BITUMEN TYPES

Bitumen Types

Petroleum bitumen is a viscous and black substance that consists of a large number of hydrocarbons and is solid or semi-solid at ambient temperature. Petroleum bitumen is produced in the process of crude oil distillation and refining in an oil refinery in a distillation tower.

In oil-rich countries, mostly transfer crude oil to refineries through pipelines to avoid the additional costs of transporting it by oil tankers.

when the crude oil arrived at the refinery; Before starting to refine it, first heat it in preheater ovens to about 350 degrees Celsius then it is sent into the distillation tower, so that in the refining stages, according to the characteristics of the crude oil, by applying different temperatures and pressures in the distillation tower, various products are produced as described below.

1. First, lighter materials such as Benzene and propane are separated at a pressure close to one atmosphere of crude oil and sent to special tanks to store those products.
2. In the second step, heavy materials such as Gasoline and kerosene are separated from the distillation tower under a pressure close to a vacuum and sent to special storage tanks for those products.
3. In the third stage, a mixture of oil, grease, and bitumen remains at the bottom of the distillation tower, which is separated by special operations.
4. In the end, the heavier material remains at the bottom of the distillation tower, which is the bitumen material, which is produced in this stage by performing the vacuum bottom operation (blowing air) in the distillation tower. In the following, we will describe different Bitumen types:

What Are Bitumen Types?

The Crude oil resources available in every region and country and according to the unique characteristics there; Such as the type of land and the type of soil layers are different, as a result, the crude oil available there also contains different characteristics from other crude oil sources in other regions; As a result, the bitumen that is produced in those refineries; They also have different characteristics; For this reason, the experts of the oil industry, by conducting tests on different types of bitumen samples and different types of crude oil and their purification stages in crude oil refineries, and according to the results of the tests of the bitumen samples, produced a total of “bitumen products”.

They have been classified into 8 categories, which we will explain below:

The tests performed on bitumen samples are as follows:

1 – Viscosity GRADE Viscosity classification

2- Classification of bitumen by PERFORMANCE GRADE method

3- Bitumen by GRADE PENETRATION method

4- Grading by CUT-BACK method

5- Classification by EMULATION method

6- OXIDIZED classification by OXIDIZING method

7- Testing to determine the SOFTENING POINT of bitumen SOFTENING POINT

8- FLASH POINT test

Classification bitumen Types by VISCOSITY method

By performing the viscosity test on the bitumen sample VISCOSITY TEST, the viscosity of the bitumen can be determined; Also, by performing the viscosity grades test, four types of bitumen with grades 10, 20, 30, and 40 are produced. It should be noted that in the test of this bitumen, the lower number obtained, the lower viscosity of the bitumen, and the higher number refer to the higher viscosity of the bitumen. Also, these are the types of bitumen VG. with the viscosity of  VG 10, VG 20, VG 30, and VG 40, where VG30 and VG40 are mostly used for repairing sidewalks and road construction.

At the same time, another type of bitumen called AC 30 is produced through viscosity testing, and most consumers of this bitumen are in American countries.

The characteristics of bitumen AC 30 are similar to bitumen VG 30 But bitumen VG 30 has a very high consumption due to the climatic conditions of India.

Classification of bitumen Types by PERFORMANCE method

In the past, for the preparation of asphalt according to the climatic conditions and the number of changes in heat and cold and the resistance of the asphalt to hardening and brittleness of the bitumen, which caused cracking and cracking of the asphalt in the cold, as well as the shrinkage of the asphalt in the heat due to the traffic of trucks and trailers carrying heavy loads; asphalt suppliers used to two methods, they paid attention to bitumen properties such as bitumen penetration grade and viscosity grade.

In these two methods, road builders deal with problems such as breakage, cracking, and short life of asphalt; contractors used to increase the thickness of the asphalt layer to cover the roads, which increases the costs, such as the preparation of asphalt bitumen, and the cost of transportation and implementation, which is not economically viable.

For this purpose, to reduce the costs and problems mentioned above. Exhibition and experts in different countries in the field of performance of all types of bitumen and taking into account climatic conditions and factors such as heat and cold in different areas.

To choose the appropriate bitumen for the production of high-quality asphalt suitable for different areas and to prevent and reduce the number of problems such as aging, fatigue, and hardening of the bitumen, short life of the asphalt, cracking and rutting of the asphalt due to the cold environment, as well as the porosity, crumbling and tearing of the asphalt and the spreading of sand and pebbles on the ground of the roads, as this would cause the destruction of the road and in addition, it would impose a lot of money to repair the roads; On the other hand, it has caused a lot of damage to cars and sometimes caused vehicle accidents and caused casualties to the occupants. They carried out various investigations and tests.

Also, American experts and engineers, in a program called strategic research and review of highways, carried out tests related to the quality and proper performance of asphalt for long life, road safety, and determining the physical characteristics of asphalt. These reviews and tests are the preparation of a new method of tar classification; In the name of classification by the bitumen performance grade method, which is abbreviated as PG, in this method, the necessary parameters such as resistance to changes in various forms, resistance to cracking due to cold environment, resistance to cracking due to fatigue and Investigating the causes of bitumen hardening during the preparation of asphalt in asphalt factories; investigating the causes of hardening bitumen due to the passage of time; examined; So that the type of bitumen that is used for the preparation of asphalt that is used in different regions and according to the different weather conditions and taking into

account the traffic load of that road is a suitable type of bitumen so that it does not have the numerous problems that have been mentioned.

Below is your attention to

The classification table of bitumen with penetration degree is done by the performance method

PENETRATION test method

Classification of bitumen is done by penetration method by testing on bitumen sample in the following way.

First, we heat the tested bitumen to about 60 degrees or above the softening point, then we pour it into a special container with a diameter of 6 cm and a height of 4 cm, then we put it inside the water bath whit a temperature of 25 degrees Celsius for 1.5 hours until the temperature of the sample bitumen is equal to the temperature of the bath water. Then we take it out and put it inside the bitumen penetration testing device. First, we set the device to zero, the chronometer stops, and the 100gram needle is released for 5 seconds, and we read the amount of penetration of the needle into the bitumen and note down this process 5 to 10 times in order to reduce the error and the accuracy of the operation in this test, and every time the penetration of the needle is repeated In the case of bitumen, we remember that the average number obtained from the above test is the amount of penetration degree of bitumen; container containing bitumen from the hot water bath

As seen in the above test, the classification of bitumen penetration is determined by testing on bitumen samples, and in these tests, the more the size of the test needle goes down in the bitumen sample, the larger the number obtained from this test is. The obtained number is smaller and the bitumen is stronger and suitable for road construction projects in tropical regions; penetration grade bitumen has thermoplastic properties and soften at high temperature and harden at low temperature, which is a unique issue in viscosity-temperature at the time determining points such as adhesion and durability in bitumen performance.

These bitumens are displayed as Bitumen 60/70, Bitumen 80/100, Bitumen 85/100, Bitumen 40/50, and Bitumen 30/40, and bitumen with penetration degree is said, as mentioned above, bitumen with low penetration degree area used in hot areas. Bitumen with a high degree of penetration is used in cold regions.

Many companies have made bitumen penetration testers, a model of which is shown below.

Bitumen penetration test device:

Bitumen 40/60

a type of bitumen; 40/60 penetration grade bitumen is one of the categories of infiltration grade that is in accordance with international standards EN12591-2009 and used to produce hot asphalt; It is used in road construction projects.

Bitumen 40/50

a type of bitumen; 40/50 penetration grade bitumen is a category of penetration grade bitumen that is in accordance with the standard ASTMD946-09 and is used for the production of hot asphalt and is often used in road construction projects in warm areas.

Bitumen 50/70

50/70 is bitumen with a penetration grade that is in accordance with the European standard EN12591-2009 and it is used to prepare hot asphalt and its most consumption is garlic in hot areas.

Bitumen 60/70

60/70 is a type of bitumen with a penetration grade that is according to the international standard ASTMD946-09 and is always used in the preparation of hot asphalt and is mostly used in road construction projects in regions with moderate weather. It is possible, and it is also important for the preparation of emulsifying bitumen and soluble bitumen.

Bitumen 60/90

60/90 is a type of penetration grade bitumen that is according to the European standard and is used to prepare hot asphalt and is mostly used in road construction projects in temperate regions.

Bitumen 70/100

70/100 is a graded type of permeation grade that is according to the international standard EN12591-2009 and is used to prepare hot asphalt and is mostly used in road construction projects in cold areas.

Bitumen 80/100

80/100 is a type of bitumen with a penetration grade that is according to the international standard; It is used to produce hot asphalt, And it is mostly used in cold regions and in road construction projects.

80/100 permeability grade bitumen has thermoplastic properties and is similar to synthetic resin, it becomes softer when heated and hardens when cooled; It has a penetration degree of 80-100 and very high viscosity.

Bitumen 85/100

85/100 is a type of bitumen with penetration grade according to the standard ASTMD946-09; It is used to produce hot asphalt, And it is mostly used in very cold areas and in road construction projects.

CUT BACK BITUMEN

Cutback bitumen is another type of bitumen that is obtained in the process of refining crude oil and combining that bitumen with solvents such as petrol, gasoline, diesel, and kerosene in the refinery. The obtained cutback bitumen is liquid and its viscosity is lower. This bitumen is liquid at ambient temperature.

Cutback bitumen is suitable for cold areas and does not need to be heated before use.

 EMULSION BITUMEN

Emulsion bitumen is produced from a mixture of 60% bitumen and 40% water, and like cutback bitumen, it is toxic and harmful, and it does not harm the environment and humans, and it does not need to be heated when using it, it is water resistant, and it evaporates when using water, and it is very easy to transport, and for the same reason, it reduces the cost and from the point of view. It is economical and affordable.

OXIDIZED BITUMEN

Oxidized bitumen is produced in the process of blowing air into bitumen in the refinery.

Blowing air into the bitumen increases the rubber properties of the bitumen and increases its flexibility, durability, and resistance to water. This bitumen is widely used in industry, and it is also widely used for insulation and coating of pipes, flooring, and insulation of the ceiling and floor of bathrooms, kitchens, and paint industries.

Bitumen SOFTENING POINT Test

In this test, we determine the maximum degree of softness and the degree of heat at which bitumen reaches the maximum degree of softness, and usually, this test should be done 4 hours after sampling.

The equipment needed for this test includes:

1. Special mold for bitumen sample according to standard
2. Special grease
3. Glass beaker with a volume capacity of 600 ml of water
4. Distilled water with a temperature of 5 degrees Celsius
5. Ice as needed
6. Mold clip
7. Heater mixer for heating

First, I coat the inside of the mold with special grease, and then we pour the bitumen sample at the appropriate temperature into the mold and wait for 30 minutes until the bitumen inside the mold cools down to the temperature of the laboratory environment, then we pour 500 CC of distilled water at 5 degrees Celsius into a glass beaker, mold clip, and a special thermometer. We put the soft point inside the beaker and add ice to bring the temperature of the distilled water to 5 degrees Celsius, then we put the bitumen sample mold on the clamp and put the bullet clips and pellets on the bitumen sample, and wait for 15 minutes until it stays at 5 degrees Celsius.

Then we put the glass container on the heater equipped with a stirrer and start heating the glass container so that the temperature of the water increases by 5 degrees Celsius every minute. We continue this process of heating the water until the bitumen in the mold becomes completely soft and the metal balls on the bitumen hit the bottom of the mold, and the moment the balls hit the bottom plate of the mold, we record the temperature of the water, and we call this temperature the soft point temperature of the bitumen.

Bitumen FLASH POINT Test Method

How do we know that bitumen is a flammable product in terms of safety and protection of the lives of people who work with it, as well as protection and prevention of the possibility of bitumen exposure in environments such as asphalt factories, bitumen storage tanks, and bitumen trucks; It is necessary to know the Flash point of ignition degree and burning degree of bitumen, and this is important by performing tests on bitumen samples to determine the things we mentioned; Fortunately, today with the advancement of science; Many companies have started making modern devices in this field.

If the tested bitumen sample is lumpy or slightly melted, heat it up to 176 degrees Celsius until it becomes molten bitumen, then pour some of it into the test cup of the device up to the point marked, and if there are bubbles on the surface of the bitumen inside the cup,

remove them. And we wait for the glass inside the cup to cool down to the ambient temperature of the laboratory; After the bitumen cools down, test it in the testing machine

We set the temperature adjustment button of the device so that the temperature is heated to 7.16 degrees Celsius per minute and we continue this until the temperature reaches 56 degrees Celsius at this stage; We reduce the heating speed so that the bitumen heats up by 5 degrees Celsius every minute, and now for every three degrees that the bitumen heats up, we pass a flame through the surface of the bitumen once every second. And we continue the heating steps in the same way and pass the flame every three degrees over the surface of the bitumen until a flame appears at one point on the surface of the bitumen; It is reminded that this appeared flame is transient and we remember this temperature because this temperature is the ignition point of bitumen; Now if you continue heating Let’s go through this stage and reach the temperature of the bitumen fire, where the bitumen inside the cup starts to burn, and it is called the temperature of the bitumen fire. To prevent the test device from catching fire, at this stage, we must put a cap on the test cup to prevent oxygen from entering it and the fire will be suffocated and extinguished. And as can be seen from the test process, the fire point temperature and the fire temperature of bitumen are different, and this applies to other petroleum products such as benzene, gasoline, kerosene, and oil.

In addition, to get familiar with bitumen Flash point detection test devices; We have attached some examples of them that you can see:

Bitumen Spot Test

One of the more important tests for bitumen would be the Spot Test we explained in our next article about it also.