What is Bitumen (Asphalt) ?
Bitumen is a complex and complicated substance that has been recognized by human long years ago. Bitumen is a black to the dark brown sticky material, composed principally of high-molecular-weight hydrocarbons. Bitumen is a product of Crude oil Distillation. It is a semi-solid hydrocarbon product produced by removing the lighter fractions (such as liquid petroleum gas, petrol, and diesel) from heavy crude oil during the refining process. As such, it is correctly known as refined bitumen. “asphalt cement” or “asphalt” In North America, bitumen is commonly known as “asphalt cement” or “asphalt”. While elsewhere, “asphalt” is the term used for a mixture of small stones, sand, filler, and bitumen, which is used as a road paving material. At ambient temperatures, bitumen is a stable, semi-solid substance. Also, Bitumen naturally is beneath the earth crust as springs, lakes, and surface mines and occurs in the form of solid and liquid. In some countries, it can be found as a component of natural rock asphalt. History of Bitumen The Sumerians also used it as early as the third millennium BCE in statuary, mortaring brick walls, waterproofing baths, and drains, in stair treads, and for shipbuilding. Other cultures such as Babylon, India, Persia, Egypt, and ancient Greece and Rome continued these uses, and in several cases, the bitumen has continued to hold components securely together to this day. In some versions of the Book of Genesis in the Bible, the name of the substance used to bind the bricks of the Tower of Babel is translated as bitumen. Bitumen has been used for building construction and, even mummification. In fact, it was bitumen which had used by our ancestors and in the late nineteenth century had been used for making roads and pavements. Finally by discovering oil and create residual bitumen, the way to use a huge amount of bitumen been opened. Not all crude oils are sufficiently rich in heavy components to yield bitumen economically. Crude oils from Indonesia and Nigeria are examples of so-called light crudes containing very little suitable heavy residue. Heavy crude oils from the Middle East and South America usually have a large content of heavy residue suitable for bitumen. Statistics in 2007 shows that 110 million ton bitumen has been making annually in the world and Iran’s share is 4.3 million ton which by increasing the potential of refinery it will be increased. Today, Chemistry and chemical engineering in our country have developed so much in universities which we can see one or two or even trends of related fields can be seen in them. Bitumen is an unsung hero of our modern world. Asphalt cover with bitumen today make very smooth roads for light and heavy vehicles and high-quality runways for landing and takeoff aircraft and even good infrastructure for railways. Houses insulations and industrial functions like protecting coating of oil and gas pipes and power transportation lines holds out bitumen’s coating and being waterproof. A significant component of the asphalt we use to build roads, bitumen holds our city streets together and connects cities and countries across vast distances. It provides a backbone for personal and business travel, tourism and logistics. But it’s not just roads – bitumen is vital to all kinds of construction and infrastructure projects, large and small. Without bitumen our world would be a very different place; Our cities and our houses would be very different; our lives would be less mobile and less connected. This valuable material has countless uses and applications, and more are being discovered every year, thanks to research and development within the bitumen industry. Bitumen is not only flexible and multi-functional, it has a number of other benefits, too; It is fast to install and safe to use, as well as being durable and hard-wearing. It is easy to maintain and 100% recyclable, making it the perfect choice for forward-thinking construction and infrastructure projects. Bitumen is (solid, semi-solid, viscous), amorphous, cementitious material that can be found in different forms, such as rock asphalt, natural bitumen, tar and bitumen derived from oil, which is referred to as petroleum bitumen. Currently, most of the roads globally are paved with bitumen. Petroleum bitumen is typically referred to as bitumen or asphalt. In Europe for instance, bitumen means the liquid binder. In North America, on the other hand, the liquid binder is referred to as asphalt or asphalt cement. in general, the term “bituminous materials” is used to denote substances in which bitumen is present or from which it can be derived. Bituminous substances comprise of primarily bitumens and tars. Bitumen occurs in nature in several forms: hard one – easily crumbled bitumen in rock asphalt and softer, more viscous material which is present in tar sands and asphalt ‘lakes’. Another way in which bitumen can be obtained is through petroleum processing in this manner the bitumen is essentially the residue yielded through a distillation process of petroleum. Although bitumen can be found in natural form, the world currently relies for all purposes on petroleum. The material has been produced in this way for over a hundred years. Tars, on the other hand, do occur in nature. Tars drive as condensates from the processing of coal (at very high temperatures), petroleum, oil-shale, wood or other organic materials. The pitch is produced when a tar is partially distilled so that the volatile components have evaporated. Often coal tar is confused with bitumen however they are two entirely chemically different products and should not be mistaken. For the distinction drawn between petroleum bitumen and coal tar see the distinction table below:
|Origin||Naturally occurring||Derives from coal|
|Production||Petroleum processing from crude oil (petroleum), the process does not involve cracking or thermal conversation. Comes from animal matter.||Through a process of carbonization of coal pyrolysis of coal at a high temperature. It is essentially a by-product of the production of coke from coal. Comes from plants matter.|
|appearance||Black, sticky, viscose, thermoplastic||Thick, black, sticky liquid|
|applications||Currently, approximately 80% of bitumen demand is for road construction||Construction, medicine coal tar is also added to the dye treatments that are administered to the fabrics. |
Coal tar was also used for road construction and waterproofing until it was replaced by bitumen after the Second World War.