JP7191839B2 - asphalt binder - Google Patents

Description

TECHNICAL FIELD The present invention relates to an asphalt binder that is used for reuse of asphalt pavement, and that has good fluidity even at low temperatures such as winter and cold regions.

Conventionally, in the reuse (recycling) of asphalt pavement, an additive for asphalt regeneration is used. The reason for this is the restoration of the properties of the deteriorated asphalt existing in the asphalt pavement after use. It is known that the aromatic content in asphalt decreases as the asphalt deteriorates (Tomonishi Tomonishi, ``Study on the physical and scientific characteristics of modified asphalt'', Public Works Research Center 1994 Department Outside Researcher's Report Summary Version, June 1995, p.167-170, Daisaku Tateishi, ``Study on the Physical and Scientific Properties of Modified Asphalt'', Public Works Research Center 1994 Outside Researcher Report Summary Version , June 1996, p.229-232). For this reason, a highly aromatic mineral oil such as an extract is sometimes added to compensate for the aromatic content.

However, additives with high aromatic content exhibit high viscosities. Therefore, there is a problem that the fluidity of the additive is poor and workability is lowered. In addition, when the viscosity of the additive is lowered, the flash point and density tend to be lowered, so problems arise in terms of safety and miscibility with deteriorated asphalt.

In this respect, Patent Document 1 proposes an asphalt binder (binder composition) that improves the fluidity at room temperature without reducing the aromatic content. In Patent Document 1, since the complex elastic modulus at 0.1 rad/sec at 25° C. is set to 10.00 Pa or less, it has excellent fluidity at room temperature and improves workability compared to conventional additives. An asphalt binder capable of

JP-A-2008-56742

However, when the asphalt binder disclosed in Patent Document 1 is used at low temperatures (for example, 0° C.) in winter or in cold regions, the viscosity increases and the fluidity becomes poor. As a result, there arises a problem that workability is lowered at low temperatures.

Therefore, the present invention has been devised in view of the above-mentioned problems, and its object is to provide an asphalt binder that suppresses the deterioration of workability even at low temperatures such as winter. .

In order to solve the above problems, the asphalt binder according to claim 1 contains solvent-extracted oil: less than 73.0% by weight, lubricating base oil: 27.0% by weight or more, and asphalt. , The relationship between the content Y of the asphalt and the content X of the lubricating base oil is 1.25 × X-32 ≤ Y ≤ 1.25 × X-25.375, and Y ≤ -13.3 It is characterized by satisfying xX+437.06 and having a complex elastic modulus of 10.0 Pa or less at 0° C. and 0.1 rad/sec.

The asphalt binder of claim 2 is characterized in that, in the invention of claim 1, the asphalt is at least one of solvent deasphalted asphalt and straight asphalt.

The asphalt binder according to claim 3 is the invention according to claim 1 or 2, wherein the kinematic viscosity of the lubricating base oil is 80.0 mm ² /sec or more and 110.0 mm ² /sec or less at 40 ° C. and 100 ° C. is 9.0 mm ² /sec or more and 13.0 mm ² /sec or less.

The asphalt binder having the above configuration to which the present invention is applied has a complex elastic modulus of 10.0 Pa or less at 0° C. and 0.1 rad/sec. Therefore, it has excellent fluidity even at low temperatures such as in winter or in cold regions. Thereby, it is possible to suppress deterioration of workability even at low temperatures.

Moreover, the asphalt binder to which the present invention is applied contains a large amount of solvent-extracted oil and a large amount of aromatic components. Therefore, it is possible to supplement the aromatic content of the deteriorated asphalt. As a result, a recycled asphalt pavement having properties equivalent to those of new asphalt pavement can be obtained.

In addition, the asphalt binder having the above-described structure to which the present invention is applied has a flash point of 260° C. or higher, and safety during work can be ensured.

FIG. 1 is a diagram plotting the relationship between the content of lubricating base oil and the content of asphalt.

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of an asphalt binder (hereinafter referred to as a binder composition ) to which the present invention is applied will be described in detail below.

The present inventor has found that the binder composition used as a softening agent for asphalt regeneration, a rubber extension oil, a rubber compounding oil, etc. has good fluidity even at low temperatures and suppresses deterioration of workability. , conducted intensive experimental research. As a result, under such conditions of use, particularly when it begins to flow, a very slow force (gravity if flowing out of a storage container, pressure if transported by a pump) acts on the binder composition. Therefore, at 0 ° C., the complex elastic modulus is measured at a slow frequency of 0.1 rad / sec (0.0159 Hz), and if the value is 10.0 Pa or less, it is sought in these works It was found that fluidity can be obtained. Furthermore, conventionally, when a lubricating base oil and asphalt are added to a solvent-extracted oil that has been used as an additive for asphalt, the complex elastic modulus at 0.1 rad / sec at 0 ° C. is 10.0 Pa or less. The discovery led to the present invention.

That is, the binder composition to which the present invention is applied contains less than 73.0% by weight of solvent-extracted oil, 27.0% by weight or more of lubricating base oil, and asphalt. In addition, the relationship between the asphalt content Y and the lubricant base oil content X is 1.25 x X-32 ≤ Y ≤ 1.25 x X-25.375 and Y ≤ -13.3 x Meets X+437.06. The complex elastic modulus at 0.1 rad/sec at 0° C. is 10.0 Pa or less.

The reasons for numerical limitations in the binder composition to which the present invention is applied will be described below.

<Solvent-extracted oil: less than 73.0% by weight>
Solvent-extracted oil is a component that contains a large amount of aromatics and is added mainly to supplement the aromatics of deteriorated asphalt and acts as a softening agent. Solvent-extracted oil is an extracted oil produced in the solvent extraction process when producing lubricating oil from crude oil, and is an oily substance rich in aromatics and naphthenes (“How petroleum products are made”, Fig. 6 -1 "General Lubricating Oil Manufacturing Process", Petroleum Association of Japan, November 1971, p.99, and "New Oil Dictionary", The Petroleum Institute, 1982, p. The content of the solvent-extracted oil is 73.0% by weight or less, and is used as the base material of the binder composition to which the present invention is applied. Therefore, the binder composition to which the present invention is applied can contain a large amount of aromatic components.

When the solvent-extracted oil content is 73.0% by weight or more, the complex elastic modulus of the binder composition increases. Therefore, the fluidity of the binder composition is poor at low temperatures, resulting in poor workability. Therefore, the content of solvent-extracted oil should be less than 73.0% by weight. The solvent-extracted oil preferably has a kinematic viscosity of 400.0 to 600.0 mm ² /sec at 60°C and a density of 0.960 to 0.990 g/cm ³ at 15°C. More preferably, the density at 15°C is 0.970 to 0.980 g/cm ³ .

<Lubricating base oil: 27.0% by weight or more>
Lubricating base oils are added primarily to reduce the kinematic viscosity of solvent-extracted oils. As a method for producing the lubricating base oil, for example, the propane deasphalting method is used to extract the deasphalted oil from the vacuum distillation residue, the solvent extraction method is used to extract the refined oil from the deasphalted oil, and the solvent dewaxing method is used to extract the dewaxed oil from the refined oil, and a hydrorefining process is used to produce the lubricant base oil from the dewaxed oil. The content of the lubricating base oil is 27.0% by weight or more. Therefore, the binder composition to which the present invention is applied can sufficiently reduce the kinematic viscosity of the solvent-extracted oil, and can maintain the complex elastic modulus at 0° C. and 0.1 rad/sec at 10.0 Pa or less. can.

When the content of the lubricating base oil is less than 27.0% by weight, the kinematic viscosity of the solvent-extracted oil cannot be sufficiently lowered, and the complex elastic modulus of the binder composition increases. Therefore, the fluidity of the binder composition is poor at low temperatures, resulting in poor workability. Therefore, the content of the lubricating base oil is set to 27.0% by weight or more. The lubricating base oil has a kinematic viscosity of 80.0 mm ² / sec or more and 110 mm ² / sec or less at 40 ° C. and 9.0 mm ² / sec or more and 13.0 mm ² / sec or less at 100 ° C. Density at 15 ° C. is 0.870 to 0.890 g/cm ³ and the flash point is 230° C. or higher.

<The relationship between the asphalt content Y and the lubricating base oil content X satisfies Y ≤ 1.25 × X-25.375>
Asphalt is added primarily to improve fluidity in mixtures of solvent-extracted oils and lubricating base oils. Examples of asphalt include straight asphalt (see JIS K 2207), blown asphalt (see JIS K 2207), semi-blown asphalt (“Guidelines for Asphalt Pavement”, published by the Japan Road Association, January 13, 1997, p.51 , Table-3.3.4), solvent-deasphalted asphalt (see "New Oil Dictionary", edited by Japan Petroleum Institute, 1982, p.308), or a mixture thereof. The relationship between the asphalt content Y and the lubricating base oil content X satisfies Y ≤ 1.25 × X-25.375, so that the binder composition to which the present invention is applied has a 0.1 rad at 0 ° C. /sec can be kept below 10.0 Pa.

When the relationship between the asphalt content Y and the lubricating base oil content X is Y>1.25×X−25.375, the asphalt content in the binder composition is too large, so the solvent Inhibits improvement of fluidity in a mixture of extracted oil and lubricating base oil. Therefore, there is a tendency for the mixture dispersion of the binder composition to increase. This increases the possibility that the complex elastic modulus of the binder composition will increase, resulting in poor fluidity and poor workability. Therefore, in order to obtain stable properties of the binder composition, the relationship between the asphalt content Y and the lubricating base oil content X should satisfy Y ≤ 1.25 × X - 25.375. .

In the binder composition to which the present invention is applied, it is desirable to use at least one of solvent-deasphalted asphalt and straight asphalt. Straight asphalt refers to asphalt obtained by vacuum distillation of atmospheric distillation residue oil. Since solvent-deasphalted asphalt has a higher density than other asphalts, it is possible to improve the density of the binder composition. Solvent-deasphalted asphalt also has a higher aromatic content than other asphalts. Therefore, it is possible to supplement the aromatic content of the deteriorated asphalt. The solvent deasphalted asphalt has a penetration of 3 to 20 (0.1 mm), a softening point of 56.0 to 70.0 ° C., and a density of 1.060 to 1.070 g / cm ³ at 15 ° C. At least one of them is desirable.

<The relationship between the asphalt content Y and the lubricating base oil content X satisfies Y≧1.25×X-32>
In the binder composition to which the present invention is applied, the relationship between the asphalt content Y and the lubricating base oil content X satisfies Y≧1.25×X-32. Therefore, the density of the binder composition to which the present invention is applied can be maintained at 0.950 g/cm ³ or more at 15°C.

When the relationship between the asphalt content Y and the lubricating base oil content X is Y<1.25×X-32, the ratio of the asphalt content to the lubricating base oil content decreases. This reduces the density of the asphalt composition. This creates problems with miscibility with degraded asphalt. Therefore, the relationship between the asphalt content Y and the lubricant base oil content X in the binder composition satisfies Y≧1.25×X−32.

<The relationship between the asphalt content Y and the lubricating base oil content X satisfies Y ≤ -13.3 × X + 437.06>
In the binder composition to which the present invention is applied, the relationship between the asphalt content Y and the lubricant base oil content X satisfies Y≦−13.3×X+437.06. Therefore, the aromatic content of the binder composition to which the present invention is applied can be maintained at 50.00% or more.

If the relationship between the asphalt content Y and the lubricating base oil content X is Y>-13.3 × X + 437.06, the solvent-extracted oil content for the lubricating base oil content and the asphalt content The content ratio becomes smaller. As a result, the content of aromatics in the asphalt composition is reduced. This creates problems with miscibility with degraded asphalt. Therefore, the relationship between the asphalt content Y and the lubricant base oil content X in the binder composition satisfies Y≦−13.3×X+437.06.

Based on the above, the relationship between the content Y of asphalt and the content X of the lubricating base oil is 1.25 × X-32 ≤ Y ≤ 1.25 × X-25.375, and Y ≤ -13 .3×X+437.06 is satisfied.

<The complex elastic modulus at 0.1 rad/sec at 0°C is 10.0 Pa or less>
As described above, the present invention aims at suppressing deterioration in workability during work in which a slow force acts at a low temperature of around 0°C. In order to achieve this task, when the complex elastic modulus at 0.1 rad/sec at 0° C. exceeds 10.0 Pa, there is almost no flow at low temperatures. This reduces workability, for example, when pouring out of a storage container and during pumping. Therefore, the binder composition to which the present invention is applied has a complex elastic modulus of 10.0 Pa or less at 0° C. and 0.1 rad/sec.

The complex elastic modulus G ^* was measured according to the dynamic shear rheometer (DSR) test method stipulated in the Handbook of Pavement Investigation and Test Methods (edited by the Japan Road Association). The measurement principle of this test is that the binder composition is sandwiched between two parallel discs (50 mm in diameter), a sinusoidal strain of a predetermined frequency (10% strain) is applied to one of the discs, and the binder composition (thickness The sinusoidal stress σ that is transmitted to the other disk via a 1-mm thick disk is measured, and the complex elastic modulus is obtained from the sinusoidal stress and the sinusoidal strain. Then, based on the measurement results, the complex elastic modulus G ^* is obtained from the following formula (1). Here, γ in the following formula (1) is the maximum strain applied to the parallel discs.

<The kinematic viscosity of the lubricating base oil is 80.0 mm ² /sec or more and 110.0 mm ² /sec or less at 40°C, and 9.0 mm ² /sec or more and 13.0 mm ² /sec or less at 100°C>
The kinematic viscosity of the lubricating base oil is 80.0 mm ² / sec or more and 110.0 mm ² / sec or less at 40 ° C. and 9.0 mm ² / sec or more and 13.0 mm ² / sec or less at 100 ° C. is desirable. If the kinematic viscosity of the lubricating base oil is less than at least one of 80.0 mm ² / sec at 40 ° C. and 9.0 mm ² / sec at 100 ° C., the flash point of the lubricating base oil becomes too low, and the binder composition The flash point of the substance becomes less than 250°C, which worsens the safety during work and increases the difficulty of storage. If it exceeds at least one of 110.0 mm ² /sec at 40°C and 13.0 mm ² /sec at 100°C, the kinematic viscosity of the lubricating base oil becomes too high, making handling difficult. Therefore, the kinematic viscosity of the lubricating base oil is 80.0 mm ² / sec or more and 110.0 mm ² / sec or less at 40 ° C. and 9.0 mm ² / sec or more and 13.0 mm ² / sec or less at 100 ° C. is desirable.

As described above, the binder composition to which the present invention is applied has a complex elastic modulus of 10.0 Pa or less at 0° C. and 0.1 rad/sec. Therefore, it has excellent fluidity at low temperatures, and can improve workability in operations where slow force acts, such as outflow from a storage container and pump transfer.

The flash point of the binder composition affects safety during work and difficulty of storage. If the flash point of the binder composition is less than 250° C., it falls under the category of hazardous materials (class 4 class 4 petroleum), resulting in deterioration of safety during work and increased difficulty of storage. Therefore, the binder composition to which the present invention is applied preferably has a flash point of 250° C. or higher.

The binder composition to which the present invention is applied includes, in addition to the base material solvent-extracted oil, lubricating base oil, and asphalt, for example, a saturated fatty acid or unsaturated fatty acid having 12 to 22 carbon atoms, or a mixture thereof, or In addition to containing dimers, these amides and polymers may also be contained.

EXAMPLES The characteristics of the binder composition to which the present invention is applied will be specifically described below with reference to examples and comparative examples.

In this example, the solvent-extracted oil, the lubricating base oil, and the asphalt were mixed in the proportions shown in Table 1 below to prepare the binder compositions of the examples and comparative examples, and the complex elastic modulus, density, and aroma Family content was measured.

As a solvent-extracted oil, the density at 15° C. is 0.975 g/cm ³ , the viscosity at 40° C. is 2902 mm ² /s, the viscosity at 60° C. is 485 mm ² /s, the flash point is 332° C., and the aromatic content is 73.2. % and an aniline point of 70.2°C.

As lubricating base oils, kinematic viscosities of 87.92 mm ² /s at 40°C, 36.57 mm ² /s at 60°C and 10.66 mm ² /s at 100°C, density at 15°C of 0.875 g/cm ³ , a pour point of −12.5° C., a flash point of 260° C. and an aromatic content of 2.6% were used.

As the asphalt (1), solvent deasphalted asphalt having a penetration of 12, a softening point of 65.0° C., a density of 1.060 g/cm ³ at 15° C., a flash point of 362° C., and an aromatic content of 67.9%. used. As the asphalt (2), straight asphalt having a penetration of 64, a softening point of 49.0° C., a density of 1.034 g/cm ³ at 15° C., and an aromatic content of 58.0% was used.

The complex elastic modulus was measured according to the DSR test method described above. Density was measured according to JIS K2249.

The aromatic content was measured under the conditions of JPI-5S-70-10 "Asphalt composition analysis test method by TLC/FID method".

FIG. 1 is a diagram plotting the relationship between the lubricating base oil content and the asphalt content in Examples 1 to 12 and Comparative Examples 1 to 13, based on the values in Table 1. Numerical values around the plot indicate the complex elastic modulus (the unit Pa is omitted) at 0.1 rad/sec at 0°C. The solid line in FIG. 1 shows the lower boundary line of the lubricating base oil content, the dashed line shows the upper boundary line between the asphalt content and the lubricating base oil content, and the dashed line is 1 shows the lower boundary line in relation to the content of asphalt and the content of lubricating base oil.

<Lubricating base oil: Examples of 27.0% by weight or more>
As shown in Table 1 and FIG. 1, as shown in Comparative Examples 2 and 3, when the content of the lubricating base oil is less than 27.0% by weight, the content of the solvent-extracted oil with respect to the content of the lubricating base oil proportion of quantity increases. Therefore, the kinematic viscosity of the solvent-extracted oil cannot be sufficiently reduced, and the complex elastic modulus exceeds 10.0 Pa at 0° C. and 0.1 rad/sec. As a result, the complex elastic modulus of the binder composition is increased, the fluidity at low temperatures is poor, and the workability is reduced.

On the other hand, in Examples 1 to 12 in which the content of the lubricating base oil was 27.0% by weight or more, the increase in the ratio of the content of the solvent-extracted oil to the content of the lubricating base oil was suppressed. Therefore, the dynamic viscosity of the solvent-extracted oil can be sufficiently lowered, and the complex elastic modulus at 0° C. and 0.1 rad/sec is 10.0 Pa or less. As a result, the binder compositions of Examples 1 to 12 are excellent in fluidity at low temperatures, and it is possible to suppress deterioration in workability.

<Example where the relationship between the asphalt content Y and the lubricating base oil content X satisfies Y ≤ 1.25 × X-25.375>
In Comparative Examples 4 to 6 and 11 to 13, the boundary line Y = 1.25 × X - 25.375 in the relationship between the asphalt content Y and the lubricating base oil content X is plotted above and the complex elastic modulus at 0.1 rad/s at 0° C. exceeds 10.0 Pa. Therefore, the binder compositions of Comparative Examples 4 to 6 and 11 to 13, which do not satisfy the relationship of Y≦1.25×X−25.375, have poor fluidity at low temperatures, resulting in poor workability.

On the other hand, in Examples 1 to 12, Y≦1.25×X−25.375 is satisfied, and the complex elastic modulus at 0.1 rad/sec at 0° C. is 10.0 Pa or less. Therefore, the binder compositions of Examples 1 to 12 are excellent in fluidity at low temperatures, and it is possible to suppress deterioration of workability.

<Example where the relationship between the asphalt content Y and the lubricating base oil content X satisfies Y≧1.25×X-32>
In Comparative Examples 1 and 10, the boundary line Y = 1.25 × X-32 in the relationship between the asphalt content Y and the lubricating base oil content X is plotted below the density at 15 ° C. is less than 0.950 g/cm ³ . For this reason, the binder compositions of Comparative Examples 1 and 10, which do not satisfy the relationship of Y≧1.25×X-32, have a low density of the asphalt composition and have a problem in mixing with deteriorated asphalt.

On the other hand, Examples 1 to 12 satisfy Y≧1.25×X−32 and each have a density of 0.950 g/cm ³ or more at 15° C. Therefore, in the binder compositions of Examples 1 to 12, deterioration of miscibility with deteriorated asphalt can be suppressed.

<Example where the relationship between the asphalt content Y and the lubricating base oil content X satisfies Y ≤ -13.3 × X + 437.06>
In Comparative Examples 7 to 9, the boundary line Y = -13.3 × X + 437.06 in the relationship between the asphalt content Y and the lubricating base oil content X is plotted above, and the aromatic The content is less than 50.00%. Therefore, in the binder compositions of Comparative Examples 7 to 9, which do not satisfy the relationship Y ≤ -13.3 × X + 437.06, the content of aromatics in the asphalt composition is low, and the mixture with deteriorated asphalt Gender problems arise.

On the other hand, in Examples 1 to 12, Y≦−13.3×X+437.06 is satisfied, and the aromatic content is 50.00% or more. Therefore, in the binder compositions of Examples 1 to 12, deterioration of miscibility with deteriorated asphalt can be suppressed.

As described above, the binder composition to which the present invention is applied contains less than 73.0% by weight of solvent-extracted oil, 27.0% by weight or more of lubricating base oil, and asphalt. In addition, the relationship between the asphalt content Y and the lubricant base oil content X is 1.25 x X-32 ≤ Y ≤ 1.25 x X-25.375 and Y ≤ -13.3 x Meets X+437.06. The complex elastic modulus at 0.1 rad/sec at 0° C. is 10.0 Pa or less. Therefore, it has excellent fluidity even at low temperatures such as in winter or in cold regions. Thereby, it is possible to suppress deterioration of workability even at low temperatures.

Moreover, the binder composition to which the present invention is applied contains a large amount of solvent-extracted oil as a base material and contains a large amount of aromatic components. Therefore, it is possible to supplement the aromatic content of the deteriorated asphalt. As a result, a recycled asphalt pavement having properties equivalent to those of new asphalt pavement can be obtained.

Moreover, the binder composition to which the present invention is applied has a flash point of 250° C. or higher. This makes the asphalt safer and therefore easier to handle and store.

In addition, the kinematic viscosity of the lubricating base oil contained in the binder composition to which the present invention is applied is 80.0 mm ² /sec or more and 110.0 mm ² /sec or less at 40 ° C. and 9.0 mm ² /sec at 100 ° C. second or more and 13.0 mm ² /second or less. This makes it possible to suppress variations in material properties and easily suppress deterioration in workability at low temperatures.

In addition, the binder composition to which the present invention is applied may be used in an environment other than low temperature.

While embodiments of the invention have been described, these embodiments have been presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and modifications can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the scope of the invention described in the claims and equivalents thereof.

Claims (3)

solvent-extracted oil: less than 73.0% by weight;
Lubricating base oil: 27.0% by weight or more,
asphalt and
contains
The relationship between the content Y of the asphalt and the content X of the lubricating base oil is 1.25 x X-32 ≤ Y ≤ 1.25 x X-25.375 and Y ≤ -13.3 x satisfies X+437.06,
An asphalt binder having a complex elastic modulus of 10.0 Pa or less at 0°C and 0.1 rad/sec. 2. The asphalt binder according to claim 1, wherein the asphalt is at least one of solvent-deasphalted asphalt and straight asphalt. The kinematic viscosity of the lubricating base oil is 80.0 mm ² /sec or more and 110.0 mm ² /sec or less at 40 ° C. and 9.0 mm ² /sec or more and 13.0 mm ² /sec or less at 100 ° C. 3. The asphalt binder according to claim 1 or 2.

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