JP2001232153A - Gas duct equipment for waste asphalt lump regenerating equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas duct equipment for a waste asphalt lump regenerating equipment, which is provided with a deodorizing device unnecessary for the fuel expenses and the exchange of activated carbon, or the like. SOLUTION: The catalytic deodorizing device 30 is composed of a catalytic reaction tower 32, in which a ceramic 31 consisting of SiO2 and Al203 including Mg and having many acicular fine pores having 0.2-20 nm diameter is filled, and a water feed means 40 for feeding the adequate quantity of water to the ceramic 31. The adsorption, absorption and decomposition of malodorous materials in a waste gas are repeated by the ceramic 31. Because oxygen and water are used as the sources of the reaction, the deodorization process of the malodorous materials are continued without adding energy from the outside in particular.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for eliminating odorous substances in exhaust gas from waste asphalt lump recycling equipment.

[0002]

BACKGROUND OF THE INVENTION Paving roads with concrete or asphalt is well known, and asphalt pavement has become particularly widespread. If the pavement is used for a long time, the pavement will crack or wear down, and the pavement will need to be removed periodically or as necessary to remove the old pavement and apply new pavement. I do.

[0003] The pavement waste that has been landfilled is
Recycling has been attempted in response to a request for resource reuse, and in particular, asphalt pavement waste can be reused by crushing (also referred to as crushing) and then heat-treating.

FIG. 5 is a diagram showing the principle of a conventional waste asphalt lump recycling facility.
Is a rotary kiln type furnace 102 equipped with a burner 101
A flue 103 extending from the furnace 102, a dust collector 104 such as a dust collector or a bag filter, a combustion type deodorizing device 105, an exhaust blower 106, and a chimney 107 which are sequentially provided in the flue 103. . Combustion type deodorizer 10
Reference numeral 5 denotes an apparatus which has recently been adopted as one means of environmental measures. 108 is a filler supply unit,
Mix powder with flue gas as needed.

First, “waste asphalt” and “supplementary material” are charged into a furnace 102 and heated by a burner 101. By this process, the waste asphalt becomes “recycled mixture”.
When generated during this treatment, the exhaust gas 114 is sent to the dust removing means 104 through the flue 103 to remove dust and particles.
Combustion-type deodorizer 1 that further removes gas from which dust, particles, etc. have been removed
Send to 05. In the combustion type deodorizer 105, a malodorous substance (ammonia, methyl mercaptan, etc.) can be converted into an odorless substance by decomposing and oxidizing at a high temperature. The exhaust gas after the deodorization treatment is discharged from the chimney 107 to the atmosphere.

[0006]

The above-described combustion type deodorizer 105 consumes a large amount of fuel such as gas and heavy oil, and is not preferable in terms of energy saving. A large amount of carbon dioxide (CO ₂ ) is also generated with the combustion, which is not preferable in consideration of global warming.

As an alternative to the combustion type deodorizer, there is a deodorizer using activated carbon. Activated carbon has a large number of fine pores, and has a deodorizing effect because it traps malodorous substances. However, when the fine pores are full of malodorous substances, they must be replaced with new activated carbon and periodically (for example, 6 hours).
(Every 12 months, every 12 months), replacement costs are incurred.

As described above, in the conventional combustion type deodorizing apparatus, the fuel cost is increased and a large amount of carbon dioxide gas is released. In the activated carbon type deodorizing apparatus, replacement of activated carbon is indispensable. Has become. Therefore, an object of the present invention is to provide a flue equipment for a waste asphalt lump regenerating facility equipped with a deodorizing device that does not require a fuel cost and does not require replacement of activated carbon or the like.

[0009]

In order to achieve the above object, the flue equipment of the waste asphalt lump reclamation equipment according to claim 1 comprises:
The asphalt paving material peeling off from the road surface, the waste asphalt mass reproduction equipment for crushed heat treatment, the flue of the waste asphalt mass reproduction equipment, SiO ₂ containing Mg, A
A deodorizing device including a catalyst reaction tower made of l ₂ O ₃ and filled with ceramics having a myriad of needle-shaped micropores having a diameter of 0.2 nm to 20 nm, and a water supply means for supplying an appropriate amount of water to the ceramics is provided. It is characterized by having done.

[0010] The needle-shaped fine pores having a diameter of 0.2 nm to 20 nm of the ceramic are wetted with water. When an exhaust gas containing a malodorous substance is brought into contact therewith, the malodorous substance is decomposed and decomposed by an ion exchange action, a molecular classification effect and an oxidation / reduction action, and further converted and transformed into a new odorless product. This odorless substance leaves the needle-shaped micropores and is released to the atmosphere through the chimney. That is, the process of repeatedly adsorbing, absorbing, and decomposing malodorous substances with ceramics is repeated. Since oxygen and moisture serve as a source of the reaction (catalytic reaction), the odor eliminating process can be continued without applying extra energy from outside.

If the diameter of the acicular micropores is less than 0.2 nm, it is difficult to produce the micropores, and clogging tends to occur. On the other hand, if the diameter of the acicular micropores exceeds 20 nm, the required number of acicular micropores cannot be secured. That is, the adsorption area is reduced, and the intended detoxification treatment capacity is reduced. Therefore,
It is appropriate that the diameter of the acicular micropores is 0.2 nm to 20 nm.

[0012] The flue equipment of the waste asphalt lump regeneration equipment according to claim 2 is a waste asphalt lump regeneration equipment for crushing and heat-treating asphalt pavement material peeled off from the road surface,
In the flue of this waste asphalt lump recycling facility, S containing Mg
A deodorizing device comprising a catalytic reaction tower made of iO ₂ and Al ₂ O ₃ and filled with ceramics having a myriad of needle-like micropores having a diameter of 0.2 nm to 20 nm is interposed.

[0013] The needle-shaped micropores having a diameter of 0.2 nm to 20 nm of the ceramic are wetted with water contained in the exhaust gas. When an exhaust gas containing a malodorous substance is brought into contact therewith, the malodorous substance is decomposed and decomposed by an ion exchange action, a molecular classification effect and an oxidation / reduction action, and further converted and transformed into a new odorless product. This odorless substance leaves the needle-shaped micropores and is released to the atmosphere through the chimney. That is, the process of repeatedly adsorbing, absorbing, and decomposing malodorous substances with ceramics is repeated. Since oxygen and moisture serve as a source of the reaction (catalytic reaction), the odor eliminating process can be continued without applying extra energy from outside.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings should be viewed in the direction of reference numerals. FIG. 1 is a principle diagram of a waste asphalt lump regenerating facility according to the present invention.
0 is a rotary kiln type furnace 12 provided with a burner 11,
A flue 13 extending from the furnace 12, a dust-removing means 14 such as a dust collector or a bag filter, a catalytic deodorizing device 30, an exhaust blower 16, and a rotation of the exhaust blower 16. A rotation control unit 17 for controlling the
8 Reference numeral 19 denotes a filler supply unit which mixes powder (filler, dust, etc.) into the exhaust gas as required,
The dust reducing means 14 on the downstream side is protected. The rotation control unit 17 monitors the internal pressure of the furnace 12 and controls the rotation of the exhaust blower 16 so that the furnace internal pressure becomes constant (for example, atmospheric pressure).

Next, the operation of FIG. 1 will be described. First, “waste asphalt” and “supplementary material” are charged into a furnace 12 and heat-treated by a burner 11. Through this process, the waste asphalt becomes “recycled mixture”. The exhaust gas 24 generated during this treatment is sent to the dust-reducing means 14 through the flue 13. The dust removing means 14 removes dust and particles contained in the exhaust gas 24. The “recycled mixture” is recycled asphalt, and a material to be added to waste asphalt in manufacturing recycled asphalt is referred to as “supplementary material”.

The exhaust gas from which dirt, particles, etc. have been removed is further sent to a deodorizing device 30 and the exhaust gas after deodorizing treatment is passed to a chimney 1
8 to the atmosphere. The structure and operation of the deodorizing device 30 will be described later.

FIG. 2 is a sectional view of a catalytic deodorizing apparatus according to the present invention.
A catalytic reaction tower filled with ceramics 31 composed of O ₂ and Al ₂ O ₃ and having an innumerable needle-like micropores having a diameter of 0.2 nm to 20 nm (... Denotes a plurality, the same applies hereinafter). 3
2 and a water supply means 40 for supplying an appropriate amount of water to the ceramics 31.

More specifically, the catalytic reaction tower 32 is an airtight container having a gas inlet 33, a conical portion 34, a cylindrical portion 35, a conical portion 36, a gas outlet 37, a perforated plate 38, and a manhole 39. On the bottom, ceramics 31 ...
Fill. The catalyst reaction tower 32 may be an airtight container, and may be any of a vertically long cylinder, a horizontally long cylinder, a vertically long rectangular tube, a horizontally long rectangular tube, and a cubic container, and the shape is arbitrary.

The water supply means 40 includes a water supply pipe 41 and a water supply valve 4.
2, a water supply ring 43 attached to the conical portion 34 on the gas inlet 33 side, and a spray nozzle 4 attached to the water supply ring 43.
, And water (tap water or the like) sent through a water supply pipe 41 is sprinkled like a sprinkler through a water supply ring 43, a spray nozzle 44, and the like. However, the water supply is limited to such an extent that the ceramics 31 are wet. For this purpose, the temperature inside the catalytic reaction tower 32 is monitored, and when this temperature exceeds a certain value, or when the accumulated time of the processing work reaches a predetermined time, or when a certain time has elapsed simply by a timer, the water supply is performed. The valve 42 is opened and then closed.

In order to promote the catalytic action by the ceramics 31, the temperature must be kept at 100 ° C. or less. For this purpose, structural consideration is taken so that the temperature at the gas inlet 33 is 90 ° C. or lower. Specifically, the flue 1 in FIG.
The outside air (outside cold air) is blown into 3 to lower the exhaust gas temperature. The flue gas is not wrapped around the flue 13 to promote heat dissipation to lower the exhaust gas temperature. A water cooling jacket is attached to the flue 13 to forcibly cool the exhaust gas. This will lower the exhaust gas temperature.

FIG. 3 is a sectional view of a ceramic employed in the present invention. The ceramic 31 is made of Mg, SiO ₂ , A
An appropriate amount of l ₂ O ₃ and a binder are mixed and subjected to semi-molten crystallization at 250 to 300 ° C., whereby balls (balls), cylinders (tubes), and cones having a myriad of needle-like micropores having a diameter of 0.2 nm to 20 nm are obtained. These are elements finished in various geometric shapes such as (cone). Here, it is important that general fired ceramics become hard ceramics such as pottery and porcelain, which does not contribute to the present invention. The present invention is characterized in that the ceramics are made into relatively soft fired products, so-called soft ceramics.

FIG. 3 shows a cross section of the soft ceramic cylinder. In addition to a needle-like fine hole (not shown) having a diameter of 0.2 nm to 20 nm, a concave portion 46... It is expected that the interfacial reaction zone with the catalyst will be expanded, and the catalytic reaction efficiency will be dramatically improved.

FIG. 4 is a graph showing the deodorizing performance, in which the horizontal axis represents time, the left vertical axis represents the removal efficiency, and the right vertical axis represents the odor concentration based on the three-point comparative odor method. When the waste asphalt was heat-treated, an odorous substance having an odor concentration of about 5000 ppm was mixed in the exhaust gas, and an experiment was conducted to remove this with the ceramics 31 in the example and activated carbon in the comparative example.

The malodorous substances were ammonia, methyl mercaptan, hydrogen sulfide, acetaldehyde, propionaldehyde and the like. Waste asphalt consists of a number of substances such as asphalt, tar, additive chemicals, tire rubber sticking to the road surface, and from these, odorous substances are generated.

In the comparative example (activated carbon), the removal efficiency was reduced to 50% in less than 30 days, and was substantially zero in less than one year. This is because the activated carbon was saturated. Therefore, it is necessary to change the activated carbon every one to three months.

On the other hand, in the embodiment (catalytic ceramic),
Even after three years, the removal efficiency was maintained at 80%, and continuous use for about ten years was possible. The removal ability of the ceramics was restored by cleaning with a brush or brush.

The reason why the embodiment performed well is considered.
The ceramic of the present invention has a matrix (solid lattice) as a whole with Mg as a nucleus and attached with O (oxygen atom), Si (silicon), OH (hydroxyl group), Al (aluminum) and the like. It can be estimated that And
When water adheres to the needle-like micropores having a diameter of 0.2 nm to 20 nm, water molecules (H ₂ O) are converted into oxygen ions and hydroxyl ions by the catalytic action of elements (Mg, Si, Al, etc.) constituting the matrix. It decomposes and oxygen (O ₂ ) adheres to the acicular micropores in the form of oxygen ions. When the exhaust gas containing the odor reaches here, the malodorous substance which is the source of tar odor and rubber odor is oxidized or reduced, and as a result, H
It changes to ₂ O, CO ₂ and electrons (e). Part of H ₂ O is decomposed to exhibit an odor eliminating effect.

Here, it is important that the malodorous substance reacts with the needle-shaped micropores and then separates from the needle-shaped micropores together with the exhaust gas instead of the odorless substance. In other words, if activated carbon, the malodorous substance accumulates in the micropores, but the ceramic of the present invention does not accumulate the malodorous substance in the acicular micropores, and thus exhibits a deodorizing function for a long period of time. However,
If the ceramic is contaminated with soot, the function is reduced. This is the reason why the curve of the embodiment falls rightward in the graph.

The ceramic of the present invention does not exhibit its function in a dry state. Also, if it is dirty, it will not function.
On the other hand, if it is wet to the extent that it does not dry, and if the surface is cleaned to some extent, it exhibits a catalytic action of repeating adsorption → absorption → decomposition by oxidation / reduction → separation.

More specifically, the ion exchange phenomenon occurs actively due to the presence of water, and furthermore, in the absorption process, the odorous components are decomposed as a result of dissociating (or scoring) the molecular bonding hands of the odorous components in the absorption process. Would. From the viewpoint of the function as an oxidation catalyst, maintaining the ambient temperature of the target gas or odorous component in a temperature range higher than room temperature, that is, in a range of 50 ° C. to 90 ° C., in order for the catalyst to act efficiently. This is most desirable.

For this purpose, a water supply means 40 is provided permanently in FIG. However, if the water generating substance is put into the furnace 12 of FIG. 1 together with the waste asphalt 21, the exhaust gas discharged from the furnace 12 contains sufficient H ₂ O.
Becomes unnecessary. Therefore, whether or not the water supply means 40 is permanently installed may be determined according to the components of the generated gas.

Although the furnace 12 is a rotary kiln type furnace, another type of furnace may be used.

[0033]

According to the present invention, the following effects are exhibited by the above configuration. The flue equipment of the waste asphalt lump regeneration equipment according to claim 1 is a waste asphalt lump regeneration equipment for crushing and heating the asphalt pavement material peeled off from the road surface, wherein the flue of the waste asphalt lump regeneration equipment contains Mg. Si
A deodorizing apparatus comprising a catalytic reaction tower filled with ceramics made of O ₂ and Al ₂ O ₃ and having countless fine pores having a diameter of 0.2 nm to 20 nm and a water supply means for supplying an appropriate amount of water to the ceramics. It is characterized by being interposed, and repeatedly adsorbs, absorbs and decomposes odorous substances with ceramics. Oxygen and moisture are the sources of the reaction, so that the odor eliminating process can be continued without extra energy from outside.

[0034] The flue equipment of the waste asphalt lump regeneration equipment according to claim 2 is a waste asphalt lump regeneration equipment for crushing and heating the asphalt pavement material peeled off from the road surface.
In the flue of this waste asphalt lump recycling facility, S containing Mg
It is characterized in that a deodorizer consisting of a catalytic reaction tower made of iO ₂ and Al ₂ O ₃ and filled with ceramics having a myriad of needle-shaped micropores having a diameter of 0.2 nm to 20 nm is interposed, and is included in the exhaust gas. Water is used as reaction water, and ceramics repeatedly adsorb, absorb, and decompose odorous substances.
Oxygen and moisture are the sources of the reaction, so that the odor eliminating process can be continued without extra energy from outside.

[Brief description of the drawings]

FIG. 1 is a principle diagram of a waste asphalt lump recycling facility according to the present invention.

FIG. 2 is a sectional view of a catalytic deodorizing apparatus according to the present invention.

FIG. 3 is a sectional view of a ceramic employed in the present invention.

FIG. 4 is a graph showing deodorizing performance.

FIG. 5: Principle diagram of a conventional waste asphalt lump recycling facility

[Explanation of Signs] 10: Waste asphalt lump recycling equipment, 13: Flue, 24 ...
Exhaust gas, 30: deodorizer (catalytic deodorizer), 31: ceramics (catalytic ceramics), 32: catalytic reaction tower, 40: water supply means.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hisayoshi Suzuki 2-5-7 Tendai, Inage-ku, Chiba-shi, Chiba F-term (reference) 4Z048 AA22 AB01 AB03 BA01X BA03X BA06X BA41X BB01 BD06 CA07 CC38 CD05 EA04 4G069 AA02 AA08 AA10 BA03A BA03B BB04A BB04B BC10A BC10B CA02 CA04 CA07 CA08 CA10 CA17 DA06 EA02Y EC09X EC09Y GA09

Claims (2)

[Claims] 1. A waste asphalt lump recycling facility for crushing and heat-treating asphalt pavement material peeled off from a road surface, wherein the flue of the waste asphalt lump regeneration facility is made of SiO ₂ and Al ₂ O ₃ containing Mg, 0.2 nm to 20 n
Waste asphalt lump recycling characterized by interposing a deodorizing device consisting of a catalytic reaction tower filled with ceramics having an infinite number of needle-shaped fine holes of m diameter and a water supply means for supplying an appropriate amount of water to the ceramics. Equipment flue equipment. 2. A waste asphalt lump regeneration facility for crushing and heat-treating asphalt pavement material peeled off from a road surface, wherein the flue of the waste asphalt lump regeneration facility is made of SiO ₂ and Al ₂ O ₃ containing Mg, 0.2 nm to 20 n
A flue equipment for reclaiming waste asphalt lump, characterized by interposing a deodorizing device consisting of a catalytic reaction tower filled with ceramics having a myriad of needle-shaped fine holes of m diameter.