Definition - What does Asphalt mean?
Asphalt (also called bitumen or tar) is a black, sticky and highly viscous liquid generated by petroleum refineries after crude oil distillation through a vacuum distillation unit. It is generally considered a byproduct or a residue of the refining process.
Asphalt is heavily used in road construction where it acts as glue or binder when mixed with road aggregate particles (sand, gravel and crushed stones) to create asphalt concrete. Other top uses include the production of bitumen waterproofing solutions (e.g., roof felt) and for sealing flat roofs (asphalt roll roofing).
Corrosionpedia explains Asphalt
Asphaltene (in the form of asphalt) is generated as a residual byproduct when crude oil is processed in a petroleum refinery. It is often used with bitumen to prepare tar, which is used for paving roads and waterproofing roofs.
Heavy crude oil is highly viscous and has high sulfur content. Refineries capitalize on the low-end petroleum byproducts such as asphalt, bitumen, lubricants and tar, which are sold to road product manufacturers and rubber tire manufacturers. The petroleum industry prioritizes the removal of asphaltenes from crude oil during processing because it is known to clog highly capitalized infrastructure, such as well tubulars, crude oil pipelines and subsurface equipment such as pumps and compressors. This clogging can eventually bring production to a halt and lead to corrosion in the refinery's infrastructure.
Heavy category crude oil has a high concentration of asphaltene but it usually remains stable during heavy crude oil production and thus it does not lead to well clogging. However, there is a greater chance of well clogging when producing a light category crude oil because it has varying amounts of asphaltene that may get deposited into the production tubes and clog them.