![]() ![]() ![]() The by-products of wood tar are turpentine and charcoal. Birch bark is used to make particularly fine tar, known as " Russian oil", suitable for leather protection. The heating ( dry distilling) of pine wood causes tar and pitch to drip away from the wood and leave behind charcoal. Traditional wooden boats are still sometimes tarred. Production nearly stopped in the early 20th century, when other chemicals replaced tar, and wooden ships were replaced by steel ships. Demand for tar declined with the advent of iron and steel ships. ![]() The largest user was the Royal Navy of the United Kingdom. Sweden exported 13,000 barrels of tar in 1615 and 227,000 barrels in the peak year of 1863. For centuries, dating back at least to the 14th century, tar was among Sweden's most important exports. Its main use was in preserving wooden sailing vessels against rot. Production and trade in pine-derived tar was a major contributor in the economies of Northern Europe and Colonial America. Producing tar from wood was known in ancient Greece and has probably been used in Scandinavia since the Iron Age. Wood tar is still used as an additive in the flavoring of candy, alcohol, and other foods. "Peasant Tar" might be named for the district of its production. In Scandinavia, it was produced as a cash crop. Tar kiln at Trollskogen in Öland, Sweden.įor at least 600 years, wood tar has been used as a water repellent coating for boats, ships, and roofs. Oil sands, almost exclusively produced in Alberta, Canada, are colloquially referred to as "tar sands" but are in fact composed of asphalt, also called bitumen. "Rangoon tar", also known as "Burmese oil" or "Burmese naphtha", is also a form of petroleum. Both "tar" and "pitch" are applied to viscous forms of asphalt, such as the asphalt found in naturally occurring tar pits (e.g., the La Brea Tar Pits in Los Angeles). There is a tendency to use "tar" for more liquid substances and "pitch" for more solid ( viscoelastic) substances. "Tar" and " pitch" can be used interchangeably asphalt (naturally occurring pitch) may also be called either "mineral tar" or "mineral pitch". Coal tar is produced from coal as a byproduct of coke production. Mineral products resembling tar can be produced from fossil hydrocarbons, such as petroleum. Tar can be produced from coal, wood, petroleum, or peat. Tar is a dark brown or black viscous liquid of hydrocarbons and free carbon, obtained from a wide variety of organic materials through destructive distillation. A tar-like substance can be produced from corn stalks by heating them in a microwave. ![]()
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