JP2879199B2 - Organic waste mineralization system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a treatment system that enables non-polluting treatment and reuse of organic waste containing solid matter.

[0002]

2. Description of the Related Art Conventionally, the treatment of organic waste containing solids is mainly intended for the treatment of wastewater contained therein, and the treated liquid is discharged into rivers or the sea, and the exhaust gas is discharged into the atmosphere. Solid organic waste is obtained by decomposition, incineration, landfill, and the like by microorganisms. However, environmental pollution problems such as activated sludge are generated in the case of microbial decomposition, soot and harmful substances are generated in the case of incineration, treatment plants are short in landfills, and odors and water pollution are becoming more serious.

[0003]

SUMMARY OF THE INVENTION The present invention provides a system for decomposing organic waste, including solid waste, by decomposing the waste by a system independent of the outside world and reusing the product to thereby achieve pollution-free treatment. It is trying to get.

[0004]

In order to achieve the above object, a system according to the present invention comprises a means for converting solid organic substances contained in waste into a slurry, and a method for converting organic substances contained in the slurry into a wet oxidation vessel. It comprises means for oxidative decomposition and liquefaction at high temperature and pressure, and means for mineralizing the liquefied treatment liquid with a catalyst, and further includes a plant cultivation means utilizing the treatment liquid and exhaust gas generated from each of the above means. The wet oxidation container may include an air addition device and a stirring means, and the catalyst mineralization means promotes decomposition by circulating the treatment liquid to the catalyst using a high-temperature and high-pressure circulation pump. It also includes a system for collecting and reusing waste heat generated during the wet oxidation process.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a waste disposal system according to the present invention will be described in detail with reference to the drawings. As organic waste, solid and liquid forms such as garbage, human waste, paper, wood, organic industrial waste, and the like can be widely used.

FIG. 1 is a flow sheet of one embodiment of the processing system of the present invention. As for the organic waste, solids are crushed in a pretreatment container 1 having a crusher. Even when there is a large amount of solid matter, a waste liquid from a plant cultivation facility is added to form a slurry as described below. The generated slurry is preheated through the heat exchanger 8 and is transferred by the transfer pump 2 to the valve 9.
And then introduced into the wet oxidation container 3. In the wet oxidation container 3, after a predetermined amount of air is added by the compressor 4 to increase the oxidation efficiency, the slurry is heated to a high temperature (250 to
(300 ° C.), and the contained organic matter is oxidatively decomposed and liquefied. At the time of heating, the wet oxidation container 3 is a closed high-pressure container in order to prevent vaporization of water contained in the organic matter. When the concentration of the organic matter is high, the stirrer 5 can be used so that the organic matter and the air are sufficiently mixed.

The processing liquid liquefied in the wet oxidation vessel 3 is introduced into the catalytic reactor 6 which has been heated to the same conditions as the wet oxidation vessel 3 in advance by opening the valve 10 at the pressure in the wet oxidation vessel 3. You. In the catalyst reaction vessel 6, an organic substance is continuously and repeatedly reacted with a catalyst by using a high-pressure and high-temperature circulation pump 7 to decompose into an inorganic substance and an inorganic gas (carbon dioxide and nitrogen gas). In the embodiment, the catalytic reactor 6
Although the undecomposed matter from is circulated to the wet oxidation vessel 3 by a pipe, the treatment liquid can be circulated only by the catalytic reactor 6.

[0008] The advantage of this circulation system is that oxygen contained in the gas phase can be efficiently mixed into the processing solution during oxidative decomposition. Also, the reason why the wet oxidation vessel 3 and the catalyst reactor 6 are made independent is that the catalyst is sealed in the wet oxidation vessel in the conventional method, so that when high-concentration organic substances are treated, the organic substances adhere to the catalyst. And the function of the catalyst deteriorates.
This is to prevent this.

Since the mineralized treatment liquid contains components necessary for growing the plant, it is introduced into the plant cultivation facility 13 through the valve 11. In addition, in order to use inorganic gas (carbon dioxide and nitrogen gas) for plant growth,
It is introduced into the plant cultivation facility 13 via the valve 12.

The heat generated in the wet oxidation container 3, the catalytic reactor 6, and the piping system is all recovered and used in the heat exchanger 8 and the plant cultivation facility 13. In addition, drainage and garbage generated from the plant cultivation facility 13 are introduced into the pretreatment container 1, and after oxidative decomposition,
Reuse.

FIG. 2 shows a high-pressure and high-temperature circulating pump 7 necessary for realizing continuous processing which is one of the features of the present invention. The pump body can be divided into a lower lid 21 and an upper lid 22. . The rotation of the blade 23 for transferring the liquid
The rotation of the shaft 24 having the internal magnet 29 of the permanent magnet on one side is generated, and the rotation of the shaft 24 is generated by externally driving the electromagnetic closed stirrer 30 with a belt. The rotation of the blades 23 causes the lower lid 21 to rotate.
After the liquid is sucked up from the pipe at the center of the blade 23, the liquid is discharged from the pipe of the upper lid 22 by the rotational force of the blade 23. In order to center the shaft 24, a bearing 26 held by a snap ring 25 is used. In order to withstand a high-pressure and high-temperature environment, the lower lid 21 and the upper lid 22 are improved in sealing performance by using a packing 27 and are tightened by a hexagon nut 28.

Processing Example An example of a specific implementation result of the present invention will be described with reference to Table 1. Rabbit feces were used as a raw material of the organic waste, and the concentration of the organic matter was 20,000 ppm in COD (Cr) and 30,000 ppm in Kjeldahl nitrogen. This organic waste (0.5 liter) was placed in a vacuum-evacuated wet oxidation container 3 having an internal volume of 1 liter, and oxygen required for oxidation was added at 2.5 Mpa. The decomposition temperature was set at 320 ° C. and heating was performed for 30 minutes. The primary treatment in Table 1 shows the results of analysis of a conventional wet oxidation decomposition solution that does not use a catalyst. COD is about 80% and Kjeldahl nitrogen is about 98.8%, but ammonia and acetic acid are not. Many have been generated.

[Table 1]

Therefore, the primary treatment liquid was continuously reacted with the catalyst in the catalyst reactor 6 for 30 minutes in the same environment. As an example of the catalyst to be used, a catalyst in which noble metals such as ruthenium and palladium are supported on titania and alumina in the form of granules or pellets is used. However, the present invention is not limited to this. For example, a catalyst such as platinum or zeolite can be used. As a result, the COD is about 99.7
%, Kjeldahl nitrogen was decomposed by about 99.97%. In addition, only a small amount of the ammonia component was present, and most of the nitrogen content had been changed to nitrate nitrogen, which is necessary for plant growth. Furthermore, acetic acid was below the detection limit of the analyzer. In addition, when examining the gas components, in the primary treatment without using a catalyst, the carbon dioxide concentration is about 30%,
With the use of a catalyst, it has increased to about 50%. These results show how efficiently the system of the present invention can convert organic waste to inorganic.

In the embodiment of the present invention, a plant cultivation facility is used as a waste liquid and gas utilization facility. Specifically, a plant plant such as a vegetable or a fruit tree is used.
It can also be used in tropical botanical gardens and aquariums by utilizing waste heat. Further, if necessary, the nutrient solution and gas can be supplied to a greenhouse or a cultivation facility for open-field cultivation without using a complete closed cycle.

[0015]

As described above, the present invention treats organic waste containing solid matter in a system independent of the outside world, so it is a pollution-free treatment that does not cause environmental pollution. Since it contains components necessary for growth, it becomes a nutrient solution for plants, and the generated gas and waste heat can be effectively used, so that organic waste can be reused with less energy and space.

[Brief description of the drawings]

FIG. 1 is a flow sheet showing one embodiment of the system of the present invention.

FIG. 2 is an assembly view showing a high-temperature and high-pressure circulation pump used in the system of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Pretreatment container 2 Transfer pump 3 Wet oxidation container 4 Compressor 5 Stirrer 6 Catalytic reactor 7 High pressure high temperature circulation pump 8 Heat exchanger 9, 10, 11, 12 Valve 13 Plant cultivation facility 21 Lower lid 22 Upper lid 23
Rotating blade 24 Shaft 25 Snap ring 26
Bearing 27 Packing 28 Hex nut 29
Permanent magnet 30 Closed stirrer

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-78496 (JP, A) JP-A-54-38271 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B09B 3/00-5/00 C02F 11/08

Claims (5)

(57) [Claims] 1. A means for slurrying solid organic matter contained in waste, a means for oxidatively decomposing and liquefying organic matter contained in the slurry at a high temperature and a high pressure in a wet oxidation vessel, and A system for mineralizing organic waste, comprising means for mineralizing with a catalyst. 2. The organic waste mineralization system according to claim 1, wherein the wet oxidation container includes an air addition device and a stirring means. 3. The organic waste mineralization system according to claim 1, wherein the catalyst mineralization means circulates the treatment liquid to the catalyst using a high-temperature and high-pressure circulation pump. 4. The system according to claim 1, further comprising a system for recovering and recycling exhaust heat generated in the wet oxidation process.
Or inorganic waste treatment system for organic waste 5. A means for converting a solid organic substance contained in waste into a slurry, a means for oxidatively decomposing and liquefying an organic substance contained in the slurry at a high temperature and a high pressure in a wet oxidation vessel, and A system for mineralizing organic waste, comprising: means for mineralizing with a catalyst; and plant cultivation means using a treatment liquid and exhaust gas generated from each of the means.