Coal breaker Coal breaker A coal breaker is a coal processing plant which breaks coal into various useful sizes. Coal breakers also remove impurities from the coal (typically slate) and deposit them into a culm dump. The coal breaker is a forerunner of the modern coal preparation plant. Generally speaking, a coal tipple was typically used at a bituminous coal mine, where removing impurities was important but sorting by size was only a secondary, minor concern. Coal breakers were always used (with or without a tipple) at anthracite mines. While tipples were used around the world, coal breakers were used primarily in
Coal forest Coal forest Coal forests were the vast swathes of wetlands that covered much of the Earth's tropical land areas during the late Carboniferous (Pennsylvanian) and Permian times. As vegetable matter from these forests decayed, enormous deposits of peat accumulated, which later changed into coal. Much of the carbon in the peat deposits produced by coal forests came from photosynthetic splitting of existing carbon dioxide, which released the accompanying split-off oxygen into the atmosphere. This process may have greatly increased the oxygen level, possibly as high as about 35%, making the air more easily breathable by animals with inefficient respiratory systems,