bituminous

Bituminous is an adjective used to describe materials that contain bitumen or possess the properties of bitumen. Bitumen is a dense, viscous form of petroleum that is black or very dark in color. It occurs naturally in some geological deposits and is also produced during the refining of crude oil. Bituminous substances are typically sticky when warm, insoluble in water, and soluble in organic solvents; they have high waterproofing value and adhesive qualities.

In geology and mining, bituminous also denotes a rank of coal; bituminous coal is a relatively carbon-rich form with substantial volatile matter and is widely used as a fuel and as a feedstock in steelmaking (for coke production).

Applications of bitumen include asphalt for road surfaces, roofing and waterproofing materials, sealants, and protective coatings. In road construction, bitumen is heated and mixed with aggregate to form asphalt concrete, a durable paving material. Natural bitumen may occur in deposits such as oil sands (tar sands), where it is recovered by mining or in-situ methods and upgraded to synthetic crude oil.

Environmental and technical considerations include the energy requirements and emissions associated with extraction, upgrading, and use of bitumen-rich fuels, as well as the management of asphalt pavements at end of life.