What Is Coal Gas?
Coal gas, also known as coke oven gas, is a type of gas primarily produced in coke ovens, mainly at steel mills. Historically, it was the main raw material for city gas production. However, in recent decades, it has been primarily used as fuel in steel mills and for power generation.
Coal gas consists of approximately 50% hydrogen and 30% methane, along with smaller amounts of carbon monoxide, nitrogen, heavy hydrocarbons, and carbon dioxide. The emergence of the hydrogen energy era has sparked interest in producing hydrogen from coal gas.
Uses of Coal Gas
Coal gas is produced through the high-temperature dry distillation of coal in coke ovens. This process generates gases such as carbon dioxide, carbon monoxide, hydrogen, and methane, as well as steam, coal tar, benzol, and other byproducts, leaving behind coke.
The coke is utilized in steelmaking and foundry production, while coal tar finds applications as a plasticizer for vinyl chloride and polyester resin, in wood preservation, tire carbon black, rust prevention for cast-iron pipes, and in producing carbon materials, electrodes, and dyes.
Benzol is used to manufacture nylon, styrene, and paint solvents. Sulfur removed from the gas is converted into ammonium sulfate for use as chemical fertilizer. Additionally, hydrogen production from coal gas is an area of ongoing development.