KR100202526B1 - Asphalt paving - Google Patents

Abstract

In the manufacturing method of asphalt modifier, the residual excess impurities such as unreacted naphthenic acid and sulfur compounds contained therein are reduced to 70-200 under reduced pressure. After distilling off, the remaining volatiles were removed by passage through an inert gas such as nitrogen, and then oils, such as lube base oil, were added to the treated compound to obtain a new low viscosity and odorless asphalt modifier. Asphalt is obtained and 100 ~ 180 before laying during construction with modified asphalt. It is characterized by shortening the curing period by promoting the curing for 1-2 hours.

Description

Method for preparing improved organic metal catalyst-based asphalt modifier and improved asphalt pavement mixture and its construction method

The present invention relates to a method for producing a new asphalt modifier, an asphalt pavement mixture using the same, and a method for constructing the same.

In particular, the present invention relates to a method for preparing an organometallic catalyst-based asphalt modifier soluble in asphalt that is added to asphalt to improve the physical properties of the asphalt, and an asphalt pavement mixture using the modifier and a method of constructing the asphalt pavement mixture.

As a conventional technology for asphalt modification, Korean Patent Publication No. 83-2436 and Korean Patent Publication No. 95-6645 disclose known aggregate after adding and dissolving a special organometallic compound to heating asphalt to improve the physical properties of asphalt. By paving the road with an asphalt pavement composition and such asphalt pavement composition, it is disclosed that the finally cured pavement has improved properties such as increased strength and stability.

The metal component of the organometallic compound is selected from any one of manganese, cobalt, copper, iron or a mixture of two or more selected from the above metals, and the organic component is derived from carboxylic acid, alcohol, phenol or ketone. will be.

As the organometallic compound, a naphthenic acid metal salt is generally used.

In addition, in order to add the organometallic compound as a liquid to the heated asphalt and to maintain the asphalt mixture at a low viscosity, an organic oil is used in combination.

More specifically, known asphalt modifiers are typically prepared by direct melting of naphthenic acid and metal oxides or by metathesis of aqueous solutions of naphthenic acid alkali salts and aqueous metal salts.

Naphthenic acid is obtained as a by-product from petroleum refining and contains small amounts of impurities such as phenols, sulfur compounds such as geophenols and merpentanes.

This impurity is a substance with an irritating odor, and is difficult to be separated by the heavy oil refining process of naphthenic acid, and as a result, remains in the asphalt modifier. Phosphorus 100-160 Has a strong irritating odor.

In addition, the modifier as described above is prepared by a direct melting reaction, so in this reaction, a large amount of unreacted naphthenic acid is contained, thereby increasing the viscosity of the modifier by the unreacted naphthenic acid.

This was a hassle to heat up to the required temperature in order to maintain the viscosity required to add and mix the modifier to the asphalt.

In addition, the conventional asphalt pavement mixture with the addition of the modifier, after pavement at a temperature around the road proceeds at a very slow rate, sometimes it takes several months to fully cure to the deep part of the pavement.

On the other hand, the area within 2 ~ 3cm from the surface of the asphalt pavement to the strata is excessively hardened due to the high temperature of the sun and the influence of oxygen in the air, and the strength difference is severe depending on the depth of the pavement. As a result, microcracking was frequently generated up to a certain depth of the surface of the paving asphalt.

The present invention is to completely improve the defects of the conventional reforming material and the asphalt added thereto, to remove most of the impurities causing irritating odor and to construct a modified and modified asphalt pavement mixture having an appropriate viscosity for asphalt input By different methods to accelerate the hardening of the asphalt pavement mixture in a short time, thereby providing a method for improving the crack resistance of the road surface layer as an example will be described in detail as follows.

In the method for producing an asphalt modifier by reaction of metal oxides such as naphthenic acid with manganese, cobalt, copper, iron, zinc, lead, and barium, or reaction with an aqueous naphthenic acid alkali salt and a metal salt aqueous solution, an excessive amount of fine residue remaining in the reaction product Reactions of impurities such as sulfuric compounds such as naphthenic acid and phenols, geophenols and merpatans contained therein under reduced pressure 70 to 200 , Preferably 110 to 150 The remaining volatiles were separated by distillation at, and then removed by passing through an inert gas such as nitrogen, and the removed naphthenic acid metal compound was converted into a low-viscosity liquid at room temperature and contained bituminous minerals in the petroleum refining process to reduce the temperature sensitivity. A new asphalt modifier is prepared by adding oil, such as lube base oil extracted from a residue, and the asphalt mixture obtained by adding the modifier thus obtained, and the asphalt pavement mixture including the above-described asphalt mixture and other, similar modifiers. 100 ~ 180 at construction It relates to a method for constructing asphalt pavement mixture, characterized in that after laying for 1 hour to 2 hours at a temperature of promote curing before laying.

Since the modified material of the organometallic catalyst asphalt of the present invention constituted as described above is significantly reduced in unreacted naphthenic acid, the viscosity is low, so it is easy to work when added to asphalt without the need for heating separately, and the irritant derived from naphthenic acid. The working environment is improved due to the removal of odor-causing impurities, and the above-mentioned high-temperature promoting curing process before installation can be used to allow traffic to be opened on the road as soon as possible after curing. Of course, the surface of the vehicle is densely compacted due to the traffic, thereby preventing the surface cracking caused by excessive hardening by blocking oxygen supply to the pavement surface.

Example

Existing Modifier Sample A:

The composition and viscosity of existing commercially available modifiers were as follows.

Free acid content (% by weight) 12

Metal content (% by weight), manganese 6.0

Iron 0.92

Viscosity (C PS) 25 5,537

40 1,119

Improved Modifier Sample B:

According to the present invention, the precipitate produced by metathesis reaction between the aqueous solution of naphthene alkaline salt and the aqueous solution of manganese manganese is 120-140. After distilling off the unreacted impurities under reduced pressure for 2 hours at 30 minutes, nitrogen gas was passed from the bottom, and the composition and viscosity were tested by mixing lubricating base oil with a softener.

Free acid content (% by weight) 0.5 or less

Metal content (% by weight) Manganese 6.25%

Viscosity (c ps) 25 1.368

40 418

2 wt% of each of the modified materials A and B as described above are added to the asphalt, followed by mixing with the aggregate having a particle size distribution such that the content of the unmodified and modified asphalt is 5.3%. Mixed in.

At this time, the asphalt mixture to which the existing modifier A was added caused a severe irritating odor.

Asphalt mixture with modified modifier B added (modified mixture B) 150 After 1 hour of incubation, the cores were molded and the existing asphalt mixture (modified mixture A) and the ordinary asphalt mixture (modified mixture A) were added immediately after mixing. Cured in an oven for 14 days.

Marshall stability of each cured mixture, 23 Indirect tensile test and test results for the recovery modulus are shown in Table 2 and Table 3 Table 4.

From the above test results, it can be seen that the toughness exhibiting stability, crack resistance, and the stiffness-promoting effect at high temperatures are greater in the case of accelerated high temperature curing by adding the improved modifier according to the present invention.

Claims (3)

In the method for producing an asphalt modifier by reaction of metal oxides such as naphthenic acid with manganese, cobalt, copper, iron, zinc, lead, and barium, or reaction with an aqueous solution of naphthenic acid alkali and a metal salt, the excess residue remaining in the reaction product Reactions of impurities such as sulfuric compounds such as naphthenic acid and phenols, geophenols and merpatans contained therein under reduced pressure 70 to 200 The remaining volatiles were separated by distillation at and then passed through an inert gas such as nitrogen, and then removed, and the treated naphthenic acid metal compound was converted into a low viscosity liquid at room temperature and subjected to bitumen in the petroleum refining process to reduce temperature sensitivity. A method for producing an organometallic catalyst-based asphalt modifier consisting of adding an oil such as lubricant base oil extracted from the residue. Asphalt pavement composition to which the modifier obtained in Claim 1 was added. 100 ~ 180 for construction using asphalt pavement mixture with modifier added Asphalt pavement mixture construction method characterized in that the laying after promoting curing before laying for 1 to 2 hours at a temperature of.