JP3445464B2 - Waste treatment method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waste treatment method for treating liquid organic wastewater and solid organic waste that can utilize the energy generated during methane fermentation treatment.

[0002]

Conventionally, human waste sewage such as human sewage and septic tank sludge, liquid organic sewage such as livestock excrement, agricultural and marine products and food processing wastewater are subjected to biological nitrification denitrification treatment, and sludge is separated into solid and liquid. Methane gas generated by methane fermentation treatment by anaerobic methane fermentation treatment with solid waste containing organic waste such as kitchen garbage and kitchen waste and biological nitrification denitrification treatment of liquid content with organic wastewater There is known a waste treatment method in which liquefied organic sewage and wastes are comprehensively treated by using waste water for processing energy by using it for power generation and by utilizing waste heat to progress methane fermentation.

By the way, solid waste such as raw garbage is mainly composed of carbohydrates that are easily decomposed by methane fermentation, but the carbon / nitrogen ratio is 30 and the optimum ratio for methane fermentation treatment is 20. Compared with nitrogen content. On the other hand, the sludge after biological nitrification and denitrification treatment of liquid organic wastewater such as human waste water has a high carbon / nitrogen ratio of 5 and nitrogen, and also contains a large amount of protein and fat, so it is a solid waste. As a result, it cannot be digested well by methane fermentation treatment. Therefore, the conventional waste treatment method described above combines the sludge after the biological nitrification denitrification treatment and the solid waste in advance before the methane fermentation treatment to obtain a good carbon / nitrogen ratio of carbohydrates, proteins and fats. The efficiency of the methane fermentation process is being improved with a good ratio of minutes.

[0004]

However, liquid organic sewage such as human waste sewage generally contains a large amount of nitrogen compounds and phosphorus compounds, and also contains a large amount of organic substances due to COD and BOD. In the waste treatment method of No. 2, the separated water obtained by separating the sludge after the biological nitrification denitrification treatment cannot be treated by the biological nitrification denitrification treatment, and COD
Since pollutants such as hardly decomposable soluble organic substances and phosphorus compounds remain due to nitrogen, it is possible to perform nitrogen treatment by advanced treatment such as coagulation treatment with a coagulant, membrane separation, or adsorption treatment with activated carbon. It is necessary to remove the compound, the phosphorus compound, and the organic substances caused by COD and BOD.

In the case of membrane separation or adsorption treatment with activated carbon, many pollutants remain, so that the processing load becomes large and maintenance of activated carbon and membrane becomes complicated.

Further, with ferric chloride as a flocculant generally used for flocculation treatment of phosphorus compounds together with hardly decomposable soluble organic substances caused by COD, the flocculation treatment is carried out after biological nitrification denitrification treatment and solidified. When liquid separation is performed and sludge is subjected to methane fermentation treatment with waste, aggregated iron phosphate in sludge is reduced and eluted again during anaerobic methane fermentation treatment, and biological nitrification denitrification is again performed. It will be returned to the biological treatment tank to be treated, and phosphate ions will gradually be concentrated in the system,
However, there is a problem that the treatment with ferric chloride may not be completed.

In view of the above problems, it is an object of the present invention to provide a waste treatment method capable of treating organic wastewater and organic waste efficiently and easily.

[0008]

A method for treating waste according to claim 1 is a method for solid-liquid separation of a fermented product obtained by subjecting a biodegradable solid organic waste to a methane fermentation treatment. In the waste treatment method of treating the liquid organic sewage and biological nitrification denitrification treatment, solid-liquid separation into coagulated sludge and treated water by adding an inorganic coagulant after the biological nitrification denitrification treatment,
When the aggregated sludge is mixed with the fermentation-treated product and then solid-liquid separated, and when the aggregated sludge is mixed with the fermentation-treated product.
In addition, the pH is controlled to be acidic . Then, after the biological nitrification denitrification treatment of the liquid organic wastewater, an inorganic coagulant is added to perform solid-liquid separation into coagulated sludge and treated water, and this coagulated sludge is a biodegradable solid organic waste. Is mixed with the fermented product obtained by methane fermentation treatment to perform solid-liquid separation, and the separated liquid is subjected to biological nitrification denitrification treatment with liquid organic wastewater, so that the remaining coagulation action of coagulated sludge is utilized. Since untreated pollutants are aggregated and separated by methane fermentation treatment, the treatment is highly efficient. In addition, the fermentation process after the methane fermentation process
The pH was controlled to be acidic when mixing the physical substance and the coagulated sludge.
Therefore, the remaining flocculating action of coagulated sludge works efficiently and
Contaminants that remain untreated in the ton fermentation process are effective
It is efficiently aggregated.

The waste treatment method according to claim 2 is a biological matter.
Resolvable solid organic waste obtained by methane fermentation treatment
The fermented product is solid-liquid separated, and the separated liquid is liquid organic.
Sewage and biological nitrification denitrification waste treatment method smell
Then, after the biological nitrification denitrification treatment, an inorganic coagulant was added.
Solid-liquid separation into coagulated sludge and treated water.
After mixing with the fermented product, solid-liquid separation is performed,
When mixing mud with the fermented product, add an inorganic coagulant.
It is something to add . Then, the liquid organic wastewater is treated with biological coagulation denitrification and then treated with coagulated sludge by adding an inorganic coagulant.
Solid water is separated into water and the coagulated sludge is biodegradable.
Fermentation obtained by methane fermentation treatment of organic waste in the form of methane
It is mixed with the treated material and solid-liquid separated, and the separated liquid is treated with liquid organic contamination.
Because of the biological nitrification and denitrification treatment with water, the coagulated sludge remains
Untreated pollution in methane fermentation treatment using the coagulation effect of
The substance is coagulated and separated, so that it is processed with high efficiency.
In addition, when mixing coagulated sludge with fermentation products,
It is to add a collecting agent. And coagulated sludge and fermentation
In order to add a separate inorganic coagulant during mixing with the
High levels of residual pollutants not treated in the tongue fermentation process
Agglomerated processed every highly organic soluble sewage and organic waste is processed.

The waste treatment method according to claim 3 is
In the waste treatment method described in 2 , when the coagulated sludge is mixed with the fermentation treated product, the pH is controlled to be acidic. Then, since the pH is controlled to be acidic when the fermented product after the methane fermentation treatment and the coagulated sludge are mixed, the residual coagulation action of the coagulated sludge efficiently acts and remains without being treated in the methane fermentation process. Pollutants are efficiently aggregated.

The waste treatment method according to claim 4 is the waste treatment method according to any one of claims 1 to 3.
Solid-liquid content in excess sludge and separated water after biological nitrification and denitrification
Separate the excess sludge from organic waste and methane fermentation
Then, an inorganic coagulant is added to the separated water and treated with coagulated sludge.
It is solid-liquid separated into water. And liquid organic
After the biological nitrification and denitrification treatment of sewage, it becomes excess sludge and separated water.
Solid-liquid separation, surplus sludge is treated with organic waste and methane fermentation
Then, an inorganic coagulant is added to the separated water to obtain coagulated sludge and treated water.
Solid-liquid separation into a solid form that can biodegrade this coagulated sludge.
Fermented product obtained by methane fermentation treatment of organic waste
Solid-liquid separation by mixing with the liquid, and the separated liquid is mixed with liquid organic wastewater.
Physical sludge and organic waste for nitrification and denitrification
The carbon / nitrogen ratio during methane fermentation is good by mixing with
The ratio becomes favorable, the methane fermentation process proceeds efficiently, and the organic wastewater and the organic waste are treated highly efficiently .

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The configuration of an embodiment of the waste treatment method of the present invention will be described below with reference to FIG.

In FIG. 1, reference numeral 1 is a first residue removing means, and this first residue removing means 1 is constructed by combining screens and screw presses having a mesh size of about 1 mm in multiple stages. , To remove impurities mixed in human waste as organic wastewater. Further, 2 is a second residue removal means, and this second residue removal means 2 is configured similarly to the first residue removal means 1 and is mixed in the septic tank sludge as organic wastewater. Remove residue and contaminants. The removed residue and foreign substances are molded into pellets and processed into solid fuel, building materials, etc., or incinerated.

The second residue residue removing means 2 is connected to the residue residue separating means 3. The residue separation means 3 is
The septic tank sewage, from which the scum residue and impurities have been removed from the septic tank sludge by the second scum residue removing means 2, can flow in.

Further, the first refuse residue removing means 1 is connected to a biological treatment means 4 for performing biological purification treatment on the raw sewage wastewater obtained by removing impurities from the human waste by a biological digestion denitrification reaction. The biological treatment means 4 is aerobic because it has a structure for producing a nitrification / denitrification reaction in one tank, a tank for denitrification treatment and a tank for nitrification treatment, and an aeration means. A configuration in which a tank for treating aerobic microorganisms with microorganisms is added may be used.

The biological treatment means 4 is connected to a sludge separation means 5 for solid-liquid separating the excess sludge from the biological treatment liquid after the biological nitrification and denitrification treatment. This sludge separating means 5 separates excess sludge from the biological treatment liquid by filtration separation using a screen or a membrane, sedimentation separation processing, centrifugal separation processing, etc., and returns it to the residue separation means 3 to join the septic tank wastewater. . Then, the residue residue separating means 3 separates the residue and impurities remaining without being separated and removed by the second residue removing means 2 into sludge and stock solution, and the stock solution is provided to the biological treatment means 3. The undiluted solution is biologically digested and denitrified together with the human waste sewage from which contaminants have been removed by the biological treatment means 3.

Further, the sludge separating means 5 is connected with a coagulating means 6 for coagulating the separated water separated by the sludge separating means 5 by adding an inorganic coagulant such as ferric chloride. There is.

Further, the aggregating means 6 includes the aggregating means 6
The first solid-liquid separation means 7 is connected to separate the coagulation treatment liquid that has undergone the coagulation treatment into a coagulation sludge and treated water by filtration separation using a screen or a membrane, sedimentation separation treatment, centrifugal separation treatment, or the like. The treated water is discharged outside the system such as discharged.

On the other hand, 11 is a waste pretreatment means, and this waste pretreatment means 11 disintegrates wastes including biodegradable organic wastes such as raw wastes and agricultural and marine wastes. It is composed of a crushing device for crushing, and a metal removing device for magnetically sorting while washing the crushed material in which waste is crushed by this crushing device.

Further, the dust pretreatment means 11 includes the preparation means 12
Are connected. The preparation means 12 is connected with a residue transfer means 13 for transferring the residue, foreign matters, and excess sludge separated by the residue separation means 3 and feeding them into the preparation means 12. Then, the preparation means 12 is the residue, the contaminants and the excess sludge conveyed by the residue transfer means 13 and the crushed waste from the pretreatment means, while appropriately adding water, for example, about It is heated to 55 ° C. and mixed with stirring to prepare a tempered product.
Note that steam may be used for adding water and heating. By using steam, it is not necessary to add water and heat it separately by heating means, so that heating can be performed efficiently.
Can be mixed with stirring.

Further, the preparation means 12 is connected to a methane fermentation means 14 for subjecting the prepared tempered material to methane fermentation treatment. The methane fermentation means 14 appropriately stirs at a temperature of, for example, 55 ° C. to methane-ferment an organic substance with methane bacteria or the like. The methane fermentation means 14 is provided with a methane gas recovery means (not shown) for recovering the generated methane gas. The recovered methane gas is used for power generation and the like, and is used as operating energy when treating organic sewage such as human waste and sewage.

Further, the methane fermentation means 14 is connected to a mixing means 15 for stirring and mixing the fermented product obtained by the methane fermentation treatment and the agglomerated sludge separated by the first solid-liquid separation means 7. ing. The mixing means 15 has a pH control means (not shown) for measuring the pH of the mixture of the fermented product and the coagulated sludge and controlling the pH in an acidic atmosphere, preferably pH 5 to 5.5, and an inorganic material such as ferric chloride. A coagulant adding means for adding a coagulant is provided.

Further, the mixing means 15 is a second solid-liquid separation for solid-liquid separation of the agitated and mixed mixture by various solid-liquid separation methods such as filtration separation using a screen or a membrane, sedimentation separation treatment, centrifugal separation treatment and the like. Separation means 16 is connected. Then, the separated liquid separated by the second solid-liquid separating means 16 is returned to the biological treatment means 4 by the separated liquid returning means 17,
The solid content is formed into pellets and processed into solid fuel, building materials, or incinerated. The separated liquid returning means 17
May be returned to the residue separation means 3.

Next, the operation of the above embodiment will be described.

First, the human waste is made to flow into the first raw residue removing means 1 to be separated into solid waste and liquid waste sewage, and the waste sewage is made to flow into the biological treatment means 4.

On the other hand, the septic tank sludge is removed by the second residue removing means 2
To separate into a solid residue and a liquid septic tank wastewater, and the septic tank wastewater is allowed to flow into the residue separation means 3. Then, the undiluted solution that has been subjected to solid-liquid separation by the waste residue separating means 3 is allowed to flow into the biological treatment means 4, and the undiluted solution is subjected to biological nitrification denitrification treatment together with the excrement sewage in the biological sewage wastewater and the undiluted solution. A part of the organic substances, nitrogen compounds, and phosphorus compounds that contribute to the mixed BOD are treated.

After that, the biological treatment liquid after the biological nitrification and denitrification treatment is made to flow into the sludge separation means 5 and separated into excess sludge and separated water by filtration separation by a screen or a membrane or sedimentation separation treatment. To do. Then, the excess sludge is returned to the scum residue separating means 3, and the separated water is flown into the coagulating means 6.

Next, the separated water that has flowed into the flocculation means 6 is
For example, an inorganic flocculant such as ferric chloride is added, and in addition to the organic substances and nitrogen compounds that contribute to BOD remaining in the separated water, the organic substances and phosphorus compounds that contribute to COD are coagulated. After that, the coagulation-treated coagulation treatment liquid flows into the first solid-liquid separation means 7, and is solidified into coagulation sludge and treated water by various solid-liquid separation methods such as filtration separation using a screen or a membrane and sedimentation separation treatment. Separate the liquid. Then, the treated water is discharged outside the system.

On the other hand, solid waste containing biodegradable organic waste such as raw waste, agricultural and marine waste, sludge, etc. is thrown into the shredder of the waste pretreatment means 11 for disintegration and disintegration. The crushed crushed material is cleaned by a metal removing device and magnetically separated to remove the metal.

Then, a crushed material of the crushed waste after magnetic selection is put into the preparation means 12, and at the same time, a residue transfer means.
The residue, contaminants and excess sludge separated by the residue separation means 3 are introduced via 13. After that, the crushed material of the waste and the residue, the impurities and the sludge are stirred and mixed while being heated to about 55 ° C. using steam to prepare a tempered material. By stirring and mixing the crushed material of this waste with the residue, contaminants and sludge, the viscosity of organic residues adhering to the residue, contaminants and sludge decreases, and it is solubilized in the warm water generated by condensation of steam. . After that, the refined material prepared by stirring and mixing for a predetermined time is allowed to flow into the methane fermentation means 14 and, for example, at 55 ° C.
The organic substance is subjected to methane fermentation treatment with methane bacteria and the like by appropriately stirring at. The methane gas generated by the methane fermentation process is recovered by the methane gas recovery means and used for power generation and the like, and is used as operating energy for the treatment of organic wastewater such as human waste system wastewater and waste.

Next, the fermented product obtained by subjecting the refined product to methane fermentation by the methane fermentation means 14 is allowed to flow into the mixing means 15 and mixed with the agglomerated sludge separated by the first solid-liquid separation means 7 by stirring. During this stirring and mixing, while the inorganic coagulant such as ferric chloride is added by the coagulant adding means, the pH is controlled by the pH control means so that the pH is acidic, preferably 5 to 5.5, and the coagulation treatment is performed. . In this coagulation treatment, the coagulation sludge introduced from the first solid-liquid separation means 7 has the coagulation action of the inorganic coagulant added by the coagulation means 6, and therefore the remaining coagulation action and new addition are newly added. A coagulation treatment occurs due to the coagulation action of the inorganic coagulant.

After that, the second solid-liquid separation means 16 performs solid-liquid separation into a separated liquid and a solid content by various solid-liquid separation methods such as filtration separation using a screen or a membrane, sedimentation separation treatment, and centrifugal separation treatment. To do. Then, the separated liquid is returned to the biological treatment means 4 by the separated liquid returning means 17 and merged with the human waste water and the stock solution to be biologically treated, and the solid content is formed into pellets by solidification into solid fuel or building materials. RDF processing to
Incinerate.

By the way, wastes containing organic wastes such as food wastes are mainly composed of carbohydrates which are easily decomposed by methane fermentation, but the carbon / nitrogen ratio is 30 and the optimum ratio of methane fermentation treatment. Nitrogen content is low compared to 20. On the other hand, sludge after biological treatment of human wastewater, which is organic wastewater, has a high carbon / nitrogen ratio of 5 and a large amount of nitrogen, and also contains a large amount of protein and fat, and thus was subjected to methane fermentation treatment as solid waste. Can't digest well. However, in the above-described embodiment, waste such as raw garbage and excess sludge are mixed to obtain a good carbon / nitrogen ratio, and the ratios of carbohydrates, proteins and fats are also improved, and methane fermentation treatment is performed. Can proceed efficiently.

As described above, the above embodiment is the first
Sewage sewage and septic tank sewage from which the sewage residue and contaminants have been separated by the second residue removal means 1 and the second residue removal means 2 are biologically nitrified and denitrified by the biological treatment means 4 to perform sludge separation means. 5, the excess sludge is separated, and further, the aggregating means 6 performs an aggregating treatment using an inorganic aggregating agent, and the first solid-liquid separating means 7 performs solid-liquid separation into aggregating sludge and treated water and separates them. A methane fermentation process is performed on the residue, the contaminants and the surplus sludge, and the waste containing the biodegradable organic waste by the methane fermentation means 14, and the processed fermentation processed product is mixed by the first means by the mixing means 15.
Is mixed with the coagulated sludge that has been subjected to the solid-liquid separation by the solid-liquid separation means 7 and the coagulation treatment is performed again by utilizing the remaining coagulation action of the coagulated sludge
Solid-liquid separation is performed by the second solid-liquid separation means 16, and the separated liquid is returned to the biological treatment means 4.

Therefore, the organic matters adhering to the residue, contaminants and sludge separated from the human waste water are digested by the methane fermentation treatment together with the organic waste, and the organic residue is discharged to the outside of the system with the organic materials attached. The methane fermentation treatment can be carried out efficiently without being treated, and the treatment cost can be reduced by effectively utilizing the methane gas generated by the methane fermentation.

Further, by utilizing the residual aggregating action of the inorganic aggregating agent added after the treatment of the human waste water, phosphorus compounds such as phosphate ions which have not been treated in the methane fermentation treatment and hardly decomposed soluble organic substances due to COD, etc. Since the pollutants of (1) are aggregated and separated, it is possible to treat human wastewater and wastewater with high efficiency.

Further, since the separated liquid which is solid-liquid separated by the second solid-liquid separation means 16 is returned to the biological treatment means 4 by the separated liquid returning means 17, organic matter in the untreated separated liquid by methane fermentation is And contaminants such as phosphate and ammonium ions can be highly purified by biological treatment and coagulation treatment in the subsequent stage by using the energy obtained by methane fermentation, and efficiently and highly efficiently produce human waste water and waste. It can be processed.

Further, before the coagulation means 6 coagulates the biologically treated treatment liquid, the sludge separation means 5 separates excess sludge and returns it to the residue separation means 3 to separate the separated water. Since the coagulation treatment is carried out by the method described above, the inorganic coagulant can act only on the contaminants that cannot be treated by the biological treatment and are dissolved and left, and the addition amount of the inorganic coagulant can be reduced. It is mixed with the organic waste through the methane fermentation process, and the carbon / nitrogen ratio of the methane fermentation process becomes a good ratio, the methane fermentation process can proceed efficiently, and the human sewage sewage and the sewage effluent can be efficiently processed. Can handle waste.

Further, when the waste is treated, the methane fermentation treatment is not directly carried out, but the waste pretreatment means 11 is first crushed and then crushed and mixed by the preparation means 12, and the methane fermentation treatment is carried out. Even if contaminants that are difficult to biodegrade are mixed in, by crushing the contaminants together with the organic waste to obtain a substantially uniform composition, solubilization of contaminants such as organic substances and methane in the subsequent mixing can be achieved. Fermentation processing can proceed efficiently.

In the above embodiment, the preparation means
Before subjecting the mixture prepared in 12 to methane fermentation treatment in the methane fermentation means 14, contaminants such as synthetic resin film, plastic, styrofoam, and glass, which are extremely difficult to biodegrade, may be separated and removed while washing. Then, the removed contaminants are, for example, separately molded into pellets to be solid fuel or subjected to RDF treatment such as building materials, or incinerated. According to this configuration, a substance that cannot be digested by the organism is not mixed during the methane fermentation treatment, and the methane fermentation treatment can be efficiently performed.

Separately, human waste and septic tank sludge are separated into
The waste residue removing means 1 and the second waste residue removing means 2 have been described as removing the waste residue and the contaminants, respectively. However, the waste material which is the organic wastewater in which the waste material, the septic tank sludge and the liquid waste are mixed in advance. In the case of system wastewater, after separating the scum residue, it is processed by various solid-liquid separation methods such as filtration separation using a membrane, sedimentation separation process, centrifugal separation process, coagulation separation process, etc. by the residue separation means 3. After that, the liquid content may be biologically treated, and the solid content may be added to the preparation means 12 for treatment. Further, the sewage system wastewater may be directly subjected to solid-liquid separation by the sewage residue separation means 3 without separating the sewage residue. According to these configurations, the configuration is simplified and the device can be downsized.

Further, although the description has been made by adding the inorganic coagulant in the mixing means 15, it is also possible to simply stir and mix the coagulated sludge and the fermented product. In addition, since the inorganic coagulant is added by the mixing means 15, the treatment can be performed to a higher degree.

The separation liquid separated by the second solid-liquid separation means 16 is returned to the biological treatment means 4 by the separation liquid returning means 17, but the separated separation liquid is separated from the human waste sewage. May be processed.

Then, the preparation means 12 is provided and mixed in advance before the methane fermentation treatment, but the methane fermentation means 14 directly disposes of the residues and contaminants from the residue separation means 3 and the pretreatment means 11. You may throw in a thing and process it.

Further, the description has been made by mixing the residue and the contaminants with the waste while heating with the preparation means 12, but it is also possible to simply mix without heating.

[0046]

[Example] 0.15 kg of excess sludge having a water content of 82% generated by nitrification and denitrification treatment at a human waste treatment plant, and raw slurries having a water content of 81% obtained by mixing and grinding vegetables, fruits, meat, fish, cooked rice, etc. 1.2 kg was mixed and diluted with 1.32 kg water to prepare a mixture having a TS concentration of about 10%. The excess sludge and the coagulated sludge were set to have a dry matter weight ratio of 8: 2.

Then, 55 minutes of the mixture was placed in an acrylic methane fermenter having a digestion period of 50 days and an actual volume of 5 liters.
The mixture was allowed to stay at 10 ° C. for 10 days, and methane fermentation was continuously processed by a gas stirring method. The water quality of the fermented product after 30 days is shown in Table 1.

[0048]

[Table 1] Further, 1 kg of the fermented material having the properties shown in Table 1 was obtained by coagulating and separating with ferric chloride the separated water from which excess sludge had been separated after nitrifying and denitrifying treatment at a human waste treatment plant to obtain a water content of 78%. 0.01 kg of coagulated sludge was thoroughly mixed with stirring, and solid-liquid separation was performed by centrifugation to measure the water quality of the supernatant. The results are shown in Table 2.

[0049]

[Table 2] From the results shown in Tables 1 and 2, it can be seen that the coagulated sludge coagulated by the coagulation means 7 has a sufficient coagulation action and can be further coagulated.

On the other hand, when mixing the fermented product and the coagulated sludge, the pH was appropriately varied with hydrochloric acid, the supernatant was collected by centrifugation, and the water quality was measured. The results are shown in Table 3.
And shown in FIG.

[0051]

[Table 3] From the results shown in Table 3 and FIG.
It can be seen that controlling the acidic atmosphere of No. 5 reduces the phosphate ion concentration, that is, the phosphate ions are aggregated by the aggregation action of the aggregated sludge.

[0052]

According to the waste treatment method of the first aspect of the present invention, liquid organic wastewater is subjected to biological nitrification and denitrification treatment, and then an inorganic coagulant is added to perform solid-liquid separation into coagulated sludge and treated water. , This coagulated sludge is mixed with a fermentation product obtained by subjecting a solid organic waste that is biodegradable to methane fermentation to solid-liquid separation, and the separated liquid is liquid organic wastewater and biological nitrification. Since denitrification is performed, untreated pollutants are aggregated and separated by methane fermentation treatment by utilizing the residual aggregation action of the aggregated sludge, so that highly efficient treatment is possible. Also, methane fermentation treatment
When mixing the fermentation product and the coagulated sludge afterwards, make the pH acidic
Because of the control, the remaining coagulation action of coagulated sludge is efficiently
Dirt that acts and remains untreated in the methane fermentation process
The dyed substance can be efficiently aggregated.

According to the waste treatment method of claim 2 ,
Inorganic coagulant liquid-like organic wastewater after biological nitrification denitrification treatment
The agent is added to perform solid-liquid separation into coagulated sludge and treated water.
Methane is used as a solid organic waste that can biodegrade collected sludge.
Solid-liquid separation by mixing with fermentation products obtained by fermentation
The separated liquid is treated with liquid organic wastewater and biological nitrification and denitrification.
Therefore, the residual coagulation action of coagulated sludge is used to
Since untreated pollutants are aggregated and separated in the fermentation process,
It can be processed highly efficiently. Also, coagulated sludge and fermentation treatment
When mixing with a substance, because an inorganic coagulant is added separately,
Advanced pollutants that remain untreated by fermentation
Aggregation can be processed, it can handle highly organic soluble sewage and organic waste.

According to the waste treatment method of claim 3,
In addition to the effects of the waste processing method according to claim 2 Symbol placement, to control the pH to the acidic upon mixing of the fermentation processed material after the methane fermentation treatment and flocculation sludge agglomeration remaining aggregation sludge efficiently It acts and can efficiently aggregate residual pollutants that are not processed in the methane fermentation process.

According to the waste treatment method of claim 4,
In addition to the effect of the waste treatment method according to any one of claims 1 to 3, after liquid organic wastewater is treated by biological nitrification denitrification
Solid-liquid separation into excess sludge and separated water to remove excess sludge
Fermented waste and methane, and added inorganic coagulant to separated water
Solid-liquid separation into coagulated sludge and treated water.
Methane fermentation treatment of biodegradable solid organic waste
It is mixed with the fermented product obtained by
To treat liquid organic wastewater and biological nitrification denitrification
Methane fermentation treatment by mixing excess sludge and organic waste
The carbon / nitrogen ratio in the case of
The fermentation process can proceed , and organic wastewater and organic waste can be treated highly efficiently .

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of a waste treatment method of the present invention.

FIG. 2 is a graph showing the concentration of phosphate ions by adding ferric chloride at each pH.

[Explanation of symbols]

4 Biological treatment means 5 Sludge separation means 6 aggregation means 7 First solid-liquid separation means 14 Methane fermentation means 15 Mixing means 16 Second solid-liquid separation means 17 Separation liquid return means

Front Page Continuation (72) Inventor Hiroshi Sasaki 2-9, Surihori, Nishi-ku, Osaka-shi, Osaka Ataka Kogyo Co., Ltd. (56) Reference JP 10-216785 (JP, A) Japanese Patent Publication 1-25640 (JP, B2) JP-B-56-42272 (JP, B2) (58) Fields investigated (Int.Cl. ⁷ , DB name) C02F 3/28-3/34 C02F 11/00-11/20 B09B 1 / 00-5/00

Claims (4)

(57) [Claims] 1. A biodegradable solid organic waste
Solid-liquid separation of the fermented product obtained by methane fermentation treatment
Treatment of separated liquid with liquid organic wastewater and biological nitrification denitrification
In the waste treatment method, an inorganic coagulant is added after the biological nitrification denitrification treatment to coagulate.
Solid-liquid separation of collected sludge and treated water,
And solid-liquid separation after being mixed with enzyme treated, the aggregate sludge when to be mixed with the fermented product, pH
Waste disposal method and controls acidified. 2. A biodegradable solid organic waste
Solid-liquid separation of the fermented product obtained by methane fermentation treatment
Treatment of separated liquid with liquid organic wastewater and biological nitrification denitrification
In the waste treatment method, an inorganic coagulant is added after the biological nitrification denitrification treatment to coagulate.
Solid-liquid separation of collected sludge and treated water,
And solid-liquid separation after being mixed with enzyme treated, the aggregate sludge when to be mixed with the fermented product, waste processing method comprising adding an inorganic flocculant. 3. The waste treatment method according to claim 2 , wherein the pH is controlled to be acidic when the coagulated sludge is mixed with the fermented product. 4. After biological nitrification denitrification treatment, solid-liquid separation is performed into excess sludge and separated water, the excess sludge is subjected to methane fermentation treatment with organic waste, and an inorganic coagulant is added to the separated water. claims 1 to characterized in that solid-liquid separation and coagulation sludge treated water 3 Izu
Waste treatment method Re one described.