The explanation of solid fuel is a solid combustible substance that can generate heat or power. Most of them are carbonaceous substances or hydrocarbons. Natural peat, coal, oil shale and firewood. Processing products include coke, semi-coke, charcoal and briquette. Its special varieties include solid alcohol, solid gasoline and solid rocket fuel. The word solid decomposition explains a state of matter, an object with a certain volume and shape and a relatively hard texture. Explain in detail the objects with certain volume, shape and hardness to distinguish them from liquids and gases. Such as metal, rock, wood, glass, rubber, etc. Are solid at room temperature. Fuel combustion materials used to generate heat or work, such as coal, coke, combustible gas, oil, peat and wood, are any materials that can release atomic energy, especially fissile materials used in nuclear reactors. Lu Xun's "Hot Wind Random Thoughts" Fifty-nine