Propane is bought and stored in a liquid form (LPG), and thus fuel energy can be stored in a relatively small space. Compressed natural gas (CNG), largely methane, is another gas used as fuel, but it cannot be liquefied by compression at normal temperatures, as these are well above its critical temperature.
Anthracite accounts for about 1% of global coal reserves, and is mined in only a few countries around the world. China accounts for the majority of global production; other producers are Russia, Ukraine, North Korea, South Africa, Vietnam, the UK, Australia and the US.he term is applied to those varieties of coal which do not give off tarry or other hydrocarbon vapours when heated below their point of ignition. Anthracite ignites with difficulty and burns with a short, blue, and smokeless flame.
It is through the weathering of rocks, boric acid volatilization principally from the salt water, and the tough volcanic activity, the mine mineral boron is formed. In addition, it is also exhumed from anthropogenic resource to a certain extent. Anthropogenic sources consist of farming repudiate, and wood burnt as gas, power production using coal and oil, glass product produce, use of borates in the home and industry, etc.