JPS6223123B2 - - Google Patents
Info
- Publication number
- JPS6223123B2 JPS6223123B2 JP54073272A JP7327279A JPS6223123B2 JP S6223123 B2 JPS6223123 B2 JP S6223123B2 JP 54073272 A JP54073272 A JP 54073272A JP 7327279 A JP7327279 A JP 7327279A JP S6223123 B2 JPS6223123 B2 JP S6223123B2
- Authority
- JP
- Japan
- Prior art keywords
- waste
- asphalt
- particles
- crushed
- dryer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000002699 waste material Substances 0.000 claims description 76
- 239000010426 asphalt Substances 0.000 claims description 61
- 239000002245 particle Substances 0.000 claims description 57
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 17
- 230000002542 deteriorative effect Effects 0.000 claims description 3
- 238000000034 method Methods 0.000 description 18
- 238000010438 heat treatment Methods 0.000 description 7
- 238000004064 recycling Methods 0.000 description 7
- 239000000203 mixture Substances 0.000 description 6
- 230000006866 deterioration Effects 0.000 description 4
- 239000002131 composite material Substances 0.000 description 3
- 230000035515 penetration Effects 0.000 description 3
- 239000004902 Softening Agent Substances 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 239000003921 oil Substances 0.000 description 2
- 238000009412 basement excavation Methods 0.000 description 1
- 239000011362 coarse particle Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000013021 overheating Methods 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 239000010734 process oil Substances 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 239000002352 surface water Substances 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Landscapes
- Road Paving Machines (AREA)
- Working-Up Tar And Pitch (AREA)
Description
【発明の詳細な説明】
本発明は、既設アスフアルト舗装の打ち換え、
補修、更には既設アスフアルト舗装下に埋設され
る設備の工事に伴つて生ずるアスフアルト舗装廃
材の再生方法に関するものである。[Detailed description of the invention] The present invention provides replacement of existing asphalt pavement,
The present invention relates to a method for recycling asphalt pavement waste material generated during repair and construction of equipment buried under existing asphalt pavement.
アスフアルト舗装廃材は、埋立地などに投棄し
ているが、年々発生する廃材量が増加しており、
その投棄地の確保が困難となつてきた。一方、省
資源化時代を向えてこのアスフアルト舗装廃材の
再生が注目されてきた。 Asphalt pavement waste is disposed of in landfills, etc., but the amount of waste generated is increasing every year.
Securing a dumping site has become difficult. On the other hand, as we move towards an era of resource conservation, the recycling of asphalt pavement waste has attracted attention.
これらのアスフアルト舗装廃材は、適当な配合
設計の基にアスフアルトと各種骨材とが混合され
ているものであるから、これを加熱してそのアス
フアルトを溶融すればアスフアルト合材として充
分に使用し得ることが明らかである。 These asphalt pavement waste materials are a mixture of asphalt and various aggregates based on an appropriate mixing design, so if this is heated and the asphalt is melted, it can be used satisfactorily as an asphalt mixture. That is clear.
アスフアルト舗装廃材を加熱溶融する方法とし
ては、加熱蒸気を使用する方法、熱風を使用する
方法などがあるが、一般的には公知のアスフアル
トプラントにおける骨材加熱装置であるドライヤ
ーを利用して熱風を使用することが考えられてい
る。そして、これまでの実験報告によれば、例え
ば特開昭54―17927号公報に示すように、その使
用する熱風の温度が約400〜600℃であれば、廃材
中に含まれるアスフアルトの劣化を防止しながら
廃材を加熱再生できるとされており、従来の廃材
再生ドライヤーは熱風温度を約400〜600℃の範囲
内で制御するように構成されている。しかしなが
ら、600℃以下の熱風によつて廃材を加熱すると
きは熱効率が極めて低く、多額の設備費を投入し
た割には期待される様な再生能力に到達し得なか
つた。 Methods for heating and melting asphalt pavement waste include methods that use heated steam and methods that use hot air, but generally speaking, hot air is heated using a dryer, which is an aggregate heating device in a known asphalt plant. It is considered to be used. According to previous experimental reports, for example, as shown in JP-A-54-17927, if the temperature of the hot air used is approximately 400 to 600 degrees Celsius, the asphalt contained in the waste material will deteriorate. It is said that it is possible to heat and regenerate waste materials while preventing this, and conventional waste material recycling dryers are configured to control the hot air temperature within a range of approximately 400 to 600 degrees Celsius. However, when heating waste materials with hot air at temperatures below 600°C, the thermal efficiency is extremely low, and the expected regeneration capacity could not be achieved despite the large amount of equipment costs invested.
本発明は、これらの欠点を改善することを目的
とするものであつて、ドライヤーに投入する廃材
破砕粒子に水分を充分に湿潤させておくことによ
り、これを加熱する熱風を650〜900℃にまで上昇
させても廃材中のアスフアルトの劣化を防ぐこと
ができると共に、この650〜900℃の熱風により熱
効率よく廃材を加熱してこれを再生することので
きるアスフアルト舗装廃材の再生方法を提供する
ものである。 The purpose of the present invention is to improve these drawbacks, and by sufficiently moistening the crushed waste particles to be fed into the dryer, the hot air used to heat the particles can be heated to a temperature of 650 to 900°C. To provide a method for recycling asphalt pavement waste material, which can prevent the deterioration of asphalt in the waste material even if the temperature rises to a temperature of It is.
即ち、本発明はアスフアルト舗装廃材を破砕し
水分をその廃材に対して約３〜７重量％湿潤させ
た後、この廃材破砕粒子をドライヤーに投入する
と共に、ドライヤー内におけるその廃材破砕粒子
の移動方向に沿つてドライヤー内に約650〜900℃
の熱風を供給することにより、廃材破砕粒子に湿
潤させた水分によつて廃材中に含まれるアスフア
ルトの劣化を防止しながら廃材を加熱再生するこ
とを特徴としたアスフアルト舗装廃材の再生方法
を要旨とするものである。 That is, in the present invention, after crushing asphalt pavement waste material and moistening the waste material with water by about 3 to 7% by weight, the crushed waste particles are put into a dryer, and the direction of movement of the crushed waste particles in the dryer is Approximately 650-900℃ in the dryer along
This article describes a method for recycling asphalt pavement waste material, which is characterized by heating and recycling the waste material while preventing the deterioration of the asphalt contained in the waste material by supplying hot air to the crushed waste material particles with moisture. It is something to do.
アスフアルト舗装廃材を破砕する手段として
は、既設アスフアルト舗装体を堀り起す際に大型
クラツシヤーを導入してその堀り起しと破砕とを
同時に行う方法、堀り起したアスフアルト舗装廃
材をそのまま破砕機にかけて破砕する方法、更に
は堀り起したアスフアルト舗装廃材を高温水蒸
気、温水、熱風などの加熱手段を単独或は組合せ
て使用し廃材中に含まれるアスフアルトを軟化さ
せた後、これをそのまま撹拌し、或は別の撹拌機
に投入して破砕する方法などがある。本発明で使
用するアスフアルト舗装廃材は前述何れの方法で
破砕してもよいが、その破砕した廃材破砕粒子に
水分を湿潤させることからすれば、高温水蒸気、
温水を利用した加熱手段を単独或は組合せて使用
することにより廃材中に含まれるアスフアルトを
軟化させ、その雰囲気化で廃材を撹拌破砕する方
法を採用するのが能率的である。 Methods for crushing asphalt pavement waste include a method in which a large crusher is introduced when excavating the existing asphalt pavement and the excavation and crushing are performed simultaneously; In addition, asphalt pavement waste material that has been excavated is softened by heating means such as high-temperature steam, hot water, and hot air, either alone or in combination, to soften the asphalt contained in the waste material, and then this is stirred as it is. , or crushing by putting it into another stirrer. The asphalt pavement waste used in the present invention may be crushed by any of the methods described above, but from the perspective of moistening the crushed waste particles with water, high-temperature steam,
It is efficient to adopt a method in which the asphalt contained in the waste material is softened by using heating means using hot water alone or in combination, and the waste material is stirred and crushed in the atmosphere created by the softening method.
本発明において、破砕したアスフアルト舗装廃
材粒子に水分を湿潤させる方法としては、前述の
ようにアスフアルト舗装廃材を破砕する時に併せ
て水分を湿潤させることもできるが、他の方法と
しては破砕したアスフアルト舗装廃材粒子に対し
て散水する方法、蒸気を吹付ける方法、破砕した
アスフアルト舗装廃材粒子を水、温水中に浸漬す
る方法などがある。この湿潤させる水分の量は、
約３〜７重量％程度が好ましく、湿潤させる水分
の量が少なすぎると熱風による蒸発が早く廃材を
過熱しアスフアルトを劣化させる。また、過度に
水分を湿潤させると熱風の熱量損失が多くなる
上、再生されるアスフアルト合材中に水分が残存
する恐れが生ずる。温水と蒸気とを利用して破砕
したアスフアルト舗装廃材粒子の含水率をサンプ
ル測定して見たところ、廃材破砕粒子の粒径０〜
5m／ｍのもので5.5〜7.5重量％、粒径５〜13m／
ｍのもので2.9〜4.4重量％、粒径13〜30m／ｍの
もので1.6〜2.49重量％であつた。従つて、これ
ら廃材破砕粒子を適宜配合した場合の含水率は約
３〜７重量％となり、本発明で使用するのに適し
たアスフアルト舗装廃材の破砕粒子となる。 In the present invention, as a method for moistening the crushed asphalt pavement waste particles with moisture, it is possible to moisten the crushed asphalt pavement waste particles at the same time as crushing the asphalt pavement waste as described above, but other methods include There are methods of sprinkling water on the waste material particles, methods of spraying steam, and methods of immersing crushed asphalt pavement waste material particles in water or hot water. The amount of this moistening water is
Approximately 3 to 7% by weight is preferable; if the amount of moisture to be moistened is too small, evaporation by hot air will be rapid, overheating the waste material and deteriorating the asphalt. In addition, excessive moisture content increases the loss of heat from the hot air, and there is a risk that moisture may remain in the recycled asphalt mixture. When we measured the moisture content of asphalt pavement waste particles crushed using hot water and steam, we found that the particle size of the crushed waste particles ranged from 0 to 0.
5m/m 5.5-7.5% by weight, particle size 5-13m/
The amount was 2.9 to 4.4% by weight for those with a particle size of 13 to 30 m/m, and 1.6 to 2.49% by weight for those with a particle size of 13 to 30 m/m. Therefore, when these crushed waste particles are appropriately blended, the water content is approximately 3 to 7% by weight, resulting in crushed particles of asphalt pavement waste suitable for use in the present invention.
このようにして水分を多量に湿潤させたアスフ
アルト舗装廃材の破砕粒子は、比較的比熱の大き
い水によつて被覆となるので熱容量が増大し、高
温の熱風を作用させてもその湿潤している水分に
よつて高温化を妨げることができるのである。そ
の状態をドライヤー内における供給された熱風と
廃材破砕粒子との温度の変化、および廃材破砕粒
子の含水率の変化について観察すれば、第１図に
示す通りである。即ち、期間におけるドライヤ
ーの入口附近において、供給された含水率4.2％
の廃材破砕粒子は直ちに840℃の熱風により加熱
されて順次温度を上昇させ約70℃にまで昇温す
る。そして、期間におけるドライヤーの中間に
位置する主作業部分を移行する間において、廃材
破砕粒子の表面は湿潤させた水分により被覆され
ているので、この表面水膜の存在により熱風の熱
量はそのほとんどを水分の蒸発に消費されてしま
い、高温の熱風を使用しているにも拘らず廃材破
砕粒子が高温になるのを妨げ、廃材破砕粒子の温
度は約70℃とほぼ一定に保つことができ、廃材破
砕粒子中に存在するアスフアルトの劣化を防止し
ながら、これを軟化させることができるのであ
る。次いで、ドライヤーの排出口に近い期間に
至つて、廃材破砕粒子に湿潤させてあつた水分は
蒸発し除去されることとなるので、廃材破砕粒子
の温度は再び上昇することとなり約180℃に達し
た。しかしながらドライヤーの投入口側から供給
される熱風の熱量もこの排出口側にあつては減少
しており、廃材破砕粒子をアスフアルトの劣化温
度である300℃以上に加熱することはないので、
廃材破砕粒子中に含有されるアスフアルトを劣化
させる心配のないことが理解できる。 The crushed particles of asphalt pavement waste that have been moistened with a large amount of water in this way are coated with water that has a relatively high specific heat, so their heat capacity increases, and even when high-temperature hot air is applied, the particles remain moist. Moisture can prevent high temperatures. If the state is observed in terms of changes in temperature between the hot air supplied in the dryer and the crushed waste particles, and changes in the moisture content of the crushed waste particles, the results are as shown in FIG. In other words, the supplied moisture content near the dryer inlet during the period was 4.2%.
The crushed waste particles are immediately heated by hot air at 840°C and the temperature is gradually increased to about 70°C. During the transfer of the main working part located in the middle of the dryer, the surface of the crushed waste particles is covered with moistened moisture, so the presence of this surface water film absorbs most of the heat from the hot air. The water is consumed by evaporation, and even though high-temperature hot air is used, the temperature of the crushed waste particles is prevented from reaching a high temperature, and the temperature of the crushed waste particles can be kept almost constant at approximately 70℃. It is possible to soften the asphalt present in the crushed waste particles while preventing them from deteriorating. Next, near the outlet of the dryer, the moisture that has moistened the crushed waste particles evaporates and is removed, so the temperature of the crushed waste particles rises again, reaching approximately 180°C. did. However, the amount of heat of the hot air supplied from the dryer's input port side is also reduced when it comes to this discharge port side, and the crushed waste particles will not be heated above 300℃, which is the deterioration temperature of asphalt.
It can be seen that there is no risk of deterioration of the asphalt contained in the crushed waste particles.
次に、本発明の実施例について説明する。 Next, examples of the present invention will be described.
既設アスフアルト舗装体を堀り起して生じたア
スフアルト舗装廃材を温水槽に投入し、これに高
温水蒸気を噴射することによりアスフアルト舗装
廃材を軟化しアスフアルトで薄くコーテイングさ
れた砕石粒に分離する。この分離されたアスフア
ルト廃材破砕粒子を粒度別にふるい分けする。 Asphalt pavement waste material produced by excavating an existing asphalt pavement body is put into a hot water tank, and high-temperature steam is injected into it to soften the asphalt pavement waste material and separate it into crushed stone particles thinly coated with asphalt. The separated crushed asphalt waste particles are sieved according to particle size.
この粒度別に選別したアスフアルト廃材破砕粒
子を粒径５〜13m／ｍのもの70重量％と粒度０〜
5m／ｍのもの30重量％とを配合して密粒度、ま
た粒径13〜30m／ｍのもの20重量％と粒径５〜
13m／ｍのもの80重量％とを配合して粗粒度の骨
材構成として取り出した。この密粒度に配合され
た廃材破砕粒子の合成含水率は約4.5％、粗粒度
に配合された廃材破砕粒子の合成含水率は約３％
であつた。 Of the crushed asphalt waste particles sorted by particle size, 70% by weight of particles with a particle size of 5 to 13 m/m and 70% by weight of particles with a particle size of 0 to 13 m/m.
5m/m and 30% by weight of particles with a particle size of 13~30m/m and 20% of particles with a particle size of 5~30m/m and a particle size of 5~
80% by weight of 13m/m was mixed and taken out as a coarse aggregate composition. The synthetic moisture content of the crushed waste particles blended with this dense particle size is approximately 4.5%, and the synthetic moisture content of the crushed waste wood particles blended with the coarse particle size is approximately 3%.
It was hot.
これらの配合された廃材破砕粒子をそれぞれド
ライヤーに投入して810〜840℃の熱風を供給し加
熱したところ再生されたアスフアルト合材を得
た。 These blended crushed waste particles were each put into a dryer and heated by supplying hot air at 810 to 840°C to obtain a recycled asphalt mixture.
これら廃材破砕粒子のドライヤー投入前、およ
びドライヤー排出後におけるその廃材破砕粒子に
附着するアスフアルトを抽出して、それぞれのア
スフアルトにおける針入度、軟化点、伸度を測定
したところ、第２〜４図に示すように何れの場合
もドライヤー投入前とドライヤー排出後における
変化は極めて少なく、加熱によるアスフアルトの
性状変化は認められなかつた。 The asphalt adhering to these crushed waste particles before being put into the dryer and after being discharged from the dryer was extracted, and the penetration, softening point, and elongation of each asphalt were measured. Figures 2 to 4 show the results. As shown in Figure 2, in all cases, there were very few changes between before being put into the dryer and after being discharged from the dryer, and no change in the properties of the asphalt due to heating was observed.
またこのようにして再生されたアスフアルト合
材に対し石油分留油（プロセスオイル、丸善石油
製品）を軟化剤として５重量％、10重量％添加し
た時のアスフアルトを抽出し、そのアスフアルト
の針入度、軟化点、伸度を測定したところ、第２
〜４図に示すように通常のアスフアルトの性状に
近い値が得られた。従つて、軟化剤を本発明の方
法により再生されたアスフアルト合材に５〜10重
量％添加する時には通常に生産されるアスフアル
ト合材と同様に使用し得る良質な再生アスフアル
ト合材となる。 Furthermore, the asphalt obtained by adding 5% and 10% by weight of petroleum fractionated oil (process oil, Maruzen Oil Products) as a softening agent to the recycled asphalt mixture was extracted, and the asphalt was penetrated. When we measured the degree of elasticity, softening point, and elongation, we found that the second
As shown in Figure 4, values close to the properties of ordinary asphalt were obtained. Therefore, when a softening agent is added in an amount of 5 to 10% by weight to asphalt composite material recycled by the method of the present invention, a high quality recycled asphalt composite material that can be used in the same manner as normally produced asphalt composite material is obtained.
叙上のように、本発明による時は、アスフアル
ト舗装廃材粒子に多量の水分を湿潤させてあるの
で、高温の熱風を作用させてもアスフアルトを劣
化させることなく、熱効率よく加熱することがで
きるのであつて、従来の廃材再生方法に比較して
廃材画生能力を増大させることのできる実益を有
する。 As mentioned above, according to the present invention, asphalt pavement waste particles are moistened with a large amount of water, so even if high-temperature hot air is applied, the asphalt does not deteriorate and can be heated efficiently. In addition, it has the practical benefit of increasing the waste material drawing ability compared to conventional waste material recycling methods.
図において、第１図はドライヤー内における熱
風、廃材破砕粒子の温度変化、および廃材破砕粒
子の含水率の変化を示すグラフ、第２図は廃材中
のアスフアルトにおける針入度を示すグラフ、第
３図は廃材中のアスフアルトにおける軟化点を示
すグラフ、第４図は廃材中のアスフアルトにおけ
る伸度を示すグラフである。
In the figure, Figure 1 is a graph showing hot air in the dryer, temperature changes of crushed waste particles, and changes in water content of crushed waste particles, Figure 2 is a graph showing the penetration degree of asphalt in waste materials, and Figure 3 is a graph showing the degree of penetration of asphalt in waste materials. The figure is a graph showing the softening point of asphalt in waste materials, and FIG. 4 is a graph showing the elongation of asphalt in waste materials.
Claims (1)
材に対して約３〜７重量％湿潤させた後、この廃
材破砕粒子をドライヤーに投入すると共に、ドラ
イヤー内におけるその廃材破砕粒子の移動方向に
沿つてドライヤー内に約650〜900℃の熱風を供給
することにより、廃材破砕粒子に湿潤させた水分
によつて廃材中に含まれるアスフアルトの劣化を
防止しながら廃材を加熱再生することを特徴とし
たアスフアルト舗装廃材の再生方法。1. After crushing the asphalt pavement waste material and moistening the waste material with water by about 3 to 7% by weight, the crushed waste particles are put into a dryer, and the crushed waste particles are passed through the dryer along the direction of movement of the crushed waste particles in the dryer. An asphalt pavement that heats and regenerates waste materials by supplying hot air of about 650 to 900 degrees Celsius inside the interior, preventing the asphalt contained in the waste materials from deteriorating due to moisture moistened with crushed waste material particles. How to recycle waste materials.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7327279A JPS55165304A (en) | 1979-06-11 | 1979-06-11 | Regeneration of waste asphalt pavement material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7327279A JPS55165304A (en) | 1979-06-11 | 1979-06-11 | Regeneration of waste asphalt pavement material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS55165304A JPS55165304A (en) | 1980-12-23 |
| JPS6223123B2 true JPS6223123B2 (en) | 1987-05-21 |
Family
ID=13513348
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7327279A Granted JPS55165304A (en) | 1979-06-11 | 1979-06-11 | Regeneration of waste asphalt pavement material |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS55165304A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63142093A (en) * | 1986-12-05 | 1988-06-14 | Niigata Eng Co Ltd | Production of regenerated asphalt compound |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5417927A (en) * | 1977-07-09 | 1979-02-09 | Niigata Engineering Co Ltd | Regenerating method of asphalt concrete |
-
1979
- 1979-06-11 JP JP7327279A patent/JPS55165304A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5417927A (en) * | 1977-07-09 | 1979-02-09 | Niigata Engineering Co Ltd | Regenerating method of asphalt concrete |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS55165304A (en) | 1980-12-23 |
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