JP2003053395A - Integrated treatment equipment for garbage, night soil and organic sludge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique capable of extremely rationally performing an integrated treatment of organic wastes, such as night soil, septic tank and garbage with an extremely simple facility and rapidly manufacturing compost having a high fertilizer value. SOLUTION: This integrated treatment equipment for the garbage, night soil and septic tank sludge has a self-heat generation mixing vessel which is supplied with the organic sludge and garbage discharged from a treatment system for the night soil and septic tank sludge under supply conditions under which the temperature thereof can be raised higher by >=40 deg.C than the temperature in a treating vessel by only the biological oxidation heat of the organic matter and performs biooxidation, a sludge dewatering equipment which dewaters the treated sludge subjected to the biooxidation from this mixing vessel and a treatment equipment which mixes the dewatered separated water from the dewatering equipment with the night soil or the septic tank sludge and performs a biological nitrification and denitrification treatment.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for integrated treatment of night soil, septic tank sludge, and garbage with extremely simple equipment.

[0002]

2. Description of the Related Art Conventionally, a device as shown in FIG. 2 has been put into practical use, which integrally processes human waste, septic tank sludge, and garbage as a core device of methane fermentation. In the conventional integrated processing apparatus of FIG. 2, raw garbage 1 is supplied to a methane fermentation facility 2 for methane fermentation, and a generated methane gas-containing digested gas 4 is stored in a gas holder 5 and gas is stored in the fermentation facility 2. The separated sludge 5 separated from 4 is dehydrated by the sludge dehydrator 6, the dehydrated cake 7 is discharged out of the system, and the separated liquid 8 is supplied to the biological nitrification / denitrification device 9. On the other hand, the human waste and the septic tank sludge 10 are added with a coagulant 11 and concentrated by the screen concentrator 12, the concentrated sludge 13 is supplied to the methane fermentation equipment 2, and the separated liquid 14 is the biological nitrification and denitrification equipment 9 And is subjected to nitrification and denitrification treatment together with the separated liquid 8. The separated liquid is treated in the advanced treatment equipment 15, and then discharged as clean treated water 16 out of the system. Excess sludge 17 from the nitrification and denitrification device 9 is
It is returned to the position before the addition of the flocculant 11 of the pipe to the screen concentrator 12.

This conventional system is a state-of-the-art technology at the present time and is a rational system capable of integrally treating raw garbage, human waste, and septic tank sludge and recovering energy called methane gas. However, in terms of equipment costs, the equipment costs of the methane fermentation tank and the methane gas holder are relatively high, so there may be a disadvantage in terms of equipment costs unless a large amount of food waste is processed.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems of the prior art and very reasonably integrates organic waste such as human waste, septic tank sludge, kitchen refuse, etc. Compost that can be processed and has high fertilizer value,
It is an object to provide a technology that can be manufactured in a short time.

[0005]

According to the present invention, the above problems can be solved by the following means. (1) The organic sludge and food waste discharged from the treatment system of human waste and septic tank sludge are supplied under the supply condition that the temperature in the treatment tank can be raised by 40 ° C. or more only by the heat of biological oxidation of the organic matter. A self-heated stirring tank for oxidation, a sludge dewatering device for dehydrating the biologically oxidized treated sludge from the stirring tank, and dehydrated separated water from the dehydrator are mixed with human waste or septic tank sludge for biological nitrification and denitrification. An integrated treatment device for food waste, human waste, and septic tank sludge, which has a treatment device for performing nitrogen treatment.

(2) A solubilizer for physicochemically solubilizing the temperature-rising sludge in the self-heating stirring tank, and a pipe for returning the solubilized product from the solubilizer to the self-heating stirring tank. The integrated processing device according to (1) above. (3) A solubilizer for physicochemically solubilizing the surplus activated sludge of the biological nitrification and denitrification apparatus, and a pipe for supplying a solubilized product from the solubilizer to the self-heating stirring tank. The integrated processing device described in (1) above. (4) The integrated processing device according to (1), which has a pipe for allowing the biological nitrification and denitrification tank to absorb the exhaust gas from the self-heating stirring tank. (5) The integrated processing apparatus according to (1) above, wherein the slurry supplied to the dehydrator is provided with means for adding Mg or Fe ion source material.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment of the present invention will be described in detail with reference to FIG. The parts having the same functions as those shown in FIG. 1 are designated by the same reference numerals. In FIG. 1, a raw sludge 1, human waste, and a concentrated sludge 13 obtained by concentrating an organic sludge 10 generated from a septic tank sludge treatment system are supplied to a self-heating stirring tank 18 and mechanically stirred with an oxygen-containing gas 3. Aerate for 3 to 4 days. When the temperature of the feedstock is 20 ° C., the internal temperature of the stirring tank 18 is 60 to 70 due to the heat of biooxidation generated when the organic matter is mineralized without external heating using fuel such as petroleum. ℃
, So that a temperature rise of 40 to 50 ° C will occur 1
The conditions for supplying the organic sludge 10 and the stirring time are set.

As a result, the organic matter in the garbage 1 and the organic sludge 10 is oxidatively decomposed at a high speed in a high temperature aerobic state in a time significantly shorter than the time required for methane fermentation (usually about 15 days), It is made inorganic and the amount of SS is greatly reduced. Since the exhaust gas 19 containing ammonia is discharged from the stirring tank 18, this is blown into the biological nitrification and denitrification treatment device 9 of the human waste and the septic tank sludge 10 to dissolve the ammonia in water to biologically nitrify and denitrify. To process.

The self-heating stirring tank 18 is preferably a multi-stage series tank of 3 to 4 tanks instead of one tank in order to prevent a short pass. Air is sufficient as the oxygen-containing gas 3 to be used for aeration, but oxygen-enriched air or pure oxygen that can reduce the amount of exhaust gas and exhaust heat may be used. In order to reduce the heat radiation from the self-heating stirring tank 18 as much as possible, it is preferable to carry out heat insulation work.

There are the following two types of sludge discharged from the treatment system for human waste and septic tank sludge 10. 1) Septic tank sludge, separated sludge 13 obtained by separating SS content in human waste 10 with a screen concentrator 12 or the like. 2) Excess activated sludge 17 generated from biological nitrification and denitrification treatment step 9 of human waste and septic tank sludge 10.

These sludges are supplied to the self-heating stirring tank 18 described above. The supplied sludge is concentrated to increase the sludge concentration. That is, the excess activated sludge 17 is not directly supplied to the self-heated stirring tank 18, but the polymer coagulant 11 is added as in the case of FIG. 2 and concentrated by the screen 12 or the multi-disk dehydrator, After concentrating by a mechanical means such as a centrifugal concentrator or flotation, concentrated sludge 13 having a solid content concentration of preferably increased to 3% or more is supplied to a self-heating stirring tank 18. Excess activated sludge 17, septic tank sludge 1
Since it is difficult to concentrate 0 into a high concentration by the weight precipitation concentration method, it is preferable to apply the mechanical concentration means as described above.

Next, a high-molecular coagulant is added to the agitation tank outflow sludge 20 whose temperature has risen due to the heat of bio-oxidation generated at that time to make the organic matter inorganic by high-temperature bio-oxidation, and the coagulated sludge is fed to a screw press or the like. Dewatering is performed by the mechanical dehydrator 6 to obtain a low-moisture dehydrated cake 7 having a water content of 60% or less.

In the process of the high temperature bio-oxidative stirring process of the present invention, the pathogenic bacteria in the sludge are completely killed, and the organic matter which is easily decomposed is completely decomposed in the process of high temperature oxidation. It is a compost product that can be applied as it is to farmland, has no bad odor, has a earthy odor, and is safe in terms of hygiene. In addition, when dewatering sludge, when an iron-based coagulant or a magnesium compound is added, phosphorus becomes iron phosphate or magnesium ammonium phosphate (MAP).
As a result, a fixed compost can be manufactured. When compost is applied to compost containing immobilized phosphorus, phosphorus does not elute due to rainfall, so that the phosphorus absorption effect on plants is improved. Since phosphorus contained in ordinary compost is not fixed, phosphorus is eluted by rainfall and the phosphorus utilization rate of plants is poor.

Then, the dehydrated separated water 8 is caused to flow into the biological nitrification / denitrification device 9 in the treatment process of night sewage and septic tank sludge 10, and SS, nitrogen components (ammonia nitrogen, organic matter) in the dehydrated separated water 8 are introduced. Nitrogen) and COD are removed. The water obtained by the membrane separation unit 22 in the biological nitrification / denitrification treatment device 9 is usually sterilized and discharged after the COD is highly removed by the advanced treatment device 15 using activated carbon or the like. Excess activated sludge 17 is generated from the biological nitrification and denitrification process of human waste, septic tank sludge 10 and dehydrated separated water 8. Therefore, the activated sludge 17 is concentrated by the screen concentrator 12 and then supplied to the self-heating stirring tank 18. And biodegrade.

A known physicochemical solubilizer 21 for ozone oxidation, ultrasonic irradiation, oxidation with hypochlorous acid, oxidation with hydrogen peroxide, alkali treatment, mechanical grinding and the like of the concentrated sludge 13 in which surplus activated sludge is concentrated. When the sludge solubilization treatment is performed by the above method and then supplied to the self-heating stirring tank 18, the biodegradability of the solubilized sludge is improved, so that the mineralization rate is improved, and further, the biological calorific value can be increased, which is preferable. .
Alternatively, the excess activated sludge 17 may be physicochemically solubilized and then supplied to the biological denitrification apparatus 9, where the solubilized sludge is biologically decomposed.

Although the demand for compost varies greatly depending on the existing facilities, during the season when the demand decreases,
The amount of compost production can be reduced without reducing the amount of raw garbage and sludge received. That is, in FIG. 1, the temperature at which bio-oxidation in the self-heating stirring tank 18 is high (6
The sludge is extracted at a high temperature by ozone oxidization, ultrasonic irradiation, oxidation with hypochlorous acid, oxidation with hydrogen peroxide, alkali treatment, mechanical grinding, etc. After the solubilization treatment, it is returned to the self-heating stirring tank 18. As a result, the solubilized sludge whose biodegradability is remarkably improved is subjected to biooxidation, mineralized, and disappears. The sludge solubilization effect of the physicochemical solubilization treatment improves as the temperature rises, but in the present invention, since the temperature can be raised without artificial heating, the physicochemical solubilization treatment under high temperature conditions is applied. There are important effects that can be achieved.

The amount of sludge disappeared depends on the solubilization process (solubilization device 2
Since the amount of sludge supplied to 1) can be controlled arbitrarily, the compost production amount can be controlled according to the demand amount of the compost product. Therefore, it is not necessary to dispose of excess compost when demand for compost products is low.

[0018]

As described above, according to the present invention, the following excellent effects can be obtained. (1) Compared to a methane fermentation tank, it is much simpler and more compact, and it is possible to perform integrated treatment of food waste, human waste, and septic tank sludge.
Equipment costs can be reduced. (2) Since biooxidation heat can be generated from physicochemically solubilized sludge, the amount of self-heating increases, and high-temperature biooxidation can effectively proceed. (3) The sludge whose temperature has been raised by the heat of self-oxidation of the organic waste is subjected to physicochemical solubilization such as ozone and ultrasonic waves (the higher the temperature, the greater the solubilization effect). improves. (4) Since compost in which phosphorus is immobilized can be produced, the effect of phosphorus absorption by plants during fertilization can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of an integrated treatment apparatus for organic waste according to the present invention.

FIG. 2 is a block diagram of an example of a conventional integrated processing device.

[Explanation of symbols]

1 garbage 2 Methane fermentation equipment 3 Oxygen-containing gas (air) 4 Methane-containing digestive gas 5 Separation sludge 6 Sludge dehydrator 7 dehydrated cake 8 dehydrated separated liquid 9 Biological nitrification and denitrification equipment 10 Human waste, septic tank sludge 11 Flocculant 12 screen concentrator 13 Concentrated sludge 14 Separation liquid 15 Advanced processing equipment (activated carbon adsorption, etc.) 16 Treated water 17 Surplus activated sludge 18 Self-heating stirring tank 19 Exhaust gas (gas containing ammonia) 20 Stirring tank runoff sludge 21 Physicochemical solubilizer 22 Membrane separation unit 23 Gas holder

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Norio Yamada             11-1 Haneda Asahi-cho, Ota-ku, Tokyo Co., Ltd.             Inside the EBARA CORPORATION F-term (reference) 4D004 AA02 CA19 CC02 DA03 DA06                 4D040 BB02 BB22 BB52                 4D059 AA01 AA02 AA05 AA07 AA23                       BA03 BC02 BE07 BE26 BE38                       BE41 BE56 BK12 BK17 BK22                       BK30 CA14 CB27 DA01 DA08                       DA22 DA43 DA44 DA45 EA06                       EB16

Claims (5)

[Claims] 1. The organic sludge and food waste discharged from the treatment system of human waste and septic tank sludge are supplied under a supply condition capable of raising the temperature of the inside of the processing tank by 40 ° C. or more only by the heat of biological oxidation of organic matter. , A self-heating stirring tank for performing biological oxidation, a sludge dewatering device for dehydrating the biologically oxidized treated sludge from the stirring tank, and dewatered separated water from the dehydrating device are mixed with human waste or septic tank sludge for biological treatment. An integrated treatment device for food waste, human waste, and septic tank sludge, which has a treatment device for nitrifying and denitrifying treatment. 2. A solubilizing device for physicochemically solubilizing the temperature-raised sludge in the self-heating stirring tank, and a pipe for returning the solubilized product from the solubilizing device to the self-heating stirring tank. The integrated processing device according to claim 1. 3. A solubilizer for physicochemically solubilizing excess activated sludge of the biological nitrification and denitrification apparatus, and a pipe for supplying a solubilized product from the solubilizer to the self-heating stirring tank. The integrated processing device according to claim 1, wherein: 4. The integrated processing apparatus according to claim 1, further comprising a pipe for absorbing exhaust gas from the self-heating stirring tank into the biological nitrification denitrification tank. 5. Mg or Fe is added to the slurry supplied to the dehydrator.
The integrated processing apparatus according to claim 1, further comprising means for adding an ion source substance.