Asphalt is often used for paving roads at commercial level as well as residential parking lots of driveways by the asphalt paving companies and also highly recommended by the driveway owners. I think there are people who have seen the scene of paving the road. You may think of a situation where you pour black liquid from the tanker and flatten it with a roller.
However, I think that few people actually saw how asphalt is made. So, this time I will talk about how asphalt is made and introduce the effects of asphalt components on the human body and the benefits of asphalt.
Table of contents
- How is asphalt made
- The ingredients contained in asphalt and the influence on the human body
- The difference with coal tar used for road pavement
- 4 merits to recommend asphalt pavement
How is asphalt made?
There are two major types of asphalt: natural asphalt and petroleum asphalt. Natural asphalt has been used mainly as an adhesive and waterproofing material since ancient times and is produced in various forms, such as being soaked in stone and sand. There are also asphalt lakes in the world, and the largest natural asphalt lake “Pitch Lake” is famous as a lake that has been asphalted rather than water.
Petroleum asphalt, on the other hand, changes depending on the manufacturing method and raw materials, but modified asphalt, etc., in which the polymer is mixed with straight asphalt to improve durability, is used on many roads.
In general, asphalt is produced by vacuum distillation of crude oil.
There are two methods of crude oil distillation: atmospheric distillation, in which the crude oil is directly heated and distilled, and vacuum distillation, in which the heavy fraction is reduced in pressure and distillation.
In atmospheric pressure distillation, LPG, gasoline, kerosene, light oil, etc. with relatively low boiling points are fractionated, and the remaining is vacuum distilled and fractionated into heavy oil, lubricating oil, asphalt, etc. Therefore, asphalt is produced by vacuum distillation of crude oil and is the heaviest, semi-solid black substance among hydrocarbons contained in crude oil.
The ingredients contained in asphalt and their effects on the human body
I think I’ve seen where I’m paving asphalt, but when I pass near it I think that the smoke of asphalt comes out and I care about the peculiar smell. Although this smoke seems to be harmful to the body at first glance, its actual identity is the water vapor that has evaporated the water that cools the asphalt. Also, the smell of wet asphalt is unique on a rainy day, but it is said that the smell is not the smell of asphalt itself, but the smell of dirt and dust adhering to the road. It can be said that the smell of asphalt does not adversely affect the human body. So what is the composition of the asphalt itself?
The main components of asphalt, oils such as paraffin and naphthenic, and resin are widely used in our daily lives. For example, candles and crayons, accessories, and lotions used for hand care. It is widely used, such as being used as a lubricant in factories and so on. It can be said that the ingredients of the asphalt itself are not harmful. Asphalt is often used on roads and parking lots as a material that can be safely used without any impact on the human body.
The difference with coal tar used for road pavement
Coal tar is a by-product of carbonization of coal and is a liquid or semi-solid substance. Coal tar was once used for road pavement, but it is currently replaced by asphalt and concrete pavement. Coal tar contains more than 300 kinds of aromatic compounds such as benzene, carbonic acid, and cresol, among which carcinogenic substances are said to be contained. In particular, benzo (a) pyrene is a relatively large amount of carcinogens contained in coal tar, and when it is taken into the body, a large amount of active oxygen is generated. Active oxygen is necessary for the body. However, if the amount is too large, it has the effect of damaging clean cells, which leads to carcinogenesis.
I tried to summarize the difference between such coal tar and asphalt.
Raw materials and main components
- Asphalt is produced by distillation residue from crude oil and contains hydrocarbons as its main component.
- Coal tar is produced by carbonization of coal and contains more than 300 aromatic compounds such as benzene, carbonic acid, and cresol.
Current main usage
- Asphalt is used directly on the roof, for road pavements, parking lots, and waterproofing purposes.
- Coal tar is used indirectly by taking out ingredients like synthetic fragrances for food, cosmetics, raw materials for fragrances and insect repellents.
Four merits to recommend asphalt pavement
When making a parking lot, it is better to use asphalt than other pavement methods. Let’s introduce it.
1: There is an affordable cost.
2: Soft and flexible, reduce the noise of the car.
3: Since it will be completely solidified when paved and cooled, the work days can be shortened.
4: There is less carcinogenic substance than coal tar and it is safe.
- What did you think? This time, I have introduced the ingredients of asphalt and the effects on people.
- You may have to consider the impact on the human body from the smoke and unique oil odor when paving asphalt.
- However, it turned out that asphalt is safe because it does not contain negative effects. Asphalt that is often used in parking lots and roads.