JP2001259582A - Method for simultaneous treatment of garbage and wastewater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To recycle resources and energy by saving the consumption of energy required for the treatment of garbage and domestic wastewater and generating energy. SOLUTION: This method for simultaneous treatment of garbage and wastewater comprises a garbage disposal process for crushing the garbage 20 such as kitchen refuse, a mixing process for mixing the crushed product 21 of the garbage produced in the garbage disposal process, a solid-liquid separation process for separating solid from the domestic wastewater accompanied by the crushed product 21 mixed in the mixing process by a solid-liquid separation device 2, and an anaerobic microorganism treatment process for treating the separated liquid 28 separated in the solid-liquid separation process by immobilized microorganisms in an anaerobic microorganism treatment tank 4. The separated solid 22 separated by the solid-liquid separation device 2 is led into a fermentation tank 7 to be fermented. The combustion heat of the fermentation gas is recovered to generate electricity, and the surplus heat can be used for heating the fermentation tank 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for simultaneous processing of garbage and wastewater, and more particularly to a method of simultaneous processing of garbage and wastewater for treating garbage such as kitchen garbage and domestic wastewater in the same facility. .

[0002]

2. Description of the Related Art Conventionally, the treatment of garbage and the treatment of domestic wastewater have been performed in different waste treatment facilities, and have been treated in separate processes. For example, as shown in FIG. 3, the garbage 20 is collected in the waste incineration facility 1 together with other solid waste.
5 is incinerated in a waste incinerator 16 and the incineration residue is landfilled. On the other hand, the domestic wastewater 19 is removed from solids such as sewage and the like by a solid-liquid separation equipment 2 generally comprising a screen provided at a sewage inlet of the sewage treatment facility 1 and then led to the sedimentation basin 3 to be suspended solids. After precipitation and removal
Aerobic microbial treatment in aeration tank 13 and final sedimentation basin 1
The contaminants are removed from the sewage by 4 and the harmful substances are removed by the final treatment equipment, sterilized, and then discharged to rivers and oceans. The activated sludge 24 collected in the final sedimentation basin 14 is returned to the aeration tank 13, but a part of the activated sludge is discharged from the final sedimentation basin 14 to the outside sludge treatment facility as surplus sludge 25. The discharged excess sludge 25 is converted into compost in some facilities, and the excess sludge 25 is usually supplied to an incinerator or a waste melting furnace 1 provided there.
The ash or the molten slag 27 that is treated and discharged at 7 or the like is provided for landfill or reuse.

[0003]

The above-mentioned conventional garbage is collected by a garbage truck together with other wastes and then incinerated at a garbage incineration facility. And the cost of transport increases, and kitchen waste is often wrapped in vinyl chloride film bags and discarded, and it is difficult to sort and collect them. There is a problem that dioxins are generated in the exhaust gas and are easily released into the atmosphere. There are also problems such as the odor of garbage pits and difficulty in securing land for landfill sites for incineration residues. In addition, domestic wastewater is subjected to aerobic microbial treatment and has the advantage of a short treatment time, but has a problem of high energy consumption for aeration for treatment and the like. Therefore, the method for simultaneous treatment of garbage and wastewater of the present invention solves the above-described problems, reduces energy consumption by treating garbage together with domestic wastewater, and furthermore, generates energy. It is an object of the present invention to provide means capable of recycling resource energy.

[0004]

[Means for Solving the Problems]

[0005] The method for simultaneous treatment of garbage and wastewater according to the present invention is characterized in that garbage is treated with microorganisms together with domestic wastewater without being incinerated. It has the following features.

A first characteristic means of the method for simultaneous treatment of garbage and wastewater of the present invention for the above object is a garbage treatment step of crushing garbage such as kitchen garbage, as described in claim 1. A mixing step of mixing the garbage pulverized matter generated in the garbage processing step with household wastewater, and a solid-liquid separation of the domestic wastewater mixed in the mixing step and accompanied by the garbage pulverized matter by a solid-liquid separation facility. The method comprises a separation step and an anaerobic microorganism treatment step of treating the separated liquid separated in the solid-liquid separation step with immobilized microorganisms in an anaerobic microorganism treatment tank.

[0007] The second characteristic means of the method for simultaneous treatment of garbage and waste water of the present invention for the above object is as described in claim 2, wherein the separation liquid is used in the anaerobic microorganism treatment step of the first characteristic means. It is characterized in that a physicochemical reaction step for removing the nitrogen component and the phosphorus component in the treated liquid after the microorganism treatment is added.

According to a third aspect of the method for simultaneously treating garbage and waste water of the present invention for the above object, a nitrogen component and a nitrogen component in the physicochemical reaction step of the second aspect are provided. The finishing and sterilization steps of contacting the treated solution after removing the phosphorus component with an oxidizing gas are added.

According to a fourth aspect of the present invention, there is provided a method for simultaneously treating garbage and waste water, the method comprising the steps of: The separated solids separated in the liquid separation step are introduced into a fermenter to decompose the separated solids, and the combustible gas generated in the fermenter is supplied to a power generation facility to be used as a fuel for power generation.

According to a fifth aspect of the method of the present invention for simultaneously treating garbage and wastewater, the first power generation facility of the fourth aspect is provided with a gas engine or a fuel. The first power generation facility is configured to generate electric power by using waste heat of the first power generation facility.

According to a sixth aspect of the present invention, there is provided a method for simultaneous treatment of garbage and wastewater, wherein the first power generation equipment according to the fourth or fifth aspect is provided. Alternatively, the fermenter is heated by waste heat of the second power generation facility.

According to the method for simultaneous treatment of garbage and wastewater according to the present invention, the release of dioxins into the atmosphere due to waste treatment can be suppressed, and at the same time, wastewater treatment can be performed. Energy savings,
Each has the following unique effects.

According to the first characteristic means, the garbage pulverized matter generated in the garbage disposal step is introduced into various wastewater treatment steps together with domestic wastewater, thereby eliminating the need to transport garbage by car. In addition, since there is no need to incinerate the garbage, the amount of incineration is reduced, and accordingly, generation of dioxins can be prevented. If the separated liquid obtained by separating most of the solid matter in the liquid in the solid-liquid separation step is introduced into the anaerobic microorganism treatment step, methane fermentation decomposition is performed by the action of the anaerobic microorganism.

[0014] According to the second aspect, the microbial treatment is carried out while performing the microbial treatment while exhibiting the operation and effect of the first aspect.
Nitrogen components and phosphorus components remaining in the separated solution after removing D and COD can be removed and recovered by an adsorption ion exchange reaction or the like.

According to the third aspect, in addition to the operation and effect of the second aspect, the oxidative decomposition and the bactericidal action of the residue after the anaerobic treatment can be performed at the same time. Can be easily reused.

According to the fourth characteristic means, while exhibiting the operation and effect of any of the first to third characteristic configurations,
The solid matter separated from the solid-liquid separation step is fermented, and the resulting combustible gas can be used as a fuel for power generation. That is, waste can be turned into energy resources.

According to the fifth aspect, in the operation and effect of the fourth aspect, the waste heat from the first power generation facility is supplied to the second power generation facility separate from the power generation facility. If power is generated, the generated energy can be used more effectively.

According to the sixth aspect, the operation and effect of the fifth aspect can be further enhanced. That is,
By heating the fermenter with waste heat from the power generation equipment, fermentation of the separated solids can be promoted without using other heat sources, and the energy generated can be more effectively used.
It is possible to further promote the generation of combustible gas (using medium and high temperature fermentation).

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the method for simultaneous processing of garbage and waste water according to the present invention will be described below with reference to the drawings. Note that the same elements as those described in the related art and elements having the same functions are denoted by the same reference numerals as in FIG. 3 and a part of the detailed description is omitted.

As shown in FIG. 1, the form of treatment of garbage and domestic wastewater by the method for simultaneous treatment of garbage and wastewater according to the present invention, as shown in FIG. The sewage treatment facility 1 is provided with a disposer 11 for crushing garbage such as garbage and discharging the garbage to the sewage system 10, and receiving and treating domestic wastewater accompanied by garbage garbage from the sewage system 10. Sedimentation and screen as solid-liquid separation equipment 2 for separating solid matter such as residue, and first sedimentation basin 3 (these are used for sedimentation and removal of residual solid matter in separated liquid 28 after solid matter is removed here). The sedimentation basin may be omitted.), An anaerobic microorganism treatment tank 4 for reducing BOD and COD as contaminants from the separated liquid 28 flowing out therefrom, and the separated liquid 28 is subjected to anaerobic microorganism treatment. BOD and C Nitrogen component remaining in the treated liquid 29 reduced in D the adsorption tower 5 for adsorbing and removing (NH _3, etc.) and phosphorus components (mainly phosphoric acid), after adsorbing and removing nitrogen component and a phosphorus component from said treated liquid A finishing treatment equipment 6 for contacting an oxidizing gas (such as ozone) with the treated liquid to carry out oxidative decomposition and sterilization treatment; a separated solid 22 separated from domestic wastewater by the solid-liquid separation equipment 2 and an anaerobic microorganism treatment tank 4 A fermenter 7 for fermenting a part of the sludge discharged from the final sedimentation tank 14 later, and a gas purifier 8 for purifying combustible gas mainly composed of methane gas generated in the fermenter 7.
And the first power generation facility 9 for generating power using the purified combustible gas
A and a second power generation facility 9B that generates steam by generating waste heat to generate power.

In the sewage treatment facility 1 described above, FIG.
As shown in (1), garbage 20 is pulverized by a disposer 11 provided in each household to form pulverized garbage 21 (garbage disposal step), and discharged to the sewer 10 together with domestic wastewater 19 (mixing step). On the other hand, in the sewage treatment facility 1, solids in the water to be treated received from the sewage 10 are removed by a screen 2A as a solid-liquid separation facility 2 (separation step). The separated liquid 28 from which solid matter has been removed is introduced into the anaerobic microorganism treatment tank 4 and subjected to microbial treatment to decompose BOD and COD mainly composed of organic substances in the separated liquid by immobilized microorganisms (anaerobic microorganism treatment step). ). In the treated liquid 29 after the microorganism treatment, the COD and BOD are reduced to a predetermined concentration, but the COD and BOD are introduced into the ion exchange column 5 and the remaining nitrogen component (mainly ammonia ion and the like) and phosphorus component (mainly phosphoric acid Ions) are removed using an ion exchange resin (physicochemical reaction step). The treated liquid from which the nitrogen component and the phosphorus component have been removed in this way is introduced into the finishing treatment equipment 6 and is brought into contact with an oxidizing gas such as ozone to simultaneously perform the oxidative decomposition of the remaining organic components and the sterilization treatment, thereby forming the trihalomethane. The generation is suppressed, and the treated water 30 is discharged to a river or supplied to the middle water supply 12 as raw middle water to recycle the treated water. Further, the separated solid matter 22 separated in the separation step is supplied to the fermenter 7 and is subjected to the methane fermentation treatment under heating together with the excess sludge 25 discharged from the anaerobic microorganism treatment step. By this fermentation treatment, the organic matter in the separated solid substance 22 is decomposed, and methane 23 is generated. Then, the sludge composed of the undecomposed residue is taken out of the fermenter 7 as the recovered sludge 26. The collected sludge 26 taken out is supplied to a composting device 34 and supplied to farmers as a soil improvement material for agricultural land.
It is also used as a soil improvement material for forests such as forests.

On the other hand, the fermentation gas 23 generated during the fermentation treatment contains methane as a main component (about 60% methane, about 40% methane).
% CO ₂ ), which is a flammable gas, and a gas purifying device 8
The fuel is supplied as fuel for the fuel cell 31 constituting the first power generation facility 9A via the (denitration device). The electric power generated by the fuel cell 31 responds to the electric power demand in the facility and, if a surplus is generated, is also supplied as electric power to surrounding areas. The high-temperature exhaust gas from the fuel cell 31 is sent to the second power generation facility 9B. In the second power generation facility 9B, steam is generated in the waste heat boiler 32 using the exhaust gas as a heat source, and the steam from the waste heat boiler 32 drives the steam turbine 33 axially connected to the generator to generate power. . Part of the steam or hot water from the power generation facility
It is used as a heat source for heating to fermentation temperature such as.

In the solid-liquid separation equipment 2, it is preferable that the size of the separated solid matter 22 is 0.5 mm or more. This is because it is desirable to make the openings fine in order to increase the solid content recovery rate in the separation liquid 28 as much as possible, but if it is too small, clogging and cleaning become difficult. The immobilized microorganisms that act on the separation liquid 28 in the anaerobic microorganism treatment tank 4 include a macromolecule-based entrapment method for entrapping and immobilizing anaerobic microorganisms, or a UASB method granulated by the anaerobic microorganisms themselves. And a method of attaching and fixing an anaerobic microorganism to a material having a lot of voids such as activated carbon and sponge. According to these methods, the microorganism concentration can be kept higher than that of the suspended microorganism method, so that the adverse reaction time for methane fermentation can be shortened. In this way, the BOD concentration in the sewage that has passed through the 0.5 mm screen is about 300 ppm, which is about 30 to 50% higher than the BOD of the conventional sewage, and the separated liquid 28 is transferred to the anaerobic microorganism treatment tank. Introducing to 4,
Economical treatment can be achieved by the action of immobilized microorganisms composed of anaerobic microorganisms. Then, the BOD concentration after the microorganism treatment is usually reduced to about 10% or less.

The filler used in the physicochemical reaction tower 5 uses zeolite or an ion exchange resin to remove cations such as NH ₄ ⁺ and PO ₄ ^{3+ in} the target liquid (water). Remove by function. In addition to the vapor ion exchange method, there is a crystallization method and the like, but this crystallization method is not general for dilute liquids. Liquid 2 before being introduced into this physicochemical reaction tower 5
9 has an NH ₄ ⁺ concentration of about 10 to 20 ppm,
The concentration of the PO ₄ ³⁺ component is approximately 7 ppm, and the concentrations of NH ₄ ⁺ and PO ₄ ^{3+ at the} outlet of the physicochemical reaction tower 5 are approximately 1 ppm and 0.5 ppm or less.

As described above, in the sewage treatment facility 1, energy is produced and power can be supplied using the energy. , While keeping the discharged water sufficiently clean
By treating sewage containing solids, energy can be created.

[Another Embodiment] An embodiment of a method for simultaneous treatment of garbage and wastewater according to the present invention, not shown in the above embodiment, will be described below.

<1> In the above embodiment, a waste heat boiler 32 that generates steam by waste heat from the fuel cell 31;
The example in which the second power generation facility 9B for generating power with the steam turbine 33 that rotationally drives the generator with the steam from the waste heat boiler 32 has been described, but the thermal efficiency of the fuel cell 31 is sufficiently increased. In such a case, the waste heat may be insufficient to generate steam, in which case the second power generation facility 9B may not be provided. When the second power generation facility 9B is not provided, the fuel cell 3
Exhaust from 1 can be used to heat the fermenter 7.

<2> In the above embodiment, an example was described in which the generator of the first power generation facility 9A was constituted by the fuel cell 31, but the generator is a gas engine that burns the fermentation gas 23. The generator may be a rotary drive type generator driven by.

<3> In the above embodiment, an example in which the fermenter 7 is heated using a part of the waste heat of the first power generation facility 9A or the second power generation facility 9B has been described. As a heat source for heating the tank 7, another heat source may be used.

<4> In the above embodiment, the first power generation facility 9A for generating power using the fermentation gas 23 from the fermentation tank 7 in the sewage treatment facility 1, and the waste heat of the first power generation facility 9A Although the example which provided the 2nd electric power generation equipment 9B which produces | generates by the above was demonstrated, The said 1st electric power generation equipment 9A may generate | occur | produce using other fuels, Is also good.

<5> In the above embodiment, the example in which the fermenter 7 is provided in the sewage treatment facility 1 has been described.
The fermenter 7 may be provided outside the sewage treatment facility 1. In this case, the fermenter 7 is preferably provided in a power generation facility.

<6> In the above embodiment, an example in which nitrogen / phosphorus removal treatment is performed by the physicochemical reaction tower 5 provided in the sewage treatment facility 1 has been described. May be provided outside the sewage treatment facility 1.

<7> In the above embodiment, the example in which the finishing treatment facility 6 is provided inside the sewage treatment facility 1 has been described. And sterilization treatment may be performed. For example, the sewage treatment facility 1 is small,
In some cases, it is effective to perform the sterilization treatment in a wide-area facility outside the sewage treatment plant 1. Also,
When the advanced treatment of the wastewater is not required, the finishing treatment equipment capacity may be omitted.

[0034]

As described above, according to the present invention,
By reducing energy consumption and generating energy, it has become possible to recycle resource energy.

Incidentally, reference numerals are written in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configuration of the attached drawings by the entry.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating the concept of a method for simultaneous processing of garbage and wastewater according to the present invention.

FIG. 2 is a flowchart showing an example of a processing procedure of a method for simultaneous processing of garbage and wastewater according to the present invention.

FIG. 3 is a flowchart illustrating an example of conventional waste and wastewater treatment.

[Explanation of symbols]

 2 Solid-liquid separation equipment 4 Anaerobic microorganism treatment tank 7 Fermentation tank 9A First power generation equipment 9B Second power generation equipment 19 Domestic wastewater 20 Raw garbage 21 Raw garbage crushed material 22 Separated solid 28 Separated liquid 29 Treated liquid

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C02F 1/50 540 C02F 1/50 560H 560 1/78 3/28 B 1/78 9/00 501E 3 / 28 502D 9/00 501 502J 502 502P 503F 503F 504A 503 504E 504 11/04 A H01M 8/00 Z 11/04 8/06 R H01M 8/00 B09B 3/00 ZABD 8/06 Z CF term (reference) 4D004 AA03 AC05 BA03 BA10 CA04 CA18 CA22 CC07 4D040 AA04 AA13 AA23 AA27 4D050 AA15 AB06 BB02 CA06 CA08 CA15 CA17 4D059 AA04 AA05 AA06 AA07 BA12 BE31 BE49 BK11 CA08 CA11 CA22 CA23 CA28 CB27 ACO02 5A02

Claims (6)

[Claims] 1. A garbage disposal step for crushing garbage (20) such as kitchen garbage, and a mixing step for mixing garbage crushed material (21) generated in the garbage disposal step with domestic wastewater (19); The crushed garbage (2) mixed in the mixing step
A solid-liquid separation step of solid-liquid separation of domestic wastewater (19) accompanied by 1) by a solid-liquid separation equipment (2), and a separation liquid (28) separated in the solid-liquid separation step are subjected to an anaerobic microorganism treatment tank ( 4) A method for simultaneous treatment of garbage and wastewater, comprising the step of treating an anaerobic microorganism with an immobilized microorganism in step 4). 2. The treated liquid (2) obtained by subjecting the separated liquid (28) to a microorganism treatment in the anaerobic microorganism treatment step.
9. The method for simultaneous treatment of garbage and wastewater according to claim 1, further comprising a physicochemical reaction step for removing nitrogen and phosphorus components in 9). 3. A treated liquid (29) after removing the nitrogen component and the phosphorus component in the physicochemical reaction step.
3. A method for simultaneous treatment of garbage and waste water according to claim 2, further comprising a finishing and sterilizing step of contacting the garbage with an oxidizing gas. 4. The separated solid matter (22) separated in the solid-liquid separation step is introduced into a fermentation tank (7) to decompose the separated solid matter (22), and the flammable fuel produced in the fermentation tank (7) is decomposed. The method for simultaneously treating garbage and wastewater according to any one of claims 1 to 3, wherein the reactive gas is supplied to the first power generation facility (9A) and used as a fuel for power generation. 5. The first power generation facility (9A) is configured by a gas engine or a fuel cell, and the second power generation facility (9B) generates power using waste heat of the first power generation facility (9A). Item 4. The method for simultaneous treatment of garbage and wastewater according to Item 4. 6. The method for simultaneous treatment of garbage and waste water according to claim 4, wherein the fermenter (7) is heated by waste heat of the first power generation facility (9A) or the second power generation facility (9B). .