JP2001300527A - Method and device decomposing difficult-to-decomposed organic mater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decompose a difficult-to-decompose organic matter contained in water, sludge and slurry at normal temperature and pressure, with a small quantity of energy and without using special chemicals or forming a by-product. SOLUTION: An object 2 to be treated is irradiated with an ultrasonic wave of the frequency to vibrate and extraction-treat the solid phase of the object 2 and an ultrasonic wave of the frequency to decompose the liquid phase of the object 2 from ultrasonic wave generators 7a and 7b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for decomposing hardly decomposable organic substances, and includes water, sludge, and slurry such as leachate, sewage, and human waste at a final disposal site for general waste and industrial waste. The present invention relates to a technique for decomposing hard-to-decompose organic substances.

[0002]

2. Description of the Related Art Heretofore, as a method for decomposing hardly decomposable organic substances, for example, dioxins in a solid substance have been
Melt processing method to melt under high temperature conditions of more than
A supercritical treatment method in which treatment is performed under high temperature and high pressure conditions of 370 ° C. or more and 22 MPa or more has been confirmed. Alternatively, an alkali-catalyzed decomposition method in which a hydrogen donor, an alkali, and a solvent are added to an object to be treated and then heated at about 350 ° C. in a nitrogen atmosphere has been confirmed.

[0003]

However, in the above-described structure, the energy consumption for maintaining the conditions of high temperature and high pressure is large, the running cost is high, and the dioxin in the solid phase is formed by using a solvent. When transferring wastes into the liquid phase, by-products such as harmful substances and ecotoxic substances other than dioxins may be generated, and are included in water such as landfill leachate, sewage, human waste, sludge, and slurry. It is difficult to apply the above-mentioned method when decomposing the hardly decomposable organic matter.

The present invention has been made to solve the above-mentioned problems, and uses a small amount of energy at room temperature and normal pressure to convert a hardly decomposable organic substance such as dioxins and pesticides contained in water, sludge, and slurry. An object of the present invention is to provide a method and an apparatus for decomposing hardly decomposable organic substances, which can be decomposed without using chemicals or by-products.

[0005]

According to a first aspect of the present invention, there is provided a method for decomposing a hardly decomposable organic substance, comprising the steps of: Ultrasonic waves having a frequency that exerts a vibration extracting action on the solid phase of the above and an ultrasonic wave having a frequency that has a decomposing action on the liquid phase in the object to be treated are irradiated.

[0006] With the above configuration, the ultrasonic transmitter is 1k.
Transmits an ultrasonic wave having a specific frequency from the range of Hz to 1 MHz. In the object to be treated, a hardly decomposable organic substance such as dioxins is adsorbed on the surface of a solid phase substance such as soil or is taken in. When this hardly decomposable organic substance is irradiated with ultrasonic waves having a specific strong frequency, it undergoes the vibration energy of the ultrasonic waves and undergoes a vibration extraction action to move from a solid phase to a liquid phase. The frequency at which this vibration extraction effect is exerted differs depending on the physical properties of the object to be processed, and is obtained in advance as an empirical rule.

On the other hand, when the liquid phase is irradiated with ultrasonic waves of a specific frequency, cavitation bubble cavities are generated. When this cavity collapses, a radical state is generated at the same time as a unique state of several hundred atmospheres and several thousand degrees is obtained by adiabatic compression. Among the hardly decomposable organic substances that have shifted to the liquid phase, substances that are relatively hydrophilic and contain a large amount of unsaturated bonds are decomposed by reacting with generated radicals. Organic compounds having a relatively low vapor pressure (for example, trichloroethylene) are taken into the cavity and decomposed at high temperature and high pressure. The frequency of this decomposition depends on the physical properties of the object to be treated,
Obtain in advance as a rule of thumb.

According to a second aspect of the present invention, there is provided a method for decomposing a hardly decomposable organic substance, wherein an ultrasonic wave having a frequency which exerts a vibration extracting action and an ultrasonic wave having a frequency which has a decomposing action are provided at predetermined time intervals. Are alternately irradiated.

According to this structure, the vibration-extracting action and the decomposition action of the hard-to-decompose organic substance are alternately repeated, whereby the hard-to-decompose organic substance attached to the solid phase is effectively decomposed, and the frequency at which the action of the hard-to-decompose organic substance exerts the decomposition action is increased. Higher decomposition efficiency can be obtained as compared with the case where only sound waves are irradiated.

[0010] According to a third aspect of the present invention, there is provided an apparatus for decomposing a hardly decomposable organic substance, comprising: a reaction tank for storing an object to be treated; a stirrer for stirring the object to be treated in the reaction tank; It has a plurality of ultrasonic transmitters installed separately, and each ultrasonic transmitter decomposes into ultrasonic waves of a frequency that exerts vibration extraction action on the solid phase in the processing object and liquid phase in the processing object It transmits an ultrasonic wave having a frequency that acts.

[0011] With the above-described structure, while the object to be stored in the reaction tank is stirred by the stirrer, the ultrasonic waves having the frequency of exerting the vibration extracting action and the ultrasonic waves having the frequency of effecting the decomposition action are applied from each ultrasonic transmitter to the object to be processed. Transmits ultrasonic waves. For transmission of ultrasonic waves, ultrasonic waves of two frequencies may be simultaneously transmitted from separate ultrasonic transmitters, or ultrasonic waves of two frequencies may be transmitted alternately at predetermined time intervals.

According to a fourth aspect of the present invention, there is provided an apparatus for decomposing a hardly decomposable organic substance, comprising a water channel having a shallow water depth through which an object flows, and a plurality of ultrasonic transmitters arranged at predetermined intervals along the flow direction of the water channel. Ultrasonic transmitter that has a body and transmits ultrasonic waves at a frequency that exerts vibration extraction on the solid phase in the processing object, and transmits ultrasonic waves at a frequency that decomposes the liquid phase in the processing object And ultrasonic transmitters are alternately installed.

According to the above-described structure, the object to be processed is alternately irradiated with the ultrasonic waves having the frequency of exerting the vibration extracting function and the ultrasonic waves of the frequency having the decomposing function, which are transmitted from the respective ultrasonic wave transmitting bodies, as they flow through the water channel. Is done.

According to a fifth aspect of the present invention, there is provided an apparatus for decomposing a hardly decomposable organic substance, comprising: an ultrasonic transmitter for transmitting an ultrasonic wave having a frequency which exerts a vibration extracting action on a solid phase in an object to be processed; Equipped with an ultrasonic transmitter that transmits ultrasonic waves of a frequency that has a decomposing effect on the liquid phase inside, a plurality of reaction tanks that separately install each ultrasonic transmitter, and a circulation system that communicates each reaction tank It is a thing.

According to the above-described structure, the object to be treated alternately emits ultrasonic waves having a frequency that exerts a vibration extracting action and ultrasonic waves having a frequency that exerts a decomposing action while circulating through a plurality of reaction vessels through a circulation system. Is irradiated.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, objects to be treated 2 stored in a reaction tank 1 are landfill leachate, sewage, human waste, etc. at a final disposal site for general waste and industrial waste, and the water, sludge, and slurry are dioxins. It contains hard-to-decompose organic substances such as and pesticides.

The reaction tank 1 has a supply system 4 having a pump 3 for supplying the processing object 2 and a discharge system 5 for discharging the processing object.
And a stirrer 6 for stirring the object 2 is provided inside the tank. A plurality of ultrasonic transmitters 7a and 7b are installed at predetermined intervals at the bottom of the tank, and the ultrasonic transmitters (horns) 7a and 7b are connected to a first ultrasonic oscillator 9a through a first waveguide 8a. Ultrasonic transmitter 7a connected to
And an ultrasonic transmitter 7b connected to a second ultrasonic oscillator 9b through a second waveguide 8b are alternately arranged at a predetermined interval. The first ultrasonic oscillator 9a oscillates an ultrasonic vibration having a frequency that exerts a vibration extracting action on the solid phase of the processing object 2, and the second ultrasonic oscillator 9b decomposes into a liquid phase of the processing object 2. It oscillates ultrasonic vibration at a frequency that exerts an effect. The ultrasonic transmitter 7 may use a vibrator made of ceramic or the like that oscillates upon receiving a voltage.

The ultrasonic waves transmitted from the ultrasonic transmitters 7a and 7b are selected from the range of 1 kHz to 1 MHz.
The frequency at which the vibration extraction action and the decomposition action occur depend on the physical properties of the object to be treated, for example, the type and composition of the hardly decomposable organic matter, the properties of sludge and soil, or the shape of the reaction tank 1, so that it is an empirical rule. Is determined in advance.

The operation of the above configuration will be described below. The processing object 2 is supplied from the supply system 4 to the reaction tank 1 and oscillated by the first ultrasonic oscillator 9a and the second ultrasonic oscillator 9b while the processing object 2 stored in the reaction tank 1 is stirred by the stirrer 6. Ultrasonic waves are emitted to the processing target 2 from each of the ultrasonic transmitters 7a and 7b.

The hardly decomposable organic substances such as dioxins in the object to be treated are adsorbed on the surface of a solid substance such as soil or are taken into the inside. First ultrasonic transmitter 7a
When ultrasonic waves having a strong frequency that exerts a vibration extracting action are applied from the substrate, the hardly decomposable organic substance is transferred from a solid phase to a liquid phase by the vibration extracting action by receiving the vibration energy of the ultrasonic waves.

On the other hand, when the second ultrasonic wave transmitter 7b irradiates an ultrasonic wave having a high frequency which has a decomposing effect, cavitation bubble cavities are generated in the liquid phase. When this cavity collapses, the adiabatic compression produces a unique state of several hundred atmospheres and thousands of degrees,
Radicals are generated.

For this reason, among the hardly decomposable organic substances that have moved into the liquid phase, a relatively hydrophilic substance containing a large amount of unsaturated bonds is decomposed by reacting with a radical, and is relatively hydrophobic and has a low vapor pressure. The compound is taken into the cavity and decomposed at high temperature and pressure.

The ultrasonic wave of the vibration extraction function and the ultrasonic wave of the decomposition function emitted from the first ultrasonic transmitter 7a and the second ultrasonic transmitter 7b may be irradiated alternately at predetermined time intervals. In the present embodiment, ultrasonic waves of two frequencies are transmitted from separate ultrasonic transmitters 7a and 7b, respectively, and ultrasonic waves of two frequencies are transmitted from the same ultrasonic transmitters 7a and 7b every predetermined time. You may send them alternately.

FIG. 2 shows another embodiment of the present invention. Members that perform the same operations as in the previous embodiment are given the same reference numerals, and description thereof is omitted.
In FIG. 2, a water channel 11 through which the processing object 2 flows has a shallow structure, and a first waveguide 8 a is provided at the bottom of the water channel 11.
A plurality of ultrasonic transmitters 7a connected to the first ultrasonic oscillator 9a through the second ultrasonic generator 7b and a plurality of ultrasonic transmitters 7b connected to the second ultrasonic oscillator 9b through the second waveguide 8b are arranged along the flow direction. They are installed at predetermined intervals.

With the above-described configuration, as the processing target 2 flows through the water channel 11, the ultrasonic waves having the frequency that exerts the vibration extracting action transmitted from the respective ultrasonic transmitters 7 a and the ultrasonic transmitters 7 b transmit. Ultrasonic waves of a frequency that exerts a decomposition action are alternately irradiated, and extraction and decomposition of the hardly decomposable organic matter occur alternately. Other functions and effects are the same as those of the previous embodiment.

FIG. 3 shows another embodiment of the present invention. Members that perform the same operations as in the previous embodiment are given the same reference numerals, and description thereof is omitted.
In FIG. 3, an ultrasonic transmitter 7 a for transmitting an ultrasonic wave having a frequency that exerts a vibration extracting action on the solid phase of the processing object 2 is provided in a first reaction tank 21, and a second reaction tank 22 is provided in the second reaction tank 22. ,
An ultrasonic transmitter 7b for transmitting an ultrasonic wave having a frequency that decomposes the liquid phase of the processing object 2 is provided. The first reaction tank 21 and the second reaction tank 22 communicate with each other via a circulation system 24 having a circulation pump 23.

With the above configuration, the processing object 2 flowing from the supply system 4 to the circulation system 24 is circulated between the first reaction tank 21 and the second reaction tank 22 by driving the circulation pump 23. The object 2 to be treated in the first reaction tank 21 is irradiated with an ultrasonic wave having a frequency that exerts a vibration extracting effect transmitted from the first ultrasonic transmitter 7a, and the hardly decomposable organic substance shifts from the solid phase to the liquid phase. The object 2 to be treated in the second reaction tank 22
Is irradiated with ultrasonic waves transmitted from the second ultrasonic transmitter 7b and having a frequency that causes a decomposition action, whereby the hardly decomposable organic substances in the liquid phase are decomposed. For this reason, in the system, the extraction action and the decomposition action of the hardly decomposable organic matter are alternately and repeatedly performed in a cycle, and the processing target 2 with respect to the first ultrasonic transmitter 7a and the second ultrasonic transmitter 7a. Contact frequency increases,
The irradiation efficiency of ultrasonic waves of each frequency is improved, and the decomposition efficiency is improved. Other functions and effects are the same as those of the previous embodiment.

[0028]

As described above, according to the present invention, an intense ultrasonic wave having a specific frequency is irradiated, and the hardly decomposable organic substance is transferred from the solid phase to the liquid phase by the vibration extraction action. Irradiates ultrasonic waves with a specific strong frequency to decompose hard-to-decompose organic substances in a unique reaction field of several hundred atmospheres, thousands of degrees generated when the cavity collapses, or by reaction with radicals . In addition, high decomposition efficiency can be obtained by alternately irradiating ultrasonic waves of two frequencies and alternately repeating the vibration extraction action and the decomposition action of the hardly decomposable organic substance. Therefore, the hardly decomposable organic substance can be decomposed at normal temperature and normal pressure with little energy without using special chemicals or by-products.

[Brief description of the drawings]

FIG. 1 is a schematic view of a decomposition apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic view of a decomposition apparatus according to another embodiment of the present invention.

FIG. 3 is a schematic view of a decomposition apparatus according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reaction tank 2 Processing object 3 Pump 4 Supply system 5 Discharge system 6 Stirrer 7a, 7b Ultrasonic transmitter 8a 1st waveguide 8b 2nd waveguide 9a 1st ultrasonic oscillator 9b 2nd ultrasonic oscillator 11 Water channel 21 first reaction tank 22 second reaction tank 23 circulation pump 24 circulation system

Claims (5)

[Claims] 1. An ultrasonic wave having a frequency exerting a vibration extracting action on a solid phase in a processing object from an ultrasonic transmitter to a processing object, and a ultrasonic wave having a frequency exerting a decomposition action on a liquid phase in the processing object. And a method for decomposing a hardly decomposable organic substance. 2. The method according to claim 1, wherein an ultrasonic wave having a frequency that exerts a vibration extracting action and an ultrasonic wave having a frequency that causes a decomposition action are alternately irradiated from the ultrasonic transmitting body at predetermined time intervals. A method for decomposing hardly decomposable organic substances. 3. It has a reaction tank for storing an object to be processed, a stirrer for stirring the object to be processed in the reaction tank, and a plurality of ultrasonic transmitters installed at predetermined intervals in the tank. The ultrasonic transmitter emits an ultrasonic wave having a frequency that exerts a vibration extraction action on a solid phase in a processing object and an ultrasonic wave having a frequency that has a decomposition action on a liquid phase in the processing object. A device for decomposing hard-to-decompose organic substances. 4. A shallow water channel through which an object flows,
It has a plurality of ultrasonic transmitters arranged at predetermined intervals along the flow direction of the water channel, and an ultrasonic transmitter that transmits ultrasonic waves having a frequency that exerts a vibration extraction action on a solid phase in the processing object,
An apparatus for decomposing hard-to-decompose organic substances, comprising: an ultrasonic transmitter that transmits ultrasonic waves having a frequency that decomposes a liquid phase in a processing object. 5. An ultrasonic transmitter for transmitting an ultrasonic wave having a frequency that exerts a vibration extracting action on a solid phase in a processing object, and transmitting an ultrasonic wave having a frequency that decomposes a liquid phase in the processing object. An apparatus for decomposing hard-to-decompose organic substances, comprising: an ultrasonic transmitter, a plurality of reaction vessels in which the ultrasonic transmitters are separately installed, and a circulation system communicating the reaction vessels.