![]() Germanic cognates include the Old Frisian kole, Middle Dutch cole, Dutch kool, Old High German chol, German Kohle and Old Norse kol, and the Irish word gual is also a cognate via the Indo-European root. The word originally took the form col in Old English, from Proto-Germanic * kula( n), which in turn is hypothesized to come from the Proto-Indo-European root * g( e) u-lo- "live coal". Indonesia and Australia export the most, followed by Russia. The largest consumer and importer of coal in 2020 was China, which accounts for almost half the world's annual coal production, followed by India with about a tenth. To meet the Paris Agreement target of keeping global warming below 2 ☌ (3.6 ☏) coal use needs to halve from 2020 to 2030, and "phasing down" coal was agreed upon in the Glasgow Climate Pact. Global coal demand is set to remain at record levels in 2023. Global coal use was 8.3 billion tonnes in 2022. The United Nations Secretary General asked governments to stop building new coal plants by 2020. As part of worldwide energy transition, many countries have reduced or eliminated their use of coal power. Fourteen billion tonnes of carbon dioxide were emitted by burning coal in 2020, which is 40% of the total fossil fuel emissions and over 25% of total global greenhouse gas emissions. The use of coal damages the environment, and it is the largest anthropogenic source of carbon dioxide contributing to climate change. ![]() The extraction and use of coal causes premature death and illness. Some iron and steel-making and other industrial processes burn coal. In 2020, coal supplied about a quarter of the world's primary energy and over a third of its electricity. With the invention of the steam engine, coal consumption increased. While coal has been known and used for thousands of years, its usage was limited until the Industrial Revolution. Vast deposits of coal originate in former wetlands called coal forests that covered much of the Earth's tropical land areas during the late Carboniferous ( Pennsylvanian) and Permian times. Ĭoal is a type of fossil fuel, formed when dead plant matter decays into peat and is converted into coal by the heat and pressure of deep burial over millions of years. Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. We are not responsible for any errors.Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. The grit sizes are defined by the number of lines per inch (25.4 mm) length of each sieve e.g. MM Micro-mesh grit in comparison to other standards. A Micron row is added to each FEPA P, FEPA F, JIS und ANSI row for comparison. As measuring unit it describes 1 thousandth of a millimeter (1 μ = 0.001 mm). MICRON (μ) is the letter "micron" in the Greek alphabet. JIS (Japanese Industrial Standard) issued by the Japanese Standards Association.ĪNSI American National Standards Institute. The decisive factor for comparison is FEPA F. The FEPA distinquishes between grain for sanding paper (FEPA P) and grain for sharpening stones or wheels (FEPA F) Definitions:įEPA (Fédération Européenne des Fabricants de Produits Abrasifs) Federation of European Producers of Abrasives. ![]() Use conventional abrasives as normal prior to going into the Micro-mesh stage. Use this Conversion chart to view the different standards and as a guide to know when you can start using Micro-mesh.
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