煤炭中的微量元素是指与煤共生的锗、鎵、铀、釩和其它一些元素的总称。 已发现与煤共生元素有六十多种,其中:硅、沼、铁、钙、镁、硫等是主要元素,其它还有磷、砷、钻、铜、锌、锡等,有的还有金、银等贵重金属。 锗、鎵、铀、釩等四种元素,在煤中常常具有重要的工业价值。煤中锗一般品位为1～10PPM左右,当达到20PPM以上时,则可回收。锗大多富集于薄煤层中,以镜煤中较富集。锗是半导体和电子工业的重要原料。鎵是煤中的主要微量元素,一般工业要求含鎵量为30～50PPM,煤中常见为5～30PPM,而煤灰中可高达20～50PPM以上,鎵在电子、光电、原子能等方面有广泛的用途。铀在煤中的含量变化很大,由0～200PPM以上,一般工 Trace elements in coal refers to the symbiotic germanium, gallium, uranium, vanadium and other elements of the general term. More than 60 kinds of symbiotic elements have been found with coal, among which silicon, marsh, iron, calcium, magnesium and sulfur are the main elements, others are phosphorus, arsenic, diamond, copper, zinc and tin, Gold, silver and other precious metals. Germanium, gallium, uranium, vanadium and other four elements, often in the coal has important industrial value. Common grade of germanium in coal is about 1 ~ 10PPM, when it reaches more than 20PPM, it can be recycled. Most of the germanium is enriched in thin coal seams and enriched in the mirror coal. Germanium is an important raw material for the semiconductor and electronics industries. Gallium is the main trace element in coal, the general industry requires gallium content of 30 ~ 50PPM, 5 to 30PPM common in coal, and coal ash can be as high as 20 ~ 50PPM, gallium in electronics, optoelectronics, atomic energy and other aspects of a wide range the use of. The content of uranium in coal varies greatly, from 0 ~ 200PPM above, general work