the stew tank. While stirring the sewage in the stirring tank,
The stirred sewage is introduced into a simmering tank, and the sewage is heated to adjust the temperature to 55 ° C to 98 ° C.
After the sludge is in a solubilized state in the simmering tank, the sewage simmering treatment method is characterized in that the sewage sewage is transferred to a microorganism decomposition process. In the microbiological treatment method of sewage, if the flowability of the raw sewage is low, add water to the raw sewage in the stirring tank and dilute the BOD concentration to about 10,000 ppm or less before introducing it into the stew tank. While stirring the sewage in the stirring tank,
The stirred sewage is introduced into a simmering tank, and the sewage is heated to adjust the temperature to 55 ° C to 98 ° C.
After the sludge is in a solubilized state in the simmering tank, the sewage sewage is passed through the mixing pipe together with the injected air, and then mixed in the mixing pipe and then transferred to a decomposition process by microorganisms. Sewage simmering treatment method. The stirring method of the sewage in the stirring tank is a stirring circulation in which the sewage in the stirring tank is drawn out and pumped and passed through the mixing pipe, mixed in the mixing pipe and then returned to the stirring tank. The sewage boiling method according to claim 1 or 2. The method of stirring the sewage in the stirring tank is to draw out the sewage in the stirring tank and pump it, pass it through the mixing pipe with the injected air, mix in the mixing pipe, and then return to the stirring tank. The method for stewing sewage according to claim 1 or 2, wherein the process is a stirring circulation. The sewage boiling method according to claim 1 or 2, wherein the sewage stirring method in the stirring tank stirs the sewage in the stirring tank at a high speed. The method for stirring sewage in the agitation tank is the same as the method for agitation of sewage in the agitation tank. The sewage in the agitation tank is extracted and pumped and passed through the mixing pipe and mixed in the mixing pipe. The sewage simmering treatment method according to claim 1 or 2, wherein the agitation circulation returning to the agitation tank and sewage in the agitation tank are combined at high speed. The sewage simmering treatment method according to any one of claims 1 to 6, wherein the temperature of the sewage in the agitation tank is adjusted to 55 ° C to 98 ° C when stirring in the agitation tank. The method for stirring sewage in the stirring tank is to stir the sewage in the stirring tank at a low speed for several minutes while adjusting the temperature to 55 ° C to 98 ° C, and then pulls out the sewage in the stirring tank. 3. The method for simmering sewage according to claim 1 or 2, wherein stirring circulation is carried out by pumping and passing through the mixing pipe, mixing in the mixing pipe and then returning to the stirring tank. The sewage is stewed according to any one of claims 2 to 8, wherein the microbial hard-to-decompose solids contained in the sewage are removed before passing the sewage through the first mixing pipe. Processing method. 10. The method for simmering sewage according to any one of claims 1 to 9, wherein sodium hydroxide, a surfactant or an enzyme agent is added to sewage during or before stirring.

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