Separation method of highway waste asphalt pavement materials

Abstract

The invention discloses a method for separating waste and old asphalt pavement materials of highways, and belongs to the technical field of separation of waste and old asphalt pavement materials (RAP). In this method, the waste road asphalt pavement material is first pulverized and dried, and then input into the extractor. After the compound solvent extraction treatment, the asphalt oil and sand and gravel are separated, and the mixed oil formed by the asphalt oil and the compound solvent is evaporated in a distillation pot. Asphalt oil is pumped into the asphalt tank. The evaporated composite solvent gas is condensed and turned into a liquid for recycling. Heat the remaining material in the extractor to 90-130°C, control the vacuum degree to 1.5-3KPa, convert the residual composite solvent in the sand and gravel into gaseous output, and then output the sand and gravel. During the separation process, the road waste asphalt pavement (RAP) is treated with a specific composite solvent and process parameters, the extraction rate of asphalt oil is over 94%, and the asphalt residue in the separated sand and gravel is less.

Description

technical field

[0001] The invention relates to the technical field of separating waste and old asphalt pavement materials for highways, in particular to a method for separating waste and old asphalt pavement materials for highways. Background technique

[0002] Highway waste asphalt pavement (RAP) is the waste asphalt pavement material produced during milling and excavation during highway renovation. Among them, the content of asphalt is 4-5%, and stone materials (coarse aggregate, fine aggregate, mineral powder) account for 95-96%.

[0003] my country's highway mileage is 4.7735 million kilometers, and 340 million tons of waste asphalt pavement (RAP) is produced every year. The Ministry of Transport's "Guiding Opinions on Accelerating the Recycling of Highway Pavement Materials" pointed out that in 2020, the country will achieve "zero waste" of waste road fabric materials.

[0004] At present, waste asphalt materials at home and abroad use cold and hot regeneration treat...

Examples

Embodiment 1

[0032] The present embodiment road waste asphalt pavement material (RAP) separation method, flow process is as follows figure 2 , including the following steps:

[0033] (1) Highway waste asphalt pavement materials (RAP) include asphalt oil, sand and gravel materials, and the content of asphalt oil is 4-5%; the raw materials are transported to the pulverizer by the conveyor, and crushed to particles with a particle size below 50mm; then transported by the conveyor Dried in a dryer, dried and dehydrated at 50-65°C, and transported to the extractor by a conveyor.

[0034] (2) Highway waste asphalt pavement (RAP) is extracted by the composite solvent in the extractor. The composite solvent is placed in the solvent circulation tank, and after being extracted from the solvent circulation tank by the solvent pump, it enters the extractor through the solvent inlet. In; The usage amount of composite solvent is 0.5wt.% of the weight of raw material. The temperature of the extraction...

Embodiment 2

[0038] The difference from Example 1 is:

[0039] The composition of the composite solvent is: No. 120 mineral spirits 60wt.%, petroleum ether 24.5wt.%, n-heptane 15.5wt.%.

[0040] According to the operation steps of Example 1, after the raw material of road waste asphalt pavement (RAP) is separated and extracted, the extraction rate of asphalt is more than 94.2%.

[0041] In the separated sand and gravel, 0.25% of asphalt remains.

technical field

[0001] The invention relates to the technical field of separating waste and old asphalt pavement materials for highways, in particular to a method for separating waste and old asphalt pavement materials for highways. Background technique

[0002] Highway waste asphalt pavement (RAP) is the waste asphalt pavement material produced during milling and excavation during highway renovation. Among them, the content of asphalt is 4-5%, and stone materials (coarse aggregate, fine aggregate, mineral powder) account for 95-96%.

[0003] my country's highway mileage is 4.7735 million kilometers, and 340 million tons of waste asphalt pavement (RAP) is produced every year. The Ministry of Transport's "Guiding Opinions on Accelerating the Recycling of Highway Pavement Materials" pointed out that in 2020, the country will achieve "zero waste" of waste road fabric materials.

[0004] At present, waste asphalt materials at home and abroad use cold and hot regeneration treat...

Examples

Embodiment 1

[0032] The present embodiment road waste asphalt pavement material (RAP) separation method, flow process is as follows figure 2 , including the following steps:

[0033] (1) Highway waste asphalt pavement materials (RAP) include asphalt oil, sand and gravel materials, and the content of asphalt oil is 4-5%; the raw materials are transported to the pulverizer by the conveyor, and crushed to particles with a particle size below 50mm; then transported by the conveyor Dried in a dryer, dried and dehydrated at 50-65°C, and transported to the extractor by a conveyor.

[0034] (2) Highway waste asphalt pavement (RAP) is extracted by the composite solvent in the extractor. The composite solvent is placed in the solvent circulation tank, and after being extracted from the solvent circulation tank by the solvent pump, it enters the extractor through the solvent inlet. In; The usage amount of composite solvent is 0.5wt.% of the weight of raw material. The temperature of the extraction...

Embodiment 2

[0038] The difference from Example 1 is:

[0039] The composition of the composite solvent is: No. 120 mineral spirits 60wt.%, petroleum ether 24.5wt.%, n-heptane 15.5wt.%.

[0040] According to the operation steps of Example 1, after the raw material of road waste asphalt pavement (RAP) is separated and extracted, the extraction rate of asphalt is more than 94.2%.

[0041] In the separated sand and gravel, 0.25% of asphalt remains.

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