JP2012116919A - Treatment system of persistent organic waste liquid using nonequilibrium plasma combustion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a treatment system which reforms an organic waste liquid and produces combustible gas with high efficiency and in addition, which produces fullerene or a carbon-based high-function material in decomposition treatment of the persistent organic waste liquid using nonequilibrium plasma combustion.SOLUTION: The reaction of the persistent waste liquid with oxygen provided in an amount not enough to achieve the equivalent reaction of the persistent organic waste liquid is performed in a depressurized reaction tube by irradiating the reaction tube with microwave. Thus, more free radicals are generated than usual combustion, thereby increasing reactivity. Also, the reactivity is increased by injecting (spraying) the organic waste liquid, thereby producing the combustible gas with high efficiency. In addition, the fullerene or the carbon-based high-function material is produced by changing the oxygen ratio, increasing the microwave output, or utilizing a catalyst.

Description

  The present invention decomposes a hardly decomposable organic waste liquid by non-equilibrium plasma combustion, generates a combustible gas and fullerene or a carbon-based high-functional material as a product after decomposition, and uses the combustible gas for power generation by a power generator. The present invention relates to a treatment system for persistent organic waste liquid that can be used.

  Electrical insulation oil used for transformers, etc. becomes waste oil by replacement by regular inspection. The waste oil needs to be decomposed into a substance having a low environmental load from the viewpoint of environmental conservation in recent years.

  As a method for treating waste oil, a method using high-frequency induction thermal plasma is conventionally known as an example (see Patent Document 1).

JP-A-8-131757

  In the processing method described in Patent Document 1, the argon gas is replaced with a reactive gas suitable for decomposition of waste oil such as oxygen, water vapor, and hydrogen, and then heated to 1000 to 2000 ° C. by being exposed to a high-temperature plasma flame. By supplying waste oil to the tank, the waste oil is instantly evaporated and decomposed to promote reaction with oxygen. The decomposed material is discarded to the outside through the exhaust port.

  According to this treatment method, the amount of oxygen or the like for treating the waste oil is the minimum amount necessary for the decomposition treatment of the waste oil, so that the amount of exhaust gas can be suppressed.

  However, in recent years, there has been an increasing social demand for effective use of waste after it has been properly treated from the viewpoint of effective use of resources in addition to environmental conservation. In the treatment method described in Patent Document 1, the exhaust gas is harmless and excellent in terms of environmental conservation, but on the other hand, the product produced by decomposing waste oil is directly used effectively. Is more preferable from the viewpoint of effective use of resources.

  Therefore, in view of the above problems, the present invention provides a treatment system for a hardly decomposable organic waste liquid that can directly use a combustible gas generated by decomposing a hardly decomposable organic waste liquid for power generation. Objective.

  The invention described in claim 1 includes a processing device that decomposes a hardly-decomposable organic waste liquid in a non-equilibrium plasma combustion field, and a power generation device that generates power using the combustible gas decomposed and generated in the processing device. It is characterized by comprising.

  According to a second aspect of the present invention, in the first aspect of the invention, the processing apparatus irradiates microwaves into a reduced-pressure reaction tube, and inputs oxygen used for decomposition and a hardly-decomposable organic waste liquid to be decomposed. A non-equilibrium plasma combustion field is generated, and the hardly decomposable organic waste liquid is decomposed.

  According to a third aspect of the present invention, in the invention according to the first or second aspect, the amount of oxygen supplied as a reaction gas in the processing apparatus is less than an equivalent reaction of a hardly decomposable organic waste liquid. By making the supply amount, most of the decomposed product is made into a combustible gas.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects of the present invention, the processing apparatus decomposes the hardly decomposable organic waste liquid in a non-equilibrium plasma combustion field, thereby performing normal combustion. The flammable organic waste liquid treatment system according to any one of claims 1 to 3, wherein the combustible gas is produced in a larger amount than in the first embodiment.

The invention according to claim 5 generates a larger amount of free radicals such as OH radicals than the conventional combustion by using a non-equilibrium plasma combustion field in the invention according to any one of claims 1 to 4. In addition, it is characterized by decomposing a hardly decomposable organic waste liquid in a highly reactive reaction field.

  The invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein the reaction tube is attached to a probe for introducing a hardly decomposable organic waste liquid and a tip of the probe. The nozzle is configured to be inserted through a nozzle that sprays the hardly decomposable waste liquid onto the reaction tube.

  The invention according to claim 7 is the invention according to any one of claims 1 to 6, wherein the treatment device decomposes the hardly-decomposable organic waste liquid, thereby adding carbon-based high A functional material or fullerene is produced.

  According to an eighth aspect of the present invention, in the invention according to any one of the first to seventh aspects, the power generation device includes a gas engine or a gas turbine.

  According to the invention described in claim 1, since it is possible to generate power directly by the power generation device using the combustible gas generated by decomposing the hardly decomposable organic waste liquid, it is possible to effectively use resources, Contributes to reducing environmental impact.

  According to the invention described in claim 2, compared to a conventional decomposition treatment apparatus using thermal equilibrium plasma, it is possible to generate a reaction field higher than normal combustion with very little energy, and greatly reduce running costs. it can.

 According to the invention described in claim 3, by limiting the amount of oxygen as a reaction gas to a supply amount that does not satisfy the equivalent reaction, most of the product after decomposing the hardly-decomposable organic waste liquid by non-equilibrium plasma combustion. Can be used as combustible gas, so that the amount of power generated by the power generator can be improved.

  According to the invention described in claim 4, in the non-equilibrium plasma combustion of the present invention, the reaction part is irradiated with microwaves, so that a stable reaction can be realized, and there is no problem that the reaction stops unexpectedly, It becomes possible to continuously and efficiently decompose the hardly decomposable organic waste liquid to be decomposed.

According to the invention described in claim 5, since non-equilibrium plasma combustion is performed by irradiating microwaves into a decompressed system, combustion is performed, and thus more reactive radicals such as OH radicals are generated than normal combustion. A high reaction field can be generated.

  According to the sixth aspect of the present invention, it is possible to accelerate the decomposition treatment of the hardly decomposable waste liquid by spraying the hardly decomposable waste liquid introduced through the probe in a mist form using a nozzle in the reaction tube. .

  According to the seventh aspect of the invention, a useful carbon-based high-functional material or fullerene can be produced from the waste liquid.

  According to invention of Claim 8, it becomes possible to generate electric power easily using the produced | generated combustible gas by utilizing a known gas engine or gas turbine.

It is a whole block diagram which shows the processing system of the hardly decomposable organic waste liquid which concerns on this invention. It is a principal part expansion longitudinal cross-sectional view which expands and shows the reaction part in the processing apparatus which comprises the processing system of the said hardly decomposable organic waste liquid. It is a spectroscopic analysis result which compared the increase amount of the free radical which is the characteristic of the nonequilibrium plasma combustion used by this invention with normal combustion. The composition and generation amount of the combustible gas generated by the decomposition using the nonequilibrium plasma combustion of the present invention are shown.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 shows a processing system A for hardly decomposable organic waste liquid using non-equilibrium plasma combustion according to the present invention.

  A processing system A (hereinafter simply referred to as a processing system) for a hardly decomposable organic waste liquid includes a microwave generator 1, a microwave waveguide 2, an input part 3 for a hardly decomposable organic waste liquid, a reaction gas supply unit 4, and a reaction tube. 5, a processing device B for the hardly decomposable organic waste liquid, and a product reuse unit 7 that uses the product after the hardly decomposable organic waste liquid is decomposed.

  The microwave waveguide 2 includes an isolator 8 that absorbs the reflected microwave and a micro wave to prevent the microwave oscillated from the microwave generator 1 from being reflected and entering the microwave generator 1. A power monitor 9 for checking the intensity of the wave and a stub tuner 10 for resonating the microwave and focusing on the plasma generation position are provided. Reference numeral 11 denotes a pressure gauge for measuring the atmospheric pressure in the reaction tube 5 whose pressure is adjusted by the vacuum pump 6.

  The product recycling unit 7 includes a heat exchanger 12 that cools a product generated by decomposing the hardly-decomposable organic waste liquid, and a power generator 13 that generates power using the gas sucked and discharged by the vacuum pump 6. It is configured.

  Reference numeral 14 denotes an observation window for viewing the reaction state in the reaction part X (see FIG. 2). In the reaction part X, the reaction tube 5 is installed perpendicularly to the microwave waveguide 2, and the upper part is The lower part is connected to the heat exchanger 12 and connected to the charging part 3 and the reaction gas supply part 4.

  In the reaction tube 5, the lower end of a narrow tube (hereinafter referred to as a probe) 15 whose upper end is connected to the input unit 3 extends to the upper part of the non-equilibrium plasma combustion field, and is connected to the tip (lower end) of the probe 15. Is attached with a nozzle (hereinafter referred to as a spray nozzle) 16 for spraying the hardly-decomposable waste liquid supplied from the input unit 3 via the probe 15 in the form of a mist.

  The reaction tube 5 is formed of, for example, a transparent quartz tube, and allows microwaves oscillated from the microwave generator 1 shown in FIG. 1 and passed through the plasma waveguide 2 to pass through the reaction tube 5.

  Next, the processing method of the hardly decomposable organic waste liquid by the processing system A according to the present invention will be described. The processing system A shown in FIG. 1 can decompose a hardly decomposable organic waste liquid such as insulating oil.

  As the insulating oil, for example, there is an electrical insulating oil for a pole transformer, and the insulating oil is a pure hydrocarbon which is composed of carbon and hydrogen and does not contain other elements.

  In decomposing the insulating oil, first, oxygen is supplied as a reaction gas from the reaction gas supply unit 4 shown in FIG. 1, and the supply amount of oxygen at this time is less than the equivalent reaction described later. Set. The supplied oxygen passes through the reaction tube 5 downward as shown in FIG. 1, and is supplied to the reaction section X shown in FIG.

  Next, the inside of the reaction tube 5 is depressurized and fixed to a predetermined pressure (for example, 4 kPa) using the vacuum pump 6 and the pressure gauge 11, and the microwave generated by the microwave generator 1 in this state is output to a predetermined output ( 700W etc.).

  The microwave output from the microwave generator 1 propagates to the power monitor 9 through the microwave waveguide 2 and the isolator 8, and incident power is detected by the power monitor 9. At this time, the isolator 8 protects the microwave generator 1 by absorbing the reflected microwave. The power of the reflected microwave is detected by the power monitor 9.

  The microwave that has passed through the waveguide 2 is resonated by the stub tuner 10 and enters the reaction part X so that the maximum amount of microwave is consumed in the reaction tube shown in FIG.

  The microwave incident on the reaction part X passes through the reaction tube 5 made of a transparent quartz tube or the like satisfactorily. At this time, oxygen is supplied as a reaction gas from the reaction gas supply unit 4 shown in FIG. 1 into the reaction tube 5, and this oxygen is ionized by incident microwaves to be turned into plasma.

  The plasma generated at this time is generated by glow discharge since the inside of the reaction tube 5 is depressurized to a constant pressure (for example, 4 kPa). Glow discharge is a more stable discharge in a wider range than corona discharge, and can be generated with lower energy than arc discharge.

When glow discharge plasma is generated in the reaction part X, the insulating oil to be processed is introduced from the introduction part 3 in a liquid state. The insulating oil is supplied from the probe 15 shown in FIG.
The input amount of the insulating oil is set so that the amount of oxygen supplied as the reaction gas does not satisfy the equivalent reaction.

  When insulating oil is simply introduced as droplets, the reaction area is small and the reaction efficiency is poor. Therefore, the spray is sprayed in the form of a mist from the spray nozzle 16 attached to the lower end (tip) shown in FIG. By making it into a mist, the reaction area increases and the reaction efficiency can be improved.

  At this time, the insulating oil reacts rapidly with oxygen in the form of plasma, resulting in non-equilibrium plasma combustion. Non-equilibrium plasma combustion is a combustion method having a thermal non-equilibrium plasma reaction, while normal combustion proceeds by a chemical reaction with thermal equilibrium.

An example of a non-equilibrium plasma combustion thermal non-equilibrium chemical reaction is an increase in free radicals, particularly OH radicals. As shown in the spectroscopic analysis results in FIG. 3, many radicals are detected in non-equilibrium plasma combustion compared to normal combustion, and more than 10 times more are detected especially for OH radicals.

OH radicals are extremely reactive radicals and are very effective in decomposing refractory waste.

In addition, since the amount of oxygen as a reaction gas is less than the equivalent reaction, combustible gas is generated even in normal combustion, but in the case of non-equilibrium plasma combustion, as shown in FIG. Combustible gas can be generated. Moreover, synthesis of by-product carbon compounds such as tar can be suppressed by converting the hardly decomposable organic waste liquid into more combustible gas.

  The product gas is composed of hydrogen, carbon monoxide, carbon dioxide, and other low-molecular hydrocarbons. Among them, the proportion of combustible gas of hydrogen, carbon monoxide, and low-molecular hydrocarbons accounts for 80% of the total.

  The generated combustible gas is cooled by the heat exchanger 12 by the suction force of the vacuum pump 6 and then discharged to the power generation device 13. As the power generation device 13, a gas engine or a gas turbine is used, and the generator can be driven by the gas engine using the combustible gas discharged from the vacuum pump 6, or the gas turbine can be rotated to generate power. . That is, it becomes possible to generate renewable energy from the waste liquid.

  In addition, oxygen is separately supplied to the outer peripheral portion of the probe 15 in the reaction tube, and soot (carbon) adheres in the reaction tube 5 by forming a relatively high oxygen concentration around the probe 15. It is possible to prevent the microwave from interfering with the permeation tube 5.

  On the other hand, in addition to the generation of the combustible gas, the present invention can generate a carbon-based high-functional material and fullerene.

  The production of the carbon-based high-functional material can be promoted by increasing the output of the microwave or mixing it with a waste liquid (insulating oil) that decomposes a predetermined catalyst. And the produced | generated carbon-type highly functional material and fullerene can be collect | recovered from the reaction tube 5 lower part with undecomposed insulating oil.

  By using the above method, the injected insulating oil is decomposed in a non-equilibrium plasma combustion field, so that a combustible gas for power generation and a carbon-based highly functional material or fullerene can be generated from a hardly decomposable organic waste liquid such as insulating oil. it can. Carbon-based high-performance materials are used in diamonds, automobiles and sporting goods, etc. Carbon nanomaterials that are expected to be used as semiconductors in the future, DLC used for surface processing of cutting tools and automotive parts (Diamond-like carbon), pharmaceuticals, cosmetics, fullerenes being considered for use in semiconductor materials, and the like are considered. In addition, fullerene can be used as a lubricant or a solar cell material.

  As described above, the processing system for persistent organic waste liquid according to the present invention decomposes persistent organic waste liquid such as insulating oil with high efficiency and reforms it into combustible gas, fullerene or carbon-based high-performance material. The generated combustible gas can be used for power generation using a gas engine or a gas turbine.

  In addition, when the waste liquid is decomposed by irradiation with microwaves, the reaction does not stop even if the supply of the waste liquid becomes unstable, and stable decomposition is possible.

  Further, by spraying the waste liquid in a mist form from the spray nozzle, the reaction area of the waste oil is increased, and the waste liquid can be efficiently decomposed.

  It can be used for decomposition treatment of persistent organic waste liquid using non-equilibrium plasma combustion.

DESCRIPTION OF SYMBOLS 1 Microwave generator 2 Microwave waveguide 3 Input part 4 Reaction gas supply part 5 Reaction tube 6 Vacuum pump 7 Product reuse unit 8 Isolator 9 Power monitor 10 Stub tuner 11 Pressure gauge 12 Heat exchanger 13 Power generator 14 Observation Window 15 tubule (probe)
16 Spray nozzle A Refractory organic waste liquid treatment system B Refractory organic waste liquid treatment equipment X Reactor

Claims (8)

A difficulty characterized in that it comprises a processing device that decomposes a hardly decomposable organic waste liquid in a non-equilibrium plasma combustion field, and a power generation device that generates power using the combustible gas decomposed and generated in the processing device. Decomposable organic waste liquid treatment system. The processing apparatus generates a non-equilibrium plasma combustion field by irradiating microwaves into a depressurized reaction tube and introducing oxygen used for decomposition and a hardly decomposable organic waste liquid to be decomposed. The system for treating a hardly decomposable organic waste liquid according to claim 1, wherein the system is configured to decompose. The treatment apparatus is configured such that most of the decomposed product becomes a combustible gas by setting the amount of oxygen supplied as the reaction gas to a supply amount that does not satisfy the equivalent reaction of the hardly decomposable organic waste liquid. The processing system of the hardly decomposable organic waste liquid in any one of Claim 1 or Claim 2 characterized by these. The said processing apparatus produces | generates many combustible gas compared with combustion by decomposing | disassembling a hardly decomposable organic waste liquid in a non-equilibrium plasma combustion field. The processing system of the hard-to-decompose organic waste liquid described in 1. The said processing apparatus produces | generates many free radicals compared with combustion by using a non-equilibrium plasma combustion field, and decomposes | disassembles a hardly decomposable organic waste liquid in a highly reactive reaction field. The processing system of the hardly decomposable organic waste liquid in any one of Claims 4 thru | or 4. The reaction tube is configured by inserting a probe for introducing a hardly decomposable organic waste liquid and a nozzle attached to the tip of the probe and spraying the introduced hardly decomposable waste liquid onto the reaction tube. The processing system of the hardly decomposable organic waste liquid in any one of Claims 1 thru | or 5. 7. The processing apparatus according to claim 1, wherein the processing apparatus is configured to generate a carbon-based high-functional material or fullerene in addition to the combustible gas by decomposing the hardly decomposable organic waste liquid. The processing system of the hardly decomposable organic waste liquid in any one. The system for treating a hardly decomposable organic waste liquid according to any one of claims 1 to 7, wherein the power generation device includes a gas engine or a gas turbine.

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