Gas flaring is a combustion device to burn associated, unwanted or excess gases and liquids released during normal or unplanned over-pressuring operation in many industrial processes, such as oil-gas extraction, refineries, chemical plants, coal industry and landfills. Gas flaring is a significant source of greenhouse gases emissions. It also generates noise, heat and provided large areas uninhabitable. The World Bank reports that between 150 to 170 billion m3 of gases are flared or vented annually, an amount value about $ 30.6 billion, equivalent to one-quarter of the United States’ gas consumption or 30 % of the European Union’s gas consumption annually. Thus, a reduction or recover of gas flaring is a crucial issue. Therefore, there is a pressing need to measure flared gas by known its composition, distribution and volume, additionally, applied the suitable flare gas recovery system or disposal. This paper provides an overview of the gas flaring in industry and its composition, and its relevant environmental impacts. It also describes the flaring measurement techniques and the reduction of the flare gas by studying the different methods of flare gas recovery systems.
