JP2001050518A - Waste dry distillation apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep and secure clean and safe waste gas with a dry distillation gas processing for waste containing organic matter. SOLUTION: There are provided a heating furnace 1 for heating waste, an air cleaning tube 7 for exhausting dry distillation gas from the heating furnace 1, a gas cleaning section 9 communicated with the air cleaning tube 7 and including an oxygen catalyst 13, a fuel tube 15 and communicated with an upper stream of the gas cleaning section 9 and a fuel control valve 16 for controlling the flow rate thereof, and a catalysis temperature detection section 17, whereby the amount of fuel supply from the fuel tube 15 is controlled such that the temperature of the oxidative catalyst 13 is substantially predetermined temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for purifying a carbonized gas in an apparatus for heating and carbonizing waste containing combustible organic matter to reduce the amount of carbonized waste.

[0002]

2. Description of the Related Art Methods for reducing the amount of waste containing combustible organic matter, such as garbage discharged from ordinary households and school facilities and residues discharged from food processing plants, include incineration and biofermentation. In addition to the treatment, a number of methods have been proposed in the prior art, in which the carbonized material is reduced by heating to dry distillation, and the generated carbide is used as a soil modifier. In this heating and carbonization method, a purification treatment of generated carbonization gas is required. As a treatment method, a method of introducing into a flame combustion furnace and subjecting to high-temperature incineration or a method of purifying by oxidation using an oxidation catalyst is used. It has been known.

[0003]

In the above-mentioned conventional method, the method of introducing a carbonization gas into a flame combustion furnace and burning it is as follows.
Although it can be a relatively simple and compact device,
Since the composition and amount of the generated carbonization gas are not constant, it is difficult to maintain a complete reaction, and there is a problem that unburned components are easily discharged. On the other hand, in the method using the oxidation catalyst, as shown in FIG. 4, the gas is carried out from the carbonization furnace 21 by the scavenging fan 22 to the oxidation catalyst 26 whose temperature is maintained by the flame burner 25 provided in the gas processing chamber 24. The burnt gas is conducted through the scavenging pipe 23, a part of the combustible component is oxidized by the flame near the flame burner 25, and the remaining component is completely purified by the oxidation catalyst 26. For this reason, it is possible to discharge clean exhaust gas that has been completely processed from the exhaust port 27. However, in this configuration, when the combustible material concentration of the carbonization gas discharged from the carbonization furnace 21 fluctuates greatly, the flame burner 25
In the case where the stable combustion is impaired, or when a large amount of combustibles is contained, the amount of heat generated in the vicinity of the flame burner 25 becomes excessive, which may cause a problem such as an abnormal rise in the temperature of the oxidation catalyst 26. In order to stabilize combustion in the flame burner 25, excessive air mixing must be avoided. However, if the amount of combustibles is excessive, air shortage will occur significantly, and an oxidation catalyst 26 is provided downstream. However, the oxidation reaction could not be performed, and unreacted substances such as odor and carbon monoxide were discharged. Further, the amount of combustion of the flame burner 25 is adjusted so that the oxidation catalyst 26 is usually controlled at around 200 to 500 ° C., but when the waste contains salt or a halogen compound, the vicinity of the flame burner 25 is reduced. In this case, the temperature becomes sufficiently high, and the generation of harmful components such as dioxins is suppressed. However, the temperature is a temperature at which the generation of dioxins can occur in the downstream oxidation catalyst 26, which includes the possibility of re-generation.

[0004] The present invention solves such a conventional disadvantage,
To provide a waste carbonization treatment device capable of maintaining stable complete combustion even with fluctuations in the amount of combustibles in the carbonization gas generated from the carbonization furnace and maintaining and maintaining clean exhaust gas characteristics that do not generate harmful emissions. It is intended for.

[0005]

According to a first aspect of the present invention, there is provided a heating furnace for heating waste, heating means for the heating furnace, and heating means for heating the waste. Scavenging means for sucking and removing the carbonized gas from the furnace, communicating with the upstream or downstream of the scavenging means, gas processing means provided with an oxidation catalyst therein, and fuel disposed and communicated on the upstream side of the gas processing means. And / or a means for supplying air and a means for detecting the temperature of the oxidation catalyst, wherein a flow control means for controlling at least a fuel supply amount in accordance with a detection signal from the temperature detecting means is interlocked. It is a material distillation apparatus.

A second invention (corresponding to claim 2) is a first invention.
In the waste distillation apparatus according to the present invention, the fuel supply amount is controlled by the flow control means so that the temperature of the oxidation catalyst is maintained at 800 ° C. or higher.

A third aspect of the present invention (corresponding to claim 3) is:
The waste carbonization treatment apparatus according to the first or second aspect of the present invention includes a waste conveying means which operates in one direction while passing through the heating furnace having at least an inlet opening, and is suction-removed by the scavenging means. The heating furnace is provided with an air supply means for supplying a large amount of oxygen-deficient gas to the heating furnace, and a supply means for supplying air and fuel upstream of the exhaust gas treatment means. Is what you do.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

In the practice of the present invention, in addition to the heating means for the heating furnace, the temperature control means in the heating furnace, the scavenging means, the air and fuel supply means and control means, the catalyst temperature detecting means, The configuration of the transport unit and its driving means are required. As the heating means, in addition to heating by an electric heater, a combustion-type heating device using a liquid or gaseous fuel can be used. In addition, as a means for measuring the temperature of the inside of the dry distillation furnace or the oxidation catalyst, any number of thermocouples and thermistors are installed at any positions and used, and in conjunction with this, means for controlling the supply amounts of fuel and air include:
This can be handled by controlling the voltage and frequency of the electric valve and the blower fan. A fan can be generally used for scavenging and suctioning gas, but a pump can be used depending on the need for pressure and suction force. As a means for transporting waste, a fluidized bed in which a heat-resistant metal belt is rotated can be used, or a rotating rod (roller) continuously arranged can be used. As a driving means, a motor drive is generally used. These are all means conventionally used, and other known means are also possible. In the present specification, the technical description thereof will be omitted.

(Embodiment 1) First, the configuration of a waste dry distillation apparatus according to Embodiment 1 of the present invention will be described with reference to FIG.

FIG. 1 is a schematic structural view of a waste dry distillation apparatus according to Embodiment 1 of the present invention. In FIG. 1, reference numeral 1 denotes a tunnel-shaped heating furnace in which an electric heater 2 is embedded in a wall surface. Reference numeral 3 denotes a furnace temperature detecting unit for detecting the temperature in the heating furnace 1, which is connected to a furnace temperature controller 4, and controls a voltage applied to the electric heater 2 based on a difference between the detected temperature and a set temperature. Numeral 5 denotes a belt for transporting wastes formed of a belt-shaped metal net installed in the heating furnace 1, and 6 denotes a roller section for driving the belt 5. Reference numeral 7 denotes a scavenging pipe which is provided with an open end inside the heating furnace 1 and suctions and exhausts the carbonization gas. An exhaust fan 11 is connected downstream of the scavenging pipe via a gas purification unit 9 and an exhaust pipe 10. An exhaust top 12 is provided downstream of the exhaust fan 11. An oxidation catalyst 13 in which an oxidizing component of an organic combustible is carried on a honeycomb-shaped ceramic is built in the gas purification unit 9, and a space inside the gas purification unit 9 downstream of the oxidation catalyst 13 is cleaned. A heat exchanging part 14 configured to penetrate the trachea 7 is arranged. Reference numeral 15 denotes a fuel pipe for supplying a fuel gas (here, LP gas is used).
The flow rate is controlled by the fuel control valve 16. Reference numeral 17 denotes a catalyst temperature detecting section which is arranged in contact with the oxidation catalyst 13 and is connected to a combustion controller 18 for transmitting a signal, and for generating a signal for operating the fuel control valve 16 therefrom.

Next, the operation and operation of this embodiment will be described. The heating furnace 1 whose temperature is detected by the furnace temperature detection unit 3 and the applied power is controlled by the furnace temperature controller 4 is set to an internal temperature of about 500 ° C., where a large amount of organic substances such as kitchen garbage and fish and vegetable residues are contained. Including waste. The waste rides on the transport belt 5 driven by the roller unit 6 and moves so as to penetrate the heating furnace 1, and as the temperature rises, moisture and pyrolysis products are generated. These generated gases (carbonized gas) receive suction force by the exhaust fan 11 and are sucked and exhausted from the scavenging pipe 7. The dry distillation gas flowing through the scavenging pipe 7 is supplied to the gas purification unit 9 where the gas purification unit 9
The temperature of the oxidation catalyst 13 inside is raised in advance so as to receive the fuel gas supplied from the fuel pipe 15 and oxidize the fuel gas, and when the carbonization gas is supplied, the oxidation purification is immediately performed here. . The exhaust gas after the reaction is exhaust gas 1
After passing through 0, the air is conveyed from the exhaust fan 11 to the exhaust top 12 and discharged to the outside.

Here, high-temperature exhaust gas is generated downstream of the oxidation catalyst 13, but since the scavenging pipe 7 penetrates and heat is recovered in the heat exchange section 14, the temperature is lowered to the exhaust fan 11. The exhaust gas flows, and the carbonization gas is supplied to the upstream of the oxidation catalyst 13 in a state where the temperature is high and the reactivity is increased, so that a complete reaction can be easily performed even if components which are difficult to oxidize are mixed. Becomes Further, the catalyst temperature detecting unit 1
7, the temperature state of the oxidation catalyst 13 is always detected, and when the temperature of the oxidation catalyst 13 is lower than the predetermined temperature, the fuel control valve 16 is opened to increase the supply amount of the fuel gas, and conversely, When the temperature becomes higher than the set upper limit temperature due to the heat of reaction, control is performed via the combustion controller 18 in the direction in which the fuel control valve 16 is throttled, and the temperature of the oxidation catalyst 13 is constantly controlled to an optimal temperature state. .

The air (oxygen) necessary for the oxidation reaction of the fuel and the carbonization gas in the oxidation catalyst 13 is supplied with a sufficient amount of air together with the carbonization gas since the inlet and outlet sides of the transport zone 5 of the heating furnace 1 are open. Is also supplied through the scavenging pipe 7, and need not be separately supplied. In addition, the amount of carbonized gas generated, especially the amount of combustible gas contained therein, may fluctuate greatly depending on the type and amount of waste and the state (change in water content, compression ratio, etc.) of the waste. 1
In the catalytic oxidation reaction using No. 3, as long as the required temperature is maintained, the reaction can be sufficiently completed even in a lean state, and the generation of unburned substances and intermediate products can be prevented.

FIG. 2 shows an example of a control chart at the time of actual operation. Although the amount of combustible gas generated from waste (solid line) greatly fluctuates with time, the operation is performed within a necessary and sufficient temperature range by controlling the amount of fuel supply stepwise according to the temperature of the oxidation catalyst 13. Can be. Therefore, there is no need to detect and identify the amount and type of the dry distillation gas, which is a mixture of various components, and it is possible to maintain and secure a clean exhaust gas only by rough control of the fuel gas corresponding to the temperature of the oxidation catalyst 13. .

By the way, various kinds of materials are expected to be mixed in the waste. Particularly, when chlorides (including salt and the like) and halogen compounds (including plastic pieces and the like) are mixed, 300 to 700 are mixed. Harmful dioxins can be produced in a temperature range of about ° C. Here, by controlling the temperature of the oxidation catalyst 13 to 800 ° C. or higher, the state in which dioxins are thermally decomposed can be prevented, and discharge of dioxins to the outside can be prevented. Downstream of the oxidation catalyst 13, the temperature is rapidly lowered in the heat exchange section 14, so that it is also possible to avoid regenerating dioxins from the decomposition gas. Since the exhaust gas is in a clean and completely oxidized state, a water-cooled heat exchanger or the like may be provided downstream of the gas purifier 9 if necessary.
It is also possible to cool to 0 ° C. or less.

The residue after the carbonization gas has been discharged is in a carbonized state, and its volume has been reduced to a fraction of its initial value. In addition, it can be used as a soil modifier or fertilizer, or as an adsorbent for sewage or sludge, or as a solid fuel or a reducing agent, and can be used to recycle previously difficult-to-treat waste as useful raw material. Will be.

(Embodiment 2) Next, Embodiment 2 of the present invention will be described. The basic structure and operation of the waste carbonization treatment device of the present embodiment are the same as those of the waste carbonization treatment device of the first embodiment. Are different in air supply means. Therefore, the present embodiment will be described focusing on this difference.

FIG. 3 is a schematic diagram showing the configuration of a waste carbonization apparatus according to the present embodiment. As shown in FIG. 3, near the inlet and outlet of the heating furnace 1, an air supply pipe 8 for supplying nitrogen gas is provided, and nitrogen gas having a flow rate exceeding the amount of dry distillation gas sucked and exhausted from the scavenging pipe 7 is supplied. Supplied. On the other hand, an air supply pipe 19 is connected upstream of the gas purification section 9 along with the fuel supply pipe 15.

In this configuration, since the waste is heated in a state where the heating furnace 1 is filled with nitrogen gas, there is no danger that the combustible gas generated by the heating reacts there and ignites significantly. it can. Further, the oxidation polymerization reaction and the like in the heating furnace 1 can be suppressed, and the generation of dioxins can be avoided. Since the dry distillation gas generated therefrom does not contain air (oxygen) necessary for the oxidation reaction, a sufficient amount of air is strongly mixed with the air from the air supply pipe 19 upstream of the gas purification section 9. As a result, the carbonized gas becomes a combustible mixture, and the oxidation reaction can be performed by the oxidation catalyst 13.
The amount of air to be supplied here must be equal to or greater than the equivalent amount of the combustible gas that can be generated from the heating furnace 1 assuming the maximum amount of combustible gas. Since the reaction can be performed even in a lean fuel state), a constant amount of excess may always be supplied, and there is no need to finely control according to the combustion state.

The gas supplied from the air supply pipe 8 into the heating furnace 1 is for the purpose of reducing the oxygen concentration in the atmosphere, and a pure gas such as nitrogen is necessarily supplied if this purpose is achieved. There is no necessity. For example, it is possible to circulate and use the soot having a low oxygen concentration such as the exhaust gas flowing through the exhaust pipe 10, and it is possible to realize simplicity and economy without impairing the present effect.

Although the present invention has been described above with reference to an example in which the present invention is applied to a dry distillation apparatus using electric heating, it goes without saying that the present invention is not limited to this. That is, the effects of the present invention are exhibited in the following cases.

As the heating means, gas fuel supplied by piping such as city gas or propane gas, or combustion heat using liquid fuel such as kerosene can be applied.
If combustion heat is used, air supply means for combustion such as a blower fan is added as necessary. In particular, when liquid fuel is used, liquid fuel is supplied upstream of the heating means (that is, the combustion section). Is added.

As a configuration of the oxidation catalyst 13 provided in the gas purifying section 9, a ceramic honeycomb is used as a base material here, but the material and shape of the catalyst base material are not limited. Body, metal honeycomb, metal nonwoven fabric, braided ceramic fiber, etc. can be used, and the shape is not limited to a flat plate, but can be set arbitrarily according to the workability and use of the material, such as a curved shape, a tubular shape, or a corrugated shape I can do it. This is the same as the active ingredient, and platinum, palladium, and noble metals such as white metals such as rhodium are generally used. It is often possible to select an active ingredient according to the type of fuel and use conditions.

[0025]

As is evident from the above description, the present invention provides a method of carbonizing and reducing carbonized waste by subjecting waste containing combustible organic matter to dry distillation, thereby completely oxidizing and purifying generated dry distillation gas to obtain a clean product. It is possible to provide a waste treatment apparatus capable of securing exhaust gas and obtaining a carbonized product that can be developed as a reusable resource.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a configuration of a waste carbonization treatment apparatus according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of operating characteristics of the above-mentioned device.

FIG. 3 is a schematic configuration diagram of a waste dry distillation apparatus according to Embodiment 2 of the present invention.

FIG. 4 is a schematic diagram of a configuration of a conventional waste disposal apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heating furnace 2 Electric heater 3 Furnace temperature detection part 4 Furnace temperature controller 5 Transport zone 6 Roller part 7 Scavenging pipe 8 Supply pipe 9 Gas purification part 10 Exhaust pipe 11 Exhaust fan 12 Exhaust top 13 Oxidation catalyst 14 Heat exchange part 15 Fuel pipe 16 Fuel control valve 17 Catalyst temperature detecting section 18 Combustion controller 19 Air supply pipe

 ──────────────────────────────────────────────────の Continuing on the front page (72) Keizo Nakajima Inventor 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. Terms (reference) 3K061 AA18 AA23 AB02 AC01 AC06 AC17 AC19 BA08 BA10 CA01 CA12 DA17 DA18 DA19 DB03 FA03 FA10 FA21

Claims (4)

[Claims] 1. A heating furnace for charging and heating flammable organic waste, heating means for raising the temperature of the heating furnace to a predetermined temperature, and scavenging means for sucking and removing carbonized gas generated in the heating furnace. A gas treatment means communicating upstream or downstream of the scavenging means and having an oxidation catalyst therein; a fuel and / or air supply means arranged upstream of the gas treatment means and communicating therewith; A waste carbonization treatment apparatus, comprising: a temperature detecting means; and a flow rate control means for controlling at least a supply amount of the fuel supply means in accordance with a detection signal of the temperature detecting means. 2. The fuel supply unit is controlled by the flow control unit such that the temperature of the oxidation catalyst disposed inside the gas treatment unit is maintained at 800 ° C. or higher. Waste distillation equipment. 3. A heating device having a heating means having at least an inlet opening and a means for transporting input waste, which operates in one direction, and which is larger than the amount of dry distillation gas sucked and removed by the scavenging means. 3. The carbonization of waste as claimed in claim 1, further comprising an air supply means for supplying the oxygen-deficient gas into the heating furnace, and an air and fuel supply means upstream of the exhaust gas treatment means. Processing equipment. 4. A flow path configured so that the dry distillation gas sucked and removed from the heating furnace passes through a high-temperature exhaust flow path of the gas processing means and undergoes heat exchange. The waste carbonization treatment device according to any one of 2 and 3.